Ao Xiii, 1-2, 2006 Papers

Acta oecologica, vol. XIII, 1-2, 2006 1

CONTRIBUTIONS

AT THE AMPOI RIVER WATERSHED THERMIC SPECIFIC REGIME

Mihai Buiuc, Mircea Micu

Lucian Blaga University of Sibiu, Faculty of Sciences, Department of Ecology and Environment Protection, 31 Oituz St., Sibiu, RO - 550160

ABSTRACT This work prezent the altitudinal distribution of the thermic regime specific parameters with specific diferentiations for slopes and heights and also for valleys and depresions. Based on the thermic gradients study and of the microclimatics measurements made by the author was established the thermic inversions frequency and intensity and implicit the Ampoi Valley pollutants dispersal conditions. Key words: air thermic regime, thermic inversions, pollutants dispersal conditions. INTRODUCTION The Ampoi River, right side tributary of the Mure River has 59 km length, 576 km2 surface of the watershed and an average altitude of 700 m, altitudes which vary between 1060 m at the Ampoi River springs and 219 m at its confluence with the Mure River at Alba Iulia. The highest altitude (1300 m) in the Ampoi River basin, exist at the Vltori Valley springs. The Ampoi hydrographical basin is situated in the south-east part of the Apuseni Mountains, an area where the fhn efects were frequently registered. In all the Ampoi Watershed frequent thermal inversions were regisered, inversions which determine unfavourable polutants dispersal conditions, conditions highlighted by different researches (Buiuc 1974, 1979).


MATERIAL AND METHOD To characterize the Ampoi River watershed climate were considered the meteorological data of the Ampoi River watershed meteorological stations and posts (Tab. 1), and that ones from the neighboring areas. There were studied also Apuseni Mountains high altitudes meteorological stations data, which analyze allow the meteorological elements generalization in relation with the altitude, situation in which any interested area can be correctly characterize.

Tab. 1. The studied meteorological stations and posts. No. crt.

Meteorological station or post

Altitude m

Latitude N

Longitude E

1. Abrud 606 4617' 2304' 2. Aiud 290 4619' 2343' 3. Alba Iulia 248 4604' 2335' 4. Bioara 1384 4634' 2322' 5. Brban 249 4603' 2334' 6. Benic 300 4613' 2335' 7. Berghin 305 4604' 2344' 8. Bistra 546 4621' 2304' 9. Cmpeni 575 4622' 2303' 10. Ighiu 268 4609' 2331' 11. ntregalde 640 4614' 2325' 12. Mogo 750 4616' 2317' 13. Ponor-Geogel 742 4619' 2322' 14. Roia-Montan 850 4618' 2308' 15. Sebe 254 4557' 2334' 16. Teiu 239 4615' 2350' 17. Zlatna 423 4607' 2314'

Due to the fact that the 17 meteorological stations and posts data present not uniform values rows as duration, these were processed from the climatologically point of view to bring them at a common long period using for this purpose the longest values row - Sibiu, realizing the bringing data at a long common period (1851 - 2006).


The temperatures data processing was made based on the differences method, and for the precipitations, the ratios and the isopercentages method, in conformity with the methodology elaborated by Katin and Pekrovscaia (1964) and by Dumitrescu and Glja (1972). After the data were homogenised and bring at a common long period, the specific values were correlated with the altitude and was realized their altitudinal distribution in the Ampoi Watershed. The highest peak in the Ampoi Watershed is Vlcoi Peak (1348 m) situated at the Vltori Valley springs (Runc).

RESULTS AND DISCUSSIONS Ampoy Valley climate particularities The climate in this zone is characterised through some particularities which confirm and highlight its geographical individuality in comparison with other areas in Romania. These particularities are generated by the climatic factors, which has in the Ampoi Valley case a series of specific characteristics, determined by the geographical position and the specific phisico-geographical factors characteristics. The subjacent surface present in the Ampoi Valley a high diversity, conditioned by the specific particularities of the relief, hydrography, vegetation and soils, which induce a series of modifications in the regime and the territorial repartition of the radiative sum elements, and the general atmosphere circulation, which influence the appearance here of complex topoclimates in different parts of the basin. The human factors represented by the localities presence, roads and industrial pollution, influence in some degree the climate elements. The relief one of the main components of the subjacent surface has a special role in the solar energy transformation and of the moving air masses influence, therefore in forming the climate of this area. The average altitude of the Ampoi River watershed is 700 m, and has a lower influence then other local factors, yet the climatogenetic importance of the absolute altitudes of the relief is highlighted in this river watershed too through the differentiated repartition of the climatic elements on the different relief levels of this river basin.


In the Ampoi River basin the air temperature is inversely proportional distributed with the altitude, dropping with 0.5 - 0.6 C/100 m, yet in many months, in some moments of the day, some exceptions appear. In the majorities of the nights, due to the relief appear negative thermic gradients, due to the cold air moving from the neighbouring slopes and its accumulation on the bottom of the valley area and of the intense radiation of the subjacent surface. In these conditions temperature inversions are formed, inversions which increases the temperature contrasts from the lower and the higher parts of the basin, which in some cases remain above the temperature inversion layer. These exceptions from the normal thermic regime evolution are so important and frequent so that is reflected even in the multi annual average temperature, which is lower around the river. The vertical zonality affected the precipitations quantities distribution too. The relief exposition and inclination has also important roles in the climatic elements distribution, especially for the thermic regime. The Ampoi Valley relief form, contribute to the dynamisation of the atmosphere and to the thermic inversions long persistence, which accentuate the polluted air stratification over the localities around the pollution sources, with the night periods when mountain breezes move the polluted air masses downstream to Alba Iulia. Also the accentuated air masses stratification induced the air nebulosity presence on the Ampoi River valley and the increasing of water vapours presence, reducing the visibility and diminishing the receipted solar radiation. The main climatic elements characterization in the Ampoi River watershed 1. Air temperature 1.1. Average annual and monthly temperatures The air temperatures are one of the main factors which allow the human activities. The Ampoi River watershed main specific relief forms with the general atmospheric circulation and the solar radiation has a very important influence on the territorial distribution and evolution in time of the air temperature.


Trough the existing data analysis, correlated with the altitude, result the fact that in Ampoi Watershed the average annual temperatures decrease from the confluence of the Ampoi River with the Mure River (Alba Iulia 9.4 C) to the mountains peaks river springs area, the lowest annual values of 4.7 C existing on the Vlcoi Peak (1348 m) at the Vltori Valley springs (Runc) (Tab. 2).

Tab. 2. The average monthly and annual temperatures (C) at different altitudinal levels on the Apoi Valley (1851 - 2005).

months Alti tude m I II III IV V VI VII VIII IX X XI XII A

n

n

u

a

l

200 -3.9 -1.2 4.5 10.4 15.6 18.8 20.5 19.8 15.7 9.9 4.2 -1.1 9.4 250 -3.9 -1.0 5.0 10.5 15.7 19.0 20.3 19.7 15.9 9.9 4.5 -0.9 9.6 300 -3.7 -0.9 4.8 10.3 15.5 18.3 20.2 19.5 15.6 9.7 4.2 -0.8 9.4 350 -3.6 -1.0 4.6 10.1 15.2 18.0 20.0 19.3 15.3 9.6 4.0 -0.8 9.2 400 -3.7 -1.2 4.2 9.8 14.8 17.7 19.7 19.0 15.0 9.4 3.7 -0.9 9.0 450 -4.0 -1.5 3.8 9.6 14.6 17.5 19.4 18.5 14.5 9.2 3.4 -1.2 8.6 500 -4.3 -1.9 3.3 8.7 14.2 16.9 18.7 17.9 14.0 8.8 3.1 -1.6 8.2 550 -4.0 -2.0 3.1 8.3 14.0 16.5 18.3 17.7 13.7 8.5 2.8 -1.5 8.0 600 -3.7 -2.1 2.9 7.9 13.7 16.1 17.8 17.4 13.3 8.1 2.4 -1.3 7.7 650 -3.7 -2.2 2.7 7.6 13.5 15.8 17.5 17.1 13.0 7.9 2.2 -1.4 7.5 700 -3.7 -2.4 2.4 7.2 13.2 15.4 17.1 16.7 12.7 7.6 1.9 -1.6 7.2 750 -3.7 -2.5 2.2 6.9 12.9 15.1 16.8 16.5 12.4 7.5 1.8 -1.7 7.0 800 -3.7 -2.7 1.9 6.5 12.6 14.7 16.4 16.2 12.1 7.4 1.7 -1.9 6.8 850 -3.8 -2.8 1.7 6.2 12.3 14.4 16.1 15.9 11.9 7.2 1.6 -2.0 6.6 900 -3.9 -3.0 1.4 5.8 11.9 14.1 15.8 15.5 11.6 6.9 1.5 -2.1 6.3 950 -3.9 -3.1 1.1 5.5 11.6 13.8 15.5 15.3 11.4 6.8 1.4 -2.2 6.1 1000 -4.0 -3.3 0.8 5.1 11.2 13.5 15.2 15.0 11.2 6.6 1.3 -2.3 5.8 1050 -4.1 -3.5 0.5 4.8 10.9 13.2 15.0 14.8 11.0 6.5 1.2 -2.4 5.6 1100 -4.2 -3.7 0.2 4.5 10.5 12.8 14.7 14.5 10.8 6.3 1.1 -2.5 5.4 1150 -4.3 -3.8 0.1 4.2 10.1 12.5 14.4 14.3 10.6 6.2 1.0 -2.6 5.2 1200 -4.5 -3.8 -0.1 4.1 9.7 12.2 14.1 14.1 10.5 6.2 1.0 -2.6 5.1 1250 -4.6 -3.9 -0.5 9.0 9.3 12.0 13.9 13.9 10.4 6.1 1.1 -2.7 4.9 1300 -4.7 -4.0 -1.0 3.8 8.9 11.7 13.6 13.6 10.3 6.0 1.1 2.7 4.7

If the normal thermic gradient is 0.65 C/100 m, in the Ampoi Valley conditions can be observed a lower thermic gradient 0.43 C/100 m, at this situation contributing also the frequent thermic inversions. Along the studied period of time the highest average annual temperature was 11.2 C and it was registered at Ighiu (268 m) in 1958, and in the mountainous area 8.0 C in 1966 at Bioara (in the vicinity of the interested area). The lowest average annual temperatures were 7.8 C in 1940 at Alba Iulia (248 m) and 6.2 C in 1964 in the mountainous area at Bioara (546 m).


In dependence with the baric centres succession, with the radiative sum elements, with the subjacent surface characteristics in different periods of the year, the year average temperature present variations along the year from one month to another (Tab. 2). The winter last around three months in the lower part of the Ampoi River watershed, and at over 1000 m altitude it include also the first half of March, and over 1200 m altitudes the winter last four months (December - March). In this cold season an intensive radiative cooling take place, favoured by the persistence of the anticyclone regime, the long nights period and the presence of the snow layer. Due to these characteristics the cold air is accumulating on the Ampoi River valley, the average winter months temperatures being lower on the valley bottom than on the neighbouring mountain peaks, especially in January, when the lowest temperatures were registered between 3.7 C and - 4.7 C. In the basin sector between 500 m and 1000 m altitude exist a zone with thermic inversion, a zone which can be observed even from the average monthly temperatures (Tab. 2). In the spring due the solar radiation increasing, and the frequent warm air masses from west and south-west, the air temperature became positive, the average of the season vary between 8.7 and 10.2 C in the lower part of the basin (200 - 500 m) and decrease in the mountainous area between 5.7 and 3.9 C (at altitudes of 1000 - 1300 m). In the spring the average temperatures increase with 7.7 - 12.3 C in comparison with the winter average temperatures. In the first part of the season, the air temperatures remain low on the Ampoi Valley bottom due to the thermic inversions. The highest monthly increasements along the year are registered in March and April when are over 5 - 6 C (Tab. 2). Starting with April, the valley bottom became warm and the temperatures evolution in relation with the altitude became normal - on the whole altitudinal gradients profile being almost similar with those considered standard (0.65 C). In the spring as a consequence of the solar radiation increasing, of the thermic convection development, the air temperature register the highest values, varying in average in this season between 19.4 C at


Ighiu and 19.6 C at Alba Iulia. In the mountainous zone the average summer temperature decrease at 18.6 C at Zlatna (423 m) and at 16.1 C at Mogo (750 m). At the level of the mountainous peaks starting with the 1200 m altitude, can be observe a one month delay in the appearance of the maximum monthly values. If till the 1200 m altitude the highest monthly average temperature were recorded in July, at highest altitudes the highest values were recorded in August (Tab. 2). In the autumn, due to the solar energy intensity flux decreasing and the increasing of the number of the days with "cover" sky (5 - 15 days monthly), the air temperature start to decrease, being with 9 - 10 C lower then in summer, varying in the lower part of the Ampoi Watershed between 9.6 C at Ighiu and 9.8 C at Alba Iulia, decreasing at 9.2 C at Zlatna, and at altitudes higher than 1000 m decrease under 6.3 C. In the autumn the air temperature is with approximative 1 C higher than in spring, due to the missing of the snow layers and the presence of the fehnal efects. The annual air temperatures amplitudes present values which vary between 18.3 C and 24.4 C, these amplitudes being lower in the mountainous zone and higher in the Mure River valley. The highest monthly air average temperature of the studied period was registered at Alba Iulia in July 1930 (23.5 C) and in July 1987 at Ighiu (23.4 C), and the lowest monthly average air temperature of the studied period was registered in January 1940 at Alba Iulia (- 10.9 C). In the year round dynamic the monthly average temperatures present a minimum in January and a maximum in July. One exception was registered at altitudes over 1200 m, where the annual maximum was registered both in July and in August - the passing at the distribution type characteristic for the high mountainous areas. 1.2 The average annual and monthly temperatures 1.2.1 The average daily maximum and minimum temperatures The multiannual monthly averages of the daily maximum temperatures (Tab. 3) are positive all over the year in the lower areas, with the exception of January when the maximum averages temperatures decrease at some stations a little under 0 C (Ighiu, - 0.3 C).


Tab. 3. The daily maximum average air temperatures (C). months Alti

tude m I II III IV V VI VII VIII IX X XI XII A

n

n

u

a

l

200 0.3 3.9 10.5 16.8 21.7 25.4 28.1 26.6 22.7 15.9 9.3 3.0 15.4 300 0.3 3.6 9.8 16.2 21.0 24.5 26.9 26.1 22.2 15.8 9.0 2.9 14.8 400 0.3 3.2 9.0 15.5 20.4 23.5 25.7 25.5 21.7 15.7 8.6 2.7 14.3 500 0.6 3.0 8.7 15.1 20.1 23.2 25.3 25.2 21.4 15.2 8.4 2.7 14.1 600 0.7 2.7 8.3 14.6 19.6 22.8 24.9 24.6 20.9 14.7 8.2 2.6 13.7 700 0.8 2.3 7.6 14.0 19.0 22.3 24.3 24.1 20.3 14.2 7.9 2.4 13.3 800 0.7 1.9 7.1 13.3 18.4 21.6 23.6 23.4 19.7 13.6 7.5 2.2 12.8 900 0.5 1.5 6.4 12.5 17.6 20.9 22.8 22.6 19.0 12.9 7.0 2.0 12.1 1000 0.3 1.0 5.7 11.6 16.7 20.0 22.0 21.8 18.2 12.3 6.5 1.8 11.5 1100 -0.1 0.5 4.9 10.7 15.8 19.1 21.1 21.0 17.3 11.6 6.0 1.5 10.8 1200 -0.5 0.0 4.1 9.8 14.8 18.1 20.2 20.1 16.5 11.0 5.4 1.2 10.0 1300 -1.0 -0.5 3.2 8.8 13.8 17.0 19.2 19.3 15.5 10.3 4.9 0.9 9.3

Through the average maximum temperatures correlation with the altitude (Tab. 3) can be highlight the fact that only at altitudes over 1100 m these values are negative in January, and at altitudes over 1300 m became negative for two months every year (January and February). The multiannual monthly averages of the daily minimum temperatures were differentiated on altitudinal levels for slopes and heights and for valleys and depressions. In the table 4 are presented the multiannual monthly average values for slopes and heights and in the table 5 the same category of values for valleys and depressions.

Tab. 4. The daily minimum average air temperatures (C) in the Ampoi River watershed; slopes and heights.


n

n

u

a

l

200 -6.3 -2.9 1.3 5.8 10.4 14.3 15.4 14.6 10.3 5.6 2.4 -2.7 5.7 300 -6.9 -3.4 0.4 4.9 9.5 12.7 14.8 14.2 9.9 5.3 2.0 -2.5 5.1 400 -7.2 -4.1 -0.3 4.1 8.8 11.7 13.8 13.3 9.5 4.7 1.2 -2.3 4.4 500 -7.4 -4.6 -0.9 3.9 8.1 11.0 12.5 12.2 9.0 3.9 0.3 -2.2 3.8 600 -7.5 -5.1 -1.5 2.9 7.5 10.5 11.5 11.3 8.4 3.4 -0.2 -2.3 3.2 700 -7.6 -5.4 -2.0 2.3 7.0 10.0 11.2 11.0 8.1 3.2 -0.3 -2.9 2.9 800 -7.6 -5.8 -2.4 1.9 6.6 9.6 11.0 10.8 7.9 3.1 -0.4 -3.3 2.6 900 -7.5 -6.0 -2.7 1.5 6.2 9.3 10.8 10.6 7.7 3.0 -0.5 -3.7 2.4 1000 -7.5 -6.3 -3.0 1.1 5.8 9.1 10.7 10.5 7.5 3.0 -0.5 -4.0 2.2 1100 -7.4 -6.5 -3.2 0.9 5.7 9.0 10.6 10.5 7.5 3.1 -0.6 -4.3 2.1 1200 -7.2 -6.3 -3.1 0.8 5.6 8.9 10.6 10.5 7.5 3.2 -0.6 -4.5 2.1 1300 -6.8 -6.1 -3.0 0.8 5.6 8.9 10.6 10.5 7.5 3.5 -0.7 -4.5 2.2


Tab. 5. The daily minimum average air temperatures (C) in the Ampoi River watershed; valleys and depressions.


n

n

u

a

l

200 -8.1 -4.7 -1.3 4.0 8.6 12.5 13.6 12.8 8.5 3.8 0.6 -4.5 4.5 300 -8.7 -5.4 -1.4 3.1 7.7 10.9 13.0 12.4 8.1 3.5 0.2 -4.3 3.2 400 -9.0 -5.9 -2.1 2.3 7.0 9.9 12.0 11.5 7.7 2.9 -0.6 -4.1 2.6 500 -9.2 -6.4 -2.7 1.6 6.3 9.2 10.7 10.4 7.2 2.1 -1.5 -4.0 2.0 600 -9.3 -6.9 -3.3 1.1 5.7 8.7 9.7 9.5 6.6 1.6 -2.0 -4.1 1.4 700 -9.4 -7.2 -3.8 0.5 5.2 8.2 9.4 9.2 6.3 1.4 -2.1 -4.7 1.1 800 -9.4 -7.6 -4.2 0.1 4.8 7.8 9.2 9.0 6.1 1.3 -2.2 -5.1 0.8 900 -9.3 -7.8 -4.5 -0.3 4.4 7.5 9.0 8.8 5.9 1.2 -2.3 -5.5 0.6 1000 -9.3 -8.1 -4.8 -0.7 4.0 7.3 8.9 8.7 5.7 1.2 -2.3 -5.8 0.5 1100 -9.2 -8.1 -5.0 -0.9 3.9 7.2 8.8 8.7 5.7 1.3 -2.4 -6.1 0.3 1200 -9.0 -8.1 -5.1 -1.0 3.8 7.1 8.8 8.7 5.7 1.4 -2.4 -6.3 0.3 1300 -8.8 -7.9 -4.8 -0.8 4.1 7.1 8.8 8.7 5.7 1.7 -2.5 -6.3 0.4

After this values examinations, can be reveal the fact that the daily minimum averages air temperatures on slopes and heights had negative values three months a year in the lower part of the basin till 300 m altitudes, and on higher altitudes the time period with the average minimal negative temperatures increase to 4 months by year (till 600 m) and 5 months by year over 600 m altitudes (Tab. 4), where the frozen periods start in November and last till March. In absolute values, the lowest daily minimum averages air temperature (- 7.6 C) on slopes and heights were registered in January between 700 - 800 m altitudes, and the highest (15.4 C) were registered in July in the confluence with the Mure River area and decrease gradually with the altitude till 10.6 C at 1300 m. The vertical thermic gradients are small and appear isothermic cases, facts which create unfavourable conditions for the pollutants dispersion. On the valleys and depressions (mainly the confluence areas of the Ampoi with its tributaries), the daily minimum temperature average prezent negative values five months a year (November - March) till 900 m altitude, and at higher altitudes these values are negative six months a year (November - April). In comparison with the daily minimum temperatures averages on the slopes and heights, those from the valleys and depresions are with 1.5 - 2.0 C higher. On the Ampoi Valley the freezing periods last with 30 days more then on slopes and hights.


In absolute values, the lowest daily minimum temperatures averages in valleys and depresions are registered in January at altitudes between 500 and 1100 m and vary between - 9.2 C and - 9.4 C, and the highest (13.0 - 13.6 C) in July in the lower area of the confluence with the Mure River. If in the summer time these values decrease with the altitude with lower gradients in the comparison with the standard gradients, in winter months the gradients are very low (0.1 C/100 m) or izotermic layers can be registered (at 700 - 1000 m). From the table 5 data result the fact that the daily minimum temperatures averages vary along the year bewten the lowest values (- 8.1 C and - 9.4 C) in January and highest values between (8.8 C and 13.6 C ) in July. 1.2.2 The absolute maximum and minimum temperatures The absolute maximum temperatures in the Ampoi River watershed was 39.4 C, a registered value in 09.07.1947 at Alba Iulia, folowed by the 39.2 C value registered at Ighiu in 25.07.1987, and in the mountainous area of the Apuseni Mountains was recorded at Cmpeni (591 m) the 38.7 C value in 19.07.1987. The monthly absolute maximum values analise highlight the fact that starting with March till November these values are usualy higher then 20 C, and in May (and even in April) till in Octomber, the absolute maximum temperatures are frequently over 30 . In June - August period the absolute maximum temperatures are over 35 C. The absolute minimum temperatures became negative starting with September and remain negative till in May. The absolute minimum temperatures (- 32.4 C) were registered in 24.01.1963, at the confluence with the Ampoi River with the Mure River, also - 32,4 C at Ighiu and - 32.7 C at Cmpeni. As the absolute extremes are punctual values in table 6 where are presented the absolute maximum temperatures, and in the table 7 the registered minimal absolute values. In the table 7 can be observe that the absolute minimum values decrease for one - two months under - 30 C. In the cold season, two months (Ighiu), four months (Alba Iulia, Sebe Alba, Cmpeni, Bioara) the absolute minimum values decrease under - 20 C.


Tab. 6. The absolute maximum temperatures (C) of the air and the registration data, in the Ampoi Watershed; m - absolute maximum temperatures (C), d - day of registration, y - year of registration, A - Alba Iulia, S - Sebe-Alba, I - Ighiu, C - Cmpeni, B - Bioara.

months

S

t

a

t

i

o

n

I II III IV V VI VII VIII IX X XI XII Annual

m 15.4 17.5 28.6 31.4 33.2 35.2 39.7 39.4 38.5 32.1 20.4 17.5 39.7 d 17 26 30 21 26 19 9 19 7 2 4 3 9.07 A y 1948 1948 1948 1950 1950 1952 1947 1946 1946 1952 1960 1947 1947 m 15.0 20.6 27.8 29.8 34.3 36.4 38.6 37.7 34.6 29.7 23.6 18.3 38.6 d 7 22 31 17 12 16 26 12 14 13 7 17 26.07 S y 1988 1966 1968 1956 1958 1972 1965 1961 1987 1964 1963 1989 1965 m 15.2 20.7 27.6 31.5 34.0 35.4 39.2 38.4 35.4 32.0 24.5 18.6 39.2 d 2 22 30 24 6 27 25 16 14 2 1 11 25 I y 1984 1966 1952 1950 1968 1982 1987 1952 1987 1952 1970 1979 1987 m 12.6 19.0 24.6 27.3 30.3 32.5 38.7 33.7 32.1 27.0 21.1 16.0 38.7 d 7 24 21 24 16 28 19 18 7 2 6 16 19.07 C y 1988 1990 1974 1968 1969 1963 1987 1963 1982 1963 1963 1989 1987 m 12.8 15.4 17.2 20.6 24.2 26.5 29.6 26.6 25.3 21.1 19.5 14.6 29.6 d 16 25 21 25 16 27 6 12 7 2 6 5 6.07 B y 1975 1978 1974 1968 1969 1982 1988 1961 1982 1965 1987 1985 1988

Tab. 7. The absolute minimum temperatures (C) of the air and the registration data, in the Ampoi Watershed; m - absolute maximum temperatures (C), d - day of registration, y - year of registration, A - Alba Iulia, S - Sebe-Alba, I - Ighiu, C - Cmpeni, B - Bioara.

months

S

t

a

t

i

o

n

I II III IV V VI VII VIII IX X XI XII Annual

m -31.0 -30.0 -21.0 -5.7 -1.6 2.5 6.2 5.1 -1.2 -6.7 -14.7 -24.0 -31.0 d 31 1 2 13 21 1 23 26 26 27 30 29 31 A y 1947 1947 1932 1954 1952 1960 1951 1952 1952 1966 1948 1939 1947 m -33.9 -27.6 -21.4 -5.1 -0.6 1.2 5.2 3.4 -4.2 -8.5 -14.9 -23.5 -33.9 d 24 6 4 3 4; 5 3 10 27 30 29 26 13 24.01 S y 1963 1954 1987 1974 1965 1990 1962 1980 1970 1971 1976 1983 1963 m -32.4 -27.6 -19.6 -5.4 -1.5 4.0 6.0 4.1 -3.0 -6.6 -15.5 -19.6 -32.4 d 24 6 5 13 21 5 23 13 30 29 30 24 24.01 I y 1963 1954 1987 1954 1952 1965 1951 1965 1970 1971 1948 1948 1963 m -32.7 -30.8 -23.0 -6.0 -3.4 0.6 2.3 1.5 -5.5 -9.3 -18.6 -24.1 -32.7 d 24 15 1 21 1 2 16 26 28 28 30 4 24.01 C y 1963 1964 1965 1984 1976 1977 1969 1980 1968 1988 1987 1973 1963 m -25.3 -22.4 -22.5 -11.0 -5.5 -3.8 1 0.2 -6.7 -10.9 -15.6 -20.4 -25.3 d 17 6 1 2 2 7 1 28 29 25 29 15 17.01 B y 1964 1965 1963 1965 1962 1962 1962 1981 1970 1979 1989 1961 1964


The absolute minimum temperatures remain negative nine months per year, the latest freezing period was registered in 21 May 1952, and the first freezing periods in autumn were registered between 26 and 30 September (1952, 1968 and 1970). 1.2.3 The freezing days frequency The first autumn day with freezing temperatures is register usualy in the second decade of Octomber, and the last spring day with freezing temperatures is register usualy in the second decade of the April. If we analise the registered data at the Ampoi River and Mure River confluence (Alba Iulia) for the first autumn day with freezing temperatures in pluriannual average this one is 17.10, and the last such day is 12.04. The average period of the annual number of days without freezing temperatures is 188 at Alba Iulia, respectively 177 days with probable freezing temperatures. The first autumn freezing at Alba Iulia was in 24.09 and the latest in 14.11. The last spring freezing day at Alba Iulia can appear in the warm springs till 14.03, and in that springs with climatic accidents in 22.05. 1.2.4 The winter days frequency (with maximum temperatures lower or equal with 0 C) and of the nights with frosty weather (the minimum temperatures equal or lower than - 10 C) The winter days number (the maximum air temperatures lower or equal with 0 C), is lower than the frosty weather days number, varying between 28.2 days at Ighiu, 29.4 days at Alba Iulia and 47 days/year at 1300 m. Winter days distribution studing at diferent altitudinal levels, reveal the fact that these days frequency increase with the altitude with 1.7 days/100 m, being over 30 days/year on altitudes higher than 500 m and over 40 days/year at higher than 1000 m altitudes. The maximum winter days on an year vary between 35 and 60, and the minimum winter days vary between 16 and 25 days. The frosty weather nights number (the minimum temperatures equal or lower than - 10 C) vary between 21.3 days in the Ampoi and Mure rivers confluence area, increasing at 35.0 days in the higher watershed area. It has to be added the fact that in the Inghiu vineyards area the frequency of the frosty nights is lower (15.8 days/year).


1.2.5 The summer days number on an year (with maximum temperatures higher or equal with 25 C) and of the tropical days on an year (with maximum temperatures higher or equal with 30 C) In the warm season, the annual number of the summer days (with maximum temperatures higher or equal with 25 C) varies between 76.6 days at Alba Iulia and 80.5 days at Ighiu. The distribution of these categories of days in relation with the altitude show that over 100 m the frequency of these days decrease with 6.8 days, thus at the altitudinal level of 500 m were registered 39.5 summer days, at 800 m 15 summer days, and at 1300 m only 1.5 days. In the analysed period for the lower watershed were registered the years when the number of summer days was over 100 days and in cold years the frequency of these days decrease at 40 - 50 days. The early days with maximum temperatures higher or equal with 25 C appear (one - two days) in March. In April the summer days number were registered usually in two days. Due to the solar radiation intensification starting with the month of June, the summer days number in the lower area of the Ampoi Watershed increase at 15 - 20 days\month and sometimes more. The air warming over 25 C has the highest frequency in July and August when in the area were registered 22 summer days (6 - 8 less such days then in the southern Romanian Plain). In Octomber were registered the last days with maximum temperatures higher or equal with 25 C, 1 - 1.5 days in the lower area and no such days in the mountanous area. The tropical days number (with maximum temperatures higher or equal with 35 C), vary in the lower area of the Ampoi River watershed between 19.5 days at Ighiu and 21.8 days at Alba Iulia, decreasing at 10.8 days at 550 - 600 m altitudes, and at higher altitudes these days number strongly decreased till their disapearance at the mountainous peaks level (1200 - 1300 m). 1.2.6 Air daily average temperatures passing through 0 C level To study the passing of the air daily average temperatures by 0 C level the histograms method was used. Were determined the beginning, the end and the average period in days of the interval with


daily average temperatures equals or higher than 0 C, values which determine the heat necesity and the posibility of outdoors human activities. In the table 8 are present these data for the altitudinal levels between 200 m in the Ampoi and Mure rivers confluence area, till the highest area of the basin (1300 m).

Tab. 8. The beginning, the end and the period in days of the interval with daily average temperatures equals or higher than 0 C and the global thermic resources at different altitudinal levels in the Ampoi Watershed.

Altitude m Begining End Interval

Global thermic

resources 200 18.02 11.12 296 3680 300 19.02 10.12 294 3645 400 22.02 7.12 288 3490 500 28.02 3.12 278 3215 600 5.03 29.11 269 2835 700 8.03 27.11 264 2658 800 12.03 25.11 258 2535 900 15.03 23.11 253 2435 1000 19.03 22.11 248 2350 1100 21.03 21.11 245 2275 1200 23.03 20.11 242 2205 1300 25.03 20.11 240 2135

From the presented data in the table 8 it can be observed the fact that the begining of the period with temperatures higher than 0 C was registered in 18.02 and is later with 35 days to 25.03 at the altitudine of 1300 m. The end of the period with higher or equal with 0 C values was produced in 11.12 in the Ampoi and Mure rivers confluence area, and in 20.11 at 1300 m altitudes, thus at the Ampoi River springs it is happened 21 days earlier than in the confluence area. The duration of the period with daily average temperatures higher the 0 C decrease from 296 days in the Ampoi and Mure rivers confluence areas to 240 days in the Ampoi River springs area (1500 m), thus with 56 days earlier in the springs area than in the confluence area.


It results that the period with positive temperatures decrease in average with 5.1 days for each 100 m. On the bottom of the valleys this value differ with one to two days in comparison with the slopes and the highest points, due to the thermal inversions. The global thermic resources, respectively the summ of the daily positive average temperatures vary between 3680 C in the area of the Ampoi and Mure rivers confluences, droping to 2135 C at the 1300 m altitude at the Ampoi River springs area, resulting a decreasing of the global thermal resources with 140.4 C/100 m atitude. 1.2.7 The specific thermic inversions for Ampoi Watershed The thermic inversions estimation was made through a careful analyse of the temperature and relative humidity registrations from the meteorological stations which border the area, and through special microclimatic measurements realised in characteristic moments of the day and of the year. This analise and the measurements analises pointed out the frequent temperature inversions existence in 41.4 - 54.1 % of the time (Buiuc, 1979). The thermic inversion frequency is high in cloudless days and low in cloudy days. The maximum period of the thermic inversions were registered in the cloudless days. The termic inversions appear sudenly in afternoons (16 - 17) in a 200 - 300 m thick air layer from the valey bottom, and around the midnight are over the mountainous tops (a 500 m thick air layer). The thermic inversions break up start from the soil surface around 10 - 11 in winter and 8 - 9 in summer, and the end of the termic inversion is hapened around the noon. The dominant winds directions on the Ampoi Valley are the west and the east, at this situation contributing the general atmosphere circulation and the local circulation - valley breeze and mountain breeze. On the valleys the atmospheric calm has a high frequency (40 - 50 % of the cases), fact which induce the stable stratification of the atmosphere and as a consequence the pollutants unfavourable dispersal conditions. At the level of the Metaliferi Mountainous tops increase the wind frequence and speed, registered daily with 4 - 5 m/second.


CONCLUSIONS The monthly average temperatures present a maximum of (136 C to 205 C) in July and a minimum (- 3.9 C to - 4.7 C) in January. The anual average temperatures decrease from 9.6 C in the lower area (vine yards area) to 4.7 C in the mountainous area of the watershed. The maximum daily averages temperatures has the highest values in July (19.2 C to 28.1 C) and the lowest values in January (- 1.0 C to 0.2 C. The minimum daily averages temperatures has the highest values in July (10.6 C to 15.4 C) and the lowest values in January (- 6.3 C to - 7.6 C) on slopes and hights. The altitudinal dynamic of these values clearly indicate the existence of some thermic inversions, inversions present over the neighbouring mountaionous tops level too in winter, and in the warm season the temperatures decrease in altitude with very low termic gradients, which induce a stabile stratification of the atmosphere in the warm season too, also frequent being the isotermiies. In the valleys and depresions the average minimum temperatures values are lower with 2 - 3 C in comparison with the slopes and hights. The absolute maximum temperatures are over 30 C in the whole Ampoi River watershed 7 months a year (IV - X) and are positive all the year long. The absolute minimum temperatures decrease under - 30 C in January and February and can have negative values 9 months a year. The temperature inversions are very frequent (41.4 - 54.1 % of the time), and are very accentuated in the cloudless days. Due to the temperatures inversions and of the isotermmies exist very unfavourable dispersal conditions for the pollutants, and the valley and mountain breesees induce the polluted air masses movement upstream and downstream.


REFERENCES 1. Buiuc M., 1974, - Particulariti microclimatice ale distribuiei

elementelor meteorologice pe vile rurilor din Munii Apuseni. 2. Buiuc M., 1979, - Particulariti microclimatice ale vii Arieului

n zona Cmpeni - Valea Lupei, Studii i cercetri partea I - a Meteorologie, Institutul de Meteorologie i Hidrologie, Bucureti.

3. Dumitrescu E., Glja M., 1972, - Metodica prelucrrii datelor climatologie, Ed. Universitii, Bucureti.

4.

Katin S, Pekrovskaia T.V., 1964 - Climatologie, metode de prelucrare a datelor climatologice, Editura tiinific, Bcureti.


HIDROLOGICAL CONSIDERATIONS REGARDING

THE AMPOI HYDROGRAPHIC BASIN

Vasile tef*, Rodica Ciobanu**, Valer Dobros***

* Tourism Geography Faculty of Sibiu, 5-7, S. Mehedini St., Sibiu, RO - 550182 ** Natural History Museum, 1 Cetii St., Sibiu, RO - 550160, [email protected] *** Lucian Blaga University of Sibiu, Faculty of Sciences, Department of Ecology and Environment Protection, 31 Oituz St., Sibiu, RO - 550160

REZUMAT

Reeaua hidrografic a rului Ampoi este reprezentat de rul Ampoi i dintre afluenii mai importani Vltori, Fene, Ampoia, Ighiu. Pentru analiza proceselor i fenomenelor hidrografice din bazinul Ampoi s-au prelucrat observaiile i msurtorile efectuate la staiile hidrometrice (prezentate n detaliu n lucrare), care demonstreaz c ntre parametrii hidraulici i morfometrici ai albiilor exist legturi corelative. Bazinul hidrografic al Ampoiului desfurat pe uniti fizico-geografice diferite, alctuite dintr-o multitudine de roci genereaz o mare varietate a scurgerii solide.

Creterea debitelor are ca efect reducerea rugozitii, amplificarea pantelor i vitezelor de deplasare prin albie. Dup viitur debitul de ap revine la situaia de dinainte. Revenirea la situaia preexistent reflect un anumit echilibru ntre alimentarea cu aluviuni, depunerea la scdere i cedarea aluviunilor din albie ctre scurgere, de aluviuni din aval. Este cazul staiilor hidrometrice Izvorul Ampoiului. Rul Ampoi i desfoar cursul peste roci dure cu friabilitate redus de tipul calcarelor, rocilor vulcanice, metamorfice. n aceste seciuni variaia este nesemnificativ, compoziia geologic constituie factorul dominant n realizarea stabilitii albiei. Fenomenul de adncire a albiei este specific tuturor staiilor hidrometrice amplasate n cursurile inferioare, depresiunile intramontane (Depresiunea Zlatna).


Scurgerea apei (medie, maxim i minim) este sub directa influen a climei, a factorilor fizico-geografici al M. Trascu i Metaliferi. Se evideniaz o bogat scurgere din zonele nalte care se reduce o dat cu dezvoltarea suprafeei bazinale n cazul scurgerii medii. Debitele maxime realizate, n special n urma unor precipitaii maxime, sunt cele mai mari valori, realizndu-se n sezonul de var. Debitele minime sunt influenate de o bogat scurgere carstic, i au ca efect meninerea unor debite minime pe tot parcursul rului chiar dac n cursurile inferioare predomin infiltraia n propriile aluviuni. Key words: Apuseni Mountains, Ampoi Basin, hydrology. INTRODUCTION

The Ampoi Basin was in the attention of the geologists, in the last decades of the last century, because of its economic importance of the mineral deposits. The research of the area, from a hydrologic point of view, is linked by the setting up of hydrometric stations in hydrographic basins having surfaces over 1000 km2, which, constituted basis for extrapolations at a regional level. tef makes a well-informed analysis regarding the historic of the research of the Trascu Mountains in which, naturally is studied the Ampoi Basin, too.

The activity of hydrometric knowledge upon the hydrographic network of the Trascu and Metaliferi Mountains and, of course, of the Ampoi Basin, took place in two stages, one before 1961 and one after this year. Till 1961 the activity of observations and measurements was regarding only to the records of the levels and these in a limited number of hydrometric stations; sporadically were executed measurements of debits, mostly having an expedition character, in Zlatna Mountains. Observations and measurements, unorganised, were done from ancient times, and they were linked, especially by the use of water in transport and by special hydrologic events: flood and high flood, drying up, etc.

After 1960 was done a network of hydrometric stations having a systematic activity and which were distributed in space taking into account the relief units and they permitted and still permit a global characterization of the zone. The hydrometric stations of whose data were used in this present work are presented in the table 1.


Tab. 1. Hydrometric station whose data were used in the work. Catchment

River Hydrometric station

Distance from the

confluence (km)

surf. (km2)

alt. (m)

Altitude 0 map level (m)

Organize date

Ampoi Iz. Ampoi 42.0 63,0 856 455.203 1980 Ampoi Zlatna 37.6 148 818 403.362 1949 Ampoi Brbn 5.5 556 716 230.152 1961 Vltori Zlatna 9.8 34 915 414.330 1967 Ighiu ard 1.2 105 695 256.941 1983

The hydrometric station Izvorul Ampoiului is the first

hydrometric station in the Ampoi hydrographic basin. It is at 42 km from the confluence of Ampoi with Mure, having a surface of 63 km2 and an altitude of the rod of 455.203 m. In this sector the riverbed is parallel, homogeneous and formed by gravel. The transversal profile is asymmetric, the left bank being better developed.

The Zlatna hydrometric station, the Ampoi River, is one of the oldest stations in the Trascu Mountains. The section of the rod is at 100m downstream from the confluence with the Vltori River. The Zlatna section closes the warning basin Ampoi. The debits measured are influenced by a succession of collecting and deviations in the basins Ampoi, Vltori, Fene, this being why at this hydrometric station is executed a program of observations and measurements necessary for a daily, monthly and annual reconstruction.

Brbn hydrometric station, Ampoi River, was founded in 1961, upstream of the confluence with Mure River, 5.5 km. in the regulated riverbed of the river. The riverbed is formed by medium gravel and sand, the banks being chamfered and stone packed.

Zlatna hydrometric station, Vltori River, is situated in Zlatna, upstream, 8 km of the confluence with Ampoi River. The hydrographic basin is in a carstic relief (approximately 75 % of the surface), this being the reason why the supply of the river is mainly carstic.

ard hydrometric station, Ighiu River, is upstream 1.2 km. by the confluence with the Ampoi River and in downstream 50 m from the confluence elna - Bucerdea.


RESULTS AND DISCUSSIONS The Ampoi Valley comprises 5 sectors different from the

geomorphic and petrography point of view: - The zone between the spring and the confluence with

Trmpoaiele brook, situated on the development area of the Auriferi Mountains, characterized by abrupt slopes and narrow valley.

- Zlatna Depression, develops at the East of the localities Izvorul Ampoiului and Presaca Ampoiului on a length of 15 km, being mainly drained by Ampoi River and by its affluent: Trmpoaiele, Valea Mare and Valea Mic on the right and Vltori, Fene and Bibar on the left. The extinction of the depression is limited upstream by the confluence with the Trmpoaiele brook and downstream by the confluence with the Fene brook, this being also the limit between Trascu Mountains and Metaliferi Mountains.

- The Ampoi narrow path, whose strict delimitation is given by the localities Presaca Ampoiului and Poiana Ampoiului, this part crosses formations having a high degree of compactness and hardness which gives the aspect of narrow path to the limit between Trascu and Metaliferi Mountains - The sector of the depressing basins Mete - Tui, delimited by the localities Poiana Ampoiului and Gura Ampoiului, sector that is the limit between Trascu and Vin Mountains.

- The sector of the inferior basin where Ampoi covers a spread meadow between the Bilag and Mamut Hills.

The geomorphic different of the Ampoi sectors is due to the different geologic evolution, belonging to different paleogeographic zones having various characteristics linked to the bathymetry of the basin, the characteristics of the sedimentation process, the lithologic nature of the sedimentary material, etc.

The paleogeographic evolution of the Ampoi Valley is linked to the evolution of the entire area. In the Zlatna depression zone, the hydrographic organism was carved within the levelling surface Rmei - Ponor. Subsequently the forming state (Pliocene), in Quaternaries the hydrographic network deepened gradually due to the low basic level of the Mure River. Thats why the Ampoi River was forced to cross, epigenetically, the ophiolits downstream of Presaca Ampoiului. Within


the depression there are 4 levels of terrace: the terrace of 60 - 80 m and 30-40m which are to be found in the contact sector to the proper mountain zone, broken up by the lasting hydrographic network as well as by the torrential one. The lower terraces (15 - 20 m and 6 - 10 m) have a larger developing area being the base of the depression.

The Ampoi Valley presents an asymmetry, in the Zlatna Depression Area, the left bank of the Ampoi River being more developed, here being situated the settlements: Zlatna, Fene, Presaca Ampoiului.

The Ampoi River, is the second affluent of the Mure River, from the size point of view (F = 559kmp, L = 60km2), on the right side there is its reception basin beginning with the spring zone under the Pietricica peak (1.144 m) and Dealul Mare (1.044 m) in the Metaliferi Mountains. The hydrographic basin is asymmetrically developed, on the left side being the most advanced and richer flow through the affluences.

The Groha River, in the hydrologic literature Vltori, is the first affluent on the left. The Vltori River gathers the waters from a calcareous relief complex with rich karstic debits. Till 1900 this hydrographic basin was watched through Zlatna hydrometric station.

The Fene River, the next affluent comes down under Negrileasa Mogoului from Metaliferi Mountains. In Piatra Craiului zone it crosses, epigenetically, the calcareous rocks, and afterwards the slope grows suddenly (from 1.5 m/km to 150 - 200 m/km) and there are numerous thresholds and waterfalls. From the hydrographic basin is collected a part of the debits and is transferred to Ampoi River after it was used in the industry of Zlatna town.

Bibar, is the smallest of the effluents but having a rich debit due to its supplying from the karst. In its inferior course it presents a waterfall of about 25m high. As a matter of fact on its road it met calcareous rocks which, instead of avoiding it, the river approached directly through the erosion of the friable rocks.

The Mete River, is developing its hydrographic basin in a region rich in calcareous rocks (especially in Isca Valley). The river has torrential character; it presents the draying up phenomenon, too.


The Ampoia River, is one of the greatest hydrographic underbasins of the Ampoi River; it has its spring in Corabia massif and mostly in Ciumerna Plateau (through Valea Muntelui). Many karstic springs, rich in debits (Toplia, Hldhaia), give it an abundant flow all over the year. After the locality Lunca Mureului it cuts epigenetically the Ampoia Key through the moment bearing the same name.

The Ighiu River, is the biggest affluent of the Ampoi River (F = 105kmp) with which it joints in ard. Its origin is in Ciumerga, in the Ighiu Lake and the springs under this lake (the spring debit - 100l/s). In the ard zone it gets like effluents the elna and Bucerdea Rivers, both having the origin in the spring under the Ciumerna Plateau.

Data regarding the morphometry of the hydrographic basins (length in km., the surface of the hydrographic basins in km2, the average altitude of the basins, the positions of the confluences to the banks) are presented for the Ampoi and its affluences in the table 2.

Tab. 2. Morphometric data regarding the hydrographic basins of the affluences of the Ampoi River; u.c. / upstream confluence.

Waterway Confluence position Length (km)

Surface (km2)

Average altitude (m)

Ampoi right 53 579 700 u.c. - Trmpoaiele 13 65 855

- Trmpoaiele right 6 20 750 u.c. - Vltori 17 107 795

- Vltori left 12 41 982 u.c. - Fene 24 201 763

- Fene left 16 61 934 u.c. - Ampoia 40 366 744

- Ampoia left 15 64 777 u.c. - Ighiu 46 432 739

- Ighiu left 17 107 695 u.c. - elna 13 52 772

- elna left 13 29 670 -Bucerdea left 14 21 630


The hydrologic regime of the surface flow is influenced by the subterranean flow through the full storages, which can supply the surface ones. So, taking into account the geologic structure within the Ampoi basin they can be separated, by the hydrogeologic characteristics, as follows: Prequaternary and Quaternary deposits.

A. Prequaternary subterranean deposits 1. The Complex of the Metamorphic and Igneous Rocks. Parts of this complex are: sericite - chlorite schist, micaschist, paragneiss, etc. They represent the foundation rocks. The geologic structure, the compactness of the rocks doesnt allow the formation of water deposits. The accumulation of water on the clefts, interstices, in small quantity, is due to the rainfalls. The soil, itself, can be a wet reserve depending on its development degree. At the edge zones there can appear springs, even permanent ones. The category of igneous Mesozoic rocks is present in the Ampoi hydrographic basin, left slope, where the basalt, diabase, are less aqueous. 2. The Calcareous aquatic Complex. It consists of limestone as plateaus, storages covered by actual vegetation, all of Jurassic age. The karstic zone represents an important source for the subterranean waters whose existence and evolution is determined by the geologic characteristics of the limestone and of the environment factors and the chemistry of waters. 3. The Cretacic aquatic Complex consists of a series of geologic formations, known in the literature of specialty as the Fene, Cbeti, Valea-Dosului, Mete, Prul Izvorului, Valea lui Paul and Brdeti strata. The main stones are formed by conglomerate, grit stones, marls, gravel (detritic cemented rocks, the majority having calcareous cement). Because of the tectonic structure, complicated by wildflisch type, the accumulation of water is possible only in the fissures, which affects mostly the conglomerate. 4. The Upper Paleocene Complex is developed only in the Bilag Plateau, the inferior course of the Ampoi River, where prevails the conglomerate, the sandstone, the marl - clay in which there werent found any water reserves.


5. The Pliocene aquatic Complex is developed flanking the Cuaternarium storages of the Mure River, which comes in through the holes as Ampoi River. The geologic storages are formed by sands, marl clay, gravel in which the possibilities of water accumulation are limited.

The subterranean contribution, within the Ampoi Basin, has been studied as a result of the inventory of the debits of each of the springs within the basin. Statistically, the results of the field research regarding the debits of the springs in the geologic complexes quoted above are as follows: - taking into account its debit, no matters the position:

- big, over 20l/s: Iezer (205l/s), Toblia (43l/s), Piatra Caprii (20l/s) - medium, between 19,9-5l/s: Feneana, downstream of the chalet

(10m/s) - under 0,5l/s (in this category falls the majority of the springs, from

which the most important are): Coasta Oprit, Feneana downstream of the key, Vlae, etc

- taking into account how they reach the surface - descendent - Vlae, etc. - taking into account the rock from which they appear to the daylight:

- limestone: Iezer, Piatra Caprii, - cretaceous flysch: Coasta Oprit, Castel.

- terrace springs: Vlae. - springs descendent from debris: Naiba.

B. Quaternary subterranean storages From a geologic point of view the Quaternary storages are

made up from alluvial-proluvial materials, gravel and sands with intercalations of silty sands, which form an aquatic stratum with extension into the meadow storages of the effluents. The hydrogeologic map of the Alba Iulia zone shows through the hydroisohipses the morphology of the hydrostatic level, the direction of the underground draining, the link between the surface waters and the underground ones (Fig. 1).


Legend 0 50 0 1. 00 0 1.5 0 0 k m

225

220

230

235

24024525

0

255

260

265

245

215

Ampoi r.

H .St.A lba Iulia

H.St.Barabant

H.St.Sard

ALBA IU LIA

Micesti

B arabant

Sard

Tel n

a vIghiu v .

B I L A G Plateau

A P U

S E N I M

ou n tains

S E

C A

S E L

O R

Plat

eau

Mures

R .

.

hydroizohipsesprings s pring line

section w ith hydrologic al conection

lim ite of geomophological unit s

locality

hydrometric station

Fig. 1. Hydrogeological map - Alba Iulia area.


The water flow The liquid flow represents the most important hydrologic

characteristic of the hydrologic basins; it expresses the water resources carried by the rivers. For the characterization of the flow as average, maxim or minimum aspect there have been analysed all the hydrometric stations regarding the evolution of the debits and their repartition in the territory.

A.The Rivers Supply The particularities of the flow of the liquids and, generally of

the hydrologic elements of the Ampoi River are determined by the kind of the supply source and the character of its variation along the year. The most important supply sources are from: 1) The rainfalls - are the basic element of the evolution of the debits of the hydrographic network (it dominates from a percentage and quantitative point of view all the other sources). During a year the maxim value is touched at the end of winter and the beginning of spring, in the same time with the intensification of the winds (February - March), when the snow melts. The most reduced values are produced at the end of summer and at the fall (August-September) when the underground supply prevails. 2) The calcareous storages - represent an important element of flow through the special capacity of storing of the debits in drains and big holes as a result of the draining from the rainfalls or snow (as a result of melting). 3) The no calcareous sectors - is the most developed source, except the first one, and is the first source of waters. It develops from East to West on the calcareous band and comprises the courses of the following effluents: Ampoi, Fene, Bibar and Ampoia.


B. The Daily Flow Regime The daily flow is under the direct influence of the weather

factors: rainfalls and snow, the existence and the structure of the snow stratum, the evolution of the air temperature, the relief, etc. Easy to be noticed the oscillations of the daily flowing are remarked in springtime and at the end of winter when the daily thermic modifications cause variations of the debits (and levels) of the rivers by increasing during the day and decreasing during the night. In the rainfalls period, generally beyond 2 l/m, having as background a high wetting degree, taking into account the time of concentration in the riverbed, the oscillation of the debits conditioned by the nature, intensity and duration of the rain, of the water quantity and the rhythm of the

Fig. 2. Relation between carst /noncarst flow.

10

20

30

40

50

I II III IV V VI VII VIII IX X XI XII

10

20

30

40

50

I II III IV V VI VII VIII IX X XI XII

a.

b.

a. Hydromethric station Zlatna, Valtori river - limestoneb.Hydromethric station Izvorul Ampoiului, Ampoi river - no estone

Q mc/s

Q mc/s

nlim


draining of the underground accumulations. The daily hydrographs present, in the mountainous zones high oscillations in the hydrographic basins such as Izvorul Ampoiului (less than 60 km2) due to the low concentration time, the specific weather factors for the high zones, of the relief taking into account the hydrometric stations from the downstream end of the hydrographic basins where the genetic factors act with low intensity. To all these is added the attenuation regime in the riverbed, the flow not having a torrential character as in the mountainous units.

C. The Monthly Flow Regime The monthly evolution of the flow has been watched as crude

as well as a percentage value taking into account the total flowing. There have been calculated the module coefficients (Tab. 3). The highest average flow is in April, over 15 % of the cases, and the lowest in September. In September-October there is a slight uniformity in the distribution of flow due to the supply from the underground strata.

Tab. 3. Monthly and seasonal average - percentage value.

H. st.

Debits (m3/s) Month

The factors who influences the average monthly and seasonal flow

1. 6.20 2. 6.44 3. 6.32 4. 5.72 J

a

n

u

a

r

y

- the snow doesnt participate directly to the flow phenomenon, the supply being done from the underground.

1. 7.90 2. 10.5 3. 9.88 4. 9.12 F

e

b

r

u

a

r

y

- because of fhn activity increase the flow values, - the high flood begin in the second half of month,

1. 20.20 2. 16.62 3. 14.73, 4. 12.77

M

a

r

c

h

- the stress of the snow melting determines the increase of the flow values,

1. 16.50 2. 15.60 3. 15.58 4. 15.36

A

p

r

i

l

- the melting of the most part of the snow,


1. 18.60 2. 11.42 3. 11.67 4. 12.95

M

a

y

- the flow is still high but lower than the previous one,

1. 9.10 2. 11.58 3. 11.20 4. 14.15

J

u

n

e

- it continues the tendency of flow lowering, - high values will be only in the hydrographic basins with karst supply,

1. 5.10 2. 8.34 3. 8.34 4. 7.87

J

u

l

y

- due to the heavy rains there are the highest percentage values,

1. 3.6 2. 3.71 3. 4.17 4. 4.67

A

u

g

u

s

t

- the decreasing of the rainfalls stress the diminution of the flow,

1. 1.6 2. 2.80 3. 3.37 4. 3.37

S

e

p

t

e

m

b

e

r

- there is the lowest flow from the internal supply,

1. 2.2 2. 3.12 3. 4.30 4. 3.49 O

c

t

o

b

e

r

- the rains in autumn increase the flow values,

1. 3.0 2. 3.70 3. 4.66 4. 4.13

N

o

v

e

m

b

e

r

- the rainfalls lead to the increase of flow,

1. 4.0 2. 6.17 3. 5.78 4. 6.40

D

e

c

e

m

b

e

r

- the rainfalls and snow as well as the wind lead to increases of the flow values,

Hydrometric stations: 1. Izvorul Ampoiului, 2. Zlatna, 3. Brban, 4. Zlatna/Vltori


Conclusions: the flow fallows faithfully the evolution of the rainfalls. In the months with rich rainfalls, March-June, the flow has the highest values.

D. The Seasonal Flow Regime The evolution of the seasonal flow is conditioned by the

combination of the supply sources of the hydrologic organisms. The winter (December-February) is characterized by snow,

which remains stocked. The supply is made from the underground (calcareous or not). The highest values are of 23 % at Zlatna and Izvorul Ampoiului. The installation of the winter phenomena has as an effect the dislocation from the flow of an important water quantity.

The sprig (March-May) represents the richest flow in the entire year (over 40 %) and it is done under the influence of the snow melting and the evolution of the rainfalls. The highest values were recorded at the Izvorul Ampoiului station (55.3 % from the annual flow) and the lowest ones at the Zlatna, Vltori stations (41.1 %).

The summer (June-August) the regime of the flow is influenced by the increasing evolution of the temperature, the development of vegetation, which lead to the decreasing of evaporation. To these is added the lack of rainfalls, all leading to the decreasing of the flow.

The autumn (September-November) is characterized by the lowest flow of the seasons. Actually only the underground supply forms the flow supply. The highest values are of 12.3 % at Brban and the lowest ones at Izvorul Ampoiului.

As regarding the months, the lowest values are in September (1.6 % - at Izvorul Ampoiului, 2.8 % at Zlatna)

As a conclusion the supply process of the flow: the highest monthly flow is in April when having as a background the snow melting, there are the most rainfalls, too, the lowest values of the flow were in the winter time when the rivers ran dry totally (Ighiu, Ampoia).


The Regime of Average Flow The average flow of the waters characterizes the richness in

waters of the hydrographic basins. The average flow for many years is determined taking into account the annual average debits as a result of the processing of the hydrometric observations and measurements from the previous years as an average of the debits in the most years.

The average value of the average flow depends on the average values in more years of the rainfalls, evaporations, by the hydro and weather components of the geographic coat, by the vegetation cover degree, by the soil, the slopes etc. Taking into account the multiannual average values (Tab. 4a) has been done the map of the specific average flow in Trascu and Metaliferi Mountains.

Tab. 4a. Monthly and annual average debits value.

Debits River Hydrometric station

F km2

Hmed m Q m3/s q l/s km2

Iz. Ampoiului 60.0 940 0.679 11.3 Zlatna 148 818 1.40 9.46

Ampoi

Brban 556 625 4.01 7.21 Vltori Zlatna 34 915 0.445 13.1 Ighiu ard 100 725

E. The Regime of Maxim Flow The maxim flow represents the most important moment of the

water flow through the produced effects. The knowledge of the maxim flow, its development in time raises problems linked to the fact that there werent done measurements for very high levels of the waters from objective reasons. Excepting the high flood in 1970, which werent recorded at all hydrometric stations, the other ones in the years 1975, 1979, 1981, 1995 considered to be very important for the calculation of the maxim debits, were recorded. From the table 4b, one can reach to the conclusion that the highest debits recorded at the hydrometric stations were as a result of the rainfalls in the hot season, in July.


Tab. 4b. The frequency of the high flood producing - maxim debits achieved.

Qmax. achieved (mc/s) River Hydrometric station

F km2

H med. value date

Iz. Ampoiului 60.0 940 23.5 III Zlatna 148 818 116 VII Ampoi Brban 556 625 244 VII

Vltori Zlatna 34.05 91 48.5 VI; VII

F. The Regime of Minimum Flow The calculation of the minimum flow, based on statistics, was

done by processing the observation data for a total of 15 years. The analysis of the minimum debits (see the table 5) can not be done correctly if there isnt taken into account the existence of the uses which, influences the minimum flow. From the investigations in the field, one can reach to the conclusion that the most influenced station is the Zlatna station, as a result of the use of the water for industrial purposes.

G. The Regime of Flow from Alluvial Deposits The flow from the alluvial deposits is generated by the erosion

phenomenon on the slopes and by the elementary hydrographic network. In their turn the erosion phenomena, their quality and distribution in space and time is under the condition of a series of specific factors of the hydrographic basin: pedology, relief, the character of the rainfalls, the temperature, etc. To all these factors there are added the anthrophic ones, which can contribute to the modification of the sum of the alluvial debit. The data regarding the values of the solid flow in suspension and of the solid debits are presented in the tables.


Tab. 5. Minim debits with the probability of producing - hydrologic stations in Trascu and Metaliferi Mountains.

Maximum debits from different probability Hydrometric

station

F

(

k

m

2

)

H

m

e

d

.

(

m

)

Q

0

(

m

3

/

s

)

L / Z 80% 90% 95% 90%

M 0.038 0.022 0,014 0,012 Iz. Ampoiului (Ampoi River) 63 856 0.667 D 0.015 x x x

M 0.032 0.018 0,012 0,010 Zlatna (Vltori River) 34 915 0.428 D 0.010 x x x

M 0.08 0.045 0,03 0,025 Zlatna, (Ampoi River) 148 818 1.40 D - - - -

M 0.270 0.16 0,10 0,08 Brban (Ampoi River) 556 716 3.93 D 0.10 0.065 0,05 0,04

M 0.036 0.02 0,012 0,010 Fene 61 934 0.52

D 0.01 x x x M 0.03 0.015 0,01 0,008

Ampoia 54 777 0.43 D 0.008 x x x M 0.048 0.030 0,020 0,015

Ighiu do

w

n

s

t

r

e

a

m

o

f

A

m

p

o

i

R

.

c

o

n

f

l

u

e

n

c

e

107 695 0.80 D 0.020 0.01 x x

Q0 - multiannual average debits, M - monthly value, D - daily value, x - litre order value, - anthrophic influence

The Ampoi hydrographic basin, developed on different physic

and geographic made up from a lot of rocks generates a great diversity of the solid flow. The observations and the measurements done at the hydrometric stations, demonstrate that there is a link between the hydraulic and morph metric parameters of the riverbeds. The increase of the debits has as an effect the reduction of the porosity, the amplification of the slopes and of the moving speed in the riverbed. After the high flood the water debit comes back to the previous situation. The coming back to the previous situation reflects certain equilibrium among the alluvial supply, laying and giving up the alluvial on the riverbed to the flow, depositing alluvial in the downstream.


This is the case of the hydrometric stations Izvorul Ampoiului. The Ampoi River develops its course over hard rocks having a reduced friability, such as calcareous rocks, volcanic rocks and metamorphic ones. In these sections the variation is not important the geologic composition is the dominant factor in the achievement of the stability of the riverbed. The phenomenon of deepening of the riverbed is specific for all the hydrometric stations placed in the inferior courses, depressions among the mountains (Zlatna Depression). CONCLUSIONS

The water flow (average, minimum or maximum) is under the direct influence of the weather, of both physic and geographic factors of the Trascu and Metaliferi Mountains. It is emphasized a rich flow in the high zones which, is reduced due to the development of the basin surface in the case of the medium flow. The maximum debits are achieved, especially due to maximum rainfalls, the greatest values being achieved in summertime. The minimum debits are influenced by a rich karstic flow, especially in the central calcareous sector, which have as an effect the maintaining of minimum debits all over the course of the river, although in the inferior courses the infiltration of the own alluvials is prevalent.


SELECTIVE REFERENCES 1. Bleahu M., 1974 - Morfologia carstic, Editura tiinific,

Bucureti. 2. Diaconu C., 1961 - Unele rezultate ale studierii scurgerii minime a

rurilor RPR, Studii de hidrologie, vol.XXIV, Bucureti. 3. Ianovici V., Giuc D., Ghiulescu T.P., Borco M., Lupu M.,

Bleahu M., Savu H., 1969 - Evoluia geologic a Munilor Metaliferi, Editura Academiei RSR, Bucureti, 741 p.

4. Luduan N., 2002 Zcminte i poluare pe Valea Ampoiului, Editura Aeternitas, Alba Iulia, 196 pp.

5. Mutihac V., Ionesi L., 1974 Geologia Romniei, Editura Tehnic, Bucureti, 612 p.

6. Mutihac V., 1990 Structura geologic a Romniei, Editura Tehnic, Bucureti, 418 p.

7. Mutihac V., Startulat M. Iuliana, Fechet R. Magdalena, 2004 Geologia Romniei, Editura Didactic i Pedagogic, Bucureti, 225 p.

8. Posea G., 2002 Geomorfologia Romniei, Editura Fundaiei Romnia de Mine, Bucureti, 445 p.

9. Preda I., Marossi P., 1971 Hidrogeologie, Editura Didactic i Pedagogic, Bucureti.

10. teff V., 1998 Munii Trascu. Studiu hidrologic, Studii i cercetri, hidrologie, 66, 246 p., Institutul Naional de Meteorologie i Hidrologie, Bucureti.

11. Ujvari I., 1959 Hidrografia RPR, Editura Academiei Romne. 12. Zvoianu I., 1977 Morfometria bazinelor hidrografice, Editura

Academiei RSR, Bucureti. 13. x x x, 1971 Rurile Romniei. Monografie hidrologic, Editura

IMH Bucureti. 14. x x x, 1954 Scurgerea medie specific a rurilor din RPR, DGH,

Bucureti.


CONTRIBUTIONS TO THE PETROGRAPHYC STUDY

OF THE MAGMA ROCKS FROM THE ALMAU MARE (ALBA COUNTY) - TECHEREU -

TEAMPURI VALLEY (HUNEDOARA COUNTY) AREA

Viorel Ciuntu

Natural History Museum, 1 Cetii St., Sibiu, RO - 550160.

REZUMAT Zona Almau Mare - Techereu - Valea teampurilor, acoper o arie de 27 km2 i este situat n partea de nord vest a bazinului Neogen Zlatna, n zona axial a Munilor Metaliferi. Aceast arie este delimitat la nord de Dealul Fericelii, la vest de valea teapurilo, i la sud i sud est de valea Techereu. Partea superioar este numit valea Almaului. Limita de est a zonei studiate este dat de localitile Almau Mare i Brdet. Produsele vulcanice ofiolitice din zona studiat se gsesc n aria Techereu - Valea teampurilor. Acestea aparin fazei de evoluie secundar a magmatismului bazic i sunt reprezentate de diabaze augitice, dolerite i paleobazalte. Rocile rezultate datorit magmatismului subsecvent tardiv n zona Almaul Mare - Techereu - valea teampurilor sunt reprezentate de andezite de Faa Bii, riolite de Bia i andezite de tip Barza. n lucrarea de fa sunt prezentate caracteristicile mineralogice, structurale i naturale a acestor produse eruptive, din aria studiat care aparine Munilor Metaliferi. Key words: Metaliferi Mountains, mesozoic rocks, neogene rocks, petrography.


INTRODUCTION The Almau Mare-Techereu- teampuri Valley zone with an area of approximately 27 km, is included between the following geographic coordinates: 4610and 46 northern latitude and 2045 and 21 eastern longitude. The area explored, situated in the north-west side of the Zlatna neogene basin, in the axial zone of Metaliferi Mountains, is delimitated at north by the Fericelii Hill, at west by the Steampuri Valley, and at south and south-east by the Techereu Valley, of which superior flow appears under the name of Alma Valley. The eastern limit of the researched area is given by the localities Almau Mare and Bradet.

RESULTS AND DISCUSSIONS The initial neokimmerian magma from the Techereu-teampuri Valley The ophiolitic volcanic products from the Techereu-Steampuri Valley are considered to belong to the second phase of evolution of the basic magmatism. These products appear developed in area under the form of lava flow and pyroclastic rocks.It is interesting to remark the pillow-lava aspect, characteristic of some ophiolitic rocks which are found in Techereu Valley and teampuri Valley. Although, the volume of these products, from a magmatic activity with numerous explosive sequences, reported to the Metaliferi Mountains area, it is small towards the amount of rocks generated by the first phase of this magmatism (prekimmeric phase), but in the area explored by us these become predominant. The whole ensemble of ophiolitic rocks, corresponding to the neokimmerian phase, occupies the southern and western part of the researched area, on the teampuri Valley and Techereu Valley. This complex enters also in the central part of the area, on the Bodii Valley and on the Mr Beck (upstream the Techereu village, unlike the Bodii Valley, which is to be found downstream the village).


The petrographyc characteristics of ophiolitic rocks from the Almaul Mare-Techereu-teampuri Valley zone After the macro study and, especially, of the microscopic one, we end up differentiating a series of types rocks characteristic to the neokimmeric phase of the initial magmatism, types of rocks which developed mostly in the researched area. In this respect we differentiated three types of rocks that are major too: diabase augite, dolerits and melaphirs or paleobasalts. Diabase augite This type of rock forms small intrusions in the basic rocks in the area, forming a developed massive up stream the Techereu village, on the Mr Beck, affluent on the right side of the teampuri Valley. Here, the dibasic rock appears altered, having an earthy aspect, and a grayish -black to intense green colors. Macroscopic, one can distinguish that in the mass of the rock appears, very well developed phenocrystals of augite, next to calcite tonsils, sometimes of few millimeters. The augite, in comparison with the mass of the rock often altered and weathered appears in fresh shape, under the form of short-prismatic crystals, of black color, which often form crystal aggregates or macle ones. The dimensions of these crystals are within 5 to 20 mm in length and 3 to 10 mm in thickness. The short prismatic habitat is given by a short number of crystallographic forms, such as: pinacoid-(100), monoclinal prism-(110), clinoprism-(011) and rarely forms of orthopinacoid-(101). Macroscopic one can notice that the augite forms, one of the main components of the rock, appearing in proportion of 17.6 % from the mass of the rock, next to which we encounter some other minerals, such as olivine (11.9 %), plagioclase feldspar, which along with the microlyth form approximately 15 % from the mass of the rock. The fundamental mass of the rock, in most of its part profoundly altered constitutes approximately 45-50 % from the entire rock. The presence of these minerals and the way they appear in the rock show that it is a diabase, of whose structure is a porphyritic ophitic one, sometimes interserthal and having a not directed texture.


Microscopic, the augite forms aggregates of intermission of two-three crystals, as well as juxtaposed macle of two specimens of pinacoid face (100). The augite crystals show an obvious cleavage (86). A big part of the augite crystals feature zones of structure, due to the rhythmic variations, sometimes even turbulent ones, of the chemical composition. These variations suggest the idea that in the crystallization process there were very mobile forming conditions and, even, hectic, due to which the augite crystal germs, permanently supplied with fresh material, were able to grow, generating the phenocrystals having the known dimensions. The characteristic optic proprieties, given by the extinction angle (44), the highly interference colors, in general green-bluish of 3rd degree, and brown-reddish of 2nd degree, as well as the obvious relief, given by a high birefringence, attests the presence of augite in the diabase of the Techereu-Mr Beck. Another mineral, which takes part to the formation of the rock, is plagioclase fedspare. This can appear as a phenocrystal, seldom, as well as a microlyth, most of the time. These crystals interpenetrate, forming intersections, in which the crystals of other minerals are evolving (olivine, magnetite, and sometimes augite). These fedspares appear, in general, quite fresh, in comparison with the fundamental mass of the rock. After the microscopic analysis, we could establish that the plagioclase fedspares, represented in this diabase has an andesinic composition (35 % An). Next to augite and plagioclase, in the diabase rock from Techereu-Mr Beck, appears the olivine, too, most of its part being altered, which, together with the augite, forms approximately 29.5 % of the mass of the rock. As mineral accessories appear the magnetite and leucoxene, as a result of the transformation of the melanocratic minerals, especially of olivine, and, in a less quantity of the augite. As a result of the physical-chemical transformation of the rock, the component minerals alteration as well, giving birth to a whole series of minor minerals: chlorite, calcite, serpentine, limonite, and rarely clay minerals.


The dolerite This type of rock appears well developed, only on the Techereu Valley, in Ordaul Hill. Reported to the entire surface of the explored area, this dolerite appears as a subordinate type of rock. From a microscopic point of view, it doesnt differentiate much from other basic rocks from the area, having a black-greenish color and a not such a consistent aspect. Microscopic, this type of rock shows an interserthal porphyric structure, and a massive texture. The phenocrystals are formed from plagioclase fedspares, which appear in a higher quantity that the microlites. These phenocrystals form crystals aggregates generating intersections, in which, mainly, melanocrate minerals develop (augite, olivine, rarely, hipersten). The fundamental mass of the rock is, often, transformed, and in which one can easily distinguish fedspares microlites. The melaphyrs or paleobasalts These rocks constitute the predominant geographic type in the researched area. They appear well developed on the Techereu Valley, on the teampuri Valley and on the Bodii Valley. These rocks are considered to be pale basics (melaphyrs), due to their mineralogical composition, as well as to their structure and texture. Like the diabases and the dolerites in the area, the melaphyres appear also altered, having an earthy aspect and a black-greenish color to intense green. The melaphyres on the Techereu Valley present a pylotaxitic porphyric structure and a vacuolar-amydaloidal texture. The phenocrystals are represented through plagioclase feldspar by the composition of the andesite (32 - 35 % An) and through pyroxene phenocrystals, mostly augite, as well as olivine, in a smaller part. The melanocrates minerals appear most of the time, transformed, being substituted pseudomorphicly by the neoformation minerals, especially chlorite and calcite. An interesting fact is the presence in the vacuolar of the rock of the chalcedonies and zeolites next to which appear the argilitics minerals and iron oxides.


The Bodii Valley melaphyres are generally greenish-greyish, with numerous cracks and diaclases. Microscopic, it features a basaltic aspect, given by the ophitic porphyric structure and amydaloidal texture. Phenocrystals are represented by feldspar plagioclase with the andesine composition, rarely of bytownite. The augite and crystal remains of olivine accompany these phenocrystals. The profound alteration of the mass of melaphiric rocks led to the transformation of the mineral components of the rock, and result some minor minerals, such as: chlorite, caolinite, zeolite, silicon and iron oxides. The teampuri Valley melaphyres, does not differ, in general from other paleobasaltics from the area, only that here it appears more greenish, due of an intense transformation of the melanocrate minerals. The rocks from this part of the area present the same porphyry ophitic structure, sometimes intergranular, and vacuolar amygdaloidal texture. The plagioclase phenocrystals (65 - 68 % An) constitute the main components of the rock, next to which appear the rhombic pyroxenes, especially the hypersten, and in smaller quantity, the augite and olivine, altered in most of its part. A big part of the fundamental mass of the rock is transformed, being composed from an entire series of minerals of newly formatted parts, on the behalf of primary minerals. In this way appear: the clay minerals (caolinite), chlorite (chlinochlor, prochlorite), minerals belonging to the antigorite group (serpentine) epidote, calcite, calcedonite, as well as sericite, but in an entirely subordinate quantity. From what we have seen so far, a conclusion can be drawn, that the main rock types characteristic to the neokimmeric phase of initial magmatism, which is to be found in the researched area, have some mutual features such as: a porphyric structure and a not oriented or vacuolar - amygdale texture; the phenocrystals that predominate are the plagioclase feldspar, in general by the andesine composition, and pyroxene, especially the monoclinic ones, specifically: the augite; the main rock types features intense phenomena of transformation, which affect the primary minerals from the rock, as well as the fundamental mass of the rocks, resulting a series of minor minerals; as a form of a deposit, it appears mostly under the form of lava flow and rarely as agglomerate or other types of explosive products.


Regarding this aspect of the volcanic agglomerate, we must mention the fact that on the teampuri Valley, especially near the Techereu village, these become predominant, being interlaid between the Cretaceous sedimentary deposits. The cement of these agglomerates is of cineritic nature, and the constitutive elements are, most of its part, diabase and paleobasalts (melaphyres). Also at these effusion products one can notice an intense process of physical-chemical alteration of epimagmatic nature, hydrothermal transformations, forming, mainly, the calcite and zeolites, which deposed themselves on the contact zone between the constitutive elements of agglomerates and cineritic cement. Beside these agglomerates, on the teampuri Valley appears a series of cineritic products, having a bush aspect which like the agglomerates, are included in the clay-marl sediments and sandstone of inferior Cretaceous (Barremian-Aptian). Reported to the researched area, the cineritic pirocastic products are more developed than the volcanic agglomerates, and sometimes, even than the basic lava flows. The subsequent belated magmatism A very important role in characterizing the magmatism evolution from the Metaliferi Mountains has the magmatic manifestations that took place in Neogen. These manifestations, with magnitude and different areas, constitute what in the geologic literature in our country is known under the name of subsequent belated magmatism. The fact that to a series of neogen magma rocks are linked many deposits and metaliphere minerals (Au, Ag, Te, Pb, Zn, Cu, Hg, etc) has made this magma rocks to be thoroughly explored under mineralogical aspect, such as: from the petrography point of view, as well as from the genetics, the chemical and the genetic of the metals point of view. Special researches regarding the subsequent belated magmatism from the Metaliferi Mountains area started, in a systematic way, even from the second half of 19th century, by some of the geologists from abroad, such as: F. Richthofer, Fr. Hauer, G. Stache, J. Szadeczky, K. Papp, etc.


In the period between the wars the research activity regarding the tertiary magmatic manifestations in the Metaliferi region was continued by some Romanian geologists, from the Geologic Institute, such as M. Ilie, T.P. Ghiulescu, M.Socolescu, D. Giuc, V. Ianovici, N. Petrulian, which elaborated works of a real scientific value, regarding the evolution of the neogen magmatism, as well as regarding the genesis of the metals phenomenon, linked to that magmatism. Referring to the evolution of the subsequent belated magmatism some works must be mentioned: M. Ilie (Lge des roches effusives dans les regions auriferes des Monts Apuseni) and T. P. Ghiulescu and M. Socolescu (Etude geologique et miniere des Monts Mtaliferes -1941), in which the authors considered that the evolution of this type of magmatism had taken place in four distinct phases. If, until the year 1960, the Romanian geologists were not completely agreeing to an evolution of subsequent tardy magmatism in three phases, today this conception regarding this magmatism evolution in the Metaliferi Mountains is unanimously accepted. Interesting and valuable studies were written lately by a series of geologists such as M. Borco, Constantina Stanciu, G. Cioflica, etc, studies in which the authors dealt with some aspects regarding the genesis of the metals and the hydrothermal transformations about the places of some rocks (especially andesites), in the Metaliferi Mountains area, especially in their central-eastern part. Nowadays, a great part of the studies and the researches in the Metaliferi Mountains, regarding the neogen magmatism and the phenomena associated to it, are reproduced, in a systematic way in the large work Evoluia geologic a Munilor Metaliferi (The geologic evolution of Metaliferi Mountains), edited by a group led by the academic dr Virgil Ianovici. The evolution of the subsequent tardy magmatism in the Metaliferi Mountains Besides the first two phases of subsequent magmatism in the Metaliferi Mountains, such as subsequent precocious magmatism and the epeirogenetic one, the third and the last phase, the subsequent tardy magmatism, comes to complete the geologic architecture of the Metaliferi Mountains.


After a long period of the rising of the earth crust in which a big part of the previous formed relief was erodeted the magnetic activity is started over again in Badenian, through the manifestation of a volcanism of andesite and riolit type, with numerous pyroclastic products. The neogen volcanism (Badenian-Sarmatian) had a strong explosive character generating important quantities of cinerite, pyroclastic rocks and lava constituting numerous volcanic devices, especially volcanoes and volcanic chimneys. The maxim development of subsequent tardy magmatism, in the ditch of the Metaliferi Mountains, it is to be found in its central zone, in the gold-bearing quadrilateral. From the petrochemical point of view a big resemblance is made between the products of this phase and of the epiorogenic phase, this leading to the idea the petrochemical fund could have been the same form both of the magmatic phases. In the ditch of the Metaliferi Mountains, this last phase of neogen magmatism took place in the tardecinematics phase of alpine cycle. The most violent sequence of neogen magmatism is characterized by a genetic phase of the metals, a very well developed one, of mezzo- and epithermal nature. The mineralization generated by this intense hydrothermal phenomenon is mainly of a gold and silver nature, with tellurium and native gold, which in some places, deeper, passes to a mineralization dominated by lead-zinc or cooper. To the end of these mineralized zones another zone is developed, of cinnabar mineralization, of epithermal type, in which the cinnabar is often associated with native gold, arsenic minerals and antimony, also epithermal. Linked to the flow of hydrothermal solutions through the neogene magmatic rocks, appears the transformation phenomenon, transformation that took place in more phases. Regarding the evolution of the eruption phases from the subsequent tardy magmatism it is necessary to present the opinions of some of the geologists, which dealt with this issue.


M. Ilie acknowledges the existence of four phases of eruption during the neogen magmatism, as follows: phase I of eruption-the effusion phase of rhyolites, which took place during the 1st Mediterranean (antebadenian at Roia and acvitanian at Zlatna); phase II of eruption-the effusion phase of andesites with the pyroxenies between the Mediterranean 1st and 2nd; phase III of eruption-the effusion phase of andesites and postbadeniene dacites; phase IV of eruption- the effusion phase of pliocene basalt. Linked to the conception of M. Ilie regarding the evolution of the neogen volcanism, must be mentioned the conception of T. P. Ghiulescu and M. Socolescu, which does not differ from the first one. In this respect, the two geologists admit a tertiary volcanic activity, also in four phases, as follows: phase I of eruption putting the Faa Bii andesites in the place and of Bia riolites; phase II of eruption putting in the place the Cinel dacites; phase III of eruption where the Barza andesite was put in the place (in Brad-Scrmb basin) and Breaza pyroxene andesite (in Zlatna-Almau Mare basin); phase IV of eruption with the forming of Detunata basalt. Unlike these three geologists opinions, in th

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Ao Xiii, 1-2, 2006 Papers