Euler Deconvolution and Two-Dimensional Modeling of Subsurface © 2020 Dzukogi AN, Et Al
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DOI: 10.35840/2631-5033/1838 Interna�onal Journal of VIBGYOR Earth Science and Geophysics Euler Deconvolution and Two-Dimensional Modeling of Subsurface Structures over Part of Northern Bida Basin and its Surrounding Basement Research Article: Open Access Rocks, Northwest, Nigeria Using Magnetic Method ISSN: 2631-5033 Abubakar Nda'asabe Dzukogi1*, Yusuf Abubakar Sanusi1, Sabiu Bala Muhammad1 and Kazeem Salako Adeyinka2 1Usmanu Danfodiyo University Sokoto, Nigeria 2Federal University of Technology Minna, Nigeria Abstract Euler deconvolution and two-dimensional modeling over part of Northern Bida Basin and its surrounding basement rocks, using aeromagnetic data was carried out in this research study. The study area is bounded by latitude 9° 00′ - 10° 30′ and longitude 5° 00′ - 7° 00′ with total area of 36,300 km2. The magnetic data was processed using Oasis montaj to produce the total magnetic intensity (TMI) data The TMI data was reduced to equator (RTE). The polynomial filter was applied on the RTE grid to performed regional residual separation. The residual data obtained was subjected to euler depth evaluation and two-dimensional modeling. The depth to the subtle magnetic anomalies and basement rock evaluated from euler deconvolution ranged from 3.083 m to 12.6 m. The highest thickness of sedimentary rocks in the study area was observed around Fashe, Mokwa, Egbako and Bida at the west, southwest and southern part of the study area. The profiles labeled AA, BB, CC, and DD were carefully drawn to cut across major strike in the study area. The result obtained from standard euler deconvolution was used as depth constrain for modeling the residual magnetic field anomalies. The result obtained from modeling shows average depth to the basement/basement structure. The depth was found to be high reaching a depth of about 3.1 km around Fashe, Mokwa and Egbako in southwestern part of the study area. This depth and the prevailing fracture/fault in the area could influence the accumulation of hydrocarbon in the study area. The average depth to the subtle magnetic source target (magnetic minerals) around Wushishi/Zungeru, Maiwayo and Paiko were suggested to be 12.8 m. Keywords Subtle, Estimation, Maximum, Euler depth, Factor and Deposit Introduction part of Nigeria is underlain by basement rocks rich in solid minerals, the search for solid minerals have The crash of crude oil price in the oil market has not been given adequate attention. Thus, there is drawn the attention of stakeholders to the non-oil a gap in solid mineral information across the coun- revenue sector of Nigeria [1]. Despite the larger try. Currently, Nigeria solid mineral sector contrib- *Corresponding author: Abubakar Nda'asabe Dzukogi, Usmanu Danfodiyo University Sokoto, Nigeria Accepted: December 08, 2020; Published: December 10, 2020 Copyright: © 2020 Dzukogi AN, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Dzukogi et al. Int J Earth Sci Geophys 2020, 6:038 Citation: Dzukogi AN, Sanusi YA, Muhammad SB, Adeyinka KS (2020) Euler Deconvolution and Two-Dimensional Modeling of Subsurface Structures over Part of Northern Bida Basin and its Surrounding Basement Rocks, Northwest, Nigeria Using Magnetic Method. Int J Earth Sci Geophys 6:038 Dzukogi et al. Int J Earth Sci Geophys 2020, 6:038 ISSN: 2631-5033 | • Page 2 of 11 • utes less than 1% to the Gross Domestic Product precise depth to the subtle target (mineralized po- (GDP) Ministry of Mines and Steel Development tential areas). Among the techniques were model- [2]. The knowledge of the structural architecture ing and euler deconvolution. of mineralized zones, the distribution and orienta- The euler deconvolution and two-dimensional tion of faults/fractures and shear zones; their for- modeling of aeromagnetic data over Northern part mation and possible reactivation during the struc- of Bida basin and its surrounding basement rocks tural revolution and tectonic condition is a key to was used to differentiate and characterize regions understanding the formation, origin and location of sedimentary thickness from those of very shal- of mineral deposits as well as exploration and find- low basement terrain. These were also used to de- ing a new target [3]. In view of environmental pol- termine the depths to the magnetic sources. The lution associated with oil exploration and decline result is used to suggest whether or not the study in the exploration of solid minerals in Nigeria, it is area has the potential for oil/gas and solid mineral prudent to explore solid mineral deposit for hu- potential. The study area is bounded by latitude 9° man consumption and safety environment. Inter- 00' N to 10° 30' N and longitude 5° 00' E to 7° 00' E pretation of potential data involves the numerical located within Niger state Northwest, Nigeria (Fig- estimate of shape, volume and depth to the sub- ure 1). The study area have an area of 36,300 km2 tle magnetic anomaly. This study focuses on the covered by 12 aeromagnetic maps. magnetic interpretation, depth to the basement rock and mineralized fracture/fault that caused the Geologic Setting of the Study Area magnetic anomaly; all were estimated through dif- The study area fall within the central part of the ferent techniques. This was toward achieving the Northwestern part of Nigeria (Figure 1). The ma- Figure 1: Geologic map of Nigeria Showing the Schist belt and location of the study area [15]. Citation: Dzukogi AN, Sanusi YA, Muhammad SB, Adeyinka KS (2020) Euler Deconvolution and Two-Dimensional Modeling of Subsurface Structures over Part of Northern Bida Basin and its Surrounding Basement Rocks, Northwest, Nigeria Using Magnetic Method. Int J Earth Sci Geophys 6:038 Dzukogi et al. Int J Earth Sci Geophys 2020, 6:038 ISSN: 2631-5033 | • Page 3 of 11 • Figure 2: Geologic map of the study area (Modified from [16]). jor towns in this area are Kontagora, Bomi, Tegina, the schist belt [9]. The study area is bounded at the Alawa, Fashe, Akerre, Wushishi, Zungeru, Minna, southwest and southeast by the Cretaceous sedi- Mokwa, Egbako, Bida and Paiko. The geology of the ment of Nupe Basin (Figure 2). study area can be viewed in terms of two principal Materials and Methods lithologic units, the oldest unit consists of Precam- brian Basement rocks at the northeast, southeast The materials used in this research study include and Northwestern part of the study area while the high resolution aeromagnetic data of sheet 140- second unit consists of Cretaceous to recent sed- 143, sheet 161-164 and sheet 182-185 covering imentary rocks (sandstone, silt and clay) of Bida the study area. The magnetic data was collected by basin which overlie the Precambrian basement FUGRO airborne services for Nigeria geological sur- unconformable at the southwestern part of the vey agency between. The data was flown at a mean study area (Figure 2). The Cretaceous sediment of terrain clearance of 80 m and profile line spacing Bida Basin was dipping to the southwest reaching of 500 m [10]. The magnetic data was analyzed a thickness of 1.72 km and 3.24 km [4-6]. The Cre- using Oasis montaj version 8.3 for the production taceous to recent sediment of the study area con- of total magnetic intensity (TMI) map of the study sist of Sakpe iron stone formation, Enagi silt stone, area. The data was reduced to equator and further Batati iron stone and Bida formation. analyzed using different methods such as euler de- convolution and modeling, suitable to achieve the The schist belt (metasediment and metavolca- designed objectives. nic) that overlie the basement rocks of Nigeria (Fig- ure 2) were dominant in the northeast and few in Euler deconvolution was applied to estimate the northwest and central part of the study area. the sedimentary thickness and depth to the subtle The schist belt was intruded by fine to coarse grain magnetic source in the study area. This method in- granite rocks (Figure 2). The schist belt boundaries volves setting an appropriate structural index (SI) have been described as metamorphic front, Mylon- value of one (1) and using least-squares inversion ite and rift bounding faults [7]. The basement rocks to solve the equation for an optimumo, x yo, zo and were characterized by granite to granodiorite and B. This technique is based on the Euler homogene- amphibolite rocks [8]. The major structural trend in ity equation [11]. The magnetic field and it gradient the basement rock in Nigeria is essentially north- is related to the location of the source of an anom- east - southwest and follows the tectonic grain of aly, with the degree of homogeneity expressed as Citation: Dzukogi AN, Sanusi YA, Muhammad SB, Adeyinka KS (2020) Euler Deconvolution and Two-Dimensional Modeling of Subsurface Structures over Part of Northern Bida Basin and its Surrounding Basement Rocks, Northwest, Nigeria Using Magnetic Method. Int J Earth Sci Geophys 6:038 Dzukogi et al. Int J Earth Sci Geophys 2020, 6:038 ISSN: 2631-5033 | • Page 4 of 11 • Figure 3: Total field magnetic map of the study area. a structural index. The relationship is expressed as represents all the magnetic effect in the area. There [11]. are variations in magnetic intensity values which dT dT dT suggest a wide variety of different magnetic prop- (x- x) +-( y y) +-( z z) = NB( - T) (1) odx oo dy dz erties. The regions with high magnetic effect were denoted with (H) and areas with low magnetic ef- Where (xo, yo, zo) is the position of the magnetic source whose total magnetic field (T) is detected fect were denoted with (L).