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Despite its importance, sea surface paleoproductivity of the western Savu Strait is not well studied. Results from previous studies at the nearby Southwest Sumba and Sumba Strait might not be applicable due to the oceanographic difference. Foraminiferal proxies from gravity core ST10 were applied to generate sea surface paleoproductivity and thermocline depth reconstruction. Foraminiferal Accumulation Rate and Benthic Foraminiferal Accumulation Rate were used as paleoproductivity proxies while the thermocline dwellers’ relative abundance was applied as the thermocline depth proxy. This study suggested paleoproductivity increase during the Last Glacial Maximum (LGM)–~16 ka BP and Holocene (after ~11.65 ka BP) in the western Savu Strait. Thermocline depth was relatively shallower during the LGM–Last Deglaciation and became deeper afterwards. Paleoproductivity increase at LGM–~16 ka BP was caused by the Australian-Indonesian winter monsoon (AIWM)-like condition, characterized by intense coastal upwelling while the Holocene paleoproductivity increase was related to the abrupt rainfall increase which enhanced terrestrial/riverine input. Thermocline depth variability in the western Savu Strait is in-phase with thermocline depth variability in the Java upwelling region, characterized by a shallower thermocline during the LGM–Last Deglaciation (before ~11.65 ka BP) and a deeper thermocline during the Holocene (after ~11.65 ka BP). This thermocline depth shifting indicates a strong Australian-Indonesian Monsoon (AIM) influence on the paleoceanography of the western Savu Strait since LGM., Unatoč svojoj važnosti paleoproduktivnost (morskoga stupca) zapadnoga dijela tjesnaca Savu nije dobro istražena. Rezultati prethodnih istraživanja na obližnjemu jugozapadnom dijelu Sumbe i u tjesnacu Sumba možda nisu primjenjivi zbog oceanografske razlike. Stoga su foraminifere prikupljene u jezgre ST10 uporabljene u ocjeni njihove paleoproduktivnosti te rekonstrukciji dubine termokline. Stopa akumulacije i iznos nakupljanja (bentičkih) foraminifera uporabljeni su za procjenu paleoproduktivnosti, dok je relativna brojnost organizama termokline korištena za procjenu njezine dubine. Rezultati upućuju na povećanje paleoproduktivnosti tijekom posljednjega ledenog doba (~16 tis. god. pr. Kr.) i holocena (mlađe od ~11,65 tis. god. pr. Kr.) u zapadnome dijelu tjesnaca Savu. Dubina termokline bila je manja tijekom zadnjega ledenog doba te početkom oledbe, a zatim je porasla. Povećanje paleoproduktivnosti kod posljednjega ledenog maksimuma prouzročeno je pojavom sličnom australsko-indonezijskomu zimskom monsunu, koji karakterizira intenzivno obalno uzdizanje. Nadalje, holocensko povećanje paleoproduktivnosti povezano je s naglim porastom oborina koje su povećale kopneni/riječni donos. Varijabilnost dubine termokline u zapadnome dijelu tjesnaca Savu tako je povezana s promjenama dubine termokline u prostoru Jave (koji se uzdiže), odnosno plića termoklina vezana je uz zadnji ledeni maksimum te prateću deglacijaciju (prije ~11,65 tis. god. pr. Kr.). Dublja termoklina opažena je u holocenu (nakon ~11,65 tis. god. pr. Kr. ). Promjena dubine termokline upućuje na snažan utjecaj australsko-indonezijskoga monsuna na paleooceanografiju zapadnoga dijela tjesnaca Savu od zadnjega ledenog doba do danas.

A marine sediment core EW17-09 (03˚ 28’358” latitude and 96˚ 18’788” longitude, 870 m water depth, 390 cm core length) was retrieved from the western Sumatra, Simeulue sub-basin, Indonesia. Simeulue sub-basin are situated in eastern Indian Ocean, western part of Aceh Province, which is one of the outer islands in Indonesia. This sub-basin is influenced by adjacent lands in response to tectonic and climate dynamics. The dynamics of marine ecological conditions in the past is an urgent need for providing an analogy to the changes in the future conditions. In this study, the ecological conditions were examined by identifying the vertical distribution of planktonic foraminifera assemblages. This preliminary study demonstrated the presence of Globigerinoides ruber, Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, Globigerina calida calida, Globigerinoides elongates, Globigerinoides cyclostomus and Globigerinoides sacculiferus in the samples. The assemblages indicate warm water conditions prevailed in the Simeulue sub-basin during the deposition of the samples. However, subtle ecological changes might have occurred in response to the dynamic of thermocline layer. Cluster analysis of planktonic foraminifera abundance and diversity resulted in three groups showing different ecological conditions. Warm water conditions, high salinity, deeper thermocline with moderate sedimentation disturbance prevailed during the deposition of lower part of the core. Oligotropic water conditions with higher temperature, lower salinity, shallower thermocline layer, and moderate sedimentation disturbance predominated during the deposition of the middle part of the core. The paleooceanography conditions of the upper part of the core are comparable to the lower part. Nevertheless, there are a shoaling of the thermocline in the end of the period. These conditions may indicate an increase in upwelling fluctuations and may represent a change in the IOD-like mean state of the Indian Ocean.

Changes of the thermocline depth (DOT) at the Sumba Island offshore are not well-known compared to the DOT changes in the Timor Sea, the main exit passage of the Indonesian Through-flow (ITF). Planktonic foraminiferal assemblages in cores collected from the southwest Sumba offshore (ST08) and Sumba Strait (ST12, ST13, and ST14) were used as a tool to infer the DOT and paleoproductivity changes at the Sumba Island offshore. The DOT changes were indicated from the thermocline and mixed layer dwellers’ relative abundance while the paleoproductivity changes were indicated from the relative abundance of Neogloboquadrina dutertrei. This study suggests a contrast between the DOT pattern at the Sumba Island offshore and the DOT pattern in the Timor Sea during the Last Deglaciation–Holocene. The contrast DOT pattern indicated that the multi-millennial changes of the Australian-Indonesian monsoon (AIM) during the Last Deglaciation– Holocene were the main factors behind the DOT changes in this region while the effects of El Niño Southern Oscillation (ENSO) –like, Indian Ocean Dipole (IOD) –like, and ITF to DOT changes were minimal. Paleoproductivity enhancement at the Sumba Island offshore was not solely related to the monsoon-driven coastal upwelling intensification, which resulted in the DOT shoaling and eutrophic condition. The increase of nutrient availability in surface water due to river runoff increase and changes in the lifted water mass nature were also able to enhance productivity in this region., Područje ispitivanja nalazi se uz otok Sumba, a promjene dubine termokline (DOT) u ovoj regiji nisu dobro poznate u usporedbi s Timorskim morem. Zajednice planktonskih foraminifera korištene su za prepoznavanje DOT-a i promjene paleoproduktivnosti u jezgrama prikupljenim s jugozapadne Sumbe (ST08) i iz tjesnaca Sumba (ST12, ST13 i ST14). Ova studija sugerira da su tisućljetne promjene u režimu australsko-indonezijskoga monsuna (AIM) bile glavni čimbenik DOT promjena na jugozapadu Sumbe i tjesnaca Sumba nakon posljednje deglacijacije, što je stvorilo suprotne uvjete u odnosu na Timorsko more. Učinak poput južnih oscilacija El Niño (ENSO) i dipola Indijskoga oceana (IOD) sličnih DOT promjenama naznačen je samo oko kasnoga holocena, dok su promjene indonezijskoga protoka (ITF) utjecale samo na istočni tjesnac Sumba oko srednjega i kasnoga holocena. Produbljavanje termokline usko je povezano s poboljšanjem AIWM (AISM), El Niñom (La Niñom) i pozitivnim (negativnim) IOD-om. Poboljšanje paleoproduktivnosti nije bilo povezano samo s jačanjem DOT-a, već i s većom dostupnošću hranjivih sastojaka zbog povećanoga donosa slatke vode rijekama. Promjene u prirodi podignute vodene mase također su utjecale na promjene u paleoproduktivnosti.

Foraminifera distribution is one of the proxies used to reconstruct climatic conditions and paleoceanography. Specific species or groups of foraminifera can be associated with certain oceanographic parameters. As one of the entrances of Indonesia Through Flow (ITF), North Papua Waters has the role of channeling water masses from the Pacific Ocean to the Indonesian Waters. It is also influenced by global thermohaline circulation and ENSO. In this study, observations were made of changes in the distribution of foraminifera to reconstruct paleoclimate and paleoceanographic conditions in the North Papua Waters and their relation to global climate conditions. The analysis was performed on 246 cm core sediments with eight cm foraminifera observation intervals at sample depths 246-126 cm and four cm at sample depths of 126-0 cm. Pulleniatina spp., Neogloboquadrina spp., and Globorotalia spp., are used for radiocarbon dating. Planktonic abundant species of foraminifera are Pulleniatina obliqueloculata, Neogloboquadrina dutertrei, Globorotalia menardii, Globigerinoides ruber, Globigerinoides trilobus, and the benthonic are Melonis pompilideus, Pullenia bulloides, Oolina sp., Planulina bradyii, Oridorsalis umbonatus, Cibicides subhaidingerii, Eggrela bradyii, Planulina wuelestroffi, and Quinqueloculina spp.,. Division according to cluster analysis can show the difference between Holocene and Pleistocene, which is then more detailed divided into 17 clusters. Based on biozonation there are some events that can be observed: climate variability since Late Pleistocene, record Pleistocene-Holocene boundary based on the significant variability of foraminifera distribution, and records some of the global climate events such as Last Glacial Maximum (~19-17 kyr), Younger Dryas (~11-9 kyr), and 8,2K event.

On 22 December 2018, volcanic activity of Anak Krakatau, Indonesia, triggered a tsunami that caused more than 437 casualties on surrounding coastlines. Soon after the event, before the physical evidence of the tsunami disappeared, a postevent field survey was carried out. Measurements of tsunami inundation and impact are important to better model and understand the tsunami triggering processes to support future tsunami mitigation efforts. The impacted area on the western coast of Banten, Java Island, was surveyed to acquire tsunami inundation and run-up height data, together with field characteristics of the tsunami deposits. Data were acquired at 36 locations along three transects of tsunami deposits. From these, the maximum tsunami run-up height (up to 13 m) in the surveyed locations was identified on the southern part of the Banten Coast in the Tanjung Lesung area, an area located to the south of Anak Krakatau Volcano. The tsunami deposits were relatively thin along the transect, including a fining upward sequence without any clear evidence of fresh volcanic material, in disagreement with other reported volcano-induced tsunami deposits. Characteristics of the 2018 Anak Krakatau tsunami deposits are more similar to earthquake-induced tsunami deposits, hence complicating the paleotsunami reconstruction in Sunda Strait, where tsunami mechanisms are from both volcano and earthquakes along the Sunda subduction zone.

The Simeulue sub-basin is situated off north-western Sumatra between the outer arc and the mainlands. The sediment and geochemical element characteristics of basins are the important sedimentology variables to recognize the process of sediment deposition. However, the characteristics of the sediment and the geochemical elements in the Simeulue subbasin have not been well explained. This study aims to investigate the textural and geochemical elements characteristics of marine sediments and the distribution of these two variables to determine the sedimentary facies in the Simeulue sub-basin. Samples were taken from various depths in the sub-basin and collected during the 2017 Expedition of “Widya Nusantara” by using the “Baruna Jaya VIII” Research Vessel. The grain size trend analysis showed that the middle part of the basin was dominated by mud, while the edge of the basin near the island (mainland) was mostly dominated by coarser sediments. A geochemical element analysis was performed on each sample to observe the origin of the sediments. The results of these two analyses were subjected to multivariate statistics. This approach was selected because it is appropriate for determining the sedimentary facies and the depositional environments. Based on the multivariate analysis, the sedimentary facies in the Simeulue sub-basin was divided into five facies with similar sediment characteristics and depositional environments. These facies were deposited in the environment with low to medium energy., Podbazen Simeulue nalazi se uz sjeverozapadni rub Sumatre, između vanjskoga luka i kopna. Taložna i geokemijska obilježja bazena važne su sedimentološke varijable u prepoznavanju taložnih procesa. Te varijable u analiziranome prostoru do sada nisu bile dobro proučene. Stoga su istražene u ovome radu te je napravljena njihova razdioba kako bi se utvrdili taložni facijesi u tome podbazenu. Uzorci su uzeti na različitim dubinama tijekom ekspedicije „Widya Nusantara” 2017. godine, obavljene istraživačkim brodom Baruna Jaya VIII. Analiza trenda veličine zrna pokazala je kako u srednjemu dijelu bazena prevladava mulj, dok je na rubovima, u blizini kopna (otoka Sumatre) istaložen krupniji detritus. Geokemijska analiza načinjena je na svakome pojedinačnom uzorku s ciljem određivanja njegova podrijetla. Rezultati su naknadno analizirani multivarijantnom statistikom koja je odabrana kao najprimjereniji alat za određivanje taložnih facijesa i okoliša. Temeljem takve analize podbazen Simeulue podijeljen je u pet taložnih facijesa sa sličnim svojstvima taložina. Taložni okoliš bio je sličan, niskoenergijski do srednjoenergijski.

Southeast Asian peatlands, along with their various important ecosystem services, are mainly distributed in the coastal areas of Sumatra and Borneo. These ecosystems are threatened by coastal development, global warming and sea level rise (SLR). Despite receiving growing attention for their biodiversity and as massive carbon stores, there is still a lack of knowledge on how they initiated and evolved over time, and how they responded to past environmental change, that is, precipitation, sea level and early anthropogenic activities. To improve our understanding thereof, we conducted multi-proxy paleoecological studies in the Kampar Peninsula and Katingan peatlands in the coastal area of Riau and Central Kalimantan, Indonesia. The results indicate that the initiation timing and environment of both peatlands are very distinct, suggesting that peat could form under various vegetation as soon as there is sufficient moisture to limit organic matter decomposition. The past dynamics of both peatlands were mainly attributable to natural drivers, while anthropogenic activities were hardly relevant. Changes in precipitation and sea level led to shifts in peat swamp forest vegetation, peat accumulation rates and fire regimes at both sites. We infer that the simultaneous occurrence of El Niño-Southern Oscillation (ENSO) events and SLR resulted in synergistic effects which led to the occurrence of severe fires in a pristine coastal peatland ecosystem; however, it did not interrupt peat accretion. In the future, SLR, combined with the projected increase in frequency and intensity of ENSO, can potentially amplify the negative effects of anthropogenic peatland fires. This prospectively stimulates massive carbon release, thus could, in turn, contribute to worsening the global climate crisis especially once an as yet unknown threshold is crossed and peat accretion is halted, that is, peatlands lose their carbon sink function. Given the current rapid SLR, coastal peatland managements should start develop fire risk reduction or mitigation strategies.

Perairan Indonesia, salah satunya Perairan Utara Papua, memiliki peran penting dalam sirkulasi global, yaitu sebagai salah satu pintu masuk Arlindo yang mengalir dari Samudra Pasifik menuju Samudra Hindia. Rekonstruksi perubahan input sedimen sejak ~19 ribu tahun lalu dilakukan pada sampel sedimen laut dalam (OS-07) sepanjang 246 cm yang diambil dari kedalaman 4327 m di Perairan Utara Papua, Samudra Pasifik. Sampel diambil pada Ekspedisi Nusa Manggala 2018 dengan menggunakan penginti gravitasi pada Kapal Riset Baruna Jaya VIII. Rekonstruksi input sedimen dilakukan berdasarkan data kandungan unsur kimia Fe, Ti, dan Rb dan normalisasi unsur darat terhadap unsur laut. Input sedimentasi yang tinggi ditunjukkan pada Plesitosen Akhir (~19.5-16 ribu tahun BP) yang kemudian menurun pada pada ~12.5-10 ribu tahun BP yang diinterpretasikan berkaitan dengan peristiwa Younger Dryas . Pada Kala Holosen, input sedimen yang tinggi ditunjukkan pada ~8-5 ribu tahun BP dan ~2-0,5 ribu tahun BP, dan input sedimen yang rendah pada ~11-8 ribu tahun BP dan ~5-2 ribu tahun BP.

AN OVERVIEW OF DIATOM AND ITS APPLICATIONS ON THE GEOSCIENCE AREA. Diatoms have been being studied in many countries. Diatoms provide a valuable and well-understood means on biomonitoring – one of which is focused on the base of the aquatic foodweb and highly representative of water quality. They are found in most aquatic environments and the sys tematic and taxonomic investigations of modern and fossil diatoms have been supported by numerous stud ies of distributional ecology. Diatom systematics, taxonomy and ecology indeed offer a wide scope of applications - from water quality to environmental monitoring and biostratigraphy as well as on geoscience area. The application of diatom analysis in determining whether drowning was the cause of death has proven to be a valuable tool in forensic science. Furthermore, diatoms can provide a record of environmental conditions because their relationship to water quality and aquatic habitat has been already known, and the diatom cell wall, which is silicified to form a frustule, is well-preserved, easily detectable and occurs in high numbers in sediment and water. However, this should not be limited to simply make an inventory of data: thoughtful ecology and paleo-ecology will assist in predicting the environmental impact of pollution and climate changes.

Previous studies suggested the multi-millennial scale changes of Australian-Indonesian monsoon (AIM) rainfall, but little is known about their mechanism. Here, AIM rainfall changes since the Last Deglaciation (~18 ka BP) are inferred from geochemical elemental ratios (terrigenous input) and palynological proxies (pollen and spores). Pollen and spores indicate drier Last Deglaciation (before ~11 ka BP) and wetter Holocene climates (after ~11 ka BP). Terrigenous input proxies infer three drier periods (i.e., before ~17, ~15&ndash, 13.5, and 7&ndash, 3 ka BP) and three wetter periods (i.e., ~17&ndash, 15, ~13.5&ndash, 7, and after ~3 ka BP) which represent the Australian-Indonesian summer monsoon (AISM) rainfall changes. Pollen and spores were highly responsive to temperature changes and showed less sensitivity to rainfall changes due to their wider source area, indicating their incompatibility as rainfall proxy. During the Last Deglaciation, AISM rainfall responded to high latitude climatic events related to the latitudinal shifts of the austral summer ITCZ. Sea level rise, solar activity, and orbitally-induced insolation were most likely the primary driver of AISM rainfall changes during the Holocene, but the driving mechanisms behind the latitudinal shifts of the austral summer ITCZ during this period are not yet understood.

We report results of field surveys and numerical modeling of the tsunami generated by the Anak Krakatau volcano eruption on 22 December 2018. We conducted two sets of field surveys of the coastal areas destroyed by the Anak Krakatau tsunami in 26-30 December 2018 and 4-10 January 2020. Field surveys provided information about the maximum tsunami height as well as the most damaged area. The maximum tsunami height was up to 13 m. Most locations registered a wave height of 3-4 m. Tsunami inundation was limited to approximately 100 m. For modeling, we considered 12 source models and conducted numerical modeling. The scenarios have source dimensions of 1.5–4 km and initial tsunami amplitudes of 10–200 m. By comparing observed and simulated waveforms, we constrained the tsunami source dimension and initial amplitude in the ranges of 1.5–2.5 km and 100–150 m, respectively. The best source model involves potential energy of 7.14 × 1013–1.05 × 1014 J which is equivalent to an earthquake of magnitude 6.0–6.1.

Copyright © The Author(s) 2020. The 22 December 2018 Anak Karakatau tsunami in Indonesia was a rare event in that few instrumental records existed of tsunamis generated by volcanic sources before this event. The tsunami, which left a death toll of 437, is of global importance as it provides opportunities to develop knowledge on generation, propagation and coastal effects of volcanic tsunamis. Here, we report results of field surveys along the coast of the Sunda Strait, Indonesia to study tsunami wave heights and coastal damage. We surveyed 29 locations and measured ranges of tsunami runup from 0.9 to 5.2 m, tsunami heights from 1.4 to 6.3 m, flow depths from 0.2 m to 3.0 m and inundation distances from 18 to 212 m. The largest tsunami heights and concentration of damage and fatalities occurred on the western shore of Java from Tanjung Lesung to Sumur. The largest cluster of fatalities occurred at Tanjung Lesung, where more than 50 people died while attending an outdoor music being held at the shoreline. The tsunami runup and tsunami height in Tanjung Lesung were 4.0 and 2.9–3.8 m, respectively. We believe this tragedy could have been avoided if the event organizers were more aware of the hazard posed by the Anak Krakatau volcano, as it had been actively erupting for several months prior to the tsunami, and simply moved the concert stage 100 m inland. Many of the locations surveyed demonstrated a similar pattern where the majority of casualties and destruction occurred within 100 m of the coast; in several locations, lives were saved where buildings were located at least this distance inland. The significant damage and numerous deaths which occurred in Sumur, despite the moderate tsunami height of 2.3–2.5 m, can be attributed to the extremely low-lying coastal land there. Flow depth in Sumur was 0.9–2.0 m. During our field surveys, nearly one year after the event, we noted that some of the damaged buildings were being rebuilt in the same locations just 10–30 m from the shoreline. We question this practice since the new buildings could be at the same tsunami risk as those damaged in the 2018 event. Royal Society, United Kingdom (grant number CHL\R1\180173).

MARINE SEDIMENT AS PROXY TO DETERMINE CLIMATE DYNAMICS IN THE PAST. Studying the dynamics of climate change in the past is important and necessary, because it can serve as a basis for understanding the modern climate and the causes of its variations and changes. Evidence of past climatic conditions is usually archived on traces in nature that provide a proxy of past climatic conditions that we can explore. One of the major sources of proxy data for paleoclimate reconstruction is marine sediment. Microfossils usually used for quantitative proxy is foraminifer, diatom, pollen and etc. For the purposes of paleoclimate, the most important material is foraminifera. The paleoclimate results from the remains of carbonate and silica organisms have been generated from four types of analyzes: (a) oxygen isotope composition, especially calcium carbonate in foraminifer test (b) quantitative interpretation of species and its spatial variation through (c) the ratio of Mg / Ca to the foram test, which is related to temperature, and (d) the morphological variation in certain species resulting from environmental factors.

A study of sediment dynamics has been conducted on the Tarakan sub-basin, North Kalimantan, Indonesia using multivariate analysis. Multivariate statistical techniques can be used to determine sediment with similar characteristics and be a good proxy to recognize sedimentary facies and depositional environment. These methods have been applied to characterize the sedimentary facies at Tarakan sub-basin. A total of 23 samples were taken from several locations on the different depths of 56–2554 m that represent varieties of environment. The study is interpreted using compositional data analysis associated with a grain size trend analysis (GSTA), principal component analysis (PCA), and cluster analysis (CA). The GSTA value showed the dominance of poorly sorted silt indicating that the sediment is mostly deposited in low-energy depositional. The CA and the PCA determined three distinct sedimentary facies: shelf facies, upper bathyal facies, and lower bathyal facies. The facies were grouped as similar se...

A study of characteristics and distribution of sediment along Waikelo Beach, Sumba, Nusa Tenggara Timur (NTT), Indonesia has been conducted using grain size train analysis. Grain size train analysi...

Sedimen inti EW17-08 terletak pada tepi baratlaut Paparan Sunda. Pengendapan sedimen pada wilayah tersebut berhubungan dengan perubahan kenaikan muka air laut yang terjadi pada paparan Sunda. Penelitian ini merupakan studi pendahuluan yang bertujuan untuk mengetahui karakterstik sedimen berdasarkan analisis tren ukuran butir pada periode transisi Holosen - Pleistosen. Sedimen inti EW17-08 diambil pada Ekspedisi Widya Nusantara menggunakan Kapal Riset Baruna Jaya VIII. Karakteristik sedimen Holosen dan Pleistosen dapat dibedakan dari nilai mean, sorting, skewness dan kurtosis. Batas Holosen – Pleistosen ditentukan berdasarkan kemunculan pertama dari Bolliela Adamsi pada kedalaman 161 cm. Fasies sedimen dalam inti tersebut dibedakan menjadi dua fasies, fasies I berumur Pleistosen Akhir dengan komposisi sedimen berupa perselingan lanau sedang-pasir sangat halus. Fasies II dengan komposisi sedimen berupa lanau kasar dan berumur Holosen. Hasil studi pendahulan ini diharapkan dapat digunakan untuk mengetahui perubahan lingkungan yang terjadi selama Pleistosen – Holosen.

Sejarah tsunami modern di Pulau Simeulue tercatat telah terjadi tahun 1861, 1907, 2004 dan 2005. Teluk Busong yang terletak di pesisir barat Pulau Simeulue menjadi salah satu wilayah terdampak. Penelitian bertujuan mengidentifikasi dan mengetahui karakteristik endapan tsunami tersebut di Teluk Busong. Metode yang digunakan adalah analisis granulometri, paleontologi, analisis loss on ignition, geokimia XRF, dan FTIR pada sampel inti sedimen. Endapan tsunami pada daerah penelitian memiliki sortasi buruk dengan ukuran butir pasir sedang – kasar yang terdistribusi bimodal. Analisis LOI menunjukkan bahwa endapan tsunami memiliki kandungan material organik dan karbonat yang tinggi, menunjukkan pengaruh darat dan laut. Pengaruh laut ditunjukkan kandungan material karbonat yang signifikan, terkonfirmasi dari keberadaan cangkang foraminifera. Secara geokimia, terdapat anomali kelimpahan unsur pada endapan tsunami dibanding dengan endapan nontsunami. Unsur kimia Zr, Sr, Fe, Ti, K, Cr, dan Rb menunjukkan anomali pada endapan tsunami yaitu cenderung naik, terutama Sr yang menjadi penciri pengaruh laut. Berdasarkan analisis FTIR, ditemukan mineral kuarsa, kalsit, feldspar, aragonit, monmorilonit, paligorskit, dan magnetit pada endapan tsunami yang menunjukkan asosiasi mineral asal darat dan laut.

This research was conducted in the Sumba Strait, southwest of Sumba East Nusa Tenggara. The Purpose of this study is to determine the depositional facies characteristics of the Quaternary deep sediment. The sample was taken at a depth of 1858 m by gravity core in board of RV Baruna Jaya VII by the geology team of Ekspedisi Widya Nusantara LIPI 2016. The length of the sample was 246 cm. Sedimentology analysis was conducted to measure grain size distribution, organic material and carbonate content in the core. The characteristics of the sediment were dominated by coarse silt, poorly sorted, symmetrical skewness and mesokurtic kurtosis. Generally, the percentage of carbon and carbonate is 20.09% carbon and 9.67% carbonate; it shows that grain size is very influential on organic material in the sediment. The finer the grain of sediment the higher the organic material, which in the sediment results from the grain size analysis indicates the dominant grain size of the fine (Coarse silt).

Simeulue Island was located in an active tectonic zone that causes earthquakes followed by tsunamis. This research was conducted to get a detail explanation of tsunami deposits found in eastern S i meulue Island. The methods used in this study include granulometry analysis, Loss on Ignition (LOI ) , X-ray Fluorescenc e (XRF), and pal y nology. Based on anal yzed , it was known that tsunami deposits in the studied area have non-uniform grain size characteristics and are dominated by gravel to boulder. The results of the LOI analysis show that the concentration of organic and carbonate material was very high, which is thought to be caused by a mixture of marine and terrestrial materials due to a tsunami . XRF analysis showed high content of Ca and Sr which indicated the influence of seawater on sediments . The pa ly nological analysis showed that taxa from the lowlands and mangroves palynofacies dominate the presence of pollen, indicating that the possibility of depositional environments is the area around the mangrove coast. The presence of high lowland taxa is thought to originate from the tsunami backwash that brought material from the lowlands to the surrounding coast. Pulau Simeulue terletak pada zona tektonik aktif yang menyebabkan terjadinya banyak gempa yang diikuti tsunami. Penelitian ini bertujuan untuk mengetahui karakteristik detil endapan tsunami yang terdapat di Pulau Simeulue bagian timur. Metode yang digunakan dalam penelitian ini meliputi analisis palinologi, granulometri, Loss on Ignition (LOI), dan XRay Flourescence (XRF). Berdasarkan analisis tersebut diketahui bahwa endapan tsunami di daerah penelitian memiliki karakteristik ukuran butir yang tidak seragam dan didominasi oleh ukuran butir kerikil hingga bongkah. Hasil analisis LOI menunjukkan konsentrasi material organik dan karbonat sangat tinggi, yang diduga disebabkan oleh percampuran material asal laut dan darat karena tsunami. Analisis XRF menunjukkan tingginya kandungan unsur Ca dan Sr yang mengindikasikan adanya pengaruh air laut pada endapan. Analisis palinologi menunjukkan taksa dari palinofasies dataran rendah dan mangrove mendominasi kehadiran polen. Hal ini mengindikasikan bahwa kemungkinan lingkungan pengendapan adalah area sekitar pantai mangrove. Kehadiran taksa dataran rendah yang tinggi diduga berasal dari gelombang balik tsunami yang membawa material dari dataran rendah ke sekitar pantai tersebut.

A significant development of open science movement has been witnessed in the last five years. This could bring a fresh start to Indonesian academia. The objective of this paper is to showcase the advancement of open science concept and implementation that can be adopted to increase impact. We did a literature review on peer-reviewed papers, websites of funding agency, open science blogs, and threads on Twitter.We believe the values of research output are not limited to a paper in a high reputation journal. Data is now considered as separate output, as well as, data management protocols, and laboratory notebooks. Publishing research results as a preprint is also used to disseminate findings as rapid and as fast as possible. Post publication peer-review is also added to the reviewing system to add openness, transparency, and objectivity. It offers credit to the reviewers. We also see the growth of impact indicators as the results of San Francisco Declaration on Research Assessment (DORA) statutory. More initiatives and technologies have been introduced to make science more open, transparent, and inclusive.With so many developments have been made, therefore it’s not wise for Indonesian academia to rely themselves only to the old perception of research outputs and impact indicators.

Analysis of foraminifera in geology,usually being used to find the age of rocks/ sediments and depositional environment. In this study, recent foraminifera was used not only to determinethe sedimentary environment,but also to estimate the ecological condition of the water through a statistical approach.Analysis was performed quantitatively in 10 surface seabed sediment samples in Weda Bay North Maluku. The analysis includes dominance (Sympson Index), diversity and evenness (Shannon Index), and the ratio of planktonic -benthic. The results were shown in the plotting diagram of M-R-T (Miliolid-Rotalid-Textularid) to determine the depositional environment. Quantitative analysis was performed using Past software (paleontological version Statistic 1:29).The analysis result showed there was no domination of certain taxon with a moderate degree of evenness and stable communities and considerably a moderate diversity. The results of this analysis indicated that research area had a stable water conditions with the optimum level of carbonate content, oxygen supply, salinity, and temperature. The ratio of planktonic and benthic indicate the relative depth, which was deeper the water increased the percentage of planktonic foraminifera. Based on M-R-T diagram showed the distribution of sediment deposited on exposed carbonate (carbonate platform) environment with normal saline.

Study of beaches sediment characteristics were conducted on three beaches on Sumba Island, East Nusa Tenggara.The research is a part of Widya Nusantara Expedition which conducted by using Research Vessel of Baruna Jaya VIII. The aim of this study is to determine the characteristics of coastal deposits through the observation of grain size by using the grain size trend analysis approach (Grain Size Trend Analysis, commonly abbreviated as GSTA) and geochemical analysis. A total of 36 samples were taken on each coast representing high tide, transition and low tide along the coast. A grain size analysis was performed using a Malvern Mastersizer 2000 that was processed with Gradistat 4.0 software. Geochemical analysis was carried out using X-ray fluorescence spectrometry (XRF). The distribution of beach sediments is dominated by moderate sand - coarse sand and differences on content of geochemical elements (Ca, Sr, Fe, K, and Ti). The coastal conditions that are connected to the Indian Ocean (B1) have different characteristics from the beach that connected to the Sumba strait (B5 and B7). GSTA analysis showed sediment of Laboya Beach finer than sediment on Waikelo and Melolo Beach. Geochemical elements on Laboya Beach indicates different values than others. It indicates there are differences in the provenance and composition of sediment on the all three beaches. The supply of coastal deposits on these three beaches is influenced by the mechanism of precipitation of the walls and the processes of waves and rivers.Keywords: distribution, sediment, grainsize, geochemical, XRF, beach sediment.

Sumba merupakan salah satu pulau terluar Indonesia yang terletak di bumi bagian selatan dan berbatasan dengan Samudra Indonesia. Distribusi polen pada sedimen permukaan di Perairan Sumba dilakukan untuk membantu interpretasi efek sedimentasi yang terjadi di daerah fluvial dan laut serta perubahan tumbuhan terestrial. Penelitian ini merupakan bagian dari Ekspedisi Widya Nusantara 2016 yang dilaksanakan pada tanggal 4 – 26 Agustus 2016 menggunakan Kapal Riset Baruna Jaya VIII. Tiga belas sampel sedimen permukaan dianalisis menggunakan metode asetolisis dan swirling . Spektrum polen menunjukkan hubungan antara distribusi polen yang mengendap di sedimen laut dan transportasinya dari daratan. Sebaran polen yang banyak terakumulasi di bagian barat Pulau Sumba menunjukkan adanya pengaruh fluvial dan jarak dari pantai dan kedalaman air. Hasil uji korelasi antara distribusi polen dengan kedalaman dan besar butir (rata-rata dan persentase mud) menunjukkan hubungan yang cukup kuat (r=0,465; r=0,374 dan r=0,443). Meskipun dengan rata-rata tingkat keanekaragaman tumbuhan termasuk dalam kategori rendah (indeks 1,07), distribusi polen dalam sedimen permukaan laut merefleksikan vegetasi lokal di daratan Pulau Sumba. Polen yang paling mendominasi berasal dari Famili Poaceae. Studi ini menjelaskan bahwa rekaman polen dari inti sedimen laut Perairan Sumba mempunyai potensi menjadi alat rekonstruksi perubahan vegetasi di daratan sekitarnya dalam studi variabilitas iklim masa lalu dan masa yang akan datang. Sumba, one of the outer Indonesian island, is located in the southern hemisphere and bordered by the Indonesian Ocean. The distribution of pollen in marine sediments offshore the Sumba Waters has been investigated to help interpret the sedimentation effect on fluvial inputs, marine and terrestrial vegetation changes. The research is a part of Expedition of Widya Nusantara 2016 which was conducted on 4 - 26 August 2016 using Baruna Jaya VIII research vessel. Thirteen surface sediment samples were analyzed by acetolyisis method and swirling. Pollen spectra illustrate the relationships between pollen distribution in the sampled marine sediments and their transport from the vegetation onshore. The pollen distribution that accumulated a lot in western part of Sumba island were linked to fluvial inputs and controlled by the distance from the coast and water depth. Correlation test between the distribution of pollen and water depth as well as grain size (mean and mud percentage) showed moderate correlation (r=0.465; r=0.374 and r=0.443, respectively). Although the average of vegetation diversity index is in low category (index of 1.07), the pollen distribution percentage in these marine surface sediment samples reflects the local vegetation from the nearby onshore of Sumba island. The most dominant pollen comes from Family Poaceae. This study demonstrates that pollen records from marine surface sediment in the Sumba Waters have the potential tool to reconstruct palaeovegetation on the adjacent continent for the past and future climate variability study at these area.

Penelitian ini merupakan bagian dari Ekspedisi Widya Nusantara 2016 yang bertujuan untuk merekonstruksi dinamika iklim dengan memperhatikan kondisi keanekaragaman morfologi polen, spora dan keanekaragaman flora sekitar perairan Selat Sumba pada Kala Holosen. Sedimen diambil menggunakan penginti gravitasi pada Kapal Riset Baruna Jaya VIII pada kedalaman kolom air 1283 m dengan panjang inti 243 cm. Kedalaman yang diamati yakni 0-102 cm dengan interval penyamplingan adalah 5 cm, sehingga diperoleh 22 sub-sampel. Jenis sedimen yang dominan adalah lanau sedangkan pasir hanya mendominasi bagian permukaan. Berdasarkan hasil analisis kuantitatif palinologi, lapisan dibagi menjadi empat zona dan untuk mengetahui umur dari tiap lapisan sedimen digunakan datum Foraminifera Globigerinella calida calida. Zona I dengan perkiraan umur 5662-7550 tahun yang lalu memiliki karakteristik, jenis Arboreal Pollen (AP) yang lebih dominan yakni Cupressaceae, sedangkan jenis spora yang dominan adalah Polypodiaceae dan Acrostichum aureum. Zona ini diintepretasikan beriklim panas dan basah, dengan nilai Pollen Marine Index (PMI) 100 dan indeks keanekaragaman adalah 0,35. Zona II berumur 4530-5662 tahun yang lalu dengan kehadiran Arboreal Pollen (AP) yang lebih dominan adalah Casuarinaceae dan spora Polypodiaceae, sehingga diintepretasikan iklimnya adalah panas dan basah, PMI = 105 dan Indeks keanekaragaman 1,56. Zona III berumur 2265-4530 tahun terdapat Arboreal Pollen (AP) yakni Anonaceae 43,75 % dan Spora yakni Polypodiaceae 33 %, sehingga diintepretasikan beriklim panas dan basah, PMI= 118 serta Indeks keanekaragaman 2. Zona IV adalah lapisan paling muda berumur 2265-sekarang memiliki persentase Arboreal Pollen (AP) yang lebih dominan yakni Anonaceae sebanyak 44% dan adanya peningkatan kehadiran spora yakni taksa Acrostichum aureum sebanyak 41,2 %, PMI = 128,25 dan memiliki Indeks keanekaragaman 1. This research is part of Widya Nusantara Expedition 2016 aiming to reconstruct the dynamics of the climate by considering the condition of morphology of pollen, spore and the diversity of flora around the waters of the Sumba Strait in the time of Holocene. The sediment was taken using gravity corer on Research Vessel of Baruna Jaya VIII at a water column depth of 1283 m with a core length of 243 cm. The depth was observed at 0-102 cm and the sampling interval of 5 cm, so 22 sub-samples were obtained. The dominant type of sediment was silt and sand dominates on the surface. Foraminifera Globigerinella calida calida is used as a datum to determine relative age. Based on the results of the analysis, the layers are divided into four zones. Zone I with an estimated age of 5662-7550 years ago has a more dominant Arboreal Pollen (AP) type characteristic, namely Cupressaceae, while the dominant spores are Polypodiaceae and Acrostichum aureum . This zone is interpreted as a hot and wet climate, with a Pollen Marine Index (PMI) 100 and a diversity index of 0.35. Zone II was 4530-5662 years ago with the more dominant Arboreal Pollen (AP) presence being Casuarinaceae and Polypodiaceae spores, so the interpreted climate was hot and wet, PMI = 105 and the Diversity Index 1.56. Zone III aged 2265-4530 years. There are Arboreal Pollen (AP) i.e. Anonaceae 43.75% and Spores i.e. Polypodiaceae 33%, so it is interpreted as hot and wet climate, PMI = 118 and Diversity Index 2. Zone IV is the youngest layer of 2265 – now. It has the most dominant percentage of Arboreal Pollen (AP), Anonaceae as much as 44% and an increase in the presence of spores i.e. Acrostichum aureum taxes as much as 41.2%, PMI = 128.25 and has a Diversity Index of 1.

Marine geological survey of Ekspedisi Widya Nusantara (EWIN) LIPI 2016 was conducted by using RV Baruna Jaya VIII in the Sumba Waters from 4 to 26 August 2016. One of the aim of this survey is to understand the sea floor surface sediment characteristics and its influence to the benthic foraminifera distribution. Seven sediment samples were collected from sea floor surface in Sumba Strait, at the different location and depth using grabbing method with box corer. The samples have analyzed for the foraminifera content, sediment grain size, organic matter and carbonate content, and chemical element by XRF method. The living benthic foraminifera distribution increase to the east of the research area, which have higher content of the organic material and Fe, Rb, Zr, Zn and Sr elements in the sediment. The benthic foraminifera distribution most abundance founded at the depth of 800-1000 m with sediment types are sandy coarse silt to sandy very coarse silt.Keywords: Benthic foraminifera, distribution, sea floor sediment, Sumba Strait. DOI: 10.33332/jgsm.2019.v20.1.17-26

An integrated study of sediment distribution was conducted in Weda Bay, Northern Maluku to provide general information on transportation and deposition process based on sediment grain size distribution. The study was conducted during the Weda Bay Expedition using the “Baruna Jaya VII” research vessel in March 13th –22th 2013. Sieving method (granulometric) was used to analyze the grain size. The results indicated that in general the pattern of sea floor sediment distribution was dominated by clay – sand grain-sized. The current speed influenced the sediment transport, deposition, and distribution. Larger fractions of sediment were quickly settled on the sea floor due to stronger currents around Southern area (Widi islands), meanwhile the lesser fractions of the transported away into other places with weaker currents conditions. Keywords: current, the Weda Bay expedition, granulometric, grain size, sediment distribution