Sains Malaysiana 53(5)(2024): 1021-1031

http://doi.org/10.17576/jsm-2024-5305-04

Integrated Geophysical Models for Interpretations of Heterogeneous Subsurface Environments

(Model Geofizik Bersepadu untuk Tafsiran Persekitaran Bawah Permukaan Heterogen)

MUHAMMAD TAQIUDDIN ZAKARIA^1,*, NUR AZWIN ISMAIL², NORDIANA MOHD MUZTAZA² & MOHD FAIZ MOHAMAD ZAKI³

¹Department of Earth Sciences and Environment, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

²School of Physics, Universiti Sains Malaysia, 11800, USM, Penang, Malaysia

³Faculty of Civil Engineering and Technology, Universiti Malaysia Perlis, 02600 Arau, Perlis, Malaysia

Diserahkan: 1 Disember 2023/Diterima: 5 April 2024

Abstract

Near-surface characterization can be vulnerable to misinterpretation due to limited resolution and methodological limitations. Validation from different parameters is necessary to substantiate the results and reduce errors during interpretations. This research aims to develop an alternative integrated method of a 2-D cross-plot model to enhance subsurface interpretations based on the model's criteria, resulting in better geological interpretation. Geophysical methods such as electrical resistivity and seismic refraction are utilized in a test model and a case study area to observe the capabilities of the integrated method approach. The goal of this study was to cluster two or more different parameters into a single model for a direct presentation of the subsurface model. This includes the characterization of subsurface properties, data integration using cross-plot analysis, and the development of a 2-D cross-plot model. This method visually represents the relationship between two or more attributes, allowing for the identification of anomalies. In the test model, the lithology consists of sandy silt derived from granitic residual soil, whereas in the case study model, it was dominated by weathered granitic residual soil with the presence of saturated zones. The 2-D cross-plot model provides a comprehensive interpretation where Quadrant, Q1 shows the vulnerable zones for sliding mass bodies. The plane weakness was successfully identified based on the cross-plot model as the weathered zone, and subsurface features were determined. The estimated volume of mass movement was successfully calculated for the case study area based on the determination of the sliding plane. The integrated method of cross-plot analysis along with the development of 2-D cross-plot models proves to be an informative approach for subsurface characterization and enhances subsurface imaging.

Keywords: Creep; cross-plot; resistivity; seismic refraction

Abstrak

Pencirian permukaan cetek boleh terdedah kepada salah tafsir disebabkan oleh resolusi terhad dan had metodologi. Pengesahan daripada parameter yang berbeza diperlukan untuk mengesahkan keputusan dan mengurangkan ralat semasa tafsiran. Penyelidikan ini bertujuan untuk membangunkan kaedah alternatif bersepadu bagi model plot-silang 2-D untuk meningkatkan tafsiran subpermukaan berdasarkan kriteria model, menghasilkan tafsiran geologi yang lebih baik. Kaedah geofizik seperti keberintangan elektrik dan seismik pembiasan digunakan dalam model ujian dan kawasan kes kajian untuk memerhatikan keupayaan pendekatan kaedah bersepadu. Matlamat kajian ini adalah untuk mengelompokkan dua atau lebih parameter berbeza ke dalam satu model untuk persembahan langsung model subpermukaan. Ini termasuk pencirian sifat subpermukaan, penyepaduan data menggunakan analisis plot-silang dan pembangunan model plot-silang 2-D. Kaedah ini secara visual mewakili hubungan antara dua atau lebih atribut, membolehkan untuk mengenal pasti anomali. Dalam model ujian, litologi terdiri daripada pasir berlodak daripada tanih baki granit manakala dalam kajian kes, ia didominasi oleh tanih baki granit terluluhawa dengan kehadiran zon tepu. Model plot-silang 2-D menyediakan tafsiran yang komprehensif dengan kuadran, Q1 menunjukkan zon terdedah untuk badan jisim gelongsor. Kelemahan satah telah berjaya dikenal pasti berdasarkan model plot-silang sebagai zon terluluhawa dan ciri subpermukaan telah ditentukan. Anggaran isi padu pergerakan jisim berjaya dihitung untuk kawasan kes kajian berdasarkan penentuan satah gelongsor. Kaedah bersepadu analisis plot-silang bersama-sama dengan pembangunan model plot-silang 2-D terbukti sebagai pendekatan bermaklumat untuk pencirian bawah permukaan dan meningkatkan pengimejan subpermukaan.

Kata kunci: Keberintangan; plot-silang; rayapan; seismik pembiasan

RUJUKAN

Abdelrahman, K., Ibrahim, E., Qaysi, S., Mogren, S., Zaidi, F. & Ghrefat, H. 2021. Evaluation of kinetic moduli and soil competence scale of soil profiles in Jizan area, southwestern Saudi Arabia. Arabian Journal of Geosciences 14: 1-19.

Austin, O.E., Agbasi, O.E., Samuel, O. & Etuk, S.E. 2018. Cross plot analysis of rock properties from well log data for gas detection in Soku field, Coastal Swamp Depobelt, Niger Delta Basin. Journal of Geoscience, Engineering, Environment, and Technology 3(4): 180-186.

Fat-Helbary, R.E.S., El-Faragawy, K.O. & Hamed, A. 2019. Soil geotechnical characteristics for seismic risk mitigation at the southern extension of Marsa Alam city, Egypt. NRIAG Journal of Astronomy and Geophysics 8(1): 1-14.

Fisseha, S., Mewa, G. & Haile, T. 2021. Refraction seismic complementing electrical method in subsurface characterization for tunneling in soft pyroclastic, (a case study). Heliyon 7(8): 1-9.

Hayashi, K. & Konishi, C. 2010. Joint use of a surface–wave method and a resistivity method for safety assessment of levee systems. ASCE: Geo Florida. pp. 1340-1349. http://dx.doi.org/10.1061/41095(365)134

Igwe, O. 2015. The geotechnical characteristics of landslides on the sedimentary and metamorphic terrains of South-East Nigeria, West Africa. Geoenvironmental Disasters 2(1): 1-14.

Inazaki, T. & Hayashi, K. 2011. Utilization of integrated geophysical surveying for the safety assessment of levee systems. Symposium on Applications of Geophysics to Environmental and Engineering Problems (SAGEEP), Charleston, South Carolina, 10-14 April.

Kayode, J.S., Arifin, M.H. & Nawawi, M. 2019. Characterization of a proposed quarry site using multi-electrode electrical resistivity tomography. Sains Malaysiana 48(5): 945-963.

Loke, M.H. 2015. Tutorial 2-D and 3-D electrical imaging surveys; Geotomo Software: Penang, Malaysia. p. 187.

Marcato, G., Mantovani, M., Pasuto, A., Zabuski, L. & Borgatti, L. 2012. Monitoring, numerical modelling and hazard mitigation of themoscardo landslide (Eastern Italian Alps). Engineering Geology 128: 95-107.

Noviyanto, A., Sartohadi, J. & Purwanto, B.H. 2020. The distribution of soil morphological characteristics for landslide-impacted Sumbing Volcano, Central Java-Indonesia. Geoenvironmental Disasters 7(1): 1-19.

Pazzi, V., Morelli, S. & Fanti, R. 2019. A review of the advantages and limitations of geophysical investigations in landslide studies. International Journal of Geophysics 2019: 2983087.

Rahman, C.A. & Mohamed, K.R. 2001. Pemetaan awalan sumber warisan geologi Negeri Kelantan. In Geological Heritage of Malaysia (Geoheritage Mapping and Geosite Characterization), edited by Komoo, I., Tjia, H.D. & Leman, M.S. Kuala Lumpur: Lestari UMK.

Raj, J.K. 2009. Geomorphology. In Geology of Peninsular Malaysia, edited by Hutchison, C.S. & Tan, D.N.K. Kuala Lumpur: Geological Society of Malaysia. pp. 5-29.

Tate, R.B., Tan, D.N.K. & Ng, T.F. 2009. Geological map of Peninsular Malaysia. In Geology of Peninsular Malaysia, edited by Hutchison, C.S. & Tan, D.N.K. Kuala Lumpur: Geological Society of Malaysia.

Whiteley, J.S., Watlet, A., Uhlemann, S., Wilkinson, P., Boyd, J.P., Jordan, C., Kendall, J.M. & Chambers, J.E. 2021. Rapid characterisation of landslide heterogeneity using unsupervised classification of electrical resistivity and seismic refraction surveys. Engineering Geology 290: 106189.

Yalcin, A. 2007. The effects of clay on landslides: A case study. Applied Clay Science 38(1-2): 77-85.

Yordkayhun, S. 2021. Geophysical characterization of a sinkhole region: A study toward understanding geohazards in the karst geosites. Sains Malaysiana 50(7): 1871-1884.

Zaid, H.A.H., Arifin, M.H., Kayode, J.S. & Iswadi, M.B., 2023. Application of 2-D electrical resistivity imaging, and induced polarization methods for delineating gold mineralization at Felda Chiku 3, Kelantan, Malaysia. Sains Malaysiana 52(1): 305-320.

Zakaria, M.T., Mohd Muztaza, N., Zabidi, H., Salleh, A.N., Mahmud, N. & Rosli, F.N. 2022. Integrated analysis of geophysical approaches for slope failure characterization. Environmental Earth Sciences 81(10): 299.

*Pengarang untuk surat-menyurat; email: taqiuddin@ukm.edu.my