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Cekungan Kutai merupakan cekungan terluas di Indonesia. Secara fisiografis, terdapat 3 zona berorientasi utara ke selatan yang membagi Cekungan Kutai pada bagian barat hingga timur. Penelitian biostratigrafi terhadap sedimen berumur tersier di cekungan Kutai penting untuk dilakukan karena dapat meningkatkan akurasi pembatasan umur relatif bagi masing-masing satuan batuan dan peristiwa-peristiwa penting seperti sejarah pembentukan cekungan Kutai. Penelitian terdahulu mengenai sedimen Tersier yang lebih tua daripada Miosen Tengah masih sangat sedikit, terutama penelitian mengenai stratigrafi khususnya biostratigrafi yang dinilai sangat penting. Maka dari itu penelitian ini akan membahas biostratigrafi cekungan Kutai yang berada di pulau Kalimantan bagian Timur dan berumur lebih tua daripada Miosen Tengah, tepatnya pada umur Eosen Akhir hingga Oligosen. Penelitian ini dilakukan berdasarkan kandungan fosil foraminifera yang terdapat pada perconto batuan sedimen dari sumur pengeboran ILM untuk mengetahui zonasi umur, persebaran fosil, dan lingkungan pengendapan batuan yang terdapat dalam sumur pengeboran tersebut. Analisis fosil foraminifera juga akan dilengkapi oleh data fosil nanoplankton sebagai data pelengkap yang dapat meningkatkan ketelitian dari studi biostratigrafi yang dilakukan.

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Kutai Basin is the largest sedimentary basin in Indonesia. Physiographically, there are three zones with N-S orientation that divide Kutai Basin from the west side until the east side. Researches related to biostratigraphy of tertiary Kutai basin is important to do because it can enhance the accuracy of age determination within sediment layers and it can help reconstruct the history of Kutai Basin. Previous researches related to biostratigraphy in tertiary Kutai Basin which is older than Middle Miocene is very limited, so the goal of this research is to explain the biostratigraphy of Kutai Basin older than Middle Miocene, from Late Eocene to Oligocene to be exact. This research will be based on foramifera fossils contained in sedimentary rocks of ILM drilling well to explain age zonation, fossil distribution, and sediment depositional environment of the drilling well. Foraminifera fossil analysis will also be complemented with nannoplankton fossil as the secondary data to increase the accuracy of this biostratigraphy research.

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"Sungai Cipamingkis termasuk ke dalam Formasi Jatiluhur yang memiliki umur Miosen Tengah-Miosen Akhir, serta memiliki litologi batuan sedimen campuran silisiklastik dan karbonat dengan kandungan foraminifera besar. Pemahaman mengenai distribusi dan karakteristik foraminifera besar pada batuan sedimen campuran silisiklastik dan karbonat dapat membantu menginterpretasikan lingkungan pengendapan dan sedimentasi pada suatu daerah. Pada studi ini, dilakukan metode stratigrafi terukur dan analisis petrografi dari menghasilkan empat fasies batuan sedimen karbonat yaitu Foraminiferal Packestone, Foraminiferal Rudstone, Foraminiferal Bivalvia Rudstone, dan Coral Foraminiferal Bindstone dan fasies batuan sedimen campuran silisiklastik dan karbonat, yaitu Foraminiferal Algae Sandy Allochem Limestone, Quartz Muddy Sandstone, Foraminiferal Algae Allochem Sandstone, Foraminiferal Bivalvia Sandy Allochem Limestone. Berdasarkan kandungannya, terdapat lima genus foraminifera besar, yaitu Heterostegina (Ht), Operculina (Op), Lepidocyclina (Le), Amphistegina (Amp), dan Cycloclypeus (Cy) yang menunjukan lingkungan laut dangkal dengan salinitas normal. Pengendapan pada daerah penelitian dibagi menjadi empat fase yang berhubungan dengan naik dan turunnya muka air laut, sehingga terjadinya pencampuran berupa punctuated mixing dan facies mixing. Lingkungan pengendapan daerah penelitian masuk ke dalam lingkungan laut zona foreslope hingga open shelf.

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The Cipamingkis River is included in the Jatiluhur Formation which has a Middle Miocene-Late Miocene age, and has a sedimentary rock lithology of mixed of siliciclastic and carbonate with large foraminifera content. An understanding of the distribution and the characteristics of large foraminifera in a mixed siliciclastic and carbonate sedimentary rocks can help interpreting the depositional and sedimentary environment of an area. In this study, measured stratigraphic methods and petrographic analysis were carried out to produce four carbonate sedimentary rock facies, namely Packestone Foraminiferal, Rudstone Foraminiferal, Bivalvia Rudstone Foraminiferal, and Bindstone Coral Foraminiferal and a mixed siliciclastic and carbonate sedimentary rock facies, namely Algae Sandy Quartz Foraminiferal, Foraminiferal Muddy Sandstone, Foraminiferal Algae Allochem Sandstone, Foraminiferal Bivalvia Sandy Allochem Limestone. Based on the content, there are five larger foraminifera genera, namely Heterostegina (Ht), Operculina (Op), Lepidocyclina (Le), Amphistegina (Amp), and Cycloclypeus (Cy) which show a shallow marine environment with normal salinity. Sedimentation in the study area is divided into four phases associated with the rising and the falling of sea levels, resulting in a mixing in the form of punctuated mixing and facies mixing. The depositional environment of the study area falls into the marine environment, from the foreslope zone to the open shelf."

"Pesisir selatan Jawa Timur memiliki potensi kebencanaan terutama tsunami yang cukup tinggi. Untuk tujuan mitigasi, selain memperingatkan warga mengenai bahaya tsunami, perlu juga dilakukan penelitian sejarah kejadian tsunami karena ada kemungkinan pengulangan kejadian. Catatan sejarah tsunami di Jawa Timur banyak mengambil tempat di Pacitan dan Banyuwangi, padahal Lumajang beserta beberapa kabupaten lain menjadi daerah yang sangat rawan tsunami juga. Maka dari itu, penelitian ini memilih daerah Lumajang, lebih tepatnya Kecamatan Tempeh sebagai lokasi penelitian. Penelitian ini bertujuan untuk mengidentifikasi endapan paleotsunami menggunakan empat metode, yaitu granulometri, XRF, Loss on Ignition (LOI), dan analisis mikrofauna. Dari pengamatan di lapangan dan karakter lapisan, berdasarkan pengamatan megaskopis, kandidat endapan paleotsunami pada sampel core JTM-11 terdapat pada kedalaman 142-150 cm. Berdasarkan analisis laboratorium yang berupa analisis granulometri, XRF, dan LOI, didapatkan bahwa karakter dari endapan kandidat paleotsunami tidak menunjukkan karakter endapan paleotsunami yang cukup signifikan dan representatif. Untuk analisis LOI sendiri juga menunjukkan angka yang sangat rendah baik di lapisan kandidat dan non kandidat. Selain itu tidak ditemukan adanya mikrofauna pada lapisan kandidat paleotsunami.

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The southern coast of East Java has quite high potential for disasters, especially tsunamis. For mitigation purposes, apart from warning residents about the dangers of tsunamis, it is also necessary to research the history of tsunami events because there is a possibility of recurrence. Historical records of tsunamis in East Java mostly take place in Pacitan and Banyuwangi, even though Lumajang and several other districts are areas that are very prone to tsunamis as well. Therefore, this research chose the Lumajang area, more precisely Tempeh District as the research location. This research aims to identify paleotsunami deposits using four methods, namely granulometry, XRF, Loss on Ignition (LOI), and microfauna analysis. From field observations and layer characteristics, based on megascopic observations, candidate paleotsunami deposits in the JTM-11 core sample are found at a depth of 142 – 150 cm. Based on laboratory analysis in the form of granulometry, The LOI analysis itself also shows very low numbers in both the candidate and non-candidate layers. Apart from that, no microfauna was found in the paleotsunami candidate layer."

"Perairan utara Papua berada pada lokasi yang strategis, dimana merupakan posisi salah satu pintu masuk arus lintas Indonesia (arlindo) yang merupakan bagian dari siklus oseanografi global. Sedimen laut dapat memberikan data mengenai keadaan lingkungan sekitarnya yang relatif lengkap dan tidak terganggu hingga jutaan tahun. Bukti perubahan lingkungan yang terekam pada sedimen laut berdasarkan karakteristik sedimen dan kandungan foraminifera pada periode transisi Pleistosen dan Holosen juga masih belum banyak dipelajari. Periode transisi Pleistosen-Holosen dapat menimbulkan dampak perubahan lingkungan yang dapat diteliti perbedaan akibat perubahan iklim tersebut. Kondisi tersebut dapat menimbulkan dampak perubahan lingkungan, paleogeografi, dan sumber daya alam yang signifikan. Variasi kelimpahan dan kumpulan foraminifera sendiri merupakan respons adaptif dari foraminifera terhadap perubahan lingkungan dengan habitatnya. Sedimen yang terdapat pada perairan Utara hingga Barat Jayapura ini kemudian dianalisis menggunakan metode Analisis Foraminifera, XRF, Granulometri dan LOI. Berdasarkan hasil kurva dari keempat metode yang dilakukan, dicurigai batas antara Kala Pleistosen dan Holosen berada di kedalaman 61 cm. Hasil tersebut yang digunakan untuk mengidentifikasi perbedaan komposisi foraminifera dan karakteristik sedimen akibat perubahan iklim yang terjadi.

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The waters of northern Papua are in a strategic location, which is the position of one of the entrances to the Indonesian cross flow (arlindo) which is part of the global oceanographic cycle. Marine sediments can provide data about the condition of the surrounding environment that is relatively complete and undisturbed for millions of years. Evidence of environmental changes recorded in marine sediments based on sediment characteristics and foraminifera content during the Pleistocene and Holocene transition periods has also not been widely studied. The Pleistocene - Holocene transition period can cause the impact of environmental changes which can be studied for differences due to climate change. These conditions can result in significant changes in the environment, paleogeography and natural resources. Variations in the abundance and collection of foraminifera themselves are an adaptive response of foraminifera to environmental changes in their habitat. The sediment found in the waters north to west of Jayapura was then analyzed using Foraminifera Analysis, XRF, Granulometry and LOI methods. Based on the curve results from the four methods used, it is suspected that the boundary between the Pleistocene and Holocene times is at a depth of 61 cm. These results are used to identify differences in foraminifera composition and sediment characteristics due to climate change."

"Penelitian foraminifera bentik telah dilakukan tanggal 19 November - 3 Desember 1995 di Delta Solo dan Porong Jawa Timur untuk mengetahui distribusi dan kelimpahan foraminifera bentik dan untuk mengetahui foraminifera aglutinin di Delta Solo dan Porong. Untuk itu telah diambil sampel sedimen dengan menggunakan Van Veen grab di 15 stasiun pada masing-masing delta, kemudian dianalisis di laboratorium.Untuk mengetahui keterkaitan antara komunitas foraminifera bentik dan beberapa faktor lingkungan yang berpengaruh dalam kehidupan biota ini, maka dilakukan juga pengukuran terhadap sifat fisik perairan seperti kedalaman , salinitas, PH dan turbiditas. Hasil analisa laboratorium kemudian dibagi ke dalam 3 kategori yaitu melimpah, umum dan jarang. Penelitian ini bertujuan untuk mengetahui distribusi dan kelimpahan foraminifera bentik dan untuk mengetahui foraminifera aglutinin di Delta Solo dan Porong.Hasil analisis menunjukkan terdapat 53 spesies foraminifera bentik dengan jumlah individu 7288 yang termasuk dalam 10 famili di Delta Solo dan 37 spesies dengan jumlah individu 6223 yang termasuk dalam 9 famili di Delta Porong. Seluruh spesies yang dijumpai di dua delta tersebut termasuk dalam subordo Rotaliina, 1VIilioliina dan Textulariina. Spesies yang melimpah di Delta Solo adalah Ammonia beccarii dan Asterorotala trispinosa yang dijumpai di semua stasion penelitian. Terdapat 35 spesies yang termasuk kategori umum dan 16 species pada kategori jarang. Di Delta Porong dijumpai 6 spesies dalam kategori melimpah yaitu Ammonia beccarii, Asterorotalia trispinosa, Ammobcculites agglutinans, Haplophragmoides canariensis, Textularia pseudogramen dan Trochammina amnicola. Sedangkan spesies yang umum 16 species dan 15 species yang tergolong jarang.Sebaran dan kelimpahan foraminifera bentik di Delta Solo dan Porong dipengaruhi oleh beberapa faktor lingkungan terutama jenis substrat, pH dan turbiditas. Hasil pengamatan terhadap foraminifera aglutinin menunjukkan keadaan sebaliknya dan hasil foraminifera bentik secara umum, yaitu Delta Porong lebih kaya akan species dibandingkan dengan Delta Solo. Di Delta Solo di jumpai 5 species yang hanya dijumpai di II stasiun, sedangkan di Delta Porong dijumpai 6 jenis yang dijumpai di semua stasiun penelitian. Hal ini kemungkinan besar dipengaruhi oleh kondisi lingkungan perairan dan keadaan delta tersebut.

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Solo and Porong Deltas, located in East Java, have different morphological forms. The differences in morphological forms are due to the variation in the sediment types. Solo River which flows from Mount Lawu and Mount Merapi in Central Java supplies a large number of sediment to Solo Delta. The type of sediment of Solo Delta is dominated by clay, silt and fine sand. Porong River receives water from Brantas River which originates from Mount Semeru and Mount Arjuno. The type of sediment of Porong Delta is dominated by sand. Benthic foraminiferans, which live and grow at the bottom of the sediment, are sensitive to environmental changes. Distribution and abundance of benthic foraminifera depend on some environmental factors, and that various ecological factors influence each other.From 15 stations observed in Solo Delta and 15 stations in Porong Delta there was a difference either in the species number or in the number of individuals found. The species are belong to 3 subordos, i.e Rotaliina, Milioliina and Textulariina. The main difference between the two deltas was the abundance of species. The number of species found in Solo Delta were 53 and the number of individuals were 7288, while in Porong there were 37 spesies with 6223 individuals. The predominant species found in almost all stations in two deltas were Ammonia beccarii and Aslerorotalia trispinosa.In Solo Delta the common species found were Ammonia umbonata, Amphistegina lessonii, Bucella frigida, Elphidium crispum, E. craticulatum, E. advenum, E. lessonii, Calcarina calcar,Chrysalidinella dimorpha, Quinqueloculina sp, Q.semirrulum, Q. intricata, Nonion sp, Nonion depressulum, Triloculina trio ata, Reuse/la simplex, Pseudorotalia schroeteriana, Spiroloculina communis, Ammobaculites agglutinans, Textularia pseudogramen. The less common species found were Buliminella elegantissima, B. basicostata, Cymbaloporetta squwnmosa, Cibicides lobatum, Hauerina braayi, Heterostegina depressa, Lagena laevis, Lagena grad/lima, Loxostomum lobatum, L. limbatum, Massilina milled, Operculina ammonoides, Triloculina trigonula, Ammotium cassis, Haplophragmoides canariensis and Textularia sagittula.In Porong Delta, besides Ammonia beccarii and Asterorotalia trispinosa other species which were found abundant in almost all of the stations were Ammobaculites agglutinans, Haplophragmoides canariensis, Textularia pseudogramen and Trochammina amnicola. The latest species are agglutinated foraminifera which live well at the sandy sediment dominating Porong Delta.The common species were Adelosina semistriata, Ammotium cassis, Elphidium advenum, E craticulatum, E. lessonii, Pseudorotalia shroeteriana, Heterostegina depressa, Flintina bradyana, Operculina ammonoides, Quinqueloculina seminulum, Q. lamarchiana, Nonion sp, Reusella simplex, Triloculina tricarinata, spiroloculina commis, Textularia sagittula. The rare species found were Amphistegina lessonii, Calcarina calcar, Cibicides praecinctus, Crysalidinella dimorpha, Loxoslomum lobatum, L. limbatum, Miliolinella subrotunda, M sublineata, Nonion depressulum, N. cf asterizans, Qrbitolites duplex, Quinqueloculina cultrata, Q. venusta, Q. granulocostata, Triloculina trigonula.The range of salinity in Solo Delta was 15 - 32 %o and in Porong Delta was 10 - 30 %o. Previous researchers showed that foraminiferan species adapt and produce well at salinity between 15 - 40 %o. That means that the salinity in Solo Delta is probably more suitable for foraminifera than in Porong Delta. The everage pH in Solo Delta was 7,86 while in Porong Delta was 8,20. According to some researchers, foraminiferans were found abundant in lower pH. Turbidity in Solo Delta was between 33,0 - 87,5 NTU, while in Porong Delta areas was between 37,8 - 200 NTIJ. That means that the water in Solo Delta was clearer than in Porong Delta. Water clearance influences penetration of sunlight , and results in decreasing photosynthesis activities of plankton which leads to food deficiency. According to previous researchers the population of some foraminiferans decreases at zones with high turbidity. Those above factors might influence the distribution and abundance of the benthic foraminifera, of both deltas.The study of aglutinated foraminiferan was done simultaneously with the study of distribution and abundance of benthic foraminiferans in Solo and Porong Delta. From 15 stations studied in each delta 5 species were found in Solo Delta and 6 species were found in Porong Delta. All species belongs to 3 families, namely Lituoliidae, Textulariidae and Trochanuniniidae. The 5 species found in Solo Delta were Ammobaculites agglutinans, Ammotium cassis, Haplophragmoides carurriensis, Textularia pseudogramen and T. sagittula. In Porong Delta, besides those 5 species, another species, i.e. Throcarnmrna amnicola, was also found.In general, Porong Delta is richer than Solo Delta in number of species and number of individuals of species. This might be due to the differences in types of sediment and water conditions of both deltas."

"Daerah penelitian terletak pada Formasi Klapanunggal, di Kecamatan Klapanunggal, Kabupaten Bogor, Provinsi Jawa Barat dengan umur Miosen Tengah hingga Miosen Akhir. Tujuan dari penelitian ini adalah untuk mengidentifikasi kisaran umur litologi, karakteristik fasies, dan paleoekologi Formasi Klapanunggal. Metode yang digunakan dalam penelitian ini adalah pengumpulan data lapangan, pengukuran penampang stratigrafi, analisis petrografi, dan analisis mikropaleontologi. Berdasarkan analisis makroskopis melalui data lapangan dan analisis mikroskopis melalui analisis petrografi, didapatkan lima klasifikasi fasies pada daerah penelitian, yaitu Larger Foraminifera Floatstone, Larger Foraminifera Rudstone, Coral Bindstone, Skeletal Floatstone, dan Skeletal Rudstone. Berdasarkan distribusi dan kelimpahan foraminifera bentonik yang ada pada daerah penelitian yaitu Alveolinella quoyi, Amphistegina lessonii, Amphistegina radiata, Archaias angulatus, Asterorotalia yabei, Borelis melo, Elphidium craticulatum, Operculina ammonoides, Operculina complanata, Pyrgo depressa, Sphaerogypsina globulus, dan Triloculina oblonga, mencerminkan intensitas cahaya pada zona mesophotic sampai oligophotic menempel pada substrat berbutir kasar maupun halus dengan kedalaman air laut hingga 50 meter di bawah permukaan laut dan memiliki salinitas normal hingga hypersaline. Hidup pada zona tropis yang memiliki kandungan nutrisi yang rendah, sehingga foraminifera bersimbiosis dengan alga yang berperan sebagai sumber makanan bagi organisme.

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The research area is located in the Klapanunggal Formation, Klapanunggal District, Bogor Regency, West Java Province with an age of Middle Miocene to Late Miocene. The purpose of this study was to identify the age range of the lithology, facies characteristics, and paleoecological condition of the Klapanunggal Formation. The methods that used in this research were field data collection, stratigraphic cross-sectional measurement, petrographic analysis, and micropaleontological analysis. Based on macroscopic analysis trough field data and microscopic analysis through petrographical analysis, five facies classifications were obtained in the research area, namely Larger Foraminifera Floatstone, Larger Foraminifera Rudstone, Coral Bindstone, Skeletal Floatstone, and Skeletal Rudstone. Based on the distribution of benthic foraminifera in the area, namely Alveolinella quoyi, Amphistegina lessonii, Amphistegina radiata, Archaias angulatus, Asterorotalia yabei, Borelis melo, Elphidium craticulatum, Operculina ammonoides, Operculina complanata, Pyrgo depressa, Sphaerogypsina globulus, and Triloculina oblonga, reflecting light intensity in the mesophotic to oligophotic zone attached to coarse and fine grained substrates with sea water depths up to 50 meters under the sea level and having normal to hypersaline salinities. Living in tropical zone which have low nutrient content, so foraminifera are in symbiosis with algae which act as food sources for organisms."

"Daerah penelitian berada pada Formasi Klapanunggal tersusun atas batugamping berumur Miosen Tengah dan bagian dari Palung Bogor Utara. Tujuan penelitian ini adalah mengidentifikasi karakteristik fasies yang dikelompokan dalam asosiasi fasies, serta pemodelan biofasies dengan metode analisis kuantitatif klaster dengan fosil foraminifera bentonik pada daerah penelitian. Metode yang digunakan dalam penelitian ini adalah pengumpulan data lapangan, pengukuran penampang stratigrafi, analisis petrografi, dan analisis mikropaleontologi. Berdasarkan analisis makroskopis melalui data lapangan dan mikroskopis melalui analisis petrografi, didapatkan adanya F1 - Skeletal Packstone, F2 - Skeletal Wackestone,  F3 - Mudstone, F4 - Skeletal Floatstone, F5 – Skeletal Rudstone, F6 - Coral Bindstone. Fasies tersebut dikelompokan menjadi asosiasi fasies pada platform margin reef yang terbagi menjadi back reef dan reef front. Dari analisis mikroskopis didapatkan 12 spesies dan 4 genus foraminifera bentonik yang dilanjutkan adanya analisis biofasies menggunakan metode kuantitatif klaster sehingga mendapatkan Biofasies A – Amphistegina sp, Biofasies B – Asterorotalia sp, dan Biofasies C – Elphidium sp.  Dari kehadiran foraminifera tersebut dan asosiasi fasies dapat diketahui variasi lingkungan pengendapan daerah penelitian yang terbagi 2 yaitu fasies back reef memiliki hubungan dengan Asterorotalia sp  pada back reef inner dan Elphidium sp pada fasies back reef outer dengan batimetri 0 - 50 m, serta fasies dari reef front dengan hubungan pada biofasies Amphistegina sp dengan batimetri  50 - 100 m.

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The research area is in the Klapanunggal Formation composed of Middle Miocene limestone and part of the North Bogor Trench. The purpose of this study was to identify facies characteristics grouped in facies associations, as well as biofacies modeling using quantitative analysis methods clusters with benthic foraminifera fosils in the study area. The methods used in this study were field data collection, stratigraphic cross-sectional measurement, petrographic analysis, and micropaleontological analysis. Based on macroscopic analysis through field data and microscopic analysis through petrographic analysis, it was found that there were F1 - Skeletal Packstone, F2 - Skeletal Wackestone, F3 - Mudstone, F4 - Skeletal Floatstone, F5 - Skeletal Rudstone, F6 - Coral Bindstone. These facies are grouped into facies associations on the margin reef platform which is divided into back reef and reef front. From microscopic analysis, 12 species and 4 genera of benthic foraminifera were obtained, followed by biofacies analysis using cluster quantitative methods to obtain Biofacies A – Amphistegina sp, Biofacies B – Asterorotalia sp, and Biofacies C – Elphidium sp. From the presence of these foraminifera and facies associations, it can be seen that the variation of the depositional environment of the study area is divided into 2, namely the back reef facies having a relationship with Asterorotalia sp on the inner back reef and Elphidium sp on the outer back reef facies with a bathymetry of 0-50 m, and the reef front facies. with the relationship between the biofacies of Amphistegina sp with a bathymetry of 50 - 100 m."