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"Penelitian dilakukan pada Formasi Paciran yang berada di daerah Lamongan, Jawa Timur. Formasi Paciran ini tersusun atas batu gamping yang merupakan salah satu bahan baku dalam pembuatan semen. Tujuan dilakukannya penelitian ini yaitu menjelaskan mikrofasies, zona lingkungan pengendapan batugamping, tahapan, proses dan lingkungan diagenesis yang terjadi pada batugamping pada Formasi Paciran, Jawa Timur. Metode penelitian yang digunakan yaitu dengan pengamatan lapangan melalui pemetaan dan pembutan log stratigrafi (makroskopis) dan pengamatan laboratorium melalui analisis petrografi (mikroskopis). Dari hasil pengamatan secara makroskopis dan mikroskopis ditemukan sebanyak enam jenis fasies, yaitu Coral Framestone, Foraminifera Grainstone, Bivalvia Rudstone, Larger Foraminifera Rudstone, Larger Foraminifera Floatstone, dan Coral Floatstone. Fasies-fasies tersebut diendapkan pada lingkungan Platform Margin Reefs. Kemudian, untuk proses diagenesis yang berlangsung yaitu mikritisasi, sementasi, kompaksi, pelarutan, dan penggantian. Proses diagenesis ini terjadi dalam tiga tahapan diagenesis, yaitu eogenesis, mesogenesis, dan telogenesis . Kemudian, melalui proses dan tahapan tersebut menghasilkan fitur diagenesis yang dapat menentukan lingkungan diagenesis batugamping daerah penelitian yaitu zona marine phreatic, zona mixing, zona burial, zona meteoric phreatic dan zona meteoric vadose. Selain itu, berdasarkan fitur diagenesis batugamping di daerah penelitian, terdapat beberapa titik berpotensi sebagai akuifer, yaitu S1.5, S3.2, S5.1, S10, S12, S13, S16, S17, S20, S21, S22, dan S23.

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Research was carried out on the Paciran Formation in the Lamongan area, East Java. The Paciran Formation is composed of limestone which is one of the raw materials for making cement. The aim of this research is to explain the microfacies, environmental zones of limestone deposition, stages, processes and diagenetic environments that occur in limestone in the Paciran Formation, East Java. The research methods used are field observations through mapping and making stratigraphic logs (macroscopic) and laboratory observations through petrographic analysis (microscopic). From the results of macroscopic and microscopic observations, six types of facies were found, namely Coral Framestone, Foraminifera Grainstone, Bivalvia Rudstone, Larger Foraminifera Rudstone, Larger Foraminifera Floatstone, and Coral Floatstone. These facies are deposited in the Platform Margin Reefs environment. Then, the diagenesis processes that take place are micritization, cementation, compaction, dissolution and replacement. This diagenesis process occurs in three stages of diagenesis, namely eogenesis, mesogenesis, and telogenesis. Then, through these processes and stages, diagenetic features are produced that can determine the limestone diagenetic environment in the research area, namely the marine phreatic zone, mixing zone, burial zone, meteoric phreatic and meteoric vadose. In addition, based on the diagenesis features of limestone in the research area, there are several points that have the potential to be aquifers, namely S1.5, S3.2, S5.1, S10, S12, S13, S16, S17, S20, S21, S22, and S23."

"Prospek hidrokarbon di Cekungan Jawa Barat Selatan masih dipertanyakan dan perlu identifikasi lebih detail. Lokasi penelitian ini tepatnya berada di Anggota Konglomerat Formasi Bayah (Teb). Formasi ini di dominasi oleh konglomerat, batupasir kuarsa, batulempung, tuf, dan batu bara. Di Formasi Bayah, salah satunya, sungai cidahu dan cipanadogan ditemukan batuan serpih dengan indikasi rembesan minyak yang sudah mengering di sela-sela batuan. Rembesan minyak yang berada di batuan ini belum diketahui karakteristik lingkungan pengendapan dan kematangannya. Selain memiliki struktur yang kompleks, Formasi Bayah memiliki pemaparan litologi yang luas, salah satunya adalah batu bara. Batu bara yang berada di daerah penelitian memiliki luas ± 100 m yang tersebar di Sungai Cidahu, Cipanadogan, Cimandiri, dan Pantai Cibobos. Karakteristik batu bara Formasi Bayah pada daerah penelitian masih belum diketahui. Oleh karena itu, hal ini perlu diidentifikasi lebih lanjut dengan melakukan analisis pada penelitian ini agar dapat mengetahui kualitas batuan induk dan karakterisasi batu bara. Penelitian ini bertujuan untuk mengetahui kualitas batuan induk dan karakterisasi batu bara di Cekungan Jawa Barat Selatan di wilayah Formasi Bayah menggunakan analisis kromatografi gas, analisis kromatografi gas-spektropi massa, dan petrografi maseral. Empat sampel batuan serpih dan lima sampel batu bara dari daerah penelitian telah dikumpulkan dan dianalisis. Analisis kromatografi gas dan kromatografi gas-spektropi massa menunjukkan CDH 05, SHALE 01, dan SHALE 04 berada pada lingkungan pengendapan delta (terrigeneous) sedangkan, CP 04 berada pada lingkungan pengendapan transisi antara laut dan darat. Berdasarkan kematangan termalnya conto CDH 05, CP 04, SHALE 01, dan SHALE 04 berada pada tingkat kematangan awal (early mature), sehingga menunjukkan kualitas batuan induk yang cukup baik. Analisis petrografi maseral menunjukkan CDH 09, dan CMN 01 berada di lingkungan pengendapan hutan rawa basah, sedangkan CP 04, CP 07, PCBB berada pada hutan rawa yang sedikit dipengaruhi oleh pasang surut air laut, sehingga kualitas batu bara buruk. Dari hasil tersebut, dapat disimpulkan bahwa kualitas batuan induk memiliki kualitas yang cukup baik dan batu bara memiliki kualitas yang buruk.

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The prospect of hydrocarbons in the South West Java Basin is still questionable and needs more detailed identification. The exact location of this research in the Members of the Bayah (Teb) Formation Conglomerate. This formation is dominated by conglomerates, quartz sandstone, claystone, tuff, and coal. In the Bayah Formation, one of which, the Cidahu and Cipanadogan rivers are found with shale rocks with an indication of oil seepage that has dried up between the rocks. Oil seeps in these rocks are not yet known characteristics of the depositional environment and its maturity. Besides having a complex structure, the Bayah Formation has extensive lithological exposure, one of which is coal. Coal in the study area has an area of ± 100 m spread over the Cidahu River, Cipanadogan, Cimandiri, and Cibobos Beach. The characteristics of the Bayah Formation coal in the study area are still unknown. Therefore, this needs to be further identified by analyzing this study in order to find out the quality of source rock and coal characterization. This study aims to determine the quality of the source rock and the characterization of coal in the South West Java Basin in the Bayah Formation region using gas chromatography analysis, gas chromatography-mass spectrophy analysis, and mass petrography. Four shale rock samples and five coal samples from the study area were collected and analyzed. Analysis of gas chromatography and gas chromatography-mass spectrophy show that CDH 05, SHALE 01, and SHALE 04 are in the terrigeneous deltaic environment whereas, CP 04 in the transitional depositional environment between marine and land. Based on the thermal maturity, the samples of CDH 05, CP 04, SHALE 01, and SHALE 04 are early mature level, show that the quality of the source rock has quite good. Mass petrographic analysis shows CDH 09, and CMN 01 are in the sedimentation environment of wet forest swamp, while CP 04, CP 07, PCBB are in forest swamp which is slightly affected by tidal water, so that of coal has a poor quality. From these results, it can be concluded that the quality of source rock has a fairly good quality and coal has a poor quality."