EKSPLORASI GEOLOGI BIJIH BESI BERDASARKAN DATA GEOLISTRIK INDUKSI POLARISASI DAERAH NGOLONIO NUSA TENGGARA TIMUR

Authors

  • Adi Candra Jurusan Teknik Geologi Universitas Jendral Soedirman (UNSOED)
  • Fadlin Fadlin Jurusan Teknik Geologi Universitas Jendral Soedirman (UNSOED)
  • Juan Pandu GNR Jurusan Teknik Geofisika Institut Teknologi Sepuluh November (ITS)

Abstract

ABSTRACT

Iron oxides are widespread in nature such as hematite (Fe2O3), magnetite (Fe3O4), ilmenite (TiO2 FeO), Geothite (FeO OH), limonite (FeO OH H2O), siderite (Fe2CO3), and other types. Extraction of iron oxides are used in industrial world of steel/iron which was increased in day to day. Geoelectric survey is one of the methods for studying subsurface conditions which recoreded by electrical properties of rock beneath the earth's surface that using geoelectric method modified induced polarization configuration that was conducted at Ngolonio Area, Nagakeo Regency, East Nusa Tenggara. Magnitude of induced polarization results was formed of a cross-2D and 3D model that pointed out information of iron ore distribution in the western and eastern part. Parameter test of iron ore in research area was resulted 100 to 500 ohm m for resistivity and >10 ms for the induced polarization which used for calcution of hypothetical resources. The number of resources is 14,568,866 m3 of 1,144,275 m2 area were observed to a depth of 113 m or 86.202 million m3 volume observed in western meanwhile in eastern area of 5,040,542 m3 of 366 750 m2 area were observed to a depth of 113 or 27.6285 million m3 by using a density rock 4 g/cm3. Lithological interpretation of magnitude parameters on resistivity and induced polarization was pointed out that geological conditions made sense and it could be used for consideration of iron ore exploration in future.

 

keyword : iron ore, geoelectricity, induced polarization, resources

 

ABSTRAK

Besi pada umumnya berbentuk oksida besi seperti hematit (Fe2O3), magnetit (Fe3O4), ilmenit (FeO TiO2), Geotit (FeOOH), Limonit (FeO OH H2O), Siderit (Fe2CO3), dan jenis batuan besi lainnya. Besi digunakan dalam dunia industri baja/besi dimana kebutuhannya semakin setiap tahun. Geolistrik merupakan salah satu metoda penyelidikan kondisi bawah permukaan dengan mempelajari sifat listrik pada batuan di bawah permukaan bumi. Penelitian ini dilakukan di Daerah Ngolonio dan Sekitarnya, Kabupaten Nagakeo, Nusa Tenggara Timur dengan menggunakan metoda geolistrik konfigurasi induksi polarisasi. Hasil pengukuran resistiviti induksi polarisasi berupa penampang 2D dan blok model 3D yang memberikan informasi mengenai sebaran bijih besi pada bagian barat dan timur. Hasil uji parameter untuk bijih besi 100 sampai 500 ohm m untuk resistivitas dan > 10 ms untuk induksi polarisasi. Besarnya sumberdaya untuk daerah bagian barat sebesar 14.568.866 m3 dari 1.144.275 m2 luas area yang diamati hingga kedalaman 113 atau 86.202.000 m3 volume area yang diamati. Sedangkan untuk bagian daerah timur sebesar 5.040.542 m3 dari 366.750 m2 luas area yang diamati hingga kedalaman 113 atau 27.628.500 m3. Interpretasi litologi hasil pengukuran parameter menunjukkan kecocokan dengan kondisi geologi secara umum daerah penelitian dan dapat digunakan untuk bahan pertimbangan tahapan eksplorasi bijih besi lebih lanjut.

 

kata kunci : bijih besi, geolistrik, induksi polarisasi, sumberdaya 

References

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Published

2017-01-18

Issue

Vol. 1 No. 2 (2015)

Section

Articles