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"Daerah Sukatani berada di Selatan Jawa memiliki potensi terjadi bencana tsunami yang diakibatkan oleh gempa bumi besar dari proses pergerakan di zona subduksi. Catatan sejarah kejadian tsunami di Selatan Jawa masih terbatas, sehingga perlu dilakukan penelitian identifikasi endapan paleotsunami. Daerah Sukatani dipilih sebagai lokasi penelitian karena belum ada penelitian mengenai paleotsunami di daerah ini. Penelitian ini dilakukan untuk mengetahui sejarah kejadian paleotsunami di daerah Sukatani yang masih sangat terbatas. Pengambilan sampel kode KRB 03 sepanjang 193 cm dilakukan di Pantai Karang Bolong, Kecamatan Surade, Kabupaten Sukabumi. Untuk mengetahui lapisan endapan paleotsunami dilakukan beberapa analisis laboratorium seperti analisis ukuran butir (granulometri), loss on Ignition (LOI), geokimia unsur jejak, dan analisis foraminifera. Dari analisis yang terlah dilakukan didapatkan satu lapisan endapan paleotsunami di kedalaman 164 hingga 186 cm. Hasil analisis ukuran butir diketahui lapisan endapan paleotsunami memiliki rata-rata ukuran butir antara kerikil halus hingga pasir halus, sortasi sedang hingga sangat buruk, kurtosis tipe very platykurtic hingga very leptokurtic, dan skewness tipe very fine skewed hingga very coarse skewed. Hasil analisis Loss on Ignition (LoI) diketahui lapisan endapan paleotsunami memiliki kandungan material organik yang rendah dan material karbonat yang lebih tinggi. Hasil analisis geokimia unsur jejak diketahui lapisan endapan paleotsunami memiliki kandungan unsur Ca dan Sr yang lebih tinggi. Hasil analisis foraminifera didapatkan foraminifera bentonik dengan lingkungan neritik tengah yang diperkirakan sebagai sumber endapan paleotsunami.

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The Sukatani area in southern Java has the potential for a tsunami disaster caused by a large earthquake from the movement process in the subduction zone. The historical record of tsunami events in southern Java is still limited, so it is necessary to conduct research on the identification of paleotsunami deposit. The Sukatani area was chosen as the research location because there was no research on paleotsunami in this area. This research was conducted to determine the history of ancient tsunami events in the Sukatani area which is still very limited. Sampling code KRB 03 along 193 cm was carried out at Karang Bolong Beach, Surade District, Sukabumi Regency. To determine the paleotsunami sediment layer, several laboratory analyzes were carried out such as grain size analysis (granulometry), loss on Ignition (LOI), trace element geochemistry and foraminifera analysis. From the analysis that has been carried out, it is found that one paleotsunami deposit layer is at a depth of 164 to 186 cm. The results of grain size analysis show that the paleotsunami sediment layer has an average grain size of fine gravel to fine sand, moderate to very poor sorting, very platykurtic to very leptokurtic types of kurtosis, and very fine skewed to very coarse skewed types of skewness. The results of the loss on Ignition (LOI) analysis show that the paleotsunami sediment layer has a low content of organic material and higher carbonate material. The results of trace element geochemistry analysis show that the paleotsunami sediment layer has higher levels of Ca and Sr. The results of foraminifera analysis obtained bentonic foraminifera with middle neritic environments which are thought to be the source of paleotsunami deposits."

"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."

"Pantai Bagedur berada di Kabupaten Lebak, Banten memiliki karakteristik sedimen yang diduga terendapkannya endapan tsunami purba. Daerah penelitian termasuk ke dalam Endapan Aluvium (Qa) dan Endapan Undak Pantai (Qc) pada Peta Regional Lembar Cikarang (Sudana & Santoso, 1992). Sampel sedimen lepas bawah permukaan diambil menggunakan metode lubang bor tangan pada delapan stasisun penelitian dengan kedalaman yang bervariasi. Penelitian kali ini berfokus terhadap studi provenance dari endapan tsunami purba dan juga karakteristiknya berdasarkan geokimia. Metode analisis yang digunakan berupa analisis petrografi, X-Ray Diffraction (XRD), dan X-Ray Fluorescence (XRF). Hasil analisis petrografi menunjukkan bahwa tipe provenance utama dari daerah penelitian menurut diagram Q-F-L dan Qm-F-Lt (Dickinson & Suzcek, 1979) adalah recycled orogen. Kerangka tektonik yang mempengaruhi dari tipe provenance recyceled orogen merupakan zona subduksi dan diinterpretasikan ada kaitannya dengan subduksi di selatan Pulau Jawa. Berdasarkan analisis XRD dan XRF, didapatkan bahwa didominasi oleh senyawa SiO2, Al2O3, dan Fe2O3 dan pada stasiun BG 06 memiliki unsur yang dominanas berasal dari Laut. Endapan tsunami mengalami erosi dan pelapukan yang cukup tinggi.

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Bagedur Coast in Lebak Districts, Banten has sediment characteristic that assumed as deposit of paleotsunami deposit. The Research area consisted of Alluvium Deposit (Qa) and Beach Terrace Deposit (Qc) from Geological Map of Cikarang (Sudana & Santoso, 1992). Loose Sediment sample have collected using Hand Auger drilling methods from eight observation stations with various depth. This research is focused in provenance study from paleotsunami deposit and geochemistry characteristics. The method that used is petrography analysis, X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF). The result of petrography analysis show the type of provenance from research area according to Q-F-L dan Qm-F-Lt diagram (Dickinson & Suzcek, 1979) is recycled orogen. Geological setting that control provenance type of recycled orogen is subduction tectonic regime and interpreted to be related with subduction in South of Java. Based on XRD and XRF analysis, SiO2, Al2O3, and Fe2O3 are the dominating compound and from BG 06 station can be concluded the dominant deposit is originate from marine environment. Paleotsunami deposit have been undergone extreme erosion and weathering."

"Hasil penelitian ini menjelaskan menjelaskan tentang karakteristik dari endapan banjir dengan metode granulometri. Penelitian ini berada pada daerah sekitar sungai Citarum, Bandung. Penelitian ini bertujuan untuk mendapatkan data terkait karateristik endapan banjir seperti sortasi, distribusi ukuran butir, tingkat skewness, dan tingkat kurtosisnya.  Penelitian ini dimulai dengan persiapan awal seperti studi literatur dan persiapan alat lapangan yang dilanjutkan dengan pengambilan data lapangan. Data yang didapatkan kemudian dianalisis dan kemudian hasil analisis tersebut dimuat dalam bentuk laporan akhir. Berdasarkan hasil penelitian, karateristik dari endapan banjir dapat dibagi menjadi 2 kelompok, yaitu endapan lanau-lempung dan endapan endapan pasir. Pada endapan lanau-lempung, endapan didominasi dengan tingkat sortasi baik, tingkat skewness berupa fine skewed dan tingkat kurtosis berupa leptokurtic. Sedangkan pada endapan pasir didapatkan tingkat sortasi yang beragam dan tingkat skewness berupa fine skewed, endapan ini merupakan endapan yang mendominasi pada sampel. Persebaran data memiliki tingkat leptokurtic dimana data terpuncak pada suatu nilai.

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The results of this research explain explaining the characteristics of the flood deposit using granulometry method. This research location is around the Citarum river, Bandung. This research aims to obtain data related to flood deposit characteristics such as sorting, grain size distribution, skewness level, and kurtosis level. The research began with preliminary preparations such as literature studies and preparation of field tools followed by field data collection. The data obtained is then analyzed and then the results of the analysis are published in the form of a final report. Based on the results of the study, the characteristics of the flood sediment can be divided into 2 groups, namely silt-clay deposit and sand deposit. In silt-clay depositi, sediments are dominated by well sorted sediment, the level of skewness is fine skewed, and the level of kurtosis is  leptokurtic. Whereas in sand deposits there are various levels of sorting and the level of skewness is fine skewed, these deposits are dominant in the sample. Data distribution has a leptokurtic level where the data peaked at a value."

"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 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."

"Daerah Cisolok, Sukabumi menjadi salah satu lapangan panas bumi yang memiliki manifestasi panas bumi seperti travertine, geyser dan hot pool. Keberadaan panas bumi ini memperlihatkan prospek dari adanya alterasi dan mineralisasi. Tujuan dari penelitian ini adalah untuk mengidentifikasi tipe dan persebaran suatu mineralisasi dan alterasi yang ada pada daerah penelitian, membuat model penampang alterasi, dan mengidentifikasi tingkat akurasi metode citra satelit dengan data lapangan yang diperoleh. Metode penelitian yang akan digunakan antara lain analisis data citra satelit seperti metode FFD, LST, dan PCA, lalu digunakan juga penelitian lapangan dan data lapangan tersebut dianalisis lebih lanjut dengan menggunakan analisis petrografi dan XRD. Hasil penelitian menunjukkan bahwa jenis alterasi yang ada pada daerah penelitian antara lain alterasi argilik, propilitik, dan filik. Hal ini dapat diidentifikasi melalui hasil kombinasi dari analisis petrografi, XRD, dan PCA. Tipe mineralisasi pada daerah penelitian adalah mineralisasi pirit yang diidentifikasi melalui hasil analisis petrografi dan XRD. Nilai akurasi metode FFD, LST, dan PCA dengan data penelitian lapangan pada daerah penelitian memiliki akurasi yang kurang baik, sedang, dan cukup baik. Hal ini disesuaikan dengan tingkat kesamaan dari hasil korelasi antara data lapangan dengan metode citra satet yang digunakan. Model penampang alterasi hidrotermal daerah penelitian memiliki sebaran tipe alterasi yang ditarik melalui satu garis penampang.

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The Cisolok area, Sukabumi is one of the geothermal fields that has geothermal manifestations such as travertines, geysers and hot pools. The existence of this geothermal shows the prospect of alteration and mineralization. The purpose of this study is to identify the type and distribution of mineralization and alteration in the study area, create a cross-sectional model of alteration, and identify the accuracy of the satellite imagery method with the obtained field data. The research methods that will be used include analysis of satellite image data such as the FFD, LST, and PCA methods, then field research is also used and the field data is further analyzed using petrographic analysis and XRD. The results showed that the types of alteration that existed in the study area were argillic, propylitic, and philic alterations. This can be identified through the combined results of petrographic analysis, XRD, and PCA. The type of mineralization in the study area is pyrite mineralization which was identified through the results of petrographic and XRD analysis. The accuracy values ​​of the FFD, LST, and PCA methods with field research data in the research area have poor, moderate, and quite good accuracy. This is adjusted to the level of similarity of the results of the correlation between the field data and the satellite image method used. The cross-sectional model of hydrothermal alteration in the study area has a distribution of alteration types drawn through one cross-sectional line."

"Penelitian ini membahas mengenai identifikasi faktor utama yang menjadi penyebab terjadinya peristiwa tanah longsor di Kota dan Kabupaten Sukabumi serta menentukan zona rawan bencana berdasarkan kelas-kelasnya yang disajikan dalam bentuk peta kerawanan bencana. Penelitian ini dilakukan dengan menggunakan metode analisis bivariat, yaitu menguji parameter independen berupa data titik keterjadian longsor terhadap parameter-parameter dependen yang diindikasikan menjadi penyebab terjadinya tanah longsor tersebut, diantaranya kemiringan lereng, litologi, tutupan lahan, vegetasi, kedekatan dengan kelurusan dan sungai, curah hujan dan kurvatur. Hasil penelitian menjelaskan bahwa parameter yang paling berpengaruh dalam keterjadian bencana longsor adalah parameter litologi, karena memiliki nilai Area Under Curve (AUC) terbesar dibanding parameter lainnya yaitu 0,823. Hasil penelitian juga menjelaskan bahwa potensi terjadinya longsor terbesar adalah pada bulan Desember dengan nilai AUC total 0,96 yang diperoleh dari campuran beberapa parameter yang sudah tervalidasi, yang memiliki nilai AUC > 0,6, yaitu litologi, tutupan lahan, dan curah hujan. Lokasi sebaran kejadian bencana tanah longsor dominan berada di wilayah utara daerah penelitian. Hasil penelitian ini menyarankan pada pembaca untuk memperhatikan tiga parameter tersebut sebelum melakukan proyek pembangunan di wilayah Kota dan Kabupaten Sukabumi.

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This research discusses the identification of the main factors that caused the occurrence of landslides in the City and District of Sukabumi and determines disaster-susceptibility zones based on their classes and presented in the form disaster susceptibility map. This research was conducted using the bivariate analysis method, which tested the independent variables in the form of landslide point data on the dependent variables indicated to be the cause of the landslide, including slope, lithology, land cover, vegetation, closeness to lineaments and rivers, rainfall and curvature. The results of the study explained that the most influential variable in the occurrence of landslides was the lithology factor, because it has 0.823 Area Under Curve (AUC) value, the largest one compared to other variables. The results also explained that the biggest potential for landslides was in December with a total AUC value of 0.96 obtained from a mixture of several validated variables, which had an AUC value> 0,6, those are lithology, land cover, and rainfall. The dominant landslide disaster distribution location is in the northern area of the study area. The results of this study suggest to the reader to pay attention to these three variables before carrying out development projects in the City and Sukabumi Districts."

"Pertumbuhan ekonomi yang pesat dapat berpengaruh pada perkembangan area pertambangan, sehingga diperlukan eksplorasi mineral berkelanjutan sebagai solusi permasalahan tersebut dengan menggunakan penginderaan jauh sebagai langkah awal eksplorasi. Penelitian ini bertujuan untuk mengidentifikasi zona alterasi pada daerah Bojong dan sekitarnya, zona alterasi tersebut ditentukan berdasarkan persebaran mineral penciri alterasi hidrotermal seperti klorit, alunit, epidot, serisit, illit, dan muskovit. Metode yang digunakan merupakan Principal Component Analysis (PCA) dan Band Ratio (BR), hasil analisis metode penginderaan jauh diverifikasi dengan studi lapangan dan analisis petrografi. Hasil penelitian ini berdasarkan integerasi metode PCA dan BR serta validasi studi lapangan menunjukkan bahwa zona alterasi hidrotermal yang ditemukan merupakan alterasi propilitik serta ditemukan mineral alterasi yang dapat ditambang berupa mineral zeolit. Zona alterasi hidrotermal dan persebaran mineral alterasi pada daerah penelitian teridentifikasi berada tersebar pada bagian selatan dan tenggara.

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Rapid economic growth can affect the development of mining areas, so suistainable mineral exploration is needed as a solution to problems by using remote sensing as the first step in exploration. This study aims to identify alteration zones in the Bojong area and its surroundings, the alteration zones are determined based on the distribution of minerals characteristic of hydrothermal alteration such as chlorite, alunite, epidote, sericite, illite, and muscovite. The methods used are Principal Component Analysis (PCA) and Band Ratio (BR), the results of the analysis of remote sensing methods are validated by field studies and petrographic analysis. The results of this study based on the integration of the PCA and BR methods as well as the verification of filed studies show that the hydrothermal alteration zones found are porphylitic alteration and the alteration minerals found to be minable are zeolite minerals. The hydrothermal alteration zone and the distribution of alteration minerals in the identified research area are scattered in the south and southeast."

"Sukabumi merupakan salah satu wilayah yang memiliki potensi bijih timbal. Pada area penelitian terdapat endapan mineral skarn dengan host rock batugamping. Namun, karakteristik host rock batugamping dan tipe skarn belum diketahui. Kedua hal tersebut perlu diketahui untuk kepentingan penentuan zona prospek bijih. Penelitian ini bertujuan untuk mengidentifikasi karakteristik batugamping di sekitar endapan skarn sehingga dapat diketahui tipe endapan skarn daerah penelitian. Penelitian menggunakan metode kuantitatif dan kualitatif pada analisis petrologi, petrografi, mineragrafi, pemodelan eksplisit, dan atomic absorption spectrometry (AAS). Karakteristik batugamping di sekitar endapan skarn terdiri dari parameter lithofasies, tingkat metamorfisme, jenis alterasi, jenis mineralisasi bijih, dan kadar bijih. Batuan yang ditemukan memiliki tiga kelompok, yaitu batugamping, metagamping, dan marmer. Lithofasies di sekitar endapan skarn terdiri dari wackestone, packestone, floatstone, rudstone, boundstone, litho-bioclastic limestone, dan marmer. Sementara itu, kelompok metagamping dan marmer mengalami metamorfisme dalam tiga tingkat, yaitu slighly metamorphed, moderately metamorphed, dan highly metamorphed. Batuan teralterasi progradasi dan retrogardasi. Mineral progradasi yang ditemukan didominasi klinopiroksen anggota aegirin, augit, hedenbergit, dan diopsid. Sementara alterasi retrogradasi menghasilkan mineral klorit, serpentin, epidot, amfibol, dan mineral bijih sulfida. Mineral bijih pada batuan terdiri dari pirit, pirhotit, sfalerit, dan galena dengan jenis mineralisasi fossil casted mineralization dan non-fossil casted mineralization dan kadar bijih didominasi unsur Pb dan Zn. Host rock mineralisasi bijih pada endapan skarn berupa boundstone dan unknown limestone facies yang paralel dengan boundstone. Mineralisasi pada fasies boundstone dikontrol oleh open space berupa moldic pore, sementara unknown limestone facies dikontrol oleh secondary pore. Endapan skarn daerah penelitian merupakan Pb-Zn skarn yang berada dalam posisi distal terhadap intrusi.

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Sukabumi is one of the areas that has lead ore potential. In research area, there is skarn mineral deposit with limestone as host rock. However, the characteristics of the limestone host rock and the type of skarn are not yet known. These two things need to be known for the purpose of determining the ore prospect zone. This research aims to identify the characteristics of limestone around the skarn deposits so that the type of skarn deposits in the study area can be identified. The research uses quantitative and qualitative methods in petrological, petrography, mineragraphy, explicit modeling, and atomic absorption spectrometry (AAS). The characteristics of limestone around skarn deposits consist of lithofacies, metamorphism level, alteration type, ore mineralization type, and ore grade. The rocks found have three groups, namely limestone, meta-limestone, and marble. Lithofacies around skarn deposits consist of wackestone, packestone, floatstone, rudstone, boundstone, litho-bioclastic limestone, and marble. Meanwhile, the metalimestone and marble groups have three levels of metamorphism, there are slighly metamorphed, moderately metamorphed, and highly metamorphed. The limestone is impacted by prograde and retrograde altered rock. The prograde minerals found were dominated by clinopyroxene members of aegirin, augite, hedenbergite, and diopsid. While retrogradation alteration produces chlorite, serpentine, epidote, amphibole, and sulfide ore minerals. The ore minerals in the rock consist of pyrite, pyrrhotite, sphalerite, and galena with the type of mineralization fossil casted mineralization and non-fossil casted mineralization and the ore grade is dominated by Pb and Zn elements. The host rock of ore mineralization in skarn deposits is boundstone and unknown limestone facies that is parallel to the boundstone. Mineralization in the boundstone facies is controlled by open space in the form of a moldic pore, while the unknown limestone facies is controlled by a secondary pore. The skarn deposit in the study area is a Pb-Zn skarn which is in a position distal to the intrusion."