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"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"

"Perubahan dalam lingkungan oleh aktivitas manusia dapat berasosiasi dengan akumulasi logam berat dan berpotensi meninggalkan jejak antropogenik dalam rekaman sedimen laut. Penelitian akan kondisi kemostratigrafi dilakukan untuk menentukan pengaruh aktivitas antropogenik di Perairan Banggai, yang dinilai tinggi karena fungsinya sebagai wilayah penangkapan ikan dan berdekatan dengan Pulau Taliabu, kepulauan agrikultural dengan potensi tambang yang tinggi. Penelitian ini dilakukan dengan melakukan penanggalan umur (dating) dengan isotop 210Pb, analisis logam berat, distribusi ukuran butir, dan kandungan TOC untuk menganalisis dan merekonstruksi perubahan lingkungan. Penanggalan menggunakan isotop 210Pb dilakukan menggunakan spektrometer alfa (AAS), logam berat dianalisis menggunakan spektrometri emisi optikal (ICP-OES), distribusi ukuran butir dianalisis menggunakan difraksi laser (LDS), dan kandungan TOC dianalisis menggunakan LOI. Hasil analisis menunjukkan bahwa distribusi konsentrasi logam berat dalam sedimen core BC-06 menghasilkan nilai geo-accumulation index dan enrichment factor yang rendah, dan menunjukkan bahwa sumber logam berat yang ditemukan merupakan campuran alamiah dan antropogenik. Jejak logam berat dengan pengaruh antropogenik dalam sedimen core BC-06 dapat dibagi menjadi tiga periode, yaitu: (I) 1831-1927 AD, (II) 1927-1994 AD, dan (III) 1994-2022 AD, yang diinterpretasi berhubungan dengan ekspansi militer pada zaman pemerintahan Hindia-Belanda dan perkembangan berbagai sektor perekonomian Indonesia modern.

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Changes in the environment by human activities is associated with heavy metal accumulation and can potentially leave anthropogenic traces in marine sediment records. Research focusing on the chemostratigraphic condition was done to determine the impacts made by anthropogenic activities in Banggai Waters, that are considered high because of its function as fishing grounds and is located near Taliabu Islands, which are agricultural lands with high mining potential. This research was done by Pb-210 dating, heavy metal, grain size distribution, dan TOC content analyses, to analyse and reconstruct environmental changes. Pb-210 dating was conducted by alpha spectrometer (AAS), heavy metal analysis was conducted by optical emission spectrometry (ICP-OES), grain size distribution analysis was conducted by laser diffraction (LDS), and TOC content analysis was conducted by the LOI method. Results show that heavy metal concentration distribution in sediment core BC-06 yield low values for geo-accumulation index (Igeo) and enrichment factor (EF), and showed that the metals found has a mixed source of natural and anthropogenic. Heavy metal traces with anthropogenic influence can be divided into three periods, such as: (I) 1831-1927 AD, (II) 1927-1994 AD, dan (III) 1994-2022 AD, which are interpreted as related to the military expansion during The Dutch’s colonialism, alongside the development of various economic sectors in modern Indonesia."