IDENTIFICATION OF THE EXISTENCE OF PORFIRI GOLD DEPOSIT TYPE AROUND LOW SULFIDATION GOLD DEPOSIT TYPE USING SURFACE GEOCHEMISTRY, GEOLOGICAL AND GEOPHYSICAL ANALYSIS IN THE TRADITIONAL MINING AREA, PANINGKABAN VILLAGE, BANYUMAS, CENTRAL JAVA

• Main Author: SATRIA PAMUNGKAS (NIM : 22116301), TANGGUH
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/31219
• Institution: Institut Teknologi Bandung

This research has been carried out in the traditional mining area of Paningkaban village, Gumelar sub-district, Banyumas district, to prove the presence of porfiri-type deposits that indicated to have a relation from traditional mining sites of low sulfidation epithermal deposits ranging from 500-800 from target prospect indications. Based on geophysical data, another deposit type is indicated which has features such as Porfiri type deposits. This porfiri-type deposit feature was initially deduced from the Halo magnetic anomali feature which indicates potassic-type alteration in the core, surrounded by other alterations that are magnetic destructive. The results were then confirmed from the Gravity data analysis which showed the presence of intrusion with a depth of ± 86 meters obtained from Audiomagnetotellurik data. <br /> <br /> From the results of topographic analysis and community interviews, the target of the indicated porfiri prospect is a 220 meter of hill called Igir Cilerang. The prospect target is part of the Cihonje syncline which is a pre-mineralized structure of the vein system, with the lithology revealed in the foothills as diatrema breccias. Mineralization analysis was carried out with the help of X-Ray Diffraction (XRD) and produced a range of alterations in the southeast-northwest direction as argillic-philic-potasic-argillic-propylitic type. The prospect target is part of the potasic alteration with the main minerals as magnetite and k-feldspar. Geochemical analysis of surface soil was carried out with the help of X-Ray Flouroscence (XRF) and showed some elements enrichment including K (0-7%), Ca (2-20%), Fe (25-43%), and Al ( 12-17%), but Si (25-38%) has decrease. The results are comprehensively compared to the types of porphyry related to low sulphidation deposit models, and it was concluded that the target prospects in the study area were Quartz Sulphide Au vein/breccia type deposits.