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"Batugamping Formasi Rajamandala yang berumur Oligo-Miosen tersingkap di lintasan Sanghyang, Kabupaten Bandung Barat. Pengukuran stratigrafi rinci telah dilakukan di lintasan sepanjang 2,5 km, untuk memperkirakan perkembangan lingkungan pengendapan batuan. Formasi Rajamandala mempunyai ketebalan terukur mencapai 180 m, terdiri atas batugamping boundstone, rudstone, grainstone, packstone, wackestone, dan terendapkan dalam keadaan cekungan genang laut. Lingkungan pengendapan Formasi Rajamandala dimulai endapan batugamping pada fasies terumbu depan hingga inti terumbu. Lingkungan pengendapan ini berkembang menjadi perulangan endapan batugamping pada fasies sayap terumbu hingga terumbu depan dengan beberapa sisipan bentukan inti terumbu. Karena terpengaruh oleh genang laut, lingkungan pengendapan batuan bergeser dan diakhiri oleh endapan batugamping dari fasies tepi lerengan dan dangkalan paparan karbonat. "

"Nenering Formation is essentially made up of semi-consolidated sediments, which are divided into basal conglomerate beds, conglomeratic sandstone, cross-bedded sandstone, and siltstone to muddy layers facies. It is overlie unconformable to the Berapit Formation, but conformable to the Kroh and Grik Formations. The stratigraphy of Nenering Formation is a fining upwards sequence where the thickness of conglomerate beds become thinner upwards and become thicker for conglomeratic sandstone. The thickness varies from 0.5 m to tenths of meters. The more sandy in the upper portion (cross-bedded sandstone) overlie with thin siltstone and mudstone facies. The clast and grain composition suggested that the material making up the sedimentary sequence were derived predominantly from the erosion of granitoid rocks and sedimentary and metamorphic rocks constitute a minor provenance. Imbrications and the trend sizes of clasts indicate that the palaeo-current flow toward northeast. Cross bedding that was found in conglomerate and sandstone indicates the main channel depositional environment. The sequence stratigraphy of this area match with the Saskatchewan fluvial braided channel model."

"This comprehensive textbook presents an overview of petroleum geoscience for geologists active in the petroleum industry, while also offering a useful guide for students interested in environmental geology, engineering geology and other aspects of sedimentary geology. In this second edition, new chapters have been added and others expanded, covering geophysical methods in general and electromagnetic exploration methods in particular, as well as reservoir modeling and production, unconventional resources and practical petroleum exploration."

"Gunung Endut merupakan salah satu gunung yang berada pada Kabupaten Lebak, Provinsi Banten. Daerah Gunung Endut didominasi oleh batuan vulkanik kuarter produk Gunung Endut, Sedimen tersier dari Formasi Bojongmanik dan batuan intrusi tersier. Formasi Bojongmanik tersusun atas batupasir tufan, batulempung, konglomerat, dan sisipan batubara muda. Sisipan batubara pada Formasi Bojongmanik memiliki ketebalan sekitar 2cm – 2m. Karakteristik batubara Formasi Bojongmanik pada daerah penelitian masih belum diketahui. Oleh karena itu, hal ini penting dilakukan untuk mengkarakterisasi batubara agar dapat mengetahui kualitas dari batubara tersebut.Penelitian ini bertujuan untuk mengkarakterisasi batubara dari Formasi Bojongmanik di daerah Gunung Endut menggunakan analisis batubara maseral, analisis proksimat, dan analisis ultimat. Lima sampel batubara dari darah penelitian telah dikumpulkan dan dianalisis. Analisis petrografi menunjukkan bahwa empat dari lima sampel menunjukkan bahwa lingkungan pengendapan dari batubara tersebut merupakan rawa yang masih dipengaruhi oleh pasang surut air laut, sehingga kualitas batubara buruk. Tetapi ada satu sampel batubara yang memiliki kualitas cukup baik namun tetap memiliki kandungan abu yang cukup tinggi, yaitu sampel batubara yang berada cukup dekat dengan intrusi batuan beku. Selain itu, hasil analisis proksimat dan ultimat menunjukkan bahwa hampir seluruh sampel memiliki kandungan abu yang tinggi dan mineral pirit yang cukup banyak sehingga menyebabkan nilai kalori batubara pada daerah ini buruk. Dari hasil tersebut, dapat disimpulkan bahwa kualitas batubara pada daerah penelitian ini memiliki kualitas yang buruk namun terdapat satu sampel batubara yang memiliki kualitas yang cukup baik.

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Gunung Endut is a mountain positioned in Lebak Regency, Banten Province. The region is consisted of Quarternary volcanic rocks of Gunung Endut and Tertiary Bojongmanik Formation. The Bojongmanik Formation consisted of tuf f aceous sandstone, mudstone, conglomerate, and intercalation of young coal, with thickness from 2cm to 2 m. The coal characteristic s of Bojongmanik formation in study area are still not well known. Therefore, its important to characterise the coal in order to understand its quality.

This study attempted to characterise the coal from the Bojongmanik Formation in the Endut Mountain Area using coal maceral analysis, proximate analysis, and ultimate analysis. Five coal samples from the study area have been collected and analysed. Petrographic analysis indicate that four of the five samples has swamp depositional environment that was still affected by tidal sea water, causing the poor coal quality. However, there is one sample of coal that has a fairly good quality althoughstill has a fairly high ash content, which is a coal sample that is quite close to igneous intrusion. In addition, the results of the proximate and ultimate analysis showed that almost all samples had high ash content and pyrite minerals which caused the calorific value of coal in this area is poor. From these results, it can be concluded that the quality of coal in this study area is poor but there is one sample of coal still has a fairly good quality."

"Formasi Baturaja merupakan reservoir karbonat yang aktif berproduksi di Cekungan Sunda. Formasi Baturaja memiliki sifat batuan yang kompleks dan heterogen dikarenakan batugamping memiliki fasies pengendapan yang bervariasi dan pengaruh kontrol diagenesis terhadap petrofisika batuan. Oleh karena itu, analisis hubungan antara fasies pengendapan dan analisis petrofisika dibutuhkan untuk mengevaluasi produktivitas cekungan dalam menyimpan dan mengalirkan hidrokarbon. Studi fasies pengendapan dan petrofisika batuan dapat dianalisis melalui data wireline log yang dikombinasikan dengan data batuan inti, dan data pendukung lain seperti Drill Stem Test. Berdasarkan data tersebut, fasies pengendapan dan sifat petrofisika batuan di wilayah penelitian dapat dianalisis berdasarkan pola elektrofasies, rock type Hydraulic Flow Unit, dan deskripsi batuan inti. Analisis petrofisika dilakukan melalui perhitungan log sumur, meliputi Volume Shale (Vsh), porositas efektif (PHIE), dan saturasi air (Sw) dengan tujuan untuk mengevaluasi ketebalan zona hidrokarbon. Pola elektrofasies yang ditemukan di wilayah penelitian mencakup pola Cylindrical dengan asosiasi fasies Mudstone-Packstone dan dominasi rock type HFU 4-7 serta pola Bell dengan asosiasi fasies Wackestone-Grainstone dan dominasi rock type HFU 1-4. Karakteristik batuan yang tersebar mencerminkan lingkungan pengendapan Inner Lagoon hingga Outer Lagoon. Parameter petrofisika wilayah penelitian memiliki interval nilai rata-rata, yaitu Volume Shale (Vsh) 17,1%-43,9%; Porositas Efektif (PHIE) 13,8%-19%; dan Saturasi air (Sw) 65,9%-94,6%. Berdasarkan nilai cut-off yang ditentukan, nilai net pay kumulatif dari kelima sumur penelitian adalah 361,5’ MD dengan pay zone paling tebal sekitar 130,5’ MD di sumur Q-1. Sumur paling produktif dalam menyimpan hidrokarbon terletak pada sumur Q-3 (54%) dan Q-1 (44,5%).

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The Baturaja Formation is an active carbonate reservoir in the Sunda Basin. The Baturaja Formation exhibits complex and heterogeneous rock properties due to its varied deposition facies and the influence of diagenesis on rock petrophysics. Therefore, an analysis of the relationship between sedimentation facies and petrophysical analysis is needed to evaluate the productivity of the basin in storing and draining hydrocarbons. Studies of sedimentation facies and rock petrophysics can be analyzed through data from Wireline Logs combined with core rock data, and other supporting data, such as Drill Stem Tests. Based on these data, the deposition facies and petrophysical properties of the rocks in the study area can be analyzed based on the pattern of electrophacies, rock type Hydraulic Flow Unit, and a description of the core rock. Petrophysical analysis is carried out through the calculation of well logs, including Volume Shale (Vsh), effective porosity (PHIE), and water saturation (Sw) to evaluate the thickness of the hydrocarbon zone. The patterns of electrofacies found in the study area include the Cylindrical with the facies association Mudstone-Packstone and dominance Rock Type HFU 4-7, and patterns Bell with the facies association Wackestone-Grainstone and dominance Rock Type HFU 1-4. The characteristics of the scattered rocks reflect the deposition environment Inner Lagoon to Outer Lagoon. The petrophysical parameters of the research area have an average value interval: Shale Volume (Vsh) 17.1%-43.9%; Effective Porosity (PHIE) 13.8%-19%; and Water saturation (Sw) 65.9%-94.6%. By value Cut-off specified, the value net pay cumulative of the five research wells is 361.5' MD, with the pay zone thickest about 130.5' MD in well Q-1. The most productive wells for storing hydrocarbons are located in the Q-3 (54%) and Q-1 (44.5%) wells."

"Lokasi penelitian berada pada Formasi Cinambo wilayah Daerah Jatinunggal, Sumedang Jawa Barat. Pada lokasi ini, tersingkap dengan baik beberapa singkapan sepanjang Anak Sungai Ci Jaweu pada Desa Cibuyung dan Desa Cimanintin yang terbagi menjadi dua lintasan. Litologi penyusunnya adalah feldspathic wacke, allochemic mudstone, foraminiferal-packstone, foraminiferal-wackestone, dan batulanau. Porositas batuannya memiliki rentang poor – excellent (>25%). Berdasarkan pengamatan lapangan, pengukuran stratigrafi, dan analisis petrografi, lokasi penelitian tersusun atas Kelompok Fasies B, C, D, dan G yang terbagi lagi menjadi 7 anggota litofasies. Kelompok-kelompok fasies yang saling berasosiasi kemudian dikelompokan menjadi 3 asosiasi fasies yaitu Sandy-silt lobe distal, distal levee, dan distal silt-mud lobe. Analisis mikrofosil yang dilakukan, menunjukan lapisan pada lokasi penelitian memiliki umur Miosen Tengah/Miosen Akhir dan terendapkan pada lingkungan upper-lower bathyal. FormasiCinambo yang tersingkap pada daerah ini diinterpretasikan berada pada lingkungan kipas laut dalam bagian tengah (middle fan).

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The research location is in the Cinambo Formation in the Jatinunggal Region, Sumedang, West Java. At this location, several outcrops along the Ci Jaweu River in Cibuyung Village and Cimanintin Village are well exposed and are divided into two tracks. Its constituent lithologies are feldspathic wacke, allochemic mudstone, foraminiferal-packstone, foraminiferal-wackestone, and siltstone. The rock porosity ranges from poor to excellent (>25%). Based on field observations, stratigraphic measurements, and petrographic analysis, the study site is composed of Facies B, C, D, and G which are further divided into 7 lithofacies. Facies groups that are associated with each other are then grouped into 3 facies associations namely distal Sandy-silt lobe, distal levee, and distal silt-mud lobe. The microfossil analysis performed showed that the layers at the study site are Middle Miocene/Lower Miocene and were deposited in an upper-lower bathyal environment. The Cinambo Formation exposed in this area is interpreted to be in the middle fan environment."