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AUSTRALIAN GEOMAGNETISM REPORT

M A G N E T I C O B S E R V A T O R I E S

^ ^ ' ^ c . 2-B U R E A U O F M I N E R A L R E S O U R C E S , G E O L O G Y & G E O P H Y S I C S

V O L U M E 40 No .2

F E B R U A R Y 1992

DEPARTMENT OF PRIMARY INDUSTRIES AND ENERGY

Minister for Resources:

The Hon. Alan Griffiths MP

BUREAD OF MINERAL RESOURCES, GEOLOOY AND GEOPHYSICS

EXECUTIVE DIRECTOR:

R.W.R. Rutland AO, FTS

This report was prepared by: Geotnagnetism Section

Geophysical Observatories t Mapping Program Minerals & Environment Group

CHIEF OF DIVISION : D. Denham AM

For further Information write to:

GEOMAGNETISM SECTION BUREAU OF MINERAL RESOURCES G.P.O. Box 378 CANBERRA, A.C.T., 2601 AUSTRALIA.

BMR GEOLOGY AND G E O P H Y S I C S A U S T R A L I A

Published for the B.M.R.G. & G. by the Australian Government Publishing Service

ISSN 1035-15X5

Commonwealth of Australia 1992

COMTEMTB

Page

Contributing Observatories & Instrumentation ... 4

K-Indices 5

Principal Magnetic Storms 9

Preliminary Monthly Mean Values 10

International Quiet & Disturbed Days 10

Sudden Storm Commencements and Solar Flare Effects 11

The observers at Casey, Davis and M^cquarie Island are officers of the Antarctic Division, of the Department of the Arts, Sport, the Environment & Territories. Their contributions are gratefully acknowledged. These observers and the Bureau of Mineral Resources' (BMR) geophysicist at Mawson are members of the Australian National Antarctic Research Expedition (ANARE).

Data from the Port Moresby Geophysical Observatory are contributed by the Geological Survey of Papua New Guinea.

The terminology used in this report is that accepted by the International Association of Geomagnetism and Aeronomy (lAGA). The unit of field intensity is the nanoTesla (nT). All times are in Universal Time (UT).

CONTRIBUTING OBSERVATORIES

OBSERVATORY OBSERVER IN CHARQE

GEOORXPHIC LAT. LONG.

GEOHAGNETIC lAT. LONG.

PORT MORESBY I.D.Ripper 9- 25'S 147- 09 E -18.1* 219. .8 CHARTERS TOWERS J.M.Millican 20* OS'S 146' 15 E -28.7° 220. 3 LEARMONTH M.W.McMullan 22' 1 3 S 114* 06'E -33.2- 185. 5 GNANGARA P.J.Gregson 31* 4 7 S 115- 57 E -42.7- 188. 0 CANBERRA P.A.Hopgood 35- 19 S 149* 2 2 E -43.3' 226. 6 MACQUARIE IS. R. Jones 54* 30'S 158* 57 E -60.4' 244. ,7 MAWSON J.L.Jamieson 67- 36'S 62- 53 E -73.2- 106. 3 DAVIS D. Neudegg 68- 35'S 77* 58 E -76.8- 124. 0 CASEY N. Mifsud 66- 17 S 110- 3 2 E -77.3* 182. ,7

* Geomagnetic co-ordinates based ̂ on the 1980 DGRF Geomagnetic North pole position of 78.8'N, 70.9'W

MAGNETOGRAPHS

CODE MODEL <TYPE/RES.1 ELEMENT/SCALE-VALOE

PORT MORESBY CHARTERS TOWERS LEARMONTH GNANGARA CANBERRA MACQUARIE IS. MAWSON

PMG CTA LRM GNA CNB MCQ MAW

La Cour EDA/Elsec EDA/Elsec Elsec Elsec PEM PEN

(A) (D/1) (D/1) (D/.l) (D/.l) (D/.l) (D/.l)

H/3 X X D D X X

D/5 Y Y I I Y Y

Z/4 Z Z F F Z Z

A = analogue, 20nun/hr, scale values in nT/mm D/1 ~ digital, 1 minute readings, 1 nT resolution D/.l = digital, 1 minute readings, 0.1 nT resolution PEM - BMR Photo-electronic magnetograph

Absolute data are based on observations made with QHM's, BMZ's, fluxgate-theodolites, declinometers, proton vector magnetometers and proton precession magnetometers.

Errors in preliminary values obtained from magnetograms are not likely to exceed 5 nT or 0.5 minutes of arc.

PORT MORESBY

MAGNETIC K-INDICEe - FBBRO&BY 1992

Range for lower limit of K=9 is 300nT

D&Y K-IKDZCBS K - s m

01 2 2 3 3 4 5 4 5 28 02 4 4 4 5 5 5 4 6 37 03 6 6 5 6 5 5 5 5 43 04 4 5 4 3 3 3 5 5 32 05 4 2 2 2 2 1 1 1 15

06 1 2 0 1 2 2 2 2 12 07 3 2 4 4 4 3 2 2 24 08 4 4 5 3 6 7 4 5 38 09 6 6 6 6 6 5 4 4 43 10 4 5 3 3 5 5 3 3 31

11 3 3 2 2 2 2 2 2 18 12 3 3 2 2 3 2 1 2 18 13 3 2 3 4 1 1 1 2 17 14 1 2 3 3 2 3 1 3 18 15 1 2 1 1 2 1 1 1 10 16 1 1 1 1 1 0 1 1 07 17 3 3 4 5 5 3 3 3 29 18 3 3 2 3 2 3 2 3 21 19 3 3 3 3 3 2 2 2 21 20 5 6 5 6 5 5 5 5 42 21 4 5 7 6 6 3 3 3 37 22 3 3 4 4 2 2 2 2 22 23 3 2 2 1 1 2 2 3 16 24 4 3 3 4 4 4 5 4 31 25 - - - 5 5 3 4 3 —

26 3 3 3 3 4 5 5 5 31 27 6 5 6 7 5 5 4 3 41 28 3 2 2 2 2 0 1 2 14 29 3 1 2 5 5 5 4 3 28

Mean of K-Swa is 25.8

Frequency of K-lndiees

K S O 1 2 3 4 5 6 7 8 9 -f : 3 28 51 56 32 40 16 3 0 0 3

DAY K-IMDICBS S-SOM

01 2 2 4 3 5 4 4 6 30 02 5 3 4 5 5 3 6 6 37 03 6 6 5 6 6 5 5 6 45 04 3 3 4 3 4 3 6 6 32 05 4 1 1 3 2 1 1 2 15

06 2 1 2 2 3 2 1 2 15 07 2 2 3 5 4 3 2 2 23 08 3 3 4 3 6 6 3 6 34 09 6 5 7 6 7 6 5 4 46 10 3 4 2 2 4 4 3 2 24

11 2 1 1 1 2 2 1 2 12 12 3 2 1 1 4 3 0 2 16 13 3 1 2 2 1 0 0 1 10 14 1 0 2 2 1 3 1 2 12 15 0 0 1 0 1 0 0 1 03

16 1 0 1 0 0 1 1 1 05 17 2 1 3 4 5 2 1 2 20 18 3 3 2 2 3 3 2 3 21 19 2 2 2 2 2 3 3 3 19 20 6 4 4 5 6 5 6 4 40 21 4 4 7 7 5 2 2 2 33 22 4 3 4 3 3 3 4 3 27 23 3 2 1 2 2 2 3 2 17 24 2 2 3 3 3 4 4 6 27 25 6 5 5 5 4 4 4 4 37

26 3 3 3 3 4 6 6 5 33 27 6 4 6 6 4 5 5 3 39 28 3 2 2 3 2 2 2 3 19 29 3 2 2 4 5 6 6 3 31

OMANOARA

K-IMDICBS S-SOM

2 4 3 5 4 4 6 30 3 4 5 5 3 6 6 37 6 5 6 6 5 5 6 45 3 4 3 4 3 6 6 32 1 1 3 2 1 1 2 15

1 2 2 3 2 1 2 15 2 3 5 4 3 2 2 23 3 4 3 6 6 3 6 34

09 6 5 7 6 7 6 5 4 46 10 3 4 2 2 4 4 3 2 24

11 2 1 1 1 2 2 1 2 12 12 3 2 1 1 4 3 0 2 16 13 3 1 2 2 1 0 0 1 10 14 1 0 2 2 1 3 1 2 12 15 0 0 1 0 1 0 0 1 03

16 1 0 1 0 0 1 1 1 05 17 2 1 3 4 5 2 1 2 20 18 3 3 2 2 3 3 2 3 21 19 2 2 2 2 2 3 3 3 19 20 6 4 4 5 6 5 6 4 40 21 4 4 7 7 5 2 2 2 33 22 4 3 4 3 3 3 4 3 27 23 3 2 1 2 2 2 3 2 17 24 2 2 3 3 3 4 4 6 27 25 6 5 5 5 4 4 4 4 37

26 3 3 3 3 4 6 6 5 33 27 6 4 6 6 4 5 5 3 39 28 3 2 2 3 2 2 2 3 19 29 3 2 2 4 5 6 6 3 31

Maan of K - S m la 24.9

fraqueuoy of S-Indloas

K l 0 1 2 3 4 5 6 7 8 9 -f S 12 29 55 50 33 21 28 4 0 O O

CANBERRA

MAGNETIC K-IHDICES - 7EBRDA»Y 1992

Range for lower Ximit of K=9 is 450nT

DAY K--INDICES S-8DM

01 1 2 3 2 4 4 4 5 25 02 3 3 3 5 4 3 5 5 31 03 5 6 6 6 4 5 5 5 42 04 2 4 4 2 2 2 4 5 25 05 2 1 2 2 2 0 0 1 10

06 1 2 2 1 3 2 1 2 14 07 1 2 3 5 4 3 1 2 21 08 2 3 5 3 6 7 3 5 34 09 5 6 6 6 6 5 4 2 40 10 2 5 1 2 4 5 3 2 24

11 1 1 2 2 2 2 1 2 13 12 2 3 2 2 3 2 0 2 16 13 2 1 4 3 1 0 0 1 12 14 1 1 3 2 2 3 1 3 16 15 0 1 1 1 2 0 0 1 06

16 0 1 1 0 0 0 1 1 04 17 1 3 4 5 4 3 2 3 25 18 2 3 2 2 2 3 2 2 18 19 2 2 3 3 2 2 2 2 18 20 6 5 5 5 5 5 6 4 41

21 4 6 7 7 5 2 3 2 36 22 3 3 5 3 3 3 2 3 25 23 3 2 2 0 2 2 2 3 16 24 1 2 4 3 3 3 4 6 26 25 5 3 5 5 3 4 4 3 32

26 2 2 3 2 3 5 6 5 28 27 5 4 6 6 4 4 4 3 36 28 2 1 2 2 1 0 1 2 11 29 2 2 2 4 4 6 5 4 29

Msan of K-Sua i s 23.2

Frequency of K-iadicas

K ! 0 1 2 3 4 5 6 7 8 9 -f S 14 3 1 67 43 27 3 1 16 3 0 0 0

MAW80M MAGNETIC K-INDZCES - FEBRUARY 1.992

Range for lower limit of K»9 is ISOOnT

DAY K' "INDICES K-SUM

01 4 7 6 4 5 5 5 4 40 02 6 7 7 4 5 4 5 7 45 03 5 8 7 6 5 4 4 7 46 04 4 6 5 3 4 3 5 5 35 05 4 4 4 4 4 2 2 2 26

06 3 3 3 3 4 4 2 4 26 07 3 5 4 5 4 4 3 3 31 08 5 5 6 6 7 7 6 4 46 09 6 7 7 6 7 6 6 5 50 10 5 6 6 4 5 5 3 3 37

11 4 3 3 3 4 2 3 3 25 12 3 5 5 4 5 4 1 4 31 13 5 6 6 4 2 1 1 3 28 14 4 3 3 3 4 3 4 4 28 15 3 3 2 2 2 1 2 1 16

16 2 4 2 2 1 2 1 4 18 17 3 4 4 5 5 2 3 3 29 18 6 5 4 3 4 3 2 4 31 19 4 4 5 4 3 4 4 5 33 20 6 5 5 6 5 7 7 6 47

21 7 7 7 8 5 3 2 3 42 22 6 7 6 4 3 4 3 6 39 23 5 5 6 3 3 3 5 6 36 24 4 5 5 4 4 5 4 6 37 25 7 7 7 5 4 5 4 4 43 26 4 4 6 5 4 7 6 6 42 27 6 6 5 7 5 6 7 3 45 28 3 3 3 3 3 2 3 4 24 29 4 5 3 5 6 6 5 4 38

Hsaa of K-8ua is 35.0

Frequency of K-Indloes

K S 0 1 2 3 4 5 6 7 8 9 -f S 0 7 1 8 4 5 5 9 4 5 3 3 2 3 2 0 0

PRINCIPAL MAGNETIC STORMS - FEBRDARY 1992

Comnencement SSC-amplitude Max. 3hr K-in<Sex Ranges DT End UBSSRVATORX

Day Hr Mln Type D C ) H(nT> 2(nT) Day (3hr-perioa) K D C ) H(nT) z(nT) Day Hr

Port Moresby 01 06 08 ssc +0.8 + 17 +19 01(6,8) 5 9 140 60 02 10 02 11 53 ssc +0.5 +66 +58 02(8) ,-03(1,2,4) 6 15 190 90 05 03 08 14 27 ssc +0.9 +73 +66 08(5) 7 14 300 160 10 18 17 08 05 ssc +0.2 +21 +19 17(4,5) 5 9 90 90 18 06 20 01 08 ssc* + + 21(3) 7 14 400 190 22 12 26 16 57 ssc* +1.7* +47 +49 27(4) 7 11 190 130 28 04 29 09 20 ssc +0.4 +25 +22 29(4,5,6) 5 8 120 60 29 23

Gnangara 02 11 53 ssc -3.1 +81 -24 02(7,8); 03(1,2,4,5,8) 6 31 260 150 04 00

08 14 26 ssc -4.4 +82 -30 09(3,5) 7 48 250 300 10 06 20 01 08 ssc* +10.0* -14* +38* 21(3,4) 7 41 270 280 21 15 26 16 57 ssc* -10.0* +67 -52 26(6,7);

27(1,3,4) 6 37 220 170 28 01 Canberra 02 11 54 ssc +1.2 +88 +15 03(2,3,4) 6 29.3 242 134 04 09

08 14 28 ssc +1.3 +115 +12 08(6) 7 30.4 285 132 09 21 20 01 08 ssc -3.6 +14 +12 21(3,4) 7 38.0 272 185 21 15 24 07 03 ssc* +0.7 + 32* +3* 24(8) 6 22.4 228 75 26 00 26 16 58 ssc* +9.1* +48 -12* 26(7) ,-27(3,4) 6 22.9 203 85 28 00 29 09 21 ssc +0.7 +36 +6 29(6) 6 21.6 130 59 01 00

PRELIMINARY MONTHLY MEAM VALUES

OBSERVATORY H D z P nT deg min nT nT

PORT MORESBY 35908 06- 35. .6 ' E -23681 43014 CHARTERS TOWERS 31731 07" 47, ,3 ' E -38234 49686 LEARMONTH 29531 00° 25. ,4 ' W -44419 53340 GNANGARA 23162 03' 00. ,8 • W -53790 58565 CANBERRA 23638 12' 31. .9 • E -53636 58614 MACQUARIE IS. 12563 29 50. ,7 ' E -63457 64689 MAWSON 18512 6i' 34, .3 ' W -45910 49502 DAVIS 16664 78- 08. .4 ' W -51896 54506 CASEY 9608 92- 21, ,9' W -63872 64590

The values are derived from magnetograms over the Quietest 5 International Days, except at Mawson, Davis and Casey, where the locally quietest days are used.

INTERNATIONAL QUIET AMD DISTORBED DAYS

Quietest days (1-• 5): 16 15 05 11 06 Quietest days (6-•10): 28 14 13 12 19 Most Disturbed days : 03 09 20 21 27

10

SUDDEN STORM COMMENCEMENTS (SSC): FEBRUARY 1992 Type Sense and Amplitude

Observatory Day and U.T. of chief Movement Quality H(nT) D(nT) 2(nT)

PORT MORESBY

GNANGARA

CANBERRA

01 SSC B 0608 + 17 + 8 + 19 02 SSC A 1153 + 66 +5 + 58 08 SSC A 1427 +73 + 9 +66 17 SSC B 0805 +21 +2 + 19 20 ssc^A 0108 + + 24 SSC B 0702 + 14 + 5 + 15 26 SSC«A 1657 +47 + 18 +49 29 SSC B 0920 +25 +5 + 22 02 SSC A 1153 +81 -21 -24 08 SSC A 1426 +82 -30 -30 20 ssc*B 0108 -14* +67* + 38* 26 ssc*A 1657 +67 -67* -52 29 SSC B 0920 +36 -21 -21 01 ssc*B 0609 + 30* +3 + 3 02 SSC A 1154 + 88 +8 + 15 08 SSC A 1428 + 115 +9 + 12 17 ssc*B 0806 + 35* + 3 +2 20 SSC B 0108 + 14 -25 + 12 24 ssc*B 0703 + 32* +5 +3* 26 ssc*A 1658 +48 + 63* -12* 29 SSC B 0921 + 36 + 5 +6

SOLAR FLARE EFFECTS (•£•): FEBRUARY 1992 U.T. of s£a Con- Sense 6 Amplitude

fir-Day Began Max. Ended med. H(nT) D(nT) 2(nT)

Observatory

PORT MORESBY

GNANGARA

CANBERRA

Nil sfe's reported

Nil sfe's reported

Nil sfe's reported

11

A U S T R A L I A N G E O M A G N E T I S M R E P O R T V O L U M E 40 N o . 2 F E B R U A R Y 1992