Abstract. Seismic oceanography is integrated discipline between seismology and physical oceanography that can be used to investigate phenomenon in water column. Seismic oceanography displays fine structure of water column seismically and in wide range. The aim of this research was to measure temperature in Sulawesi Sea with CTD and seismic data. The benefits of this research were to create integrity and effectiveness in seismic and oceanographic surveys as well as to help develop OTEC (Ocean Thermal Energy Conversion) studies in Indonesia. The acquisition of seismic and CTD data in line 17 Sulawesi Sea conducted by P3GL on Mei-Juni 2016. Data processing was conducted in Februari-April 2017 and divided into three processes: seismic data processing using ProMax 2D software, synthetic seismogram processing using Hampson-Russell software, and mapping temperature using Ocean Data View software. The results showed that temperature in Sulawesi Sea based on CTD data ranged 4.7-30.3 Ԩ, and temperature based on the sesimic data ranged 4.49-30.29 ԨǤ This difference occured due to difference in vertical sampling between CTD and sound velocity semblance. Acoustic impedance in Sulawesi Sea ranged 1.529-1.578 MRy. Vertical and horizontal resolution of seismic data in this research were 6.3 m and 93.5 m, respectively. It's well established that sound velocity the main contribution to acoustic impedance. Correlation between seismic field with synthetic seismogram from CTD data is 0.7. IntroductionThe information about physical oceanography can be obtained by satellite imagery, ground check, and acoustic survey. Thermohaline circulation is the primary forcing mechanism that keeps the ocean conveyor belt in perpetual motion, regarding ocean processes helps build a comprehensive understanding of the ocean's role in the distribution of heat around the planet and thereby affecting climate. Seismic oceanographer investigate oceanic thermohaline finestructure based on temperature and salinity profiles [1].Seismic method is one of sea exploration method based on measurement of sound waves propagating on earth layer medium then reflected and refracted [2]. Seismic method has three application with different requirements for band-width and depth-width; engineering seismology, exploration seismology, and earthquake seismology. Engineering seismology is used to derive a velocity-depth model for near surface with bandwidth 1000 Hz and depth down to 1 km. Exploration seismology is used to derive an image of subsurface with bandwidth 100 Hz and depth of interest down to 10 km. Earthquake seismology is used to investigate oceanic and continental crust with bandwith 10 Hz and depth of interest down to 100 km [3].Seismic oceanography is recently developed approach for investigating water column using seismic reflection method. This method utilizies vibration source from air gun and fired to water, the waves are exposed to the medium and energy. This propagation will be influenced by many factors, such as offset,

his paper reviews submarine landslide potential in the eastern Indonesia by analyzing published and recently acquired bathymetric data and interpreting seismic reflection data. This review aims to study and invent hazards that might affect seafloor infrastructure construction such as optic cables, especially in the eastern Indonesia Region. The hazards were also recognized as source of tsunamis such as Palu Bay 2018 and Babi Island north of Flores Island in 1992. On the other hand, submarine landslide is a common process of basin fill sedimentation in the region. As blessed with many active volcanoes, it has 130 of total the world 400, Indonesia should aware of tsunami induced by volcanoes especially the ones closed to the sea. There are five active volcanoes frequently produce tsunami in historical times: Anak Krakatau, Sunda Strait; Makian, Maluku Province; Sangihe, Sulawesi; Teon and Nila, Banda Sea; and Iliwerung, Lembata Island, east Lesser Sunda Islands.Key words: submarine landslide, volcanic tsunami, seafloor infrastructure, eastern Indonesia Makalah ini menelaah potensi langsoran dasar laut di wilayah Timur Indonesia melalui analisis publikasi dan data batimetri yang baru diambil serta penafsiran data seismic refleksi. Tinjauan longsoran dasar laut dimaksudkan untuk mempelajari dan menginventarisasi bencana yang mungkin bisa mempengaruhi pembangunan infrastruktur dasar laut seperti halnya kabel optic, terutama di wilayah Timur Indonesia. Bencana tersebut telah dikenal sebagai sumber beberapa tsunami seperti Teluk Palu 2018 dan Pulau Babi utara Lombok di tahun 1992. Sebaliknya, longsoran dasar laut merupakan proses sedimentasi pengisian cekungan yang biasa terjadi di wilayah tersebut. Dikarunia akan gunungapi terbanyak di dunia, sebab memiliki 130 dari 400 dunia, Indonesia harus menyadari bahaya tsunami yang ditimbulkan oleh aktivitas gunungapi terutama yang dekat laut. Terdapat lima gunungapi aktif yang sering menghasilkan tsunami dalam sejarah: Anak Krakatau, Selat Sunda; Makian, Provinsi Maluku; Sangihe, Sulawesi; Teon dan Nila, Laut Banda; dan Iliwerung, Pulau Lembata, Nusa Tenggara Timur.Kata kunci: longsoran dasar laut, tsunami gunungapi, infrastruktur dasar laut, Wilayah Indonesia Timur

Pulau Marore adalah salah satu pulau terluar yang mempunyai arti strategis bagi Negara Kesatuan Republik Indonesia karena pulau ini merupakan salah satu titik pangkal terluar wilayah Indonesia dalam penentuan batas wilayah dan gerbang ekonomi Indonesia dengan Filipina. Oleh karena itu keberadaan Pulau Marore baik secara fisik maupun secara politik harus dipertahankan. Permasalahan yang terjadi di Pulau Marore adalah adanya aktifitas abrasi yang berlangsung secara berkesinambungan. Abrasi ini menjadi salah satu kendala dalam pembangunan sarana infrastruktur untuk kegiatan ekonomi dan pengembangan wilayah di Pulau Marore. Beberapa hal yang menjadi penyebab terjadinya abrasi di lokasi ini, di antaranya adalah adanya perbedaan kemiringan morfologi dasar laut yang cukup besar dari pantai ke arah laut, kondisi hidrodinamika laut yang terkait dengan musim, tipe pantai dan posisi Pulau Marore yang berada di antara dua perairan besar. Perbedaan morfologi dasar laut yang cukup besar (di atas 5º) dari pantai ke arah laut menyebabkan daerah gelombang pecah menjadi lebih dekat dengan pantai dan penetrasi gelombang menjadi lebih jauh ke arah daratan. Hempasan (run up) gelombang di pantai ini menyebabkan terjadinya arus sejajar pantai dan arus tegak lurus pantai yang membawa material dari darat ke arah laut sehingga terjadi pengikisan material darat oleh air laut secara berkesinambungan. Abrasi pantai oleh gelombang paling parah terjadi pada saat musim barat terutama pada tipe pantai berpasir dan tipe pantai berbatu yang tersusun dari batuan lepas. Secara teknis sangat sulit untuk mengatasi masalah abrasi di Pulau Marore. Cara yang paling efektif adalah dengan menjaga dan tidak merubah bentang alam dan garis pantai agar tidak mengalami kehancuran lebih parah. Kata kunci : abrasi, gelombang, morfologi Marore Island is one of the outer islands that have a strategic significance for the Republic of Indonesia since the island a gate of Indonesian economy with the Philippines. Therefore, the existence of the island both physically and politically has to be maintained. The problems are abrasion of beach activities. It has become the obstacles in the development of infrastructure for economic activity and development of the island. The cause is the difference slope of the seabed morphology, marine hydrodynamics conditions associated with season, type and position of Marore Island beach which is localed between two large waters. The difference slope of seabed morphology from the coast to the sea is above 5° causing breakwater closer to the shore and wave penetration become farther toward the mainland. The waves generated longshore current and rip current to the coast transporting material from land to sea. It caused erosion of the terrestrial material by sea water continuously. The most severe abrasion occurs during the dry season, especially on the sandy beaches and rocky types beaches which composed of loose rock. To solve the problem of abrasion on the island of Marore technically is very difficult. The most effective way is by maintaining the landscape and coastline from severe destruction. Key words: abrasion, wave, morphology

Tujuan penelitian seismik saluran banyak di Laut Flores, Nusa Tenggara Timur adalah untuk mengetahui kondisi geologi bawah permukaan dasar laut. Daerah penelitian merupakan daerah yang aktif secara tektonik dan diekspresikan dalam bentuk prisma akresi, vulkanik tidak aktif dan sesar-sesar aktif yang membentuk morfologi dasar laut. Berdasarkan penafsiran stratigrafi seismik lapisan bawah permukaan dasar laut terdiri dari empat satuan batuan: Batuan Dasar, Prisma Akresi, Gunungapi Bawah Laut, dan Sedimen Klastika. Sedimen Klastika ini dibagi menjadi lima unit. Kata kunci: seismik, morfologi dasar laut, sesar aktif, Laut Flores The purpose of the study of seismic multi channel in Flores Sea, East Nusa Tenggara is to recognize subsurface geology condition. The study area is an active tectonic that expressed by accretion prisms, inactive vulcanic and active faults form seabed morphology. Based on seismic stratigraphy interpretation, the study area is composed of four rocks units: Basement rocks, Accretionary Wedge, Seamount, and Clastic Sediments. This clactic sediment is divided into five units. Keywords: seismic, seabed morphology, active fault, Flores Sea

ABSTRAKOstracoda merupakan kelompok mikro-organisme yang dapat terawetkan dalam sedimen dasar laut, termasuk dasar perairan sekitar Pulau Bangka, Sulawesi Utara. Pulau ini terkenal akan keindahan alam bawah laut dan penambangan bijih besi di kawasan pesisir. Perubahan lingkungan di pesisir tersebut secara tidak langsung berpengaruh terhadap kondisi dasar perairan laut sebagai habitat biota. Tujuan dari penelitian ini adalah untuk mengetahui respon ostracoda terhadap perubahan lingkungan perairan tersebut. Studi ini menggunakan 10 sampel sedimen dasar laut hasil cucian dilanjutkan dengan analisa mikropaleontologi (tahap penjentikan, identifikasi spesies, penghitungan spesimen dari setiap spesies, pengolahan data, dokumentasi spesimen) dan analisa sedimentologi (SEM-EDX). Keterdapatan Bairdopillata, Neonesidea, Paranesidea dan Quadracythere (BL16-010) yang hidup berasosiasi dengan kondisi terumbu karang mencerminkan suatu perairan dalam kondisi cukup bagus. Di titik lokasi lain (BL16-015 dan BL16-030) ditemukan mikrofauna dengan cangkang abnormal (rusak, kehitaman) yang mengandung C (59-86%), Al 2 O 3 (2%), SiO 2 (1-7%), dan MnO (2%). Dijumpainya cangkang abnormal merupakan salah satu respon mikrofauna terhadap perubahan lingkungan di daerah penelitian. ABSTRACTOstracoda is a group of micro-organism that could be preserved in marine sediments, including on the seafloor of Bangka Island, North Sulawesi. This island is famous as beautiful underwater place and iron mining in the coastal area. The environmental changes in the coastal area indirectly influence the seafloor condition as biotic habitats. The purpose of this study is to know the response of ostracoda to this coastal environmental change. This study used ten washed residue of surface sediment samples followed by micropaleontological analysis (picking, identification of species, specimen calculation every species, data processing, specimen documentation), and sedimentological analysis (SEM-EDX). The occurrences of Bairdopillata, Neonesidea, Paranesidea dan Quadracythere (BL16-010) that associated with coral reef communities reflect a good marine condition. In another sampling location (BL16-015 and BL16-030), it is found abnormal microfaunas (broken, blackish) that composed of C (59-86%), Al 2 O 3 (2%), SiO 2 (1-7%), and MnO (2%). The finding of these abnormal shells is one of the microfaunal response to environmental changes in the study area.