Estimation of Magnetic Contact Location and Depth of Magnetic Sources in a Sedimentary Formation

Alabi, A. A.; Makinde, V.; Adewale, A.O.; Coker, J. O.; Aluko, Taiwo J.

doi:10.2478/rmzmag-2019-0007

Cited by 2 publications

(2 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Magnetic data can be acquired on ground, in air, and in marine; however, the regional study requires aeromagnetic data. Aeromagnetic data is an essential tool in delineation of Basement rocks and estimation of depth to magnetic sources, even in sedimentary terrain without being disturbed by obstacles [61][62][63][64].…”

Section: Methodsmentioning

confidence: 99%

Aeromagnetic mapping of fault architecture along Lagos–Ore axis, southwestern Nigeria

Oladejo¹,

Adagunodo

Sunmonu

et al. 2020

Open Geosciences

View full text Add to dashboard Cite

A seismic wave is released when there is sudden displacement on a fault plane. The passage of this wave along the fault plane or within the lithosphere could result in ground shaking or vibration at the surface of the Earth. To provide a geophysical explanation to this phenomenon, the high-resolution aeromagnetic data of the sedimentary terrain and part of the Basement Complex of Southwestern Nigeria were processed and interpreted to provide fault architecture of the area, which could serve as conduit for the passage of seismic energy in the study area. High-resolution aeromagnetic data along the Lagos–Ore axis are processed for fault mapping in the study area. The reduced-to-equator (RTE) residual aeromagnetic data used were enhanced using the total horizontal derivative (THD) and upward continuation (UC) filtering techniques on Oasis Montaj 6.4.2 (HJ) software. The resultant maps were overlaid and compared with the plotted RTE residual maps for relevant interpretations. Varying signatures of magnetic anomalies are grouped into high (57.9–89.1 nT), intermediate (38.2–57.9 nT), and low (4.0–38.2 nT) magnetic intensities, which are associated with contracting basement rocks features. The obtained lineaments from the THD reveal areas of various deformations such as brittle, which is associated with faults/fractures, and ductile deformation, which is associated with folds of geological features. The faults, as depict by the UC map, reveal different depth ranges of 500–2250 m at the western side and 1,500–1,250 m at the northwestern area of the study. Since it has been on record that September 11, 2009, earth tremor of magnitude 4.4, with the epicenter at Allada, Bennin Republic, 128 km west of Lagos, Nigeria occurred within the study area, it can be inferred that the established geologic fault architecture could be responsible for the hazard and be part or synthetic to the Ifewara-Zungeru fault in Nigeria.

show abstract

Section: Methodsmentioning

confidence: 99%

Aeromagnetic mapping of fault architecture along Lagos–Ore axis, southwestern Nigeria

Oladejo¹,

Adagunodo

Sunmonu

et al. 2020

Open Geosciences

View full text Add to dashboard Cite

show abstract

“…It has a heterogeneous assemblage comprising migmatites, orthogenesis, paragneisses, and a series of basic and ultra basic metamorphosed rocks. The Schist Belts comprise low grade, Meta sediment-dominated belts trending N-S which are best developed in the western part of Nigeria (Onwuemesi, 1997;Mukaila et al, 2019;Alabi et al, 2019;Akusika et al, 2020). These belts are considered to be Upper Proterozoic supra crustal rocks which have been infolded into the migmatites-gneiss-quartzite complex.…”

Section: Location and Geology Of The Study Areamentioning

confidence: 99%

Analysis of High Resolution Aeromagnetic Data of Some Parts of Benue Trough, Nigeria

Usman¹,

Jibril

2020

FJS

View full text Add to dashboard Cite

This work is aimed to determine the depth to basement of some magnetic sources in the study area. Four aeromagnetic sheets were acquired from the Nigerian Geological Survey Agency which includes (Bajoga, 131, Gulani, 132, Gombe, 152 and Wuyo, 153). The study area covers an estimated area of about 12100km2 between latitude 90N-110N and longitude 110E-130E. The total magnetic field of the study area have been evaluated. In order to determine the basement depth, spectral analysis technique was applied. Detailed analysis of the aeromagnetic data for the study area was performed. The procedure involved in the analysis include reduction to equator to remove the effect of inclination, contouring of the total magnetic intensity, separation of the regional and residual anomalies using polynomial fitting of first order, qualitative interpretation and quantitative interpretation. The residual field of the study area composes of low magnetic anomalies reaching a minimum value of -158.6nT as observed in the northern and southern parts and high magnetic anomalies reaching a maximum value of 178.1nT as observed in the western part of the study area. The result from the spectral analysis for each block shows that the depths to the magnetic source are 5.20Km for block 1, 5.74Km for block 2, 7.59Km for block 3 and 3.56Km for block 4. The average depth to magnetic source in the study area was found to be 5.52Km. Based on the computed average sedimentary thickness obtained in this study area, hydrocarbon accumulation in the study area is feasible.

show abstract

Estimation of Magnetic Contact Location and Depth of Magnetic Sources in a Sedimentary Formation

Cited by 2 publications

References 22 publications

Aeromagnetic mapping of fault architecture along Lagos–Ore axis, southwestern Nigeria

Aeromagnetic mapping of fault architecture along Lagos–Ore axis, southwestern Nigeria

Analysis of High Resolution Aeromagnetic Data of Some Parts of Benue Trough, Nigeria

Contact Info

Product

Resources

About