Selection of an optimum global gravitational model for geological mapping of Afikpo and Anambra Basins in Nigeria

    Ojima Isaac Apeh   Affiliation
    ; Robert Tenzer   Affiliation


Combined Global Gravitational Models (GGMs) are being used in numerous geoscience applications, most notably for gravimetric geoid modeling (in geodesy) and for geological mapping and geophysical explorations (in the Earth’s sciences). The aim of this study is to evaluate the suitability of different combined GGMs that could be used for the geological mapping of middle belt region and Southeastern Nigeria. For this purpose, we digitized geological maps of Afikpo and Anambra Basins to evaluate geological signatures implied by gravity field quantities (Bouguer gravity anomalies and vertical gravity gradient) derived from the EGM2008, EIGEN-6C4, GECO, SGG-UGM-1 and XGM2019e_2159 gravitational models. We also stochastically evaluated the performance of these GGMs by computing their Root-Mean-Square (RMS) fit with ground-based gravity measurements. The results show that the EIGEN-6C4 and XGM2019e_2159 models have the best RMS fit with the ground-based gravity data. A spatial pattern in Bouguer gravity maps (compiled using these two models) generally closely agrees with a geological configuration of the basins, while also exhibiting some more detailed geological features. Interestingly, however, despite the XGM2019e has the best fit and better mimics major geological features, the gravity image from this model does not exhibit a sediment signature in a portion of the Afikpo basin. A possible reason is that the topographic information used to recover a higher-frequency gravity spectrum of this model might suppress a gravitational signature of subsurface density structures. A comprehensive interpretation of geological features thus requires a careful analysis of existing GGMs, terrestrial gravity data as well as all other reliable geological and geophysical information.

Keyword : bouguer/free-air gravity anomalies, geological mapping, GGMs, gravity gradient, gravimetric interpretation

How to Cite
Apeh, O. I., & Tenzer, R. (2022). Selection of an optimum global gravitational model for geological mapping of Afikpo and Anambra Basins in Nigeria. Geodesy and Cartography, 48(2), 92–106.
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Jun 29, 2022
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Akaegbobi, M. I. (2005). Sequence stratigraphy of Anambra Basin. Journal of African Earth Sciences, 42, 394–406.

Amajor, L. C. (1987). Paleocurrent, petrography and provenance analysis of the Ajali Sandstone (Upper Cretaceous), south Benue Trough, Nigeria. Sedimentary Geology, 54, 47–60.

Anakwuba, E. K., Ajaegwu, N. E., Ejeke, C. F., Onyekwelu, C. U., & Chinwuko, A. I. (2018). Sequence stratigraphic interpretation of parts of Anambra Basin, Nigeria using geophysical well logs and biostratigraphic data. Journal of African Earth Sciences, 139, 330–340.

Andersen, O., Knudsen, P., & Stenseng, L. (2015). The DTU13 MSS (Mean Sea Surface) and MDT (Mean Dynamic Topography) from 20 years of satellite altimetry. In S. Jin, R. Barzaghi (Eds.), International Association of Geodesy Symposia: Vol. 144. IGFS 2014 (pp. 111–121). Springer.

Apeh, O. I., Moka, E. C., & Uzodinma, V. N. (2018). Evaluation of gravity data derived from global gravity field models using terrestrial gravity data in Enugu State, Nigeria. Journal of Geodetic Science, 8(1), 145–153.

Bagherbandi, M., & Sjöberg, L. E. (2013). Improving gravimetric–isostatic models of crustal depth by correcting for non-isostatic effects and using CRUST2. 0. Earth-Science Reviews, 117, 29–39.

Barthelmes, F., & Köhler, W. (2016). The Geodesists Handbook 2016. Journal of Geodesy, 90(10), 907–1205.

Barthelmes, F. (2013). Definition of functionals of the geopotential and their calculation from spherical harmonic models: Theory and formulas used by the calculation service of the International Centre for Global Earth Models (ICGEM), (Scientific Technical Report STR09/02, Revised ed.). Helmholtz-Zentrum Potsdam, GFZ German Research Centre for Geosciences.

Bouman, J., Ebbing, J., Fuchs, M., Sebera, J., Lieb, V., Szwillus, W., Haagmans, R., & Novak, P. (2016). Satellite gravity gradient grids for geophysics. Scientific Reports, 6(1), 21050.

Brockmann, J. M., Zehentner, N., Höck, E., Pail, R., Loth, I., Mayer‐Gürr, T., & Schuh, W. D. (2014). EGM_TIM_RL05: An independent geoid with centimeter accuracy purely based on the GOCE mission. Geophysical Research Letters, 41(22), 8089–8099.

Chen, W., & Tenzer, R. (2017). Moho modeling in spatial domain: A case study under Tibet. Advances in Space Research, 59(12), 2855–2869.

Chouhan, A. K., Singh, D., Pal, S. K., & Choudhury, P. (2022). Delineation of subsurface geological fractures in the Cambay rift and surrounding regions of NW India: An integrated approach using satellite derived EIGEN-6C4 gravity data. Geocarto International, 37(1), 268–283.

Cratchley, C. R., & Jones, J. P. (1965). An interpretation of the geology and gravity anomalies of The Benue Valley, Nigeria. Overseas Geological Surveys.

Dogru, F., Pamukcu, O., Gonenc, T., & Yildiz, H. (2018). Lithospheric structure of western Anatolia and the Aegean Sea using GOCE-based gravity field models. Bollettino di Geofisica Teorica ed Applicata, 59(2).

Drinkwater, M. R., Floberghagen, R., Haagmans, R., Muzi, D., & Popescu, A. (2003). GOCE: ESA’s first earth explorer core mission. In G. Beutler, M. R. Drinkwater, R. Rummel, & R. Von Steiger (Eds.), Earth gravity field from space-from sensors to earth science (pp. 419–432). Springer.

Ekwere, A. S., Edet, A. E., & Ekwere, S. J. (2012). Groundwater chemistry of the oban Massif, south-eastern Nigeria. Revista Ambiente & Água, 7(1), 51–66.

Floberghagen, R., Fehringer, M., Lamarre, D., Muzi, D., Fromm­knecht, B., Steiger, C., Piñeiro, J., & da Costa, A. (2011). Mission design, operation and exploitation of the gravity field and steady-state ocean circulation explorer mission. Journal of Geodesy, 85(11), 749–758.

Förste, C., Bruinsma, S. L., Abrikosov, O., Lemoine, J. M., Marty, J. C., Flechtner, F., Balmino, G., Barthelmes, F., & Biancale, R. (2014). EIGEN-6C4 The latest combined global gravity field model including GOCE data up to degree and order 2190 of GFZ Potsdam and GRGS Toulouse. GFZ Data Services.

Ghomsi, F. E. K., Sévérin, N., Mandal, A., Nyam, F. E. A., Tenzer, R., Kamga, A. P. T., & Nouayou, R. (2020). Cameroon’s crustal configuration from global gravity and topographic models and seismic data. Journal of African Earth Sciences, 161, 103657.

Gilardoni, M., Reguzzoni, M., & Sampietro, D. (2016). GECO: a global gravity model by locally combining GOCE data and EGM2008. Studia Geophysica et Geodaetica, 60(2), 228–247.

Hirt, C., Rexer, M., Scheinert, M. Pail, R., Claessens, S., & Holmes, S. (2016). A new degree‐2190 (10 km resolution) gravity field model for Antarctica developed from GRACE, GOCE and Bedmap2 data. Journal of Geodesy, 90, 105–127.

Hirt, C., & Rexer, M. (2015). Earth2014: 1 arc-min shape, topography, bedrock, and ice-sheet models – Available as gridded data and degree-10,800 spherical harmonics. International Journal of Applied Earth Observation and Geoinformation, 39, 103–112.

Igwe, O., Okechukwu, N., & Adepehin, E. J. (2013). Assesment of asbestos waste dumpsite in Enugu Metropolis, South-Easthern Nigeria: implications for environmental concern. Nigeria Journal of Education, Health and Technology Research (NJEHETR), 4(4), 146–158.

Ince, E. S., Barthelmes, F., Reißland, S., Elger, K., Förste, C., Flechtner, F., & Schuh, H. (2019). ICGEM–15 years of successful collection and distribution of global gravitational models, associated services and future plans. Earth System Science Data, 11, 647–674.

Kvas, A., Mayer-Gürr, T., Krauss, S., Brockmann, J. M., Schubert, T., Schuh, W.-D., Pail, R., Gruber, T., Jäggi, A., & Meyer, U. (2019). The satellite-only gravity field model GOCO06s [Data set]. GFZ Data Services.

Liang, W. (2018). SGG-UGM-1: the high-resolution gravity field model based on the EGM2008 derived gravity anomalies and the SGG and SST data of GOCE satellite. GFZ Data Services.

Mayer-Gurr, T. (2007, October 15–17). ITG-Grace03s: The latest GRACE gravity field solution computed in Bonn [Conference presentation]. Joint International GSTM and SPP Symposium, Potsdam, Germany.

Morelli, C., Gantar, C., McConnell, R. K., Szabo, B., & Uotila, U. (1972). The international gravity standardization net 1971 (IGSN 71). Osservatorio Geofisico Sperimentale Trieste, Italy.

Nigerian Geological Survey Agency. (2017). Regional gravity survey of Enugu State.

Nigerian Geological Survey Agency. (2012). List of Geological Sheet Maps.

Nwajide, C. S. (2013). Geology of Nigeria’s Sedimentary Basins. CSS bookshops limited, Lagos.

Obi, G. C., Okogbue, C. O., & Nwajide, C. S. (2001). Evolution of the Enugu Cuesta: a tectonically driven erosional process. Global Journal of Pure Applied Sciences, 7(2), 321–330.

Odera, P. A. (2020). Evaluation of the recent high-degree combined global gravity-field models for geoid modelling over Kenya. Geodesy and Cartography, 46(2), 48–54.

Okoro, A. U., & Igwe, E. O. (2018). Lithostratigraphic characterization of the Upper Campanian–Maastrichtian succession in the Afikpo Sub-basin, southern Anambra Basin, Nigeria. Journal of African Earth Sciences, 147, 178–189.

Osazuwa, I. B. (1986). The establishment of a primary gravity Network for Nigeria [PhD thesis]. Ahmadu Bello University, Zaria, Nigeria.

Osazuwa, I. B. (1992). The Nigerian standard gravimeter calibration line. Survey Review, 31(245), 397–408.

Pal, S. K., & Kumar, S. (2019). Subsurface structural mapping using EIGEN6C4 data over Bundelkhand craton and surroundings: An appraisal on kimberlite/lamproite emplacement. Journal of the Geological Society of India, 94(2), 188–196.

Pal, S. K., Majumdar, T. J., Pathak, V. K., Narayan, S., Kumar, U., & Goswami, O. P. (2016). Utilization of high-resolution EGM2008 gravity data for geological exploration over the Singhbhum-Orissa Craton, India. Geocarto International, 31(7), 783–802.

Pappa, F., Ebbing, J., Ferraccioli, F., & van der Wal, W. (2019). Modeling satellite gravity gradient data to derive density, temperature, and viscosity structure of the Antarctic lithosphere. Journal of Geophysical Research: Solid Earth, 124(11), 12053–12076.

Pavlis, N. K., Holmes, S. A., Kenyon, S. C., & Factor, J. K. (2012). The development and evaluation of the Earth Gravitational Model 2008 (EGM2008). Journal of Geophysical Research: Solid Earth, 117(B4).

Pavlis, N. K. (2006, June 19–23). Global gravitational modeling, an overview considering current and future dedicated gravity mapping missions [Conference presentation]. IGes Geoid School 2006, The Determination and Use of the Geoid, University of Copenhangen, Denmark.

Rathnayake, S., & Tenzer, R. (2019). Interpretation of the lithospheric structure beneath the Indian Ocean from gravity gradient data. Journal of Asian Earth Sciences, 183, 103934.

Rathnayake, S., Tenzer, R., Pitoňák, M., & Novák, P. (2020). Effect of the lateral topographic density distribution on interpretational properties of Bouguer gravity maps. Geophysical Journal International, 220(2), 892–909.

Reyment, R. A. (1965). Aspects of the geology of Nigeria: the stratigraphy of the Cretaceous and Cenozoic deposits. Ibadan University Press.

Xu, X., Zhao, Y., Reubelt, T., & Tenzer, R. (2017). A GOCE only gravity model GOSG01S and the validation of GOCE related satellite gravity models. Geodesy and Geodynamics, 8(4), 260–272.

Yilmaz, M., Yilmaz, I., & Uysal, M. (2018). The evaluation of gravity anomalies based on global models by land gravity data. International Journal of Geological and Environmental Engineering, 12(11), 814–820.

Zingerle, P., Pail, R., Gruber T., & Oikonomidou, X. (2019). The experimental gravity field model XGM2019e. GFZ Data Servicer.