Jv. AUSTRALIA,,

BUREAU OF MINERAL RESOURCES.

GEOLOGY & GEOPHYSICS

074010 GEOPHYSICAL OBSERVATORY

\ / A T O R I E S

Vo lume 28 , N o . 4

A p r i l 1 9 8 0

DEPARTMENT OF NATIONAL DEVELOPMENT WD ENERGY

MINISTER: Senator The Hon. J . L . Ca r r i c k

SECRETARY: A, Woods

BUREAU OF MINERAL RESOURCES, GEOLOGY & GEOPHYSICS

ACTING DIRECTOR: L.W. Wi l l i ams

THIS REPORT WAS PREPARED IN THE GEOPHYSICAL KRANCH

ACTING ASSISTANT DIRECTOR: J.C. Dooley

SUPERVISING GEOPHYSICIST: P»M. McGregor

ISS^ 0433-5015

Commonwealth of Australia 1980

Printed by Canberra Publishing and Printing Company.

CONTENTS

Rage

Contr ibut ing O b s e r v a t o r i e s . . . . 2

K - l nd i c e s . . 3

P r i nc ipa l Magnetic Storms., 11

Monthly Mean Va lues , Sudden Commencements and Other Rapid Va r i a t i on s 12

The observers at Casey and Dav is are p h y s i c i s t s of the Anta rc t i c D i v i s i o n (Department of Science and the Environment) and t he i r con t r i bu t i on s are g r a t e f u l l y acknowledged: they and the BIR geophy s i c i s t s at Macquarie I s land and Mawson are members of the Au s t r a l i a n National An ta rc t i c Research Expedit ions (ANARE).

The data from the Port ^bresby geophysical observatory are contr ibuted by the Geological Survey of Papua New Guinea.

The terminology used in t h i s report is that accepted by In terna-t iona l convenct ion. The un i t s of f i e l d i n ten s i t y , nanotes ia (nT), are those of the S I system. Al l times are in Universa l Time, Should fu r ther information be requ i red, apply to :

GEOPHYSICAL OBSERVATORY SUBSECTION BUREAU OF MINERAL RESOURCES P.O. 378 CANBERRA CITY, A.C.T, 2601

CONTRIB l/r ING OBS ER VATORIES

GEOGRAPHIC OBSERVATORY OBSERVER

GEOMAGNETIC

IN CHAR(X LAT LONG LAT LONG

PORT MORESBY I .D. Ripper 9°25 ' S 147°09'E - 1 8 . 6 ° 217.9° GNANGARA P.J. Greg son 31 4 7 ' S 115°57'E - 4 3 . 3 ° 185.8 CANBERRA R.S . Smith 35°19 'S 149°22'E - 4 4 . 0 ° 224.7°

nOOLANGI R.S. Smith 37°32 'S 145°28'E - 4 6 . 7 ° 220.8° MAC(^ARIE 1 P.M. Davies 54°30>S 158°57'E - 6 1 . 1 ° 243.1° MAWSON B.A. Gaull 6 7 ° » ' S 62°53 'E - 7 3 . 1 ° 102.9° DAVIS P. Murrel1 68°35 ' S 77°58«E - 7 6 . 7 ° 119.9° CASEY K. Lew i s 66°17 'S 110°32'E - 7 7 . 8 ° 179.1°

MAGNETOGRAPHS

NOMINAL SCALE VALUES

OBSERVATORY TYPE NORMAL SENS IT IVE

D H Z D H Z

PORT MORESBY La Cour 0 .5 3 4 GNANGARA Eschenhagen 1 3 5 TOOLANGI La Cour 1 5 5 MACQUARIE 1 La Ctour 2.5 20 21 MAWSON La Cour 2 .5 21 22 1 10 10 CANBERRA El sec d i g i t a l D F 1

0. InT

Sca le values are in minutes of arc/mm (D) and nT/mm {H,Z)

H4i\GNET0METERS

Abso lute data are based on observat ions made with QHM'S BMZ ' s decl inometers and proton precess ion magnetometers. E r r o r s in prel iminary va lues are not l i k e l y to exceed 5 nT or 0.5 minutes.

*From 1 Ju l y 1979 Toolangi Observatory is on ly a v a r i a t i o n observatory .

PORT MORESBY

MAGNETIC K- INDICES - APRIL 1980

Range for lower I Im i t of K = 9 i s 500 nT

Day K - I n d i c e s K-Sum

01 02 03 04 05 06 07 08 09 10 11

12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

2 0 2 1

1

2 3 3 3 3 3 4 3 1 3 2 2 0 0 2 1

4 1 1 3 1 1

1 2 1

0 0 2 1 1 2 3 4 4 3 3 4 4 1 2 3 2 1 1 2 0 4 2 1 3 3 2 1 2 2

2 0 3 3 1 1

4 4 4 3 4 4 3 1 4 3 2 1 1 1

1

2 2 2 3 1 1 1 1 1

2 0 2 3 1 4 2 4 6 4 3 3 3 0 2 2 1 1 1 2 1 2 1 2 4 1 2 1 1 2

2 0 1 2 2 3 2 4 5 4 2 3 2 0 1 2 1 0 1 2 0 2 2 1 4 2 1 2 1 3

0 0 1 2 3 5 2 2 3 3 3 3 2 2 2 2 2 0 1

1

0 1

2 2 3 1

2 2 0 2

0 0 1 2 1 4 3 1 2 3 4 3 2 3 3 0 0 0 0 1 0

0 2 0 1 1 3 3 3 2 3 4 3 0 3 3 1 0 0 1 2 0 1 1 1 1 2 2 1 1 1

02 12 15 11 24 22 25 29 26 26 27 19 14 20 15 10 03 06 13 03 17 12 11

22 12 12 10 09 13

GNANGARA

MAGNETIC K- IND ICES - APRIL 1980

Range for lower I Itnit of K = 9 i s 450 nT

Day K - 1nd ices K-Sum

01 2 1 1 0 2 2 1 0 09 02 0 1 0 1 1 1 1 1 06 03 3 2 1 2 1 2 2 1 14 04 1 2 3 3 2 3 3 2 19 05 2 2 1 1 1 3 2 1 13 06 1 2 1 3 3 4 4 4 22 07 3 3 3 2 2 2 4 4 23 08 3 3 3 2 4 2 2 3 22 09 4 3 3 5 4 4 1 2 26 10 3 2 3 4 2 2 2 2 20 11 3 2 4 3 3 3 6 4 28 12 4 3 3 3 4 3 3 5 28 13 4 3 3 3 1 3 3 1 21 14 0 1 1 0 2 2 2 3 11 15 4 3 3 1 1 3 3 4 22 16 1 2 2 2 2 3 3 2 17 17 2 2 2 1 1 2 2 1 13 18 0 1 1 1 0 1 0 1 05 19 1 0 1 0 1 2 2 2 09 20 1 1 1 1 0 3 2 09 21 1 1 1 0 1 1 0 0 05 22 3 3 1 1 2 1 1 1 13 23 2 2 1 1 1 1 1 2 11 24 1 1 1 0 2 3 1 1 10 25 2 2 3 3 1 0 1 14 26 0 2 1 0 2 1 1 1 08 27 0 1 1 0 2 1 1 2 08 28 1 1 1 1 2 2 1 1 10 29 2 1 1 0 1 0 1 1 07 30 2 1 1 1 3 1 2 2 13

TOOLANGI

MAGNETIC K-INDICES - APRIL 1980

Range for lower 1 imit of K = 9 I s 500 nT

Day K - l nd i ce s K-Sum

01 0 0 1 0 3 1 1 0 06 02 0 0 0 0 1 0 0 1 02 03 1 2 1 2 1 2 2 1 12 04 0 2 3 3 2 3 3 1 17 05 0 1 0 0 1 2 1 1 06 06 0 2 1 4 3 4 4 3 21 07 2 2 3 1 2 2 4 3 19 08 3 4 3 3 5 2 1 3 24 09 2 4 3 5 4 3 0 1 22 10 2 3 3 4 2 1 2 2 19 11 2 3 4 4 3 3 5 4 28 12 4 3 2 3 3 3 3 4 25 13 3 3 3 3 1 3 2 1 19 14 0 - - - - - - 3 —

15 3 2 3 1 1 3 3 3 19 16 1 3 3 1 2 3 2 2 17 17 2 2 1 0 1 2 0 1 09 18 0 1 1 1 0 0 0 0 03 19 0 0 1 0 1 1 0 0 03 20 1 0 0 2 0 1 2 07 21 1 0 1 0 1 0 0 04 22 3 1 1 2 1 1 1 12 23 2 0 0 1 1 0 0 05 24 1 0 0 1 0 1 07 25 2 1 4 3 1 0 1 14 26 1 1 0 2 1 1 0 07 27 2 1 0 1 0 1 08 28 0 1 0 1 1 1 0 0 04 29 2 1 1 2 1 0 1 09 30 1 1 I 1 2 2 1 1 10

MACQUARIE ISLAND

MAGNETIC K- INDICES - APRIL 1980

Range for lower 1imit of K = 9 i s 1500 nT

Day K - 1nd ices K-Sum

01 1 1 0 0 5 3 0 0 10 02 0 0 0 0 1 0 0 1 02 03 1 2 0 0 1 1 1 0 06 04 0 1 2 2 2 2 1 0 10 05 1 1 0 0 0 3 1 0 06 06 0 2 1 1 6 6 6 4 26 07 2 2 2 1 4 2 3 3 19 08 3 3 2 5 6 2 1 1 23 09 1 4 5 6 6 4 2 1 29 10 2 6 5 7 5 1 1 1 28 11 1 2 4 6 4 6 7 4 34 12 4 5 4 5 6 5 3 4 36 13 4 3 6 5 2 2 3 1 26 14 1 1 0 1 2 4 1 2 12 15 4 4 5 1 1 4 5 2 26 16 2 5 3 3 2 3 2 0 20 17 2 4 2 0 0 1 1 1 11 18 1 1 0 2 1 0 0 0 05 19 0 1 0 2 1 0 0 0 04 20 1 1 0 0 3 0 0 0 05 21 1 1 0 1 0 0 0 0 03 22 1 1 0 0 2 2 0 0 06 23 1 2 0 0 0 0 0 0 03 24 0 1 1 1 1 2 0 0 06 25 2 2 1 5 4 0 0 0 14 26 0 1 0 0 3 1 0 0 05 27 0 1 0 1 0 1 0 0 03 28 0 1 0 1 1 1 0 0 04 29 1 1 1 0 1 0 0 0 04 30 2 1 0 1 3 1 0 1 09

01 3 4 3 5 02 5 5 4 4 03 5 6 4 4 04 3 5 5 4 05 4 4 4 4 06 4 5 4 3 07 1 3 3 2 08 4 4 4 3 09 3 3 1 1 10 2 2 1 1 11 3 3 3 4 12 4 - 3 2 13 3 3 5 5 14 4 4 3 3 15 3 3 2 3 16 4 - - -

17 - 4 5 4 18 3 4 2 2 19 3 3 3 2 20 5 4 3 2 21 3 4 3 2 22 2 2 3 2 23 4 4 4 3 24 3 2 2 2 25 3 1 2 2 26 3 4 3 3 27 5 6 3 4 28 5 6 5 4 29 6 5 5 3 30 4 4 4 5 31 4 3 2 2

MAWSON

MAGNETIC K- INDICES - JANUARY 1980

Range for lower l im i t of K = 9 i s 1500 nT

K- Ind1ces K-Sum

3 4 3 5 5 5 5 4 34 5 5 4 4 5 3 2 3 31 5 6 4 4 4 3 5 4 35 3 5 5 4 4 4 5 4 34 4 4 4 4 4 3 5 5 33 4 5 4 3 3 3 3 3 28 1 3 3 2 3 3 3 5 23 4 4 4 3 2 0 1 2 20 3 3 1 1 2 1 1 1 13

10 2 2 1 1 3 3 2 2 16 11 3 3 3 4 4 4 5 4 30 12 4 - 3 2 3 2 2 2 13 3 3 5 5 5 5 6 4 36 14 4 4 3 3 4 3 2 4 27 15 3 3 2 3 4 3 3 2 23 16 4 _ _ _ _ _ _ _ 17 - 4 5 4 4 3 2 2 18 3 4 2 2 2 2 4 4 23 19 3 3 3 2 2 2 4 3 22 20 5 4 3 2 2 3 3 4 26 21 3 4 3 2 3 3 2 1 21 22 2 2 3 2 3 2 4 4 22 23 4 4 4 3 3 2 2 2 24 24 3 2 2 2 3 3 3 3 21 25 3 1 2 2 3 2 3 4 20 26 3 4 3 3 2 3 2 5 25 27 5 6 3 4 5 4 6 5 38 28 5 6 5 4 5 6 5 4 40 29 6 5 5 3 5 6 5 6 41 30 4 4 4 5 4 3 4 3 31 31 4 3 2 2 2 2 3 4 22

MAWSON

MAGNETIC K-INDICES - FEBRUARY 1980

Range for lower 1imit of K = 9 I s 1500 nT

Day K-' 1 nd1ces K-Sum

01 4 4 3 3 2 3 6 5 30 02 4 5 4 3 3 2 1 3 25 03 3 4 2 1 2 0 1 3 16 04 3 2 4 2 2 0 0 1 14 05 2 3 2 2 3 2 2 1 17 <X> 3 4 6 6 6 7 7 2 41 07 3 3 5 2 4 3 5 8 33 08 5 6 5 5 4 5 4 5 39 09 3 4 4 4 4 5 5 4 33 10 4 4 3 I 1 1 1 1 16 11 4 4 3 1 1 1 0 0 14 12 1 2 2 2 2 1 0 3 13 13 3 2 2 1 1 0 2 2 13 14 3 4 - - - 4 4 2 —

15 4 4 3 4 2 2 6 7 32 16 6 6 7 6 5 4 5 4 43 17 1ft

3 2 3 1 2 1 - - —

lo 19 _ 6 4 2 1 0 0 7 20 4 3 3 3 2 3 1 4 23 21 4 3 3 1 1 1 1 3 17 22 2 2 2 2 2 2 1 3 16 23 2 2 3 3 3 5 5 4 27 24 3 4 4 2 3 3 0 1 20 25 2 3 2 2 2 3 4 5 23 26 5 4 3 3 3 3 5 3 29 27 2 4 4 4 4 3 4 4 29 28 4 5 3 4 4 2 5 5 32 29 5 4 2 2 3 2 3 4 25

MAWSON

MAGNETIC K-INDICES - FEBRUARY 1980

Ranqe for lower 1imit of K = 9 i s 1500 nT

Day K - 1nd i ces K-Sum

01 4 5 1 0 1 0 0 1 12 02 1 3 1 1 0 1 1 2 10 03 3 2 2 1 1 4 3 5 21 04 2 1 2 3 2 1 1 4 16 05 4 4 3 3 3 0 1 1 19 06 2 4 3 3 3 2 1 3 21 07 4 4 2 2 1 1 5 4 23 08 2 4 4 2 2 1 2 3 20 09 4 2 3 2 2 2 1 4 20 10 1 2 2 2 1 1 0 0 09 11 4 1 1 3 1 1 1 2 14 12 1 0 0 0 0 0 1 1 03 13 2 2 3 1 1 1 5 5 20 14 4 3 2 2 1 1 2 3 18 15 1 0 0 0 0 0 0 5 06 16 4 1 1 2 1 1 0 3 13 17 2 2 1 1 1 0 1 4 12 18 3 2 1 0 0 0 0 2 08 19 1 2 4 3 2 2 0 0 14 20 2 2 2 2 0 0 3 3 14 21 3 6 5 4 3 4 5 5 35 22 4 5 5 2 4 4 3 6 33 23 4 4 3 2 2 1 0 0 16 24 1 3 2 2 2 1 1 4 16 25 1 2 1 1 1 0 0 4 10 26 6 6 6 5 3 1 4 5 36 27 4 2 2 2 2 0 2 5 19 28 4 4 3 2 1 0 0 5 19 29 4 5 4 1 1 1 3 5 24 30 5 4 5 1 2 1 I 1 20 31 3 5 5 4 3 3 2 4 29

MAWSON

MAGNETIC K-INDICES - APRIL 1980

Ranqe for lower 1imit of K = 9 i s 1500 nT

Day K - Indices K-Sum

01 5 3 I 1 1 3 5 4 23 02 4 4 1 1 0 0 0 2 12 03 2 4 3 3 0 2 2 1 17 04 1 2 3 4 2 3 5 2 22 05 4 4 2 1 2 4 3 1 21 06 2 5 2 4 4 4 3 3 27 07 3 3 4 2 3 2 5 6 28 08 4 5 3 3 3 2 3 3 26 09 5 7 6 5 5 3 1 1 33 10 3 7 5 4 2 2 1 3 27 11 5 3 5 3 3 6 7 6 38 12 6 5 5 3 2 4 4 7 36 13 5 4 4 3 2 3 5 6 32 14 3 3 3 2 1 3 4 6 25 15 6 5 4 2 1 5 6 6 35 16 3 4 4 3 1 5 4 6 30 17 6 5 3 2 1 1 4 5 27 18 3 2 1 1 0 2 7 5 21 19 2 1 2 1 2 2 4 5 19 20 4 4 2 1 0 0 5 5 21 21 4 3 3 1 0 1 5 5 22 22 3 3 1 1 1 2 3 3 17 23 4 3 1 1 1 0 1 5 16 24 5 4 2 1 2 3 3 2 22 25 4 4 2 2 3 1 0 0 16 26 1 5 3 0 1 0 0 2 12 27 1 3 2 1 1 1 0 5 14 28 5 3 1 1 1 2 1 0 14 29 2 2 2 1 1 0 1 3 12 30 2 4 1 2 2 2 3 4 20

10

APRIL 1980 PRINCIPAL MAGNETIC STORMS

OBSERVATORY

COMMENCEMENT s sc AMPLITUDES MAX : 3h INDEX K RANGES UT END

OBSERVATORY

d h min TYPE D C ) H(nT) Z(nT) d (3h-PERI0D) K D C ) H(nT) Z(nT) d h

PORT MORESBY OS 10 59 s sc +0,5 +31 +26 06 (6) 5 8 110 50 08 18 08 23 31 s sc +0,3 +20 +18 09 (4) 6 10 160 80 13 20

GNANGARA m 11 00 s s c +2.4 +29 + 16 06 (6,7,8) 14 60 100 CB 18 07 C7,8) 08 (5)

09 05 08 s s c * - 2 2 * + 5 - 11 * 09 (4) 5 17 80 110 13 09

TOOLANGI 09 05 09 s s c * - 0 , 8 +31* + 3 9 (4) 5 20 100 50 10 13 11 03 9 » 0 6 9 • » 9 e 9 9 11 (7) 5 17 140 60 13 06

APRIL 1980

PRELIMINARY MONTHLY MEAN VALUES

H D Z F DBSERVATORY

nT 0 ' nT nT

PORT MORESBY 35973 06 28.OE -23634 43042 GNANGARA 23410 03 17.5W -53644 58529 CANBERRA 23812 12 08.3E -53769 58805 TOOLANGI no abso lute control MACQUARIE 1 12718 28 28.3E -63775 65031 MAWSON 18425 63 07.2W -46812 50307 DAVIS not a va i l ab l e CASEY not a v a i l a b l e

MAWSON PRELIMINARY MONTHLY MEAN VALUES

January February March

18451 18444 18435

62 58.8W 63 03.9W 63 04.8W

-46814 -46810 -46810

50319 50313 5O309

The values are derived from magnetograms for selected quiet days except at Dav is and Casey where they are derived from semi-weekly abso lute measurements.

SUDDEN COMMENCEMENTS AND OTHER RAPID VARIATIONS

OBSERVATORY TYPE AND

DAY QUALITY TIME

SENSE AMD AMPLITUDE OF CHIEF MOVEMENT

H(nT) D(nT) Z(nT)

PORT MORESBY s s c B 1059 +31 + 6 +26 08 BSC B 2331 +20 + 3 +18

GNANGARA C» SSC B 1100 +29 +16 +12 09 SSC* B 0508 + 5 - 1 6 * - 1 1 *

TOOLANGI s s c B 1100 +44 + 5 + 6 09 SSC* B 0509 +31« - 5 + 3

12

R79/271 (11) Cat. No. 80 1211 6