ESARSWG Background and Current status Atalay Ayele Africa

ESARSWG: Background and Current status Atalay Ayele Africa. Array 2 nd Workshop Palmanova, Italy February 26 -27, 2005

CONTENT 1. 2. 3. 4. 5. 6. History Current status with respect to its recent past Current activities Problems Plans in the years ahead Ethiopian case?

• Seismicity after Sieberg and Krenkel • Rare or unknown • Moderately frequent not violent • Frequent occasionally destructive • World-shaking shocks

WWSSN era since 1960 s PLUS GDSN HLW, AAE, BUL, LWI? KLMBO, LSZ FURI, ATD, LBTB, BGCA etc

There 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 Ph. D 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. 1 2 3 Country Eritrea Ethiopia Uganda STAtn Seism Comp Record Clock Period P. status ASME S-13 1 SZ A/Lenarz Radio 1986 - Operat. SHBE Geophon 3 SZ Geo. SIG GPS 2003 Operat GELE Geophon 3 SZ Geo. SIG GPS 2003 Test ABSE L 4 C 1 SZ D/Nanom GPS 1998 - Operat. AAE Beinoff 3 SZNE A/WWSSN Radio 1959 - Operat. FURI CMG-3 T 3 BBZNE Quantera GPS 1997 - Operat DESE Le-3 d/5 3 SZNE Ref. DAS GPS 1989 - Operat. WNDE Le-3 d/5 3 SZNE Ref. DAS GPS 1985 - Operat. ALME Le-3 d/5 3 SZNE Ref. DAS GPS 1986 - Operat. ENT L 4 C MBAR 1 SZ 3 BZNE 3 SZNE 3 BZNE A/MEQ 800 D/SEISLOG D/ORION D/MK-71 SP-D GPS GPS 1990 - CMG-40 T L 4 -3 D KS-54000 Operat. Down Operat. MAG L 4 C L 4 -3 D Le-3 d/5 3 SZNE 1 SZ 3 SZNE A/MEQ-800 D/ORION D/Zip drive GPS GPS GPS KMBO IRIS 3 BZNE D/IRIS MER Le-3 d/5 3 SZNE LAN Le-3 d/5 NAI 1994 - GPS 1995 - Operat. D/MARS 88 GPS 1997 - Down 3 SZNE D/MARS 88 GPS 1997 - Operat. Le-3 d/5 3 SZNE D/SEISLOG GPS 1995 - Operat. MORO L 4 -C 3 SZNE D/ORION GPS Operat. MBA L 4 -C 3 SZNE D/ORION GPS Operat. ARTT L 4 -C 3 BZNE D/ORION GPS 1991 - Operat. DOT L 4 -C 3 SZNE D/ORION GPS 1990 - Operat. HOI 5 Kenya Tanzania CMT-3 T 1995 - Operat. Down KIL 4 Type of instrument 19901991

No 6 7 8 CNTRY STN TYPE OF INSTRUMENT Seism Comp Record Clock Period Present status CLK S-13 3 SZNE A/EARSS. Radio 1962 - Operational ZOM L 4 -C 1 SZ A/TELED Radio 1989 - Down MAL L 4 -C 1 SZ EARSSIG 1989 - Operational MAZ M L 4 -C 1 SZ EARSSIG 1989 - Operating LIL M L 4 -C 1 SZ EARSSIG 1989 - Operational LSZ Strakes 3 C, VBB ZNE D/IRIS GPS 1994 - Operational KMZ Lennartz 3 C, SP ZNE D/Reftek GPS 1998 -date Down MZZ Lennartz 3 C, SP ZNE D/Reftek GPS 1998 -date Down IKZ Lennartz 3 C, SP ZNE D/Reftek GPS 1998 -date Down PTZ Lennartz 3 C, SP ZNE D/Reftek GPS 1998 -date Down BUL Benioff 3 SZNE 3 LZNE A/WWSSN Radio 1957 -1996 Down BUL S-13 3 SZNE A/ Radio 1983 -1996 Down MTD S-13 1 SZ A/ Radio 1983 -1995 Down CIR S-13 1 SZ A/ Radio 1983 -1995 Down KRI S-13 1 Sz A/ Radio 1083 -1995 Down Malawi Zambia Zimbabwe

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 Ph. D students in the region • Do much research on seismology and improve seismic hazard map of the region