Shear Velocity from Seismic Ambient Noise to Determine Crustal Structure and Re-Fitting Rock Physics Modeling in Dhafriyah and Kumaite Oil Fields

Abstract

The current study aims to estimate the cortical structure of this region in Dhafriyah and Kumaite Oilfield. The cross-correlation of ambient seismic noise was applied in Anbar, Karbala, and Amarah to estimate a detailed velocity model for the sedimentary cover using data from three broadband seismic stations. Rayleigh wave dispersion curves were applied to obtain an accurate velocity model of the sedimentary cover. The results show that the crustal structure in the study area has three distinct discontinuities; the first is the discontinuity within the sedimentary cover column with a thickness around 4km (Vs 2.44km/s); the second is the basement rocks with a depth of 12km (Vs 3.17km/s), and the third is the Moho discontinuity with a depth of 46km (Vs 3.87km/s). Thus, the sedimentary thickness in the study area is around 12 km and the continental crust is around 34km. The first one, is done with using final out-puts of the velocity model of ANT (Vp, Vs, RHOB) to refitting rock physics modeling. The results show a good match with seismic cubes results may be used for prospect evaluation across different fields Dhafriyah and Kumaite, reservoir characterization, and formation evaluation.