Earthquakes occur on faults and create new faults. They also occur on normal,
reverse and strike-slip faults. The aim of this work is to suggest a new unified
classification of Shallow depth earthquakes based on the faulting styles, and to
characterize each class. The characterization criteria include the maximum
magnitude, focal depth, b-constant value, return period and relations between
magnitude, focal depth and dip of fault plane. Global Centroid Moment Tensor
(GCMT) catalog is the source of the used data. This catalog covers the period from
Jan.1976 to Dec. 2017. We selected only the shallow (depth less than 70kms) pure,
normal, strike-slip and reverse earthquakes (magnitude ≥ 5) and excluded the
oblique earthquakes. The majority of normal and strike-slip earthquakes occurred in
the upper crust, while the reverse earthquakes occurred throughout the thickness of
the crust. The main trend for the derived b-values for the three classes was: b normal
fault>bstrike-slip fault>breverse fault. The mean return period for the normal
earthquake was longer than that of the strike-slip earthquakes, while the reverse
earthquakes had the shortest period. The obtained results report the relationship
between the magnitude and focal depth of the normal earthquakes. A negative
significant correlation between the magnitude and dip class for the normal and
reverse earthquakes is reported. Negative and positive correlation relations between
the focal depth and dip class were recorded for normal and reverse earthquakes,
respectively. The suggested classification of earthquakes provides significant
information to understand seismicity, seismtectonics, and seismic hazard analysis.
عماد عبد الرحمن محمد صالح الهيتي | Emad Andulrahman Mohammed Salih Al-Heety | 4166