GRADIENT MATTERS: MORPHOLOGICAL CONTROL ON NICKEL LATERITE QUALITY IN THE LUK ULO MÉLANGE COMPLEX, SELOGIRI, KEBUMEN REGENCY, CENTRAL JAWA
KONTROL MORFOLOGI TERHADAP KADAR NIKEL PADA KOMPLEKS MELANGE LOK ULO, DAERAH SELOGIRI, KABUPATEN KEBUMEN, JAWA TENGAH
DOI:
https://doi.org/10.47599/bsdg.v21i2.609Keywords:
Nickel laterite, Selogiri, slope gradient, Luk Ulo Mélange ComplexAbstract
Nickel laterite deposits are strategic mineral resources whose formation is controlled by multiple factors, particularly topographic morphology. This study aim to characterizes the laterite nickel deposit profile developed on ultramafic rocks of the Luk Ulo Mélange Complex in the Selogiri area,Karanggayam district, Kebumen Regency, Central Java, and examines the influence of slope gradient on nickel concentration. Methods employed include surface geological mapping over a 3.4 km² area, manual drilling using a hand auger to a depth of 4.05 m, petrographic analysis of six thin sections, and geochemical analysis of eight samples by X-Ray Fluorescence (XRF). Results indicate that the Selogiri area comprises five rock units correlated with the Late Cretaceous Luk Ulo Mélange Complex. The laterite profile consists of topsoil (0.90 m), limonite (1.80 m), and saprolite (1.35 m) zones, exhibiting a silicate-type nickel enrichment pattern. The highest Ni grade was recorded in the saprolite zone at 0.061%, well below the economic threshold. Lateritization intensity is classified as weak, attributed to steep slope gradients (16°–35°) and the relatively short exposure duration of the parent rock since the Plio-Pleistocene. Comparison with other laterite nickel deposits across Indonesia reveals a negative correlation between slope gradient and nickel grade, where gentle slopes (Class III–IV, 4°–16°) yield higher Ni grades (1.5–2.5%) compared to steep slopes. Beyond morphological control, tectonic setting and lateritization duration also significantly govern deposit quality.
References
Ahmad, W., 2008. Nickel laterites: fundamental of chemistry, mineralogy, weathering processes, formation, and exploration. Vale Inco–VITSL.
Ariyaputera, R., Basuki, N.I. and Rudyawan, A., 2025. Studi geologi dan karakteristik nikel laterit di daerah Selogiri, Kabupaten Kebumen, Jawa Tengah. Tugas Akhir Sarjana. Institut Teknologi Bandung, Bandung.
Asikin, S., Harsolumakso, A.H., Busono, H. and Gafoer, S., 1992. Geologi Lembar Kebumen, Jawa. Bandung: Pusat Penelitian dan Pengembangan Geologi.
Butt, C.R. and Cluzel, D., 2013. Nickel laterite ore deposits: weathered serpentinites. Elements, 9(2), pp.123–128.
Cathelineau, M. et al., 2024. Peridotite weathering and Ni redistribution in New Caledonian laterite profiles: influence of climate, hydrology, and structure. Minerals, 14(11), p.1082.
Choi, Y., Lee, I. and Moon, I., 2021. Geochemical and mineralogical characteristics of garnierite from the Morowali Ni-laterite deposit in Sulawesi, Indonesia. Frontiers in Earth Science, 9, p.761748.
Dalvi, A.D., Bacon, W.G. and Osborne, R.C., 2004. The past and the future of nickel laterites. In: PDAC 2004 International Convention. Toronto: Prospectors and Developers Association of Canada, pp.1–27.
Farrokhpay, S. et al., 2019. Characterization of Weda Bay nickel laterite ore from Indonesia. Journal of Geochemical Exploration, 196, pp.270–281.
Hall, R., 2012. Late Jurassic–Cenozoic reconstructions of the Indonesian region and the Indian Ocean. Tectonophysics, 570, pp.1–41.
Hall, R.A. and Wilson, M.E.J., 2000. Neogene sutures in eastern Indonesia. Journal of Asian Earth Sciences, 18(6), pp.781–808.
Haluk, H., 2025. Geochemical characteristics of laterite nickel deposits in Block A PT. Kawei Sejahtera Mining, Raja Ampat. INTAN Jurnal Penelitian Tambang, 8(1).
Harsolumakso, A.H. and Noeradi, D., 1996. Deformasi pada Formasi Karangsambung, daerah Luk Ulo, Kebumen, Jawa Tengah. Buletin Geologi, 26(1), pp.45–54.
Harsolumakso, A.H. et al., 2015. Luk Ulo Mélange Complex, Central Java: characteristics, origin and tectonic significance. In: 13th AOGS Annual Meeting, Beijing.
Hasria, H. et al., 2021. Pengaruh geomorfologi terhadap pola distribusi unsur nikel dan besi pada endapan nikel laterit di Kabupaten Buton Tengah. Jurnal Geosapta, 7(2), pp.103–114.
Hasria, H. et al., 2024. Pengaruh kemiringan lereng terhadap ketebalan endapan nikel laterit daerah Tobimeita, Konawe Utara. Jurnal Geosains dan Teknologi, 6(3), pp.174–185.
Ilham, M. et al., 2021. Pengaruh batuan dasar dan kelerengan terhadap kadar dan ketebalan nikel laterit di Morowali Utara. Jurnal Teknik Geologi, 5(1), pp.23–33.
Ilyas, A., Amin, M. and Djafar, M.T., 2016. Geokimia endapan nikel laterit di Pomalaa, Kolaka. Jurnal Geologi dan Sumberdaya Mineral, 20(2), pp.85–96.
Isjudarto, A., 2013. Pengaruh morfologi lokal terhadap pembentukan nikel laterit. In: Prosiding ReTII ke-8. Yogyakarta: ITN, pp.10–14.
Kadarusman, A. et al., 2004. Petrology and geochemistry of East Sulawesi ophiolite. Journal of Asian Earth Sciences, 22(5), pp.461–476.
Kementerian Energi dan Sumber Daya Mineral, 2024. Buka Indonesia Mining Summit, Menteri Bahlil tegaskan hilirisasi. Siaran Pers No. 646.Pers/04/SJI/2024.
Langkoke, R., 2023. Modeling and estimation of nickel laterite resources using geocomputing methods. IJSECS, 3(1), p.1090.
Le Maitre, R.W., 2002. A classification of igneous rocks. Cambridge: Cambridge University Press.
Monnier, C. et al., 1995. Back-arc basin origin for the East Sulawesi ophiolite. Geology, 23(9), pp.851–854.
Mudd, G.M., 2010. Global trends and environmental issues in nickel mining. Ore Geology Reviews, 38(1–2), pp.9–26.
Mudd, G.M. and Jowitt, S.M., 2014. Global nickel resource trends. Economic Geology, 109(7), pp.1813–1841.
Pandu, Hasria, H. and Arisona, A., 2025. Hubungan kemiringan lereng dengan kadar dan ketebalan Ni. Jurnal Riset Teknologi Pertambangan, 6(1), pp.38–45.
Qi, D.R. et al., 2024. Nickel enrichment during lateritization of ophiolitic rocks in Sulawesi. Ore Geology Reviews, 170, p.106140.
Ramadhan, A.R. et al., 2020. Lateritisasi pada kompleks melange Wailukum, Halmahera Timur. Bulletin of Geology, 4(1), pp.474–495.
Salam, R. et al., 2020. Terrain correction study in Karangsambung area. Jurnal Geofisika, 17(2), pp.9–15.
Salinding, J.C. et al., 2025. Kontrol morfologi pada profil vertikal endapan nikel laterit Pulau Kabaena. OPHIOLITE, 7(1), pp.31–42.
Sribudiyani, N.M. et al., 2003. The collision of the East Java Microplate and hydrocarbon implications. (tidak berseri jurnal jelas).
Suparka, M.E., 1988. Studi petrologi kompleks ofiolit Karangsambung. Disertasi. ITB.
Surono, 2013. Geologi Terintegrasi Sulawesi. Bandung: Badan Geologi.
Syafrizal, H. et al., 2009. Hubungan kemiringan lereng dengan distribusi ketebalan laterit di Halmahera Timur. JTM, 16(3).
Van Bemmelen, R.W., 1949. The Geology of Indonesia. The Hague: Government Printing Office.
Van Zuidam, R.A., 1985. Aerial photo-interpretation in terrain analysis. The Hague: Smits Publishers.
Downloads
Published
Issue
Section
License
Copyright (c) 2026 Buletin Sumber Daya Geologi
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Authors whose manuscripts are published in Buletin Sumber Daya Geologi agree to the following terms:
- Publication rights to all published materials are held by Buletin Sumber Daya Geologi with the knowledge of the authors, while the moral rights remain with the authors.
- All articles are published under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License (CC BY-NC-SA 4.0).
- Under this license, anyone may copy, redistribute, and adapt the work for non-commercial purposes, provided that appropriate credit is given to the authors and the journal, a link to the license is provided, any changes are indicated, and adapted works are distributed under the same license.
- Commercial use of the published material requires written permission from the publisher.
- Authors may deposit the published version of their article in institutional repositories, personal websites, or academic networks, provided that the original publication in Buletin Sumber Daya Geologi is acknowledged with its DOI.
