Using high-resolution aeromagnetic data to recognise and map intra-sedimentary volcanic rocks and geological structures across the Cretaceous middle Benue Trough, Nigeria

Goodluck K. Anudu, Randell A. Stephenson, David I. M. Macdonald

Research output: Contribution to journalArticle

15 Citations (Scopus)

Abstract

Recently acquired high-resolution aeromagnetic data over the Cretaceous middle Benue Trough of Nigeria have been analysed employing various edge-enhancement (magnetic derivative) methods: vertical derivatives, total horizontal derivative, analytic signal, and total horizontal derivative of tilt derivative. The study was aimed at mapping intra-sedimentary volcanic rocks and their areal extents/distribution as well as delineating geological structures, their structural trends and tectonic implications. The magnetic derivative anomaly maps produced in this project greatly enhanced the high amplitude, short-wavelength (high wavenumber) anomalies associated with the surface/near-surface intra-sedimentary volcanic rocks and associated geological structures. The maps show that volcanic rocks of Late Cretaceous to Palaeocene age are much more widespread than implied by surface geological mapping, with an areal extent of greater than 12,000 km2 in the relatively shallow subsurface. The results also highlight some known and several previously unknown geological lineaments. Rose (azimuth-frequency) plots of orientations of geological structures show trends being predominantly NE–SW, NW–SE and ESE–WNW with minor ENE–WSW and N–S trends. These main groups of structural trends are associated with the Brasiliano/Pan-African orogeny (600 ± 200 Ma) and likely predate rifting of the Gondwana supercontinent. They may have been enhanced during continental break-up in Late Jurassic to Early Cretaceous.
Original languageEnglish
Pages (from-to)625-636
Number of pages12
JournalJournal of African Earth Sciences
Volume99
Issue number2
Early online date14 Mar 2014
DOIs
Publication statusPublished - Nov 2014

Keywords

  • aeromagnetics
  • Middle Benue Trough
  • magnetic derivative
  • intra-sedimentary volcanic rocks
  • structural trends
  • Nigeria

Fingerprint Dive into the research topics of 'Using high-resolution aeromagnetic data to recognise and map intra-sedimentary volcanic rocks and geological structures across the Cretaceous middle Benue Trough, Nigeria'. Together they form a unique fingerprint.

  • Cite this