Integrated Exploration Method to Determine Cu Prospect in Seweden District, Blitar, East Java

Seweden district is located in the mountain range of Southern Java shows the indication of polymetallic mineralization. The area of study is characterized by the crystalline limestone, clay stone intercalation (Campurdarat Formation), and andesitic-basaltic-lava, porphyry lattice, rhyolite, dacite (Mandalika Formation). This area is chosen as the presence of copper mineralization, strong alteration, and magmatic activities that exposed because of the human activities.Aerial photo shows that the lineaments structure dominated in the area of study. Petrography and mineragraphy analysis shows the alteration mineral e.g. quartz (SiO2), dickite (Al2Si2O5(OH)4), pyrite (FeS2), sericite KAl2[Si3AlO10](OH,F), plagioclase (NaAlSi3O8) and cryptocrystalline mineral. Silicified quartz is clearly identified, where the fragment consist of quartz and sericite mineral.Geochemical study in this area is taken by analyzing samples from stream sediment, Bulk Leach Extractable Gold (BLEG), panned concentrate and rock chip samples. Gold grades varies from 4 ppb (stream sediment sample), 110 ppb (rock chip sample), 56 ppb (panned concentrate sample), and 293 ppb (BLEG sample). Copper grades varies from 1760 oom (rock chip sample), 66 ppm (panned concentrate sample). It is predicted that hydrothermal activities in Seweden district controls the mineralization.