Tectono-stratigraphic evolution of the offshore Benin Basin, SW Nigeria
type: CreativeWork
description: This thesis presents an evaluation of the tectonic and stratigraphic evolution of the offshore Benin Basin based on the analysis of 2D and 3D seismic data, in addition to exploration well data of four closely-spaced wells. To date, little has been published on this part of the African Equatorial Atlantic margin because of the lack of publicly available datasets, and this is the first academic study to be provided with 3D seismic data from this basin. The aims of the study were to establish a tectono-sequence stratigraphic framework for the basin, and to establish the timing, distribution, and nature of tectonic and gravity-driven deformation events. This tectono-stratigraphic evolution was then compared to adjacent and formerly adjacent basins to better understand their significance in relation to the opening of the Equatorial Atlantic and its post-drift history. Five megasequences have been identified which relate to key tectonic phases in the basin history, and/or major changes in its genetic stratigraphic behaviour. These sequences have been subdivided into seismic sequences. The megasequences are MS1- pre-rift (Precambrian - Barremian); MS2 - syn-rift (Barremian - late Aptian); MS3 - Cretaceous post-rift (late Aptian - latest Maastrichtian), MS4 - transgressive (latest Maastrichtian - middle Miocene) and MS5 - regressive (Middle Miocene - Holocene). Rifting by N-S orientated orthogonal extension took place in the Barremian to late Aptian. This led to the formation of two synchronous asymmetrical half-grabens named the northern and southern half-grabens. The rifting ceased in the offshore Benin Basin in the late Aptian (MSB3). This syn-rift megasequence is subdivided into three sequences which can be interpreted to represent rift onset, and rift climax phases, probably associated with the growth, linkage, and abandonment of normal fault systems. There is no evidence in these sequences for transform-related tectonics. Several short-lived episodes of contractional …
abstract: This thesis presents an evaluation of the tectonic and stratigraphic evolution of the offshore Benin Basin based on the analysis of 2D and 3D seismic data, in addition to exploration well data of four closely-spaced wells. To date, little has been published on this part of the African Equatorial Atlantic margin because of the lack of publicly available datasets, and this is the first academic study to be provided with 3D seismic data from this basin. The aims of the study were to establish a tectono-sequence stratigraphic framework for the basin, and to establish the timing, distribution, and nature of tectonic and gravity-driven deformation events. This tectono-stratigraphic evolution was then compared to adjacent and formerly adjacent basins to better understand their significance in relation to the opening of the Equatorial Atlantic and its post-drift history. Five megasequences have been identified which relate to key tectonic phases in the basin history, and/or major changes in its genetic stratigraphic behaviour. These sequences have been subdivided into seismic sequences. The megasequences are MS1- pre-rift (Precambrian - Barremian); MS2 - syn-rift (Barremian - late Aptian); MS3 - Cretaceous post-rift (late Aptian - latest Maastrichtian), MS4 - transgressive (latest Maastrichtian - middle Miocene) and MS5 - regressive (Middle Miocene - Holocene). Rifting by N-S orientated orthogonal extension took place in the Barremian to late Aptian. This led to the formation of two synchronous asymmetrical half-grabens named the northern and southern half-grabens. The rifting ceased in the offshore Benin Basin in the late Aptian (MSB3). This syn-rift megasequence is subdivided into three sequences which can be interpreted to represent rift onset, and rift climax phases, probably associated with the growth, linkage, and abandonment of normal fault systems. There is no evidence in these sequences for transform-related tectonics. Several short-lived episodes of contractional …
author: Etobro, Israel Aruoriwo Abiodun
language: eng
date published: 2017-01-01T08:00:00Z
date modified: 2026-07-24T03:48:35Z
provider: University of Plymouth
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Plymouth