Scientific Quarterly Journal of Geosciences

Scientific Quarterly Journal of Geosciences

Study of crust in Izeh area (around Karoun dam) by inverting P wave travel times data recorded in the area

Document Type : Original Research Paper

Authors
Mahmoud Mirzaei 1
Mohammad Reza Gheitanchi 2
1 Arak University , Arak, Iran
2 Institute of Geophysics, Tehran University, Tehran, Iran
Abstract
Method of seismic travel time inversion for simultaneous determination of 2-D velocity is used to invert p-wave data recorded by seismograms in Izeh area. The inversion scheme used is iterative and is based on a model parameterization and a method of ray tracing. To study local seismicity around Karoun dam in Izeh area, a temporary earthquake network of seismograph stations was established that during three years had recorded about 800 earthquakes occurred around the darn. The first arrival times are used as data for inversion to determine the structure of the crust in this area. An initial five- layer model with depth and velocity as parameters have been defined using the primary data interpretation and present information in the area. The Initial model is optimized by inverting p arrival times. using a program, in a manner that time response best lit with the data. The optimized depth and velocity parameters due to inversion arc employed to show contour map of the interface depth of the layers and velocity variations at different depth in order to study the crust in the area. Observed discontinuities on the maps are related to the faults in the area which are proved by area geology map.
Keywords
Seismic travel time inversion
2D velocity structure
Crustal structure in Izeh
Seismicity of Izeh
Active Faults

Subjects

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Scientific Quarterly Journal of Geosciences
Volume 11, 43-44
Spring & Summer 2002, Vol. 11, No. 43-44
Summer 2002
Pages 46-55