Indonesian archipelago is located in the convergence zone of four major tectonic plates:Eurasian plate, Indian-Australian plate, Pacific plate and Philippine plate. Interaction ofthese plates affected the seismo-tectonic of the Indonesian region.

The Indian-Australian plate moving northwards relative to Eurasian plate and the Pacific plate moving westward relative to both Indian-Australian and Eurasian plate.

Moreover, as a result of the India and Australia plates converging with and subducting beneath the Sunda plate at a rate of approximately 50 to 70 mm/ybeneath the Sunda plate at a rate of approximately 50 to 70 mm/yr.

An earthquake with a magnitude of 5.7 Mw (USGS) occurred at Kabupaten Deli Serdang on January 16, 2017. The epicenter was shallow with a depth of 10 km. Global CMT cata-log revealed that mechanism of this earthquake is dextral fault where a block of fault move relatively to the right of another block. Seismic network recorded 9 aftershock occurred until 21.00pm in the Deli Serdang.

Based on Geological Map, the local tectonic shows that in southeast Berastagi near the lo-cation of the epicenter there are some local fault structure with approximately length are 34km. The historical catalogue also show the area had experienced earthquake in the previ-ous year from the depths of 10-50km.

Based on the shake map of Maipark Cat Model, the intensity of the quake was felt in Kab. Deli Serdang V-VI MMI; Kota Medan and Kota Pematang Siangtar IV MMI. The intensity was moderate to strong and indicate light/moderate shaking.

Preliminary result from Maipark Cat-model has estimated economic (number of houses) 200 billion from this event. BPBD Reported some houses were damaged but still the data collection. Until now there has been no report of casualties. We expect small part of insurance losses.

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