Estimating the Thickness of Sedimentation within Lower Benue Basin and Upper Anambra Basin, Nigeria, Using Both Spectral Depth Determination and Source Parameter Imaging

Abstract

The Total Aeromagnetic Data covering the study area was subjected to First Vertical Derivative, Spectral Depth Analysis, and Source Parameter Imaging (SPI). The result from the First Vertical Derivative shows that the Northern part of the area is covered by the young biotite granite of Precambrian origin, and the western edge is covered by the old granite, gneisses, and migmatite of Western Nigeria, while the remaining area is covered by the cretaceous sedimentary deposits. The entire area was divided into forty-eight sections. Spectral Depth Analysis was run for each of these forty-eight sections; the result shows that a maximum depth above 7 km was obtained within the cretaceous sediments of Idah, Ankpa, and below Udegi at the middle of the study area. Minimum depth estimates between 188.0 and 452 meters were observed around the basement regions. Results from Source Parameter Imaging show a minimum depth of 76.983 meters and a maximum thickness of sedimentation of 9.847 km, which also occur within Idah, Ankpa, and Udegi axis. The disparity observed in depth obtained by each method is discussed based on the merit and demerit of each method, and the depths obtained were compared with results from previous researchers. Geophysical implication of the result to oil and gas exploration in the area is briefly discussed.

Interpretation of aeromagnetic data over some parts of Mambilla Plateau, Taraba State

“…This has two advantages; 1) it eliminates errors caused by the lines of survey that are not perpendicularly oriented to the strike and secondly, it has no dependency on an operator size or user selected window other techniques like Euler methods and Naudy (1970) requires. Furthermore, output quantities grids can be generated and subsequently, image can be processed to enhance detail of structural information that otherwise may not be evident (Abbas and Mallam, 2013).…”

“…Using SPI method, grids solutions show the edge location, susceptibility contrast, dips and depths. This method requires first and second order derivatives thus making it susceptible to both interference effects and noise in the data (Abbas and Mallam, 2013).…”

Environmental assessment of gully erosion in parts of Enugu north, Southeastern Nigeria

“…The geology of Enugu north falls under Anambra Basin which consist of six major rock formations; Enugu shale, Agwu shale, Mamu formation, Ajali formation, Nsukka formation and Imo shale formation. These rocks are grouped into four formations namely: Mamu formation, Ajali Sandstone, Nsukka Formation, and Imo Shale Formation as inferred by (25) . Sediments deposited within this time interval occur in four distinct physiographic provinces, namely the Cross River plains, the Escarpment, the Plateau and the Anambra Plains.…”

Improving the Geological Understanding of the Niger Delta Basin of Nigeria Using Airborne Gravity Data

“…Also the source parameter imaging method (Abbass and Mallam, 2013) was applied to locate and estimate the depths of anomalous sources and depths to basement by calculating the horizontal grids, applying a cut off depth consistent with geology of area and then obtaining the SPI grid. All these were archived using Oasis Montaj TM software.…”