REGIONAL GEOLOGY OF DAWAI REGION AND SURROUNDINGS, EAST YAPEN DISTRICT, YAPEN ISLAND, PAPUA

• Main Author: RAHADIAN (NIM: 12008006); pembimbing: Bambang Priadi ; Chalid Idham Abdullah, REZA
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/19289
• Institution: Institut Teknologi Bandung

Research area is located on Dawai Area, East Yapen District, Yapen Island, Papua and geographically is on -53 zone, WGS 84 Datum, N9798000-9807000 E690000-700000. Total research area is 90 km2 (10 km x 9 km). <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> In this research area, there are 5 lithologic units identified, which arrange young to old are Mafic Igneous Rock Unit (part of Jobi Formation), Breccia Unit (Yapen Formation), Limestone Unit (Wurui Formation), Sandstone Unit (Kurudu Formation), and Alluvial and Beach Deposit, which deposited unconformably above those older units. <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> The oldest unit, Mafic Igneous Rock, was a part of oceanic crust and formed on Pre-Tertiary. On Eocene-Early Miocene, there was a high volcanism activity on Island Arc environment so that Breccia Unit was deposited unconformably above Mafic Igneous Rock Unit. On Early Miocene-Middle Miocene, a regression was occur and behind the Island Arc (the southern of Breccia Unit) was deposited a Limestone Unit on shallow marine environment, but on the northern of the Breccia Unit was deposited a shale deposit on deep marine environment which is not appear on the research area. On Late Miocene, there was an uplift so that Sandstone Unit was deposited on the shallow marine environment on the northern of the Breccia Unit. <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> In research area, there were two deformations happened, the first deformation was North-South stress direction on Middle Miocene-Late Miocene and the second was NE-SW stress direction (Jobi Fault /Sorong Fault) which developed on Early Pliocene to Recent time