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"Penelitian ini berlokasi di daerah Kalan, Kabupaten Melawi, Kalimantan Barat. Batuan Metamorf Pinoh merupakan litologi dominan yang terbentuk pada Pegunungan Schwaner. Batuan Metamorf Pinoh merupakan formasi batuan yang berumur tua, yakni berumur Trias. Batuan Metamorf di daerah Kalan memiliki kajian menarik untuk dilakukan penelitian, karena didapatkan mineralisasi unsur radioaktif. Terbentuknya mineralisasi unsur radioaktif berkaitan dengan protolith dan fasies metamorfime (proses suhu dan tekanan). Untuk mengkaji penelitian ini, digunakan beberapa metode penelitian. Metode penelitian yang digunakan adalah pengukuran radiometrik, analisis petrologi, analisis geokimia, dan analisis petrografi. Metode-metode tersebut di korelasikan sehingga mendapatkan kesimpulan protolith dan fasies metamorfismenya. Daerah Kalan ditemukan protolith berupa batuan pelitik dan batuan kuarsa-feldspatik. Fasies metamorfisme yang terjadi adalah fasies sekis hijau yang dicirikan dengan ditemukan mineral klorit, aktinolit, muskovit, biotit, kuarsa, hingga garnet.

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This study is located in the Kalan area, Melawi Regency, West Kalimantan. Pinoh Metamorphic Rocks are the dominant lithology formed in the Schwaner Mountains. Pinoh Metamorphic Rock is an old rock formation, which is Triassic in age. Metamorphic rocks in the Kalan area have interesting studies to conduct research, because radioactive element mineralisation was obtained. The formation of radioactive element mineralisation is related to protoliths and metamorphism facies (temperature and pressure processes). To study this research, several research methods were used. The research methods used are radiometric measurements, petrological analysis, geochemical analysis, and petrographic analysis. These methods are correlated to get the conclusion of protoliths and metamorphism facies. The Kalan area found protoliths in the form of pelitic rocks and quartz-feldspathic rocks. The metamorphism facies that occurs is the green schist facies characterised by the discovery of chlorite, actinolite, muscovite, biotite, quartz, and garnet minerals."

"Kawasan Gunung Endut merupakan kawasan yang tersusun atas batuan beku plutonik Tersier dan batuan beku vulkanik Kuarter yang diduga merupakan hasil proses subduksi tektonik yang terjadi di selatan Jawa. Penelitian ini bertujuan untuk mengetahui jenis batuan beku dan menginterpretasikan jenis magma, evolusi magma, dan tatanan tektonik yang membentuk batuan beku di daerah penelitian. Metode yang digunakan dalam penelitian ini adalah analisis petrologi, analisis petrografi, dan analisis geokimia batuan beku menggunakan XRF. Batuan beku Gunung Endut terdiri dari beberapa satuan batuan beku yaitu batuan beku lava basaltik/andesitik, batuan beku intrusi tanggul basaltik/andesitik, dan batuan beku intrusi stok basaltik/andesitik. Analisis petrografi batuan beku Gunung Endut menunjukkan bahwa batuan lava beku terdiri dari porfiri andesit, sedangkan batuan beku intrusi terdiri dari porfiri diorit dan porfiri dasit. Tekstur mikro dari plagioklas yang terdapat pada setiap sampel menunjukkan bahwa batuan beku Gunung Endut telah mengalami pencampuran magma dengan magma primitif. Berdasarkan diagram TAS, batuan lava beku tersusun atas andesit, dasit, traki-andesit, andesit basaltik, trakhdasit trakit, dan basaltik trachy-andesit. Batuan beku intrusi terdiri dari batuan beku andesit, trachy-andesite, basaltic andesite, dan trachy trachydacite. Deret magma pembentuk batuan beku Gunung Endut merupakan gugus magma kalk-alkali yang menopang lingkungan tektonik pembentuk batuan beku Gunung Endut yaitu batas kontinen aktif.

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The Mount Endut area is an area composed of Tertiary plutonic igneous rocks and Quaternary volcanic igneous rocks which are thought to be the result of a tectonic subduction process that occurred in southern Java. This study aims to determine the types of igneous rocks and interpret the types of magma, magma evolution, and tectonic arrangements that form igneous rocks in the study area. The methods used in this research are petrological analysis, petrographic analysis, and geochemical analysis of igneous rocks using XRF. Mount Endut igneous rock consists of several igneous rock units, namely basaltic/andesitic lava igneous rock, basaltic/andesitic embankment intrusion igneous rock, and basaltic/andesitic stock intrusion igneous rock. Petrographic analysis of the Gunung Endut igneous rock shows that the igneous lava rock consists of andesite porphyry, while the intrusive igneous rock consists of diorite porphyry and dacite porphyry. The micro texture of the plagioclase contained in each sample shows that the igneous rock of Mount Endut has undergone magma mixing with primitive magma. Based on the TAS diagram, igneous lava rock is composed of andesite, dacite, trachy-andesite, basaltic andesite, trachyde-tracheal and basaltic trachy-andesite. Intrusion igneous rock consists of igneous andesite, trachy-andesite, basaltic andesite, and trachy trachydacite. The magma series that forms the igneous rocks of Mount Endut is a calc-alkaline magma group that supports the tectonic environment that forms the igneous rocks of Mount Endut, which is the active continent boundary."

"Method in calculating thickness changes of sedimentary layers caused by compaction (decompaction) has been developed to reconstruct geohistory of the basin accurately. Decompaction method which is used in this research proposed by Angevine et al (1987) and several input from other researchers such as Van Hinte (1978) and Perrier and Quiblier (1974) are also applied.Thickness changes calculation of sedimentary layers caused by compaction (dccompaction) is based on the reduction of porosity with depth and assuming volume of grain to be constant. Parameters which are needed in this calculation include trend of porosity reduction, initial thickness, ages, depth and compaction factor of sedimentary layers.Porosity reduction during burial is unique and different for lithology types with different depositional environment or facies. Grouping of layers based on depositional environment or facies is necessary to produce an accurate porosity trend of the layers.Case study of Q-1 Well, which is drilled in Kampar Block, Central Surnatera Area produced seven groups with different depositional environment or facies. Each group has different porosity trend for each lithology type (shale and sandstone or limestone).Geohistory analysis can be constructed accurately if thickness changes caused by compaction are known. This analysis is used to potray vertical movement of a stratigraphic horison as an indicator of subsidence and uplift history in the basin since the horison was deposited."