MEASUREMENT AND ENHANCEMENT OF GRAVITY DATA FOR GEOPHYSICAL INVESTIGATIONS IN ABUJA, NIGERIA

  • T. Abubakar
  • E. Olumba
Keywords: Gravity anomalies, Prediction, Kriging, Interpolation, Gravity model

Abstract

The availability of gravity data is useful to individuals, governments and organizations that wish to carry out a geophysical investigation in Abuja. The data provides an accurate model for environmental monitoring and disaster studies. This research was aimed at measurement and prediction of gravity data in Abuja, Nigeria. The aim was achieved by observation of terrestrial gravity data at forty (40) gravity stations around the federal capital territory Abuja, prediction of the gravity data at other points and the evaluation of the predicted data. Gravity reduction was carried out on the measured data to account for drift correction, free air correction, bouguer correction latitude correction and terrain correction. The data was further enhanced by interpolation using the Kriging method. A total of 59 points were predicted from the 40 measured stations. The predicted gravity anomalies were validated by comparing with their corresponding gravity anomalies obtained from the Earth Gravity Model 2008 (EGM08) because of their well-established reliability. For the number of observations, n = 59, the RMSE and SE were computed as 4.797mGal (4.787x10-5 ms-2) and 4.880mGal (4.880 x10-5 ms-2) respectively. Also, the correlation value obtained was 0.991 which is significant at 0.01 level. This shows a strong relationship signifying a perfect possible agreement in the values obtained. It was therefore concluded that Kriging is a good interpolator that provides an estimate with high reliability and dependency. In this regard, considering the high cost of geophysical data collection, gravity prediction can make geophysical data collection more efficient and cost-effective.

References

Balogun, B.B. and Osazuwa, I.B., (2023). The gravity field and gravity data reduction across the continental area of Nigeria. Geodesy and Geodynamics (Elsevier), 14, 304-320 DOI: https://doi.org/10.1016/j.geog.2022.09.003

Dawod, D. M., (1998). A National Gravity Standardization Network for Egypt. Published Ph.D. dissertation of the Department of Surveying Engineering, Shoubra Faculty of Engineering. Zagazig University. http://www.academia.edu/794554/The_egyptian_national_gravity_standardization_network_ENGN97_. Accessed 15th February, 2021

Ellman A., Vanicek P., Santos M. and R. Kingdon, (2007). “Interrelation between the geoid and Exploration.

Eteje, S. O., Oduyebo O. F. and Oluyori P D. (2019). Modelling Local Gravity Anomalies from Processed Observed Gravity Measurement for Geodetic Applications. International Journal of Scientific Research in Science and Technology (IJRST), Vol. 6, No. 5, PP 144-162. DOI: https://doi.org/10.32628/IJSRST196515

Idowu T. O. (2006). Prediction of Gravity Anomalies for Geophysical and Exploration. FUTY Journal of the Environment, Yola-Nigeria Vol. 1 No.1, July 2006 DOI: https://doi.org/10.4314/fje.v1i1.50776

Jassim, F. A. and Altaany, F. H. (2013). Image Interpolation Using Kriging Technique for Spatial Data. Canadian Journal on Image Processing and Computer Vision, Vol. 4, No. 2, pp 16-21.

Kearey, P. and Brooks, M. (1988). An Introduction to Geophysical Exploration. The Garden City, Blackwell Scientific Press, Letchworth, Herts.

Mandal A. Biswas A. Mittal S. Mohanti W.k., Sharma S. P., Sengupta D., Sen J., Bhatt A.K. (2013). Geophysical Anomalies Associated with Uranium Mineralization from Beldih Mine, South Perugia Shear Zone India. J. Geol Soc.ind 82(6):601-606 DOI: https://doi.org/10.1007/s12594-013-0197-1

Mathews, L. R., Mclean, M. A. (2015). Gippsland Basin Gravity Survey. Geological Survey of Victoria Technical Record. http://earthresources.vic.gov.au/_data/assets/pdf_file/0011/456743/G6-Gippsland-gravity-survey-report-june-2015.pdf . Accessed 23 February 2021.

Mundi, R., (2000). “Population of the FCT” in Geography of the Federal Capital Territory. Dawam, P.D. (eds). Minna. Famous Ashanlu publishers. Pp70-84.

Murray, A. S., Tracey, R. M. (2001). Best Practice in Gravity Surveying. Australian Geological Survey Organization. https://d28rz98at9flks.cloudfront.net/37202/37202.pdf . Accessed 23 February, 2021.

National Population Commission (2006). Population and Housing Census of the Federal Republic of Nigeria.

Nnaji, O.A., Udensi, E.E., Unuevho, C., Lawrence, J.O. and Salako, K.A., (2021). Estimation of the depth to Moho of parts of North Central Nigeria using Bougher gravity data. Journal Of Science, technology, mathematics and education, (JOSTMED) 17, (12), 35-43.

Nabighian, M.N., Ander, M.E., Grauch, V.J.S., Hansen, R.O., LaFehr, T.R., Li, Y.1 , Pearson, W.C., Peirce, J.W., Phillips, J.D. , and Ruder, M.E. (2005), The Historical Development of the Gravity Method in Exploration VL70 DO - 10.1190/1.2133785 Geophysics DOI: https://doi.org/10.1190/1.2133785

Osazuwa, I. B. (1995). Nigeria gravity network project: achievements and challenges. Proceedings of the second Regional Geodesy and Geophysics Assembly in Sweden.

Ozturk, D. and Kilic, F. (2016). Geostatistical Approach for Spatial Interpolation of Meteorological Data. Anais da Academia Brasileira de Ciências, Vol. 88, No. 4, pp 2121- 2136. DOI: https://doi.org/10.1590/0001-3765201620150103

Raynolds, J. M. (2011). “An Introduction to Applied and Environmental Geophysics. Geophysics (2nd ed). Published by John Wiley & Sons Ltd. West Sussex, England.

Transparency for Nigeria (2011). About Nigeria, Abuja, FCT. Transparency for Nigeria. Available online at www.http// transparencyng.com/index.php?option

Van-Beers, W. C. M. and Kleijnen, J. P. C. (2003). Kriging for Interpolation in Random Simulation. Journal of the Operational Research Society, Vol. 54, pp. 255–262. In Jassim, F. A. and Altaany, F. H. (2013). Image Interpolation Using Kriging Technique for Spatial Data. Canadian Journal on Image Processing and Computer Vision, Vol. 4, No. 2, pp 16-21. DOI: https://doi.org/10.1057/palgrave.jors.2601492

Wei Liang, Jiancheng Li, Xinyu Xu, Shengjun Zhang, Yongqi Zhao, (2020,) A High-Resolution Earth’s Gravity Field Model SGG-UGM-2 from GOCE, GRACE, Satellite Altimetry, and EGM2008, Engineering, Volume 6, Issue 8, Pages 860-878,ISSN 2095-8099, https://doi.org/10.1016/j.eng.2020.05.008. (https://www.sciencedirect.com/science/article/pii/S2095809919305661) DOI: https://doi.org/10.1016/j.eng.2020.05.008

Yilmaz, M. and Kozlu, B. (2018). The Comparison of Gravity Anomalies Based on Recent High-Degree Global Models. Afyon Kocatepe University Journal of Science and Engineering, Vol. 18, pp 981-990. DOI: https://doi.org/10.5578/fmbd.67502

Published
2024-04-30
How to Cite
AbubakarT., & OlumbaE. (2024). MEASUREMENT AND ENHANCEMENT OF GRAVITY DATA FOR GEOPHYSICAL INVESTIGATIONS IN ABUJA, NIGERIA. FUDMA JOURNAL OF SCIENCES, 8(2), 267 - 276. https://doi.org/10.33003/fjs-2024-0802-2362