Description of soft sediment deformational structure of the Campano-Maastrichtian Gombe formation of the Northern Benue Trough, N.E. Nigeria

Abstract

Several soft sediment deformational structures were identified during fieldwork survey carried out on exposures of Gombe Formation in the Gongola sub-basin of the Northern Benue Trough at Gombe and environs. These soft sediment deformational structures includes: simple internal cusps, which occur wide spread across a single bed or intermittently across several beds, and slump structures that are represented by complex recumbent folds and concave upwards structures. These structures are proxy to syn-depositional energy operating within the depositional environment and this current research aims to evaluate their trigger mechanism. These deformational structures are commonly hosted in the mouth-bar deltaic sequences of the Gombe Formation. The deltaic setting is usually a locus for high sediment influx and accumulation. This may have generated high quantum of depositional energy which was probably responsible for the development of the syn-depositional soft sediment depositional structures in the Gombe Formation during Campano-Maastrichtian times.