Identifikasi Karakteristik Zona Prospek Timah Primer Berdasarkan Pemetaan Geologi Permukaan dan Analisis Geokimia Daerah Kelapakampit dan Sekitarnya, Kabupaten Belitung Timur, Provinsi Bangka Belitung

Abstract

Kepulauan Bangka Belitung memiliki potensi timah yang besar baik timah primer dan timah sekunder. Akan tetapi timah primer belum dimanfaatkan secara optimal dibandingkan timah sekunder sehingga perlu dilakukan penelitian secara lebih lanjut. Penelitian ini dilakukan di Kelapakampit dan sekitarnya, Kabupaten Belitung Timur. Tujuan dari penelitian ini yaitu. mengetahui kondisi geologi dan zona prospek endapan timah primer di daerah penelitian. Metode penelitian yang dilakukan yaitu pemetaan geologi permukaan, analisis geomorfologi, struktur geologi, petrologi, petrografi, mineragrafi, X-Ray Difraction (XRD), dan X-Ray Fluorescence (XRF). Berdasarkan hasil analisis diketahui geomorfologi daerah penelitian terdiri dari berbukit bergelombang-berbukit terjal struktural dan bergelombang miring-landai struktural. Daerah penelitian terdiri dari 2 satuan litologi yaitu metabatupasir dan batupasir. Struktur yang berkembang di daerah penelitian berupa kekar tarik, kekar gerus, kelurusan, dan indikasi sesar. Tipe alterasi hidrotermal di daerah penelitian termasuk kedalam eksogreisen dan argilisisasi. Mineralisasi yang berkembang di daerah penelitian termasuk dalam tipe endapan urat kuarsa-kasiterit dan sulfida-kasiterit. Mineralisasi timah dicirikan dengan hadirnya mineral kasiterit yang berasosiasi dengan beberapa mineral sulfida. Berdasarkan analisis geokimia XRF, nilai Sn pada sampel batuan menunjukkan rentang dari 115,5-727,7 ppm dan sampel streams sediment menunjukkan rentang 51 130.800 ppm. Zona prospek timah primer terdapat pada bagian tengah dan barat laut daerah penelitian. Ditemukan anomali Pb dengan rentang 5.080 - 173.590 ppm dan Zn dengan rentang
1.680 - 2.040 ppm.

Kata Kunci: Belitung, Timah Primer, Mineralisasi, Zona
Prospek

Abstract

The Bangka Belitung Islands have great tin potential,
both primary and secondary tin. However, primary tin has
not been utilized optimally compared to secondary tin, so
further research is needed. This research was conducted in
Kelapakampit and its surroundings, East Belitung Regency.
The purpose of this study is to determine the geological
conditions and the prospective zones of primary tin deposits
in the study area. The research methods applied include surface
geological mapping, geomorphological analysis, geological
structure studies, petrology, petrography, mineragraphy, X-Ray
Diffraction (XRD), and X-Ray Fluorescence (XRF). Based on
the analysis results, it is known that the geomorphology of
the study area consists of rolling hills to steep structural hills
and gently sloping structural undulating areas. The study
area consists of 2 lithology units, namely metasandstone and
sandstone. The structures developed in the study area include
tension joints, shear joints, lineaments, and indications of
faults. The types of hydrothermal alteration in the study area
include exogreisen and argillization. Mineralization developed
in the study area belongs to the type of quartz-cassiterite vein
deposits and cassiterite-sulfide deposits. Tin mineralization is
characterized by the presence of cassiterite mineral associated
with several sulfide minerals. Based on XRF geochemical
analysis, Sn values in rock samples range from 115.5–727.7
ppm, and stream sediment samples range from 51–130,800
ppm. The primary tin prospect zone is located in the central
and northwest parts of the study area. An anomaly of Pb was
found with a range of 5.080 - 173.590 ppm and Zn with a range
of 1.680 - 2.040 ppm.

Keywords: Belitung, Primary Tin, Mineralization, Prospect
Zone