Gas Analysis v2 Powell-2010-StanfordGW

document.xls 04/07/2023

-30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 -8-7.0

-6.5

-6.0

-5.5

-5.0

-4.5

-4.0

-3.5

-3.0

-2.5

1

36

7

1

2

3

4

567

1

2

3

4

5

6

7

FT log (rCO2) + 4 log (rH2) - log (rCH4) (WG 1980)

log

(rH

2S

) (

WG

19

97

)


-30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 -8-7.0

-6.5

-6.0

-5.5

-5.0

-4.5

-4.0

-3.5

-3.0

-2.5

1

36

7

1

2

3

4

567

1

2

3

4

5

6

7


log

(rH

2S

) (

WG

19

97

)


-30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 -8-6

-5

-4

-3

-2

-1

0

1

2

3

4

6

7

1

2

3

4

5

6

7

1

2

3

4

5

6

7


log

(rC

O2

) (

WG

19

97

)


-30 -28 -26 -24 -22 -20 -18 -16 -14 -12 -10 -8-6

-5

-4

-3

-2

-1

0

1

2

3

4

6

7

1

2

3

4

5

6

7

1

2

3

4

5

6

7


log

(rC

O2

) (

WG

19

97

)


-28 -24 -20 -16 -12 -8-13

-12

-11

-10

-9

-8

-7

-6

-5

-4

1

7


HS

H 3

log

(rH

2S

) -

log

(rH

2)

(W

G 1

98

0)


-28 -24 -20 -16 -12 -8-13

-12

-11

-10

-9

-8

-7

-6

-5

-4

1

7


HS

H 3

log

(rH

2S

) -

log

(rH

2)

(W

G 1

98

0)


-10 -9 -8 -7 -6 -5 -4 -3-6

-5

-4

-3

-2

-1

0

1

2

3

4

1

2

3

4

5

6

3

4 1

2

3

4

5

6

log(CO/CO2)

log

(CH

4/C

O2)

GRID RH = -2.8


0 1 2 3 4 5 6 7 8-2

-1

0

1

2

3

4

5

1

1

2

3

4

5

6

7

8

9

10

11

1

2

1

2

3

4

5

6

7

8

9

10

11

log(CO2/Ar)

log

(H2

/Ar) GRID RH = -2.8

CO2-H2S-NH3 Ternary


1

2

3

4

2

3

1 4

1

4

2

34

CH4 - CO2 - H2S Ternary


2

34

1

2

3

4

5

67

8

9

10

11

12

1314

15

16

17

18

3

4

4

123

4

5

6

7

89

2

3

6

7

1011

1415

181 4 5 8 9 12 13 16 17

1

4

5

8

9

12

13

16

17

Chart RH = -2.8

Reservoir Temperature

200

N2 - CO2 - Ar Ternary


21

234

5

67

8 9

10

11

12

13

141516

17

18

1

1

2

2

34

23

67

1011

1415

181 4 5 8 9 12 13 16 17

1

4

5

8

9

12

13

16

17

N2 - He - Ar Ternary


1

2

3

4

567

8 9

10

11

12

13

141516

1718

1

2

31

2

2

34

23

67

1011

1415

181 4 5 8 9 12 13 16 17

1

4

5

8

9

12

13

16

17

Gas data input sheet CCH Ternary

CH4CO2H2S

RH

initial reservoir T

Total noncondensible gas

Sample Name Source Type Date Sample Label G/S x10^6Ohinemutu fum 3 1000North Kuirau 5 1000000QE Hospital 8 18600South Kuirau 12 1000000Sulphur Point 15 280000Polynesian Pool 16 13000Well M9 well 22 2200Ngapuna pool pool 23 12000Ngapuna river stream 23 1000000Placemakers 26 54000Lake Rotokawa lake LR 710000Hinemoa's Pool pool HP 1000000Towntalk Motel 28 22000Race Course 30 900Mushroom Farm 36 209000Arikikapakapa 38 1000000Roto-a-Tamaheke 40 210000Whakarewarewa 41 550000Pohutu Mound 42 8700Ngararatuatara 43 2500FRI well well 44 5600

Results of mm/100mH2O Conversion TableG/S 10^6

1 111102 03 04 0

Copy data into columns inside bold box. Input values are in black, fixed headings and calculations are in

blue.

This will be the label plotted on the

charts

Input one of these values. Percentages are decimals (e.g. 1.75% = 1.75)

mole percent

weight percent

5 06 07 08 09 0

10 011 012 013 014 015 016 017 018 019 020 021 022 023 024 025 026 027 028 029 030 0

Input mm/100mH2O Conversion TableSample Name Source Type Date Sample Label

123456789

10111213141516171819

2021222324252627282930

CCH Ternary NCA Ternary NHA Ternary XYZ Ternaryfactor factor factor column gas factor

200 N2 100 N2 1 i CO2 11 CO2 1 He 1000 j H2S 10

10 Ar 10000 Ar 100 k NH3 1000

-2.8

200

mole percent of dry gas in analysis

CO2 H2S NH3 Ar N2 CH4 H2 He CO71.2 2.0 0.200 0.5100 25.6 0.28 0.13 0.00058 0.000689.5 0.7 0.001 0.0650 5.7 3.79 0.14 0.00176 -0.0002085.8 9.8 0.010 0.0430 3.9 0.19 0.22 0.00020 0.0003089.6 1.4 0.004 0.0810 5.8 2.95 0.13 0.00164 0.0005078.5 5.8 0.002 0.0710 7.5 0.47 7.64 0.00033 0.0005075.3 16.5 0.020 0.0950 7.9 0.03 0.20 0.00012 0.0005063.0 26.8 0.085 0.1100 8.8 0.08 1.19 0.00062 -0.0002073.6 21.9 0.046 0.0120 1.1 0.34 2.87 0.00202 0.0047074.8 17.4 0.002 0.0410 2.6 0.71 4.45 0.00310 0.0011080.6 17.4 0.009 0.0060 0.3 0.32 1.40 0.00069 0.0028089.0 0.1 0.001 0.1400 8.9 1.39 0.01 0.00320 -0.0001012.7 -0.1 0.000 1.9000 80.4 4.70 0.00 0.01240 -0.0010070.4 18.2 0.076 0.1000 10.2 0.15 0.90 0.00043 -0.0002060.7 20.1 0.042 0.2700 18.4 0.11 0.29 0.00065 -0.0004071.9 8.6 -0.001 0.1900 14.0 0.72 4.68 0.00290 -0.0009086.1 1.5 0.001 0.1200 8.1 2.45 1.78 0.00243 -0.0002090.6 4.2 0.001 0.1000 4.4 0.27 0.55 0.00094 -0.0002083.1 4.4 0.003 0.1800 10.4 1.25 0.65 0.00278 0.0004085.1 4.2 0.020 0.1400 9.1 1.20 0.22 0.00212 0.0000089.2 5.6 0.130 0.0600 3.8 0.85 0.32 0.00076 0.0011081.2 15.6 0.086 0.0000 0.6 0.26 2.17 0.00000 0.00000

mole percent of dry gas in analysisCO2 H2S NH3 Ar N2 CH4 H2 He CO89.92 2.25 0.45 0.09 3.60 2.25 1.35 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Enter gas analysis as percentages of gases in decimals (e.g. 95.6% = 95.6). Include reported % air to calculate the percentage of N2 and Ar from air contamination. Include %O2 if reported, and % air, % N2 and % Ar will be calculated. Enter numbers less than detection as negative numbers. Data will be plotted at the detection limit.

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

millimoles gas per 100 moles H2OCO2 H2S NH3 Ar N2 CH4 H2 He CO999 25 5 1 40 25 15 0.001 0.01

CAR-HAR COCO-CHCORH RH-2.8 -2.8

CCH Ternary

CH4mole percent of dry gas in analysis air corrected gas/steam molar ratios

%air contam air N2 air Ar-0.030 0.000 99.95 39.46 0% 0%0.052 0.248 99.95 41.77 3% 4%-0.003 0.000 99.97 42.23 0% 0%-0.007 0.000 99.97 42.03 0% 0%-0.010 0.000 99.99 38.87 0% 0%-0.007 0.000 100.05 41.00 0% 0%-0.009 0.000 100.07 39.39 0% 0%-0.004 0.000 99.88 40.26 0% 0%0.015 0.071 100.02 39.76 2% 2%-0.002 0.000 100.04 41.55 0% 0%-0.003 0.000 99.55 41.96 0% 0%0.300 1.429 100.11 29.33 1% 1%-0.007 0.000 100.03 40.11 0% 0%-0.020 0.000 99.93 38.83 0% 0%-0.050 0.000 100.14 38.77 0% 0%-0.006 0.000 100.06 41.14 0% 0%-0.001 0.000 100.12 42.62 0% 0%-0.010 0.000 100.00 41.26 0% 0%-0.001 0.000 99.98 41.68 0% 0%-0.010 0.000 99.97 42.40 0% 0%0.000 0.000 99.92 41.30 0% 0%

0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%0.000 0.00 0.00 0% 0%

0.00mole percent of dry gas in analysis 0.00

O20.090.000.000.00

Enter gas analysis as percentages of gases in decimals (e.g. 95.6% = 95.6). Include reported % air to calculate the percentage of N2 and Ar from air contamination. Include %O2 if reported, and % air, % N2 and % Ar will be calculated. Enter numbers less than detection as

O2 (if reported)

% air from O2 analysis

sum of percentages

average mol. wt.

0.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.000.00

millimoles gas per 100 moles H2OO21

Gas_Analysis_v1_Powell-2010-StanfordGW.xls Geochemical Plotting Spreadsheet

Data entry field:

1)

2)

3)

4)

5)

6)

The charts and geothermometry report in this spreadsheet are described in an accompanying article by T Powell & W Cumming delivered at the 35th Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, February 1-3, 2010. References for the calculations and charts can be found in that document

This spreadsheet accepts gas analyses and plots them in standard ternary and geothermometer grids. Data are entered or pasted into the 'Input' sheet and appear on all the graphics applicable to that data type. (Data may be cut, pasted and moved within the data entry field without changing cell addresses in the calculations)

Charts can be edited directly as EXCEL97 graphics and certain grid dimentions (e.g. multipliers on ternary diagrams and RH factors on geothermometers) which can be changed on the 'input' sheet. Fields for changing these parameters are located above the data entry field.

Rows 11 through 40 accept data (30 analyses) for the plots. The first 4 columns (Sample Name, Source, Type & Date) are not referenced by the plots and are there for user reference.

Sample Label' in column E is a text field that will determine the label for points of this data row on the plots

Columns F, G or H accept total noncondensible gas concentration either as gas/steam molar ratio (times 10 6), mole% or weight%. Only one of these values is required. Enter 1000000 (g/s ratio) or 100% for hot spring or gas seep samples where the sample is only gas (no steam). Total gas reported in other units will need to be converted to one of these units (i.e., 10*[mmole gas/100 mole H2O] = 106 g/s ratio). Total gas concentration or gas/steam ratio is needed to calculate the "Y-T" geothermometers but not for the others. If no total gas concentration is known, input 100%

Concentrations of individual gases are entered as "mole% of dry gas" and should sum to 100 in the column to the right of the input field. Individual gas concentrations reported as gas/steam ratio (in mm gas/mole H2O or mm gas/100 mole H2O) need to be converted to mole% of the total gas fraction before input. Gas analyses reported as individual gas/steam ratios should be summed to yield total gas, then divided by the gas/steam ratio of the individual gases to find mole% of each. Negative values are interpreted a "below detection" and are plotted at the detection limit.

If the gas analysis includes oxygen and an air correction to N2 and Ar concentrations has not been applied, enter the mole% oxygen and an air correction will automatically be calculated to the right and the appropriate amount of air N2 and Ar will be removed for the remainder of the analysis. If percent air contamination is given with the analysis and an air correction has been applied, enter the percent air contamination in the input field with the analysis.

Columns to the right of the input field provide quality assurance measures of the analysis. 'sum of percentages' gives the sum of the mole% values input for the analysis, and should be 100.0%. 'average mol. wt.' gives the calculated molecular weight of the gas, used to convert weight percent total gas to mole ratio. '% air N2 and '% air Ar' give the percentages of these gases introduced by air in the raw gas analysis. High percentages (>10-20%) indicate degraded accuracy in these consituents.

7)

Notes:

1)

2) Columns BR to DJ are hidden. These cells contain the geothermometer and ternary grid calculations

3)

4)

5)

6)

Version

2

Added 0.001 and 0.01 negative Y to FT Y-T charts, calculated as gas lost from equlibrated liquid in one step boiling

Added user defined ternary (Txyz)

Removed CO2-H2S-NH3 ternary. Can now be user defined in Txyz

Fixed bug in CH4 address effecting FT geothermometer calculation

Fixed bugs in air contamination calculation

Points plotted on the grids are accompanied by labels input in column E. Empty data rows (rows without input data) are plotted outside of the chart area (-99) and their data labels are blank. Labels for incomplete data will sometimes be plotted outside the chart area. These can be removed for presentation by adjusting the plot ranges of the charts. This may, however, permanently remove the labels from the data range beyond the plot range. It is recommended that graphs to be altered for presentation should be moved to a separate sheet (Menu:"Edit"/"Move or Copy Sheet"/"Create a Copy" checkbox). Alternatively, labels can be easily assigned to data using the freeware X-Y labeller add-in by AppsPro (www.appspro.com/Utilities/ChartLabeler.htm)

Columns AE to AU are hidden. These cells copy the cells in the input field based upon fixed cell addresses, so that data can be cut/pasted and moved in the input data field without changing cell addresses in the calculations.

Two additional sheets used to generate the plots are hidden but available. Ggrid has the data for the gas geothermometry grids. Tgrid has the plot data for the ternary grids. Ref has reference plot data for the ternaries, including gas solubility calculations in the CH4-CO2-H2S ternary (Tcch).

The Tchn ternary contains a CH4-CO2 geothermometer grid on the left and trend lines of gas depletion at different temperatures. Initial reservoir temperature (set in the input sheet) is the starting point for these trends. Temperatures of the trends can be changed or added from the hidden "Ref" sheet (three temperatures trends are calculated but only two are shown).

The hidden Ggrid sheet contains the Y-T data for the N2 + 3H2 = 2NH3 (NAH) gas geothermometer proposed by Giggenbach, D'Amore & Truesdell and others (see Powell, 2000), but it has not been included in this spreadsheet because if has been found to rarely work for geothermal gases, probably because its equilibration temperature is too high (400 deg C). Users of this spreadsheet are welcome to construct their own grids with this geothermometer. Acceptable grids can be constructed with NAH on the x-axis of the chart and H2S, HSH or CO2 on the y-axis. The FT-NAH grid is too flat to be useful.

Due to its low concentration in geothemal samples, many of the CO analyses plotted in the COCOCHCO geothermometer ratio grid are below detection. Plot labels are only given for analyses above detection.

2

Charts are sized to A4 paper

Added unit conversion tables below data input field to convert gas analyses in mm/100mH2O to G/S ratio and mole% dry gas. Input mm/100m data in bottom field, then copy values from upper output table to the input field of the spreadsheet. Sample name, date, etc can be input opposite mm/100m analysis data, then copied to input field above

Gas_Analysis_v1_Powell-2010-StanfordGW.xls Geochemical Plotting Spreadsheet

Data entry field:

The charts and geothermometry report in this spreadsheet are described in an accompanying article by T Powell & W Cumming delivered at the 35th Workshop on Geothermal Reservoir Engineering, Stanford University, Stanford, California, February 1-3, 2010. References for the calculations and charts can be found in that document

This spreadsheet accepts gas analyses and plots them in standard ternary and geothermometer grids. Data are entered or pasted into the 'Input' sheet and appear on all the graphics applicable to that data type. (Data may be cut, pasted and moved

Charts can be edited directly as EXCEL97 graphics and certain grid dimentions (e.g. multipliers on ternary diagrams and RH factors on geothermometers) which can be changed on the 'input' sheet. Fields for changing these parameters are located

Rows 11 through 40 accept data (30 analyses) for the plots. The first 4 columns (Sample Name, Source, Type & Date)

' in column E is a text field that will determine the label for points of this data row on the plots

Columns F, G or H accept total noncondensible gas concentration either as gas/steam molar ratio (times 10 6), mole% or weight%. Only one of these values is required. Enter 1000000 (g/s ratio) or 100% for hot spring or gas seep samples where the sample is only gas (no steam). Total gas reported in other units will need to be converted to one of these units

g/s ratio). Total gas concentration or gas/steam ratio is needed to calculate the "Y-T" geothermometers but not for the others. If no total gas concentration is known, input 100%

Concentrations of individual gases are entered as "mole% of dry gas" and should sum to 100 in the column to the right of the input field. Individual gas concentrations reported as gas/steam ratio (in mm gas/mole H2O or mm gas/100 mole H2O) need to be converted to mole% of the total gas fraction before input. Gas analyses reported as individual gas/steam ratios should be summed to yield total gas, then divided by the gas/steam ratio of the individual gases to find mole% of each. Negative values are interpreted a "below detection" and are plotted at the detection limit.

If the gas analysis includes oxygen and an air correction to N2 and Ar concentrations has not been applied, enter the mole% oxygen and an air correction will automatically be calculated to the right and the appropriate amount of air N2 and Ar will be removed for the remainder of the analysis. If percent air contamination is given with the analysis and an air correction has been applied, enter the percent air contamination in the input field with the analysis.

Columns to the right of the input field provide quality assurance measures of the analysis. 'sum of percentages' gives the average mol. wt.' gives the calculated molecular % air N2 and '% air Ar' give the percentages of

these gases introduced by air in the raw gas analysis. High percentages (>10-20%) indicate degraded accuracy in these

Columns BR to DJ are hidden. These cells contain the geothermometer and ternary grid calculations

Added 0.001 and 0.01 negative Y to FT Y-T charts, calculated as gas lost from equlibrated liquid in one step boiling

Added user defined ternary (Txyz)

Removed CO2-H2S-NH3 ternary. Can now be user defined in Txyz

Fixed bug in CH4 address effecting FT geothermometer calculation

Fixed bugs in air contamination calculation

Points plotted on the grids are accompanied by labels input in column E. Empty data rows (rows without input data) are plotted outside of the chart area (-99) and their data labels are blank. Labels for incomplete data will sometimes be plotted outside the chart area. These can be removed for presentation by adjusting the plot ranges of the charts. This may, however, permanently remove the labels from the data range beyond the plot range. It is recommended that graphs to be altered for presentation should be moved to a separate sheet (Menu:"Edit"/"Move or Copy Sheet"/"Create a Copy" checkbox). Alternatively, labels can be easily assigned to data using the freeware X-Y labeller add-in by AppsPro

Columns AE to AU are hidden. These cells copy the cells in the input field based upon fixed cell addresses, so that data can be cut/pasted and moved in the input data field without changing cell addresses in the calculations.

Ggrid has the data for the gas geothermometry has reference plot data for the ternaries, including gas solubility

The Tchn ternary contains a CH4-CO2 geothermometer grid on the left and trend lines of gas depletion at different temperatures. Initial reservoir temperature (set in the input sheet) is the starting point for these trends. Temperatures of the trends can be changed or added from the hidden "Ref" sheet (three temperatures trends are calculated but only two

The hidden Ggrid sheet contains the Y-T data for the N2 + 3H2 = 2NH3 (NAH) gas geothermometer proposed by Giggenbach, D'Amore & Truesdell and others (see Powell, 2000), but it has not been included in this spreadsheet because if has been found to rarely work for geothermal gases, probably because its equilibration temperature is too high (400 deg C). Users of this spreadsheet are welcome to construct their own grids with this geothermometer. Acceptable grids can be constructed with NAH on the x-axis of the chart and H2S, HSH or CO2 on the y-axis. The FT-NAH grid is too flat to be

Due to its low concentration in geothemal samples, many of the CO analyses plotted in the COCOCHCO geothermometer ratio grid are below detection. Plot labels are only given for analyses above detection.

Charts are sized to A4 paper

Added unit conversion tables below data input field to convert gas analyses in mm/100mH2O to G/S ratio and mole% dry gas. Input mm/100m data in bottom field, then copy values from upper output table to the input field of the spreadsheet. Sample name, date, etc can be input opposite mm/100m analysis data, then copied to input field above

Documents

Gas Analysis v2 Powell-2010-StanfordGW