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"Formasi jatiluhur merupakan salah satu formasi yang terletak di utara cekungan Bogor dengan persebaran lateral yang cukup luas dan diperkirakan diendapkan pada Miosen tengah hingga Miosen akhir. Formasi Jatiluhur merupakan formasi yang disusun oleh litologi campuran sedimen klastik berupa batupasir, batulanau, batulempung dan batugamping. Daerah penelitian berada di sepanjang Sungai Cipamingkis yang terletak di Desa Sukamakmur, Kecamatan Jonggol - Bogor. Penelitian ini bertujuan untuk menentukan karakteristik litologi yang ada pada daerah penelitian yang nantinya akan digunakan dalam penentuan kelompok mikrofasies yang ada pada daerah penelitian. Terdapat tiga metodologi digunakan oleh penulis dalam penelitian ini yaitu pengukuran penampang stratigrafi, analisis petrografi dan analisis mikropaleontologi. Panjang lintasan yang didapatkan pada pengukuran penampang stratigrafi adalah sekitar 280 meter dengan total data sampel yang didapatkan adalah sebanyak 27 sampel. Dari 27 sampel yang didapatkan dipilih sebanyak 14 sampel untuk dilakukan analisis petrografi dan 5 sampel untuk dilakukan analisis mikropaleontologi. Secara umum ukuran butir penyusun batuan pada daerah penelitian didominasi oleh pasir halus hingga silt dan keseluruhan sampel memiliki kandungan karbonat dengan struktur bioturbasi yang cukup dominan. Dari hasil analisis sayatan tipis, dihasilkan tiga Standard Microfacies (SMF) pada daerah penelitian yaitu SMF-18, SMF-23, dan SMF-24. Ketiga mikrofasies tersebut, penulis namakan SMF-18 sebagai Fasies C, SMF-23 sebagai Fasies B, dan SMF-24 sebagai Fasies A. Berdasarkan semua data yang telah terkumpul, dihasilkan tiga event atau kejadian geologi yang terjadi pada daerah penelitian dengan lingkungan pengendapan berada pada brackish-clastic dominated, brackish-marine dominated dan platform interior restricted.......Jatiluhur Formation is one of the unique formations found in the North of Bogor Basin which spread widely and deposited in the Middle Miocene to Upper Miocene. Jatiluhur Formation consists of mixed siliciclastics with carbonate such as sandstone, siltstone, claystone, and limestone. The research area is along the Cipamingkis River which is located in Sukamakmur Village, Jonggol District - Bogor. This study aims to determine the lithological characteristics present in the study area which will later be used in determining the microfacies groups present in the study area. There are three methodologies used by the authors in this study, namely stratigraphic cross-sectional measurements, petrographic analysis and micropaleontological analysis. The path length obtained from the stratigraphic cross-section measurement is about 280 meters with a total sample data obtained of 27 samples. Of the 27 samples obtained, 14 samples were selected for petrographic analysis and 5 samples for micropaleontological analysis. In general, the grain size of the rock constituents in the study area was dominated by fine sand to silt and all samples contained carbonate with a fairly dominant bioturbation structure. From the results of thin section analysis, three Standard Microfacies (SMF) were produced in the study area, namely SMF-18, SMF-23, and SMF-24. The authors call the three microfacies SMF-18 as Facies C, SMF-23 as Facies B, and SMF-24 as Facies A. Based on all the data that has been collected, three geological events have occurred in the study area with depositional environments on brackish-clastic dominated, brackish-marine dominated and restricted interior platforms."

"A sedimentology survey was conducted during “Pelayaran Kebangsaan� research activities with a marine vessel of "Baruna Jaya VIII" in Karimun Java Sea. The objectives of the research were to determine the characteristics of marine water and its sediment, which are important control for coral reef growth in the study area. The survey acquired samples of Total Suspended Sediment (TSS) and gravity coring. Several analyses were then carried out on those samples; TSS analysis to determine the amount of suspended sediments in sea water that reflect the water quality for marine ecology, stratigraphic profile and sediment thickness pattern analyses to determine the sources of sediment, and grain-size analysis based on granulometry to determine deposition energy and grain-size distribution in the area. Those analyses were both conducted on-board Baruna Jaya VIII research vessel and P2O LIPI laboratory in Jakarta. The results showed that in Java Sea nearby Karimun Java Islands, the sediment supply came from the surrounding islands. Two sedimentary units were found in this area. The first units has thickness of tens centimeter from sea bed surface. It is characterized by grayish green color, grain size variation from clay to coarse sand, soft or low density and abundance with shells. The second unit is located beneath the first one, indicated by sharp contact. It is characterized by brownish color, higher density resembling the density of rock, less compacted and can be broken easily by hand, with occasionally thin carbon lenses or remnant of decomposed vegetation, and less shell or fossil At sea surface, TSS distribution shows value between 0.018 and 0.034 gr/l, with average of 0.025 gr/l, whereas at near bottom sea, it ranges between 0.024 and 0.030 gr/l, with average value of 0.027 gr/l. The granulometry shows that more than 50% of sediment is characterized by the abundance of grain size greater than 3 phi. It suggest that sea water around Karimun Java Islands was clear and the current was relatively calm. These conditions were relatively stable for a long time span. Those sea characteristics were important for successful growth of coral reefs and its complementary marine biotas. However, further studies and researches based on chemical and physical characteristics of sea water, and plankton and microbiology variation and abundances are necessary to confirm those presuppositions"

"Daerah penelitian X (Rendahan Cipunegara, Cekungan Jawa Barat Utara) merupakan salah satu cekungan back-arc di Indonesia yang berpotensi memiliki prospek hidrokarbon. Interpretasi struktur dan stratigrafi telah dilakukan pada data seismik 3D PSTM dengan dua data sumur di daerah tersebut untuk melihat kondisi geologi bawah permukaan secara lebih detail. Selain itu juga dilakukan analisa atribut amplitudo RMS untuk melihat perubahan litologi batuan secara lateral.Hasil interpretasi struktur dan stratigrafi menunjukkan adanya arah pola patahan Utara - Selatan pada Formasi Batu Raja dan Talang Akar serta arah pola patahan Barat - Timur pada Basement. Hasil analisa atribut amplitudo RMS dengan analisa jendela 20 ms menunjukkan adanya pola reef build-up pada Formasi Batu Raja dan pola channel pada Formasi Talang Akar.

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Study area of X (Cipunegara Low, North West Java Basin) is one of back-arc basins in Indonesia that potentially has hydrocarbon prospect. Structural and stratigraphic interpretation have carried out to the PSTM 3D seismic data along two wells data at that region to characterize more detail about the geological condition of subsurface. Furthermore, RMS amplitude analysis has been done to observe the lithology changes laterally.The result of structural and stratigraphic interpretation shows the existance of North ? South oriented faults at Batu Raja and Talang Akar Formation, and also East ? West oriented faults at Basement. The RMS amplitude attribute analysis with 20 ms window analysis shows the existance reef build-up pattern at Batu Raja Formation and channel pattern at Talang Akar Formation."