GEOLOGI BAGIAN TIMUR SULAWESI HUBUNGANNYA TERHADAP SUMBERDAYA GEOLOGI UMS 30 MEI 2012
Surono
BADAN GEOLOGI, KESDM
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OUTLINE INTRODUCTION REGIONAL GEOLOGY EASTER SULAWESI CONTINENTAL TERRANES OPHIOLITE
GEOLOGICAL RESOURCES CONCLUSIONS
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EURASIA PLATE
PASIFIC PLATE
HINDIA- AUSTRALIA PLATE SULAWESI IS LOCATED IN A COLLISION ZONE BETWEEN 3 PLATES 3
INTRODUCTION
TOPOGRAPHY AND BATIMETRY OF SULAWESI AND SURROUNDING AREA
SRTM 30 Grid 1000 meter 4
MORPHOLOGICAL FEATURE OF THE NECK OF SULAWESI FROM IFSAR IMAGERY (Surono, 2010)
ANALISA MORFOLOGI LENGAN TENGGARA SULAWESI (Surono, 2010)
GRAVITY SULAWESI AND SURROUNDING AREA ON TOPOGRAPHY AND BATIMETRY MAPS
GEOLOGICAL AGENCY
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MAJOR STRUCTURES SULAWESI AND SURROUNDING AREA
(modified from Silver et al., 1983 dan Rehault et al., 1991 by Surono et al.,1997).
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PEMBAGIAN MENDALA GEOLOGI P. SULAWESI
(Sukamto, 1975 dimodifikasi Oleh Surono, 1996).
EASTERN SULAWESI
(SIMPLIFIED FROM GEOLOGICAL PUBLISHED BY GRDC)
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EASTERN SULAWESI
CONTINENTAL TERRANES IN EASTERN SULAWESI (Surono, 1996)
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EASTERN SULAWESI
TEKTONOSTRATIGRAPHY OF EASTERN SULAWESI 3 MAJOR GROUPS OF ROCKS: 1. CONTINENTAL TERRANE 2. OCEANIC TERRANE 3. SULAWESI MOLASSE
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SIMPLIFIED TECTONOSTRATIGRAPHY OF THE EASTERN SULAWESI
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PRE-COLLISION MELUHU FORMATION, (SE SULAWESI CONTINENTAL TERRANE) As deepening sediments (river deposits to be shallow water sediments upwards), Late Triassic Pmag analysis: sample taken from 3,5o S resulted 20o S (about 453,75 km away from present position) and rotated 25o clockwise. It is similar to northern margin of Australia. Moving rate is about 3,7 cm/year This basin was deepening (to be deep basin) until Cretaceous
PRE-COLLISION OPHIOLITE Ophiolite suite: mafic and ultra mafic rocks covered by deep sea sediments in places (CretaceousEocene) Pmag analysis: formed at 17o – 42o S (Mubroto, 1988), derived 1138,5 km from present position. Moving rate 3,7 – 9,3 cm/year
POST-COLLISION
Extension ----block faulting
Sulawesi Molasse: clastic-carbonate sediments, deposited in isolated basin - shallow marine Age: Early Miosen - Pliosen
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SUMBER DAYA GEOLOGI PADA KEPINGAN BENUA MINYAK DAN GAS BUMI Batuan induk (source rock): sedimen Mesozoikum dan Molasa Sulawesi (?) Batuan waduk (reservoir rock): sedimen Mesozoikum dan Molasa Sulawesi Batuan tudung (seal rock): sedimen Mesozoikum dan Molasa Sulawesi
MINERAL LOGAM EMAS DAN TEMBAGA Emas sebagai endapan sekunder dalam Molasa Sulawesi Mineralisasi pada batuan metamorf sebagai oroginic gold deposits
BOMBANA, 1999
KERUSAKAN LAHAN AKIBAT PENAMBANGAN TRADISIOLNIL TAK TERKENDALI
BATUAI
LOCATIONS OF PLACER GOLD DEPOSITS
Placer gold deposit within Quaternary sediments
KASIPUTIH
(Simplified from GRDC’s maps)
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LOCATION OF PLACER GOLD DEPOSITS IN THE SOUTHEAST ARM OF SULAWESI
Simandjuntak et al., 1992
Tmpb: Boepinang Formation Tmpe: Eemoiko Formation Tmls : Sandstone Member Langkowala Formation Tmlc : Conglomerate Member Langkowala Formation Km : Metalimestone Tmpm: Metamorphics Ku : Ophiolite Qa : Alluvium
LANDSAT IMAGERY OF LANGKOWALA AREA
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Nickel and iron locations in Southeast Sulawesi 22
HYDROCARBON POTENCIAL IN SULAWESI (Jablonski et al., 2007 in Setyana, 2011) 23
SUMBER DAYA GEOLOGI PADA KEPINGAN SAMUDRA NIKEL Sebagai hasil pelpukan dan pengakayan batuan ofiolit, yang tersebar di bagian timur Sulawesi dan beberapa pulau di sekitarnya. KROM Sebagai hasil pelapukan ofiolit yang diendapkan kembali pada endapan Kuarter PLATINA Umumnya ditemukan sebagai endapan sekunder pada sedimen halus Molasa Sulawesi dan sedimen Kuarter
KEBENCANAAN Bagian timur P. Sulawesi dibentuk oleh batuan ofiolit dan kepingan benua yang aktif bertabrakan Sesar aktif regional di antaranya: Sesar Lawanopo, Sesar Konaweha, dan Sesar Kolaka. Kegempaan, tsunami, gerakan tanah & banjir sangat mungkin terjadi di sepanjang sesar aktif dan daerah sekitarnya.
STRUKTUR UTAMA DAN BATIMETRI SESAR AKTIF
(dimodifikasi dari Silver drr., 1983 dan Rehault drr., 1991 oleh Surono drr., 1997).
DAMPAK SESAR AKTIF • • • •
CONCLUSION Eastern Sulawesi composed by continental and oceanic terranes covered by Sulawesi Molasse Continental terrane collided with oceanic terrane during latest Oligocene – Middle Miocene times Primary metallic mineral (gold) could be found within continental terrane Nickel in ophiolite suite Hydrocarbon potential in continental terrane
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UN SHINE AT THE LUWUK BEACH
MATUR NUWUN
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