Assessment of Mining Lease Adequacy and Land Use Dynamics in Manganese Deposits of Vizianagaram District, South India

Document Type : Original Research Articles

Authors
1 1 Department of Geology, College of Science and Technology, Andhra University, Visakhapatnam 530003, AP, India. 2 Department of Geology, Sudan University of Science and Technology, Al-Mogran, Khartoum, Sudan.
2 1 Department of Geology, College of Science and Technology, Andhra University, Visakhapatnam 530003, AP, India.
Abstract
The study investigates the relationships among orebody geometry, stripping intensity, and adequate areal leasing in three open-cast manganese mines (A, B, and C) in the Eastern Ghats Mobile Belt of India. The deposits are hosted in high-grade metamorphic Khondalite–Charnockite assemblages and exhibit variable structural continuity, dip, and lens-shaped formation. An integrated geological–spatial assessment framework is applied, combining orebody characterization from approved mining plans with GIS-based land-use analysis and normalized efficiency metrics (stripping ratio, waste area per unit of extractable ore, ratio of undisturbed/inactive land). The results reveal that stripping intensity and surface occupation are notably near the boundaries of structural complexity and orebody discontinuity. High stripping ratios and waste intensity in Mines A and B (which exhibit irregular, pinching–swelling geometries with increased dip angles) progressively saturate their lease areas. Mine B is a spatially constrained system in which high stripping burden intersects with limited lease extent. Conversely, Mine C shows relatively high geological continuity and large untouched territory, leading to lower stripping intensity and greater operational flexibility. Rather than relying solely on regulatory limits, this analysis shows that lease adequacy is a function of coupled orebody geometry and surface land availability. Normalized spatial efficiency metrics provide a functional foundation for assessing extractability risk in structurally complex manganese deposits. Land-use assessment to create continuity in the geological picture is a key part of lease planning. This facilitates long-term material recovery and minimizes the risk of premature sterilization, particularly in high-grade metamorphic terrains.
Keywords
Subjects

1.  Guo L, Li J, Zhang C, Xu Y, Xing J, Hu J. Evaluating the impact of human activities on vegetation restoration in mining areas based on the GTWR. ISPRS International Journal of Geo-Information. 2024;13(4):132.
2.  Mefomdjo Fotie B, Dairou A, Juscar N, Romarice MF, Arsene M, Tchuikoua LB. Assessment of land cover degradation due to mining activities using remote sensing and digital photogrammetry. Environmental Systems Research. 2024;13. https://doi.org/10.1186/s40068-024-00372-5.
3.  Hazarika P, Das K, Borah G. Geology and metallogeny of manganese deposits in high-grade metamorphic terrains: A review from the Eastern Ghats Belt of India. Ore Geology Reviews. 2020; 122:103521.
4.  Roy S. Manganese Ore Deposits: Geochemistry, Mineralogy, and Genesis (2nd ed.). Springer. 2020.
5.  Awuah-Offei K, Adekpedjou A. Improving mining land-use assessment through quantitative spatial analysis. Resources Policy. 2019; 61:190–198.
6.  Samanta B, Dhar BB, Kumari A. Advances in pit slope design and volumetric estimation techniques. Mining Technology. 2021; 130:140–152.
7.  Liu Y, Li X, Zhang P. Integrating orebody geometry and operational constraints in open-pit optimization. International Journal of Mining Science and Technology. 2020; 30:495–504.
8.  Silva R, Carvalho F. Multi-criteria frameworks for sustainable mine planning. Journal of Cleaner Production. 2022; 367:32987.
9.  Saha D, Tripathy A, Bose S. Tectono-metamorphic evolution of the Eastern Ghats Mobile Belt: Implications for mineralization. Gondwana Research. 2021; 92:1–23.
10. Tripathy A, Saha D. Shear zone–controlled deformation in the Eastern Ghats Belt and its metallogenic implications. Journal of Structural Geology. 2019; 124:10–27.
11. Chakraborty S, Bose S, Bandyopadhyay D. Structural controls on manganese mineralization in high-grade metamorphic belts: Insights from the Eastern Ghats Province, India. Journal of Asian Earth Sciences. 2022; 229:105–184.
12. Kuleshov VN. Global metallogenic patterns of Precambrian manganese deposits. Precambrian Research. 2018; 307:103–118.
13. Li X, Liu Y, Wang S. Structural dismemberment and remobilization of oxide ore bodies in metamorphic terrains. Ore Geology Reviews. 2021; 134:104122.
14. Mukhopadhyay B, Banerjee R, De S. Geochemical evolution of supergene manganese oxides in Precambrian metamorphic provinces. Geochemistry: Exploration, Environment, Analysis. 2022;22(1):55–71.
15. Sharma K, Singh J, Pal D. Weathering processes and manganese oxide enrichment in Archean terrains: New insights from mineral chemistry. Applied Geochemistry. 2023; 152:105541.