Electronic Theses and Dissertation

Penelitian tentang analisis variasi suseptibilitas magnetik bawah permukaan sebagai identifikasi sebaran mineral telah dilakukan pada kawasan siron blang, kecamatan kuta cot glie, kabupaten aceh besar. lokasi penelitian berada pada formasi geologi komplek indrapuri yang terdiri dari batuan ultramafik serpentinit. penelitian ini bertujuan untuk mendapatkan variasi nilai intensitas medan magnetik dan dapat mengidentifikasi sebaran mineral berdasarkan variasi nilai suseptibilitas batuan. sebaran mineral dapat diidentifikasi dengan menggunakan metode magnetik berdasarkan nilai anomali magnetik yang terukur di bawah permukaan. data intensitas magnetik diukur dengan menggunakan alat magnetometer proton precession magnetometer (ppm) gsm-19t gem system. jumlah titik pengukuran sebanyak 123 titik yang diakuisisi secara grid. data intensitas magnetik yang diperoleh dari pengukuran diolah menggunakan software oasis montaj 8.3.3 dan surfer 15. untuk mendapatkan nilai anomali magnetik, data intensitas magnetik terukur dikoreksi terlebih dahulu dengan koreksi harian dan igrf dan selanjutnya direduksi ke ekuator untuk menghilangkan efek dipol. kemudian dilakukan pemisahan anomali regional dan residual. kontur anomali residual yang dihasilkan, selanjutnya dilakukan pemodelan 2d. berdasarkan hasil interpretasi kuantitatif didapatkan pemodelan 2d dengan 3 lapisan struktur bawah permukaan yaitu top soil, endapan mineral hematit dengan nilai suseptibilitas 25 x 10-3 yang sebarannya berada pada daerah bagian barat, utara, selatan, timur dan hampir berada seluruh daerah penelitian. batuan serpentinit dengan nilai suseptibilitas 7 x 10-3 yang sebarannya berada pada daerah bagian timur dan selatan lokasi penelitian.

Research on the analysis of subsurface magnetic susceptibility variations for mineral distribution identification has been conducted in the Siron Blang area, Kuta Cot Glie Subdistrict, Aceh Besar Regency. The research location is within the geological formation of the Indrapuri Complex, which consists of ultramafic serpentinite rocks. The objective of this study is to obtain variations in magnetic field intensity values and to identify mineral distributions based on the variation in rock susceptibility values. Mineral distributions can be identified using magnetic methods based on measured magnetic anomalies beneath the surface. Magnetic intensity data were measured using a Proton Precession Magnetometer (PPM) GSM-19T GEM System. A total of 123 measurement points were acquired in a grid pattern. The magnetic intensity data obtained from measurements were processed using Oasis Montaj 8.3.3 and Surfer 15 software To obtain magnetic anomaly values, the measured magnetic intensity data were first corrected for daily variations and the International Geomagnetic Reference Field (IGRF). Subsequently, the data were reduced to the equator to eliminate dipole effects. The regional and residual anomalies were then separated. Contours of the resulting residual anomalies were used for 2D modeling. Based on the quantitative interpretation results, a 2D model with three subsurface layers was obtained: topsoil, hematite mineral deposits with a susceptibility value of 25 x 10-3 , distributed in the western, northern, southern, eastern, and almost the entire research area. Serpentinite rocks with a susceptibility value of 7 x 10-3 were distributed in the eastern and southern parts of the research location.