The 1956 Chim earthquake was a destructive multiple-shock event that occurred on March 16 in Lebanon along a strand of the Dead Sea Transform (DST) fault system.[1] The epicenter was located in the south of Lebanon in the Chouf District. Six thousand homes were destroyed and another 17,000 were damaged. The number of persons killed was 136.[2]
Tectonic setting
The DST is a 1,609 km (1,000 mi) long transform fault that runs in a mostly north–south direction from the northern end of the Red Sea along the Jordan Rift Valley to the Taurus Mountains complex in southern Turkey. The left-lateral fault zone marks the boundary of the Arabian plate and the Sinai-Levantine block and consists of multiple parallel faults.[3] As the fault moves through Lebanon and Syria the fault trace follows a restraining bend and splits into several strands that include the Serghaya, Rachaya, and Roum faults, as well as the prominent Yammouneh fault.[4]
Earthquake
The Roum fault runs for a length of 35 kilometers (22 mi) between the Hula basin the Awali river and is the westernmost strand of the fault system in that area. A paleoseismic trench investigation revealed that it may have been the source of the twin-shock event.[5]
The twin shocks were separated by less than fifteen minutes with the first event occurring at 19:32 and the second event at 19:43 hours.[2] The initial shock was estimated to measure (Mw = 5.3) and the second event was rated (Mw = 5.5).
^Nemer, Tony; Meghraoui, Mustapha (2006), "Evidence of coseismic ruptures along the Roum fault (Lebanon): a possible source for the AD 1837 earthquake", Journal of Structural Geology, 28 (8): 1483–1495, Bibcode:2006JSG....28.1483N, doi:10.1016/j.jsg.2006.03.038
