Mapping of subsurface structural features in some parts of Anambra Basin, Nigeria, using aeromagnetic data

Abstract

Aeromagnetic data of some parts of Anambra Basin, Nigeria, covering Illushi, Nsukka, Igumale, Onitsha, Udi and Nkalagu areas were digitally processed, analyzed and interpreted qualitatively and quantitatively. The study was carried out to delineate the subsurface structural lineaments/trends that provide the locales for mineral deposit and hydrocarbon resources and to estimate the depth to magnetic sources/sedimentary thickness of the area. The data were qualitatively interpreted using reduction to equator-inverted (RTE_INV), vertical derivatives (VD), tilt derivative (TDR) filter, lineament density filter and Rose plot. Quantitative interpretation was done using source parameter imaging and Euler deconvolution methods. The results depicted that the study area has enormous structural lineaments especially in the northeast and northwest that showed a high cluster of these lineaments. The results showed that the trends of the structural lineaments have a dominance of NE-SW direction, with ancillary trends in E-W, NW-SE, N-S, NNE-SSW and ENE-WSW directions. The SPI depth result ranges from 318.45 m for shallow magnetic sources to − 11,253 m for sedimentary thickness. The 3D Euler deconvolution depth estimate revealed depths to magnetic sources ranging from − 400 to − 4300 m. The results show good evidence of the presence of the essential factors for the exploration of both mineral deposits and hydrocarbon resources in the study area.

Modeling and Estimation of Sedimentary Thickness for Hydrocarbon and Other Minerals Prospecting Within the Lower Benue Trough, Nigeria Using Airborne Geophysical Data

“…The results of this research work is in fair agreement with other previous researchers (Ezeh and Ugwu, 2010;Onu et al, 2011;Onuba et al, 2011;Igwesi and Umego, 2013;Ezema et al, 2014;Obiora et al, 2016;Edeh et al, 2017;Oguama et al, 2021;Ekwueme et al, 2017;Okorie et al, 2019 etc. ) who worked in the Lower Benue trough.…”

Structural interpretation of the south-western flank of the Anambra Basin (Nigeria) using satellite-derived WGM 2012 gravity data

“…1a, Obaje, 2009). During the last few decades, due to its high potential for hydrocarbon exploration, the basin has attracted a variety of studies that used a wide range of geological and geophysical methods (Agagu and Adighije, 1983;Cratchley et al, 1984;Benkhelil, 1989;Onwuemesi, 1997;Abbass and Mallam, 2013;Adetona and Abu, 2013;Obiora et al, 2015;Abdullahi and Singh, 2018;Ekwueme et al, 2018;Obasi et al, 2018;Okorie et al, 2019;Oguama et al, 2020). A first power spectrum analysis of magnetic data showed varying thicknesses of sedimentary deposits within the basin between 0.9 and 5.6 km (Onwuemesi, 1997).…”

“…The Ubiaja and Illushi regions have a NE-SW structural trend of magnetic anomalies with depths varying between 3 and 5.5 km (Okorie et al, 2019). Most recently, Oguama et al (2020) used magnetic data to study the structural lineaments at the eastern margin of the Anambra Basin. The majority of these lineaments are oriented in a NE-SW direction.…”

“…The majority of these lineaments are oriented in a NE-SW direction. Similar to Oguama et al (2020), previous studies on the Anambra Basin's lineaments mostly used the delineation magnetic method. In contrast, very few gravity studies are available on the basin (Agagu and Adighije, 1983;Obasi et al, 2018).…”