Mapping of near-surface formations by refraction seismic tomography: a case study from Al-Amerat, Sultanate of Oman

Abstract

In this study, a seismic refraction survey is conducted to image the structure of the bedrock and overlying rocks in Wadi Al-Mayh from Al-Amerat, Northern Oman. The bedrock is a consolidated and impermeable metamorphic rock. The porous and unconsolidated rocks lying above the bedrock have played a key role in transporting and storing water from rainfall. Seismic data were collected from 8 seismic profiles acquired along the wadi. Tomographic inversion of the data has produced velocity models that have contributed to understand how the water accumulates, migrates, and charges the aquifer in the subsurface of the wadi. Data from the exposed rocks on surface and from a water-producing well in the area were used to calibrate the velocity models. The latter models were used to build 3-D depth map that not only helped to understand the distribution of porous and permeable zones but also has provided an interpretation for a water-producing well in the area that has run dry after decades of production.