Source Characteristics of Earthquake 24 Sep 2019 and Their Consequences

Yıl 2021, Cilt: 3 Sayı: 3, 217 - 225, 15.07.2021

Shahzada Khurram Perveiz Khalıd

Öz

Seismogenic forces have very intense behavior in and around Pakistan. Northwest Himalayan Fold and Thrust Belt Pakistan produced due to these forces. A sequence of these stresses accumulates due to the collision of two continental plates in and around the Pakistan since 35 Ma. To explore this region and their seismotectonic activity, I have studied recently happened an unexpectedly seismic event near Jhelum Fault with epicenter 73.760E 33.100N of Mw 5.6 at focal depth 10 km. Seismotectonic map, seismicity map and focal mechanism of the study area (320–350), (720–750) was drawn. Remaining source parameters such as radiated seismic energy (E), seismic moment, P and S wave arrival time, velocity of seismic wave and surface wave magnitude were also evaluated. Intensity scale of the area was also drawn. Jhelum Fault is a strike slip fault which is almost 80 km away from epicentral location but according to source geometry of focal planes, there is no evidence for this event about strike slip fault. It seems this may be happened due to plane of weakness or stresses accumulated inside the plate due to overburden pressures, compacted and cemented rock or any due to ancient fault. So, research proclaimed that it was an intra plate earthquake with normal faulting. Additionally, peak ground acceleration of this event was also determined for further enhancement in this area i-e at 10% probability for exceedance is 2.53 m/s2 for 50 years for return period is 475 years.

Anahtar Kelimeler

Syntaxial bend, Focal mechanism, Seismicity distribution, Annual rate of exceedance, Peak ground acceleration

Kaynakça

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