ESARSWG: Background and Current status

Atalay Ayele AfricaArray 2nd Workshop

Palmanova, Italy

February 26-27, 2005

CONTENT

1. History

2. Current status with respect to its recent past

3. Current activities

4. Problems

5. Plans in the years ahead

6. Ethiopian case?

•Seismicity after Sieberg and Krenkel

•Rare or unknown

•Moderately frequent not violent

•Frequent occasionally destructive

•World-shaking shocks

WWSSN era since 1960s

PLUS

GDSN

HLW, AAE,

BUL, LWI?

KLMBO, LSZ FURI, ATD,

LBTB, BGCA

etc

There are a lot of events passing unnoticed at local scale b/se of poor station distribution and technology

ESARSWG formed • The first activity of ESARSWG started in 1993 in

Dar es Selam• Participating countries were: Eritrea, Ethiopia,

Kenya, Uganda, Tanzania, Zambia, Malawi, Zimbabwe

• Funded mainly by IPPS (International Program in the Physical Sciences) of UU

• Prof. Lennart.Hasselgren played a major role • University of Bergen through Prof. Jens Havskov

in training and data analysis using SEISAN

Seismic Stations in the region at the beginning

Data analysis• Mainly to produce bulletin

• At the beginning it was clumsy and costly b/se people have to carry seismograms to the analysis center

• Then we started to bring phase readings of each country on a floppy

• At the present we exchange data by e-mail and only one country processes the data and prepares the bulletin on a rotation basis

Training

• Many PhD and Msc students have been trained in Bergen and Uppsala

• That is a great capacity building in seismology in Africa

• Many technicians have been trained also at regional centers or in Norway and Sweden

Current status of seismic stations No. Country STAtn Type of instrument

Seism Comp Record Clock Period P.status

1 Eritrea ASME S-13 1SZ A/Lenarz Radio 1986- Operat.

SHBE Geophon 3SZ GeoSIG GPS 2003 Operat

GELE Geophon 3SZ GeoSIG GPS 2003 Test

ABSE L4C 1SZ D/Nanom GPS 1998- Operat.

    2

    Ethiopia

AAE Beinoff 3SZNE A/WWSSN Radio 1959- Operat.

FURI CMG-3T 3BBZNE Quantera GPS 1997- Operat

DESE Le-3d/5 3SZNE Ref.DAS GPS 1989- Operat.

WNDE Le-3d/5 3SZNE Ref.DAS GPS 1985- Operat.

ALME Le-3d/5 3SZNE Ref.DAS GPS 1986- Operat.

  3

  Uganda

ENT L4CCMG-40TL4-3D

1SZ3BZNE3SZNE

A/MEQ800D/SEISLOGD/ORION

GPSGPSGPS

1990- 1995-

Operat.DownOperat.MBAR KS-54000

CMT-3T3BZNE3SZNE

D/MK-71SP-D 

GPSGPS

1995- Operat.Operat.

KIL L4CL4-3D

1SZ3SZNE

A/MEQ-800D/ORION

GPSGPS

1990- Operat.Operat.

HOI L4CL4-3D

1SZ3SZNE

A/MEQ-800D/ORION

GPSGPS

1991 Operat.Operat.

 4

 Kenya

MAG Le-3d/5 3SZNE D/Zip drive GPS 1994- Down

KMBO IRIS 3BZNE D/IRIS GPS 1995- Operat.

MER Le-3d/5 3SZNE D/MARS88 GPS 1997- Down

LAN Le-3d/5 3SZNE D/MARS88 GPS 1997- Operat.

NAI Le-3d/5 3SZNE D/SEISLOG GPS 1995- Operat.

 5

 Tanzania

MORO L4-C 3SZNE D/ORION GPS   Operat.

MBA L4-C 3SZNE D/ORION GPS Operat.

ARTT L4-C 3BZNE D/ORION GPS 1991- Operat.

DOT L4-C 3SZNE D/ORION GPS 1990- Operat.

No CNTRY STN TYPE OF INSTRUMENT

Seism Comp Record Clock Period Present status

 6

 Malawi

CLK S-13 3SZNE A/EARSS. Radio 1962- Operational

ZOM L4-C 1SZ A/TELED Radio 1989- Down

MAL L4-C 1SZ EARSSIG   1989- Operational

MAZM

L4-C 1SZ EARSSIG   1989- Operating

LILM

L4-C 1SZ EARSSIG   1989- Operational

   7

   Zambia

LSZ Strakes 3C,VBBZNE

D/IRIS GPS 1994- Operational

             

KMZ Lennartz 3C, SPZNE

D/Reftek GPS 1998-date Down

MZZ Lennartz 3C, SPZNE

D/Reftek GPS 1998-date Down

IKZ Lennartz 3C, SPZNE

D/Reftek GPS 1998-date Down

PTZ Lennartz 3C, SPZNE

D/Reftek GPS 1998-date Down

   8

   Zimbabwe

BUL BenioffBenioff

3SZNE3LZNE

A/WWSSNA/WWSSN

RadioRadio

1957-19961957-1996

DownDown

BUL S-13 3SZNE A/ Radio 1983-1996 Down

MTD S-13 1SZ A/ Radio 1983-1995 Down

CIR S-13 1SZ A/ Radio 1983-1995 Down

KRI S-13 1Sz A/ Radio 1083-1995 Down

Current activities• Bulletin preparation is going on

• A workshop was held in Bulawayo, Zimbabwe from Feb.7 – Feb. 11, 2005

• The objective was to train seismogram analysts– The content of the training was more or less on:

• Intro. to seismic wave propagation

• Intro. to seismology and plate tectonics

• Digital filtering

• Phase picking and event locations (manually & with comp.)

• Magnitude estimates

• Demonstrating software like: SEISAN, DIMAS, PITSA, SAC

Problems• Lack of funding for station operations in all

countries (at least running cost)– respective governments are not involved in funding

or even not aware of the benefit of running seismic station network

• Fragile data archiving system

• Vandalism of equipments, specially in field

• Lack of spare parts of hardware and competent expertise to maintain stations

• Brain drain

Future plans

• To make governments aware of the problem

• Training more Msc and PhD students in the region

• Do much research on seismology and improve seismic hazard map of the region

The Ethiopian case

1CMG-3T G. &

1 Le-3d/5s

are spare

1 DAS is not operating and sent

to RefTek for maintenance

ALME station installation

Frequency content of Le-3d/5s record

Melka-Sedi (near DOFEN) earthquake as picked by ALME station

(Le-3d/5s)

The December 26, 2004 earthquake in Indonesia as recorded at our station FURI

Our location for the Indonesian earthquake using only our one station

The December 26, 2004 event at WNDE (Le-3d/5s)

The December 26, 2004 event at DESE (Le-3d/20s)