Integrated geological and geophysical analysis on the study of the structure of ultramafic bodies in the Batain nappes, Asseelah beach, Sultanate of Oman

Abstract

The northeastern region of Oman presents exceptional outcrops of carbonatite and ultramafic lamprophyre along the east coast, and they intruded a sequence of marine sedimentary rocks. This study aims to study these outcrops through geological and geophysical methods to assess their dimensions and orientations beneath the recent coastal sediments. Geologically, the area is characterized by sedimentary rocks belongings to the Batain nappes. The Batain Group consists of various formations rich in alkaline volcanic rocks, including the Wahra Formation, which hosts the studied outcrops. Fieldwork revealed folded cherts and shales with fault zones and breccias containing ultramafic lamprophyre and carbonatite. Geophysical surveys utilizing radiomagnetotelluric (RMT) soundings identified the lateral extension of these rock sequences beneath sedimentary cover. Inversion of RMT data provided insights into the resistivity distribution, delineating the ultramafic lamprophyre and carbonatite body beneath the sediments. Structural analysis suggests that these rocks were involved in transpressive deformation during late Neogene tectonic events. Despite challenges posed by conductive beach sediments, the RMT method proved effective in shaping these subsurface features, contributing to understanding the geological complexities of the region.