Publication Date:
2020-02-12
Description:
After the Mw=9.3 Sumatra earthquake of December 26, 2004, which generated a tsunami that affected the entire Indian Ocean region and caused approximately 230,000 fatalities, the German government funded the German Indian Ocean Tsunami Early Warning System (GITEWS) Project. The GEOFON group of GFZ Potsdam was nominated to develop and implement the seismological component of the GITEWS system. This poster presentation describes the concept of the GITEWS Earthquake Monitoring System (EMS) and reports on its present status and progress of implementation. The major challenge for an EMS within a tsunami warning system is to determine earthquake source parameters in terms of location, size and possibly rupture propagation as quickly as possible, in order to allow counter measures before a potential tsunami may hit coastal areas. Tsunamigenic earthquakes usually occur along subduction zones, which are often close to coastal lines. In the Indian Ocean this is particularly true for the Sunda Trench off the shore of Indonesia and the Macran subduction zone off the shore of Iran. For an Indian Ocean monitoring system where short warning times are a requirement, a dense real-time network of seismic stations in Indonesia is therefore essential. It must be supplemented by a substantial number of stations in other countries surrounding the Indian Ocean. International cooperation and real-time data exchange across political boundaries are essential for successful tsunami warning in the Indian Ocean region. Within the GITEWS project, up to 40 new broadband and strong motion stations are being installed in the Indian Ocean region until 2010. Up to 22 new stations are set up in Indonesia and another 18 stations distributed over Sri Lanka, Maldives, Yemen, Kenya, Tanzania, Madagascar and Israel. Real-time communication is provided by private VSAT communication systems. Another challenging task within the GITEWS project is the design and implementation of efficient and fast acquisition and processing software. Based on an innovative software architecture and code, the SeisComP 3 software package has evolved from the widely used SeisComP 1 and 2 packages developed earlier by GEOFON. It combines real-time data acquisition and quality control with automatic procedures to determine location, depth, magnitudes and other source parameters. Sophisticated alert and visualization tools provide a variety of front ends. The basic parameter calculation is done fully automatic by the software. Acoustic and optical alert tools are implemented to guarantee the attention of the seismic experts in the warning center. Operators can intervene and correct automatic results to accelerate the automatic processing and to improve location accuracy. Since May 2007, SeisComP 3 is being used as the primary processing software at the Indonesian Warning Center BMG for tsunami warning purposes. The current version of the software implements a newly-developed rapid and robust regional magnitude calculation. Since it installation in Indonesia in early May 2007, SeisComP 3 has provided realistic magnitude estimates allowing assessment of an earthquake's tsunami potential and possibly warning by BMG in less than 5 minutes. The SeisComP 3 earthquake monitoring system at BMG is already connected to similar systems in Germany, the Maldives and the Republic of Yemen, for exchange of seismic waveforms and earthquake parameters in real-time. Other countries in the Indian Ocean region will follow as soon as data from their seismic stations become available. There is also interconnection between the GITEWS and the Northeastern Atlantic and Mediterranean Tsunami Warning System (NEAMTWS).
Keywords:
550 - Earth sciences
Type:
info:eu-repo/semantics/conferenceObject
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