Many islands of the eastern Indonesian Archipelago exhibit Late Cenozoic sequences of coral reef terraces. In SE Sulawesi, on the Tukang Besi and Buton archipelagos, we identified 23 islands bearing such sequences. Remote sensing imagery and field mapping combined to U/Th and 14 C dating enable to establish a chronologic framework of the reef terrace sequences from Wangi-Wangi, Buton as well as on the neighbouring, smaller islands of Ular, Siumpu and Kadatua. We identified the terraces from the last interglacial maximum (MIS 5e) at elevations lower than 20 m except on W Kadatua where it is raised at 34 ± 5 m. Such elevations yield low to moderate Upper Pleistocene uplift rates (<0.3 mm yr À1). On SE Buton Island, a sequence culminates at 650 m and includes at least 40 undated strandlines. Next to this exceptional sequence, on the Sampolawa Peninsula, 18 strandlines culminate at 430 m. Dated samples at the base of this sequence (<40 m) yield mean Middle Pleistocene uplift rates of 0.14 ± 0.09 mm yr À1. Extrapolation of these uplift rates compared to the geological setting suggests that the sequences of the Sampolawa Peninsula provide a record of sea-level high-stands for the last 3.8 ± 0.6 Ma. The sequences on SE Buton Island therefore constitute the best preserved long-lasting geomorphic record of Plio-Quaternary sea-level stands worldwide.
The quality of universities, especially study programs in Indonesia is measured based on accreditation conducted by BAN PT. According to BAN PT the quality is measured based on 7 main standards, one of them is Student and Graduate. One of the problems that still be the subject of discussion related to student failure is about the students who graduated not on time. Students graduating not on time are students who can not complete their studies in accordance with the provisions of time given. The existence of a graduate student is not timely of course cause problems and potentially drop out that affect the quality of education and accreditation. A system that predicts students' graduation is required by evaluating their learning outcomes. The timeliness of graduating students can be done with data mining techniques to find graduation patterns of students who have graduated which then used as a basis to predict students' graduation in the next year. This study showed that Naïve Bayes was able to classify the correct data testing on average by 86.16% and 13.84% error. In addition, other information obtained from the data testing used that the students who entered from the PMDK Pass graduated on time as much as 40%, other paths graduated on time by 26.7%, and pass filter exam on time 13.3%.
This study aims to correlate fixed carbon content using proximate analysis and calorific value analysis of the South Sulawesi Mallawa Formation coal. The study was conducted at two locations, namely in the Massenrengpulu Region of Bone Regency and Pujananting Region in Barru Regency. The research method used is the collection of field data each using the channel sampling method (ply by ply), which represents the lower layer, middle layer and upper layer. Then a proximate analysis is performed to obtain a fixed carbon content and an analysis of the calorific value. The results of the analysis show that, coal in the Pujananting area shows a correlation between the percentage of fixed carbon and the calorific value has a very good correlation with the linear regression value of 0.9994. Similar to the Mallawa Formation coal in the Massenrengpulu area, the correlation of fixed carbon content and calorific value shows a very good correlation with a linear regression value of 0.9998. An increase in the percentage of fixed carbon in coal will be followed by an increase of calorific value. This increasingly shows a very strong correlation between fixed carbon content and calorific value in coal.
The Mallawa Coal Formation in general, has a high sulfur content even though the calorific value is quite high. Deposition environment will affect the sulfur content in coal. This study aims to determine the relationship of sulfur content to the percentage of pyrite mineral content in coal by microscopy. The research method used is field data collection, each using the channel sampling method (ply by ply) in Pujananting Barru Regency and Massenrengpulu Bone regency. Then a proximate and petrographic analysis was carried out to obtain sulfur content, and the percentage of pyrite in coal. The analysis shows that coal in the Pujananting area shows no relationship correlation between total sulfur content in coal and the percentage of pyrite minerals, so it can be concluded that sulfur in Pujananting coal is organic sulfur, which is formed together with the formation of coal starting during the peat process. While Massenrengpulu coal shows a correlation and relationship between the increase in sulfur content and the increase in the percentage of pyrite minerals, it can be concluded that the sulfur content in Massenrengpulu coal is derived from pyritic sulfur, which is strongly influenced by the depositional environment where the coal is formed.
In 2013 there has been 34 incidents of landslides which cut the roads linking between Gowa and Sinjai off. The purpose of this study was to determine the effect on the stage of weathering of landslide in the study area. Methods used in this study are field survey, petrographic analysis, XRD analysis and shear strength testing of rock. Field survey results indicates that the area is dominated by tuffs that are partly volcanic breccia and lava. Petrographic analysis, showing the dominant composition of tuff with volcanic glass, bitownite, pyroxene and opaque minerals, and XRD analysis results indicate weathering tuffs that have experienced high and completely weathered contain smectite and halloysite clay types, and insitu shear strength test results indicate a strong shift to the lower tuff with high stage of weathering. Keywords: Susceptability to landslides, the stage of weathering, halloysite and smectite, shear strength, roads of Malino–Manipi
Intensive cropping in the tropical region always becomes one of important driving forces of soil degradation. The primary aim of this study is to analyze the states and the dynamics of soil physicochemical properties to evaluate soil degradation in the tropical region a high rainfall on agricultural areas in South Sulawesi. A number of soil characteristics were analyzed for physical and chemical properties, and clay minerals with X-ray diffractometer. The degree of soil degradation is determined using Wischmeier and Smith equation. This study reveals that mean annual precipitation in 1979-2016 ranged from 1853.15 to 2981.30 mm/year. For land used for paddy field, palm oil, cacao and coffee plantation, the texture dominated with silt loam-clay loam, cation exchange capacity was 18.63-26.32 cmol+ kg-1, 0.98-2.91% of C-organic, 32-55% of base saturation, 0.1-3.5 cm h-1 of permeability, soil clay minerals were montmorillonite-kaolinite-halloysite, and the index erodibility was 0.3-0.5. Land used for mixed plants and shrubs, the texture dominated with silt loam-sandy clay loam, cation exchange capacity was 18.63-27.12 cmol+ kg-1, 1.09-2.89% of C-organic, 32-55% of base saturation, 0.2-4.9 cm/h of permeability, soil clay minerals were kaolinite-halloysite, and index erodibility was 0.1-0.3. Land use for cultivated in the high intensity of rainfall has changed the physicochemical properties of soils, but cultivated in monoculture has at some degree increased soil erodibility.
Climate anomalies lead to changes in rainfall patterns in Indonesia. Climate change has an impact on the increase in seasonal rainfall in December, January, and February, significantly in most areas in Java, Sulawesi, and Eastern Indonesia. Changes in the pattern of rainfall in Indonesia, especially for the sloping area of South Sulawesi, have resulted in increasing intensity of landslides. The objective of this study was to determine changes in rainfall patterns and erosivity that occur in East Luwu District which have an impact on landslide events. Rainfall data used from 1979 to 2017, erosivity value (R-factor) with Lenvain equation, IDW interpolation aplication are used for resulting erosivity map. Data from land cover, geology and soil are used as supporting data in the assessment of landslide events. Changes in the rainfall pattern since 1998-2017, as a result of global climate change, have resulted in increasing rainfall ability to erode the soil. Rainfall erosivity increased by 22% in 1999-2008, and increased to 33% in 2009-2017, most of the study areas in the last 10 years (2007-2017) have erosivity values (R-factor) >200 with high landslides activitty. The high level of rainfall erosivity could be reflected to the high level of climate variability as climate change phenomenon.
Lumpue Beach is an urban area in Parepare Bay with a harbour, tourism, and a landfill site. The purpose of this research was to determine the provenance, level and distribution of heavy metals in coastal sediments. Surface sediment samples were analysed for grain size, mineragraphy, petrography and total heavy metal content (Cu, Zn, Pb, Co, Ni, Fe). The minimum-maximum background enrichment factor (EF) range was calculated from the plagioclase mineral content of trachyte porphyry and andesite. Weathering alteration was quite high in trachyte porphyry rocks; andesite mineragraphy produced predominantly sedimentary plagioclase (25-45%), hornblende (10-40%), and rock fragments (40-45%). The grab sampling method produced samples dominated by plagioclase (30-50%), hornblende (15-40%) and alkaline chemical conditions were important in Fe, Ni, Pb, Cd, Cr, and Cu enrichment. Enrichment of heavy metals was supported by the mesokurtic-very leptokurtic dynamic sorting characteristics of Lumpue beach, becoming very leptokurtic - platykurtic to the north (Parepare Bay). The enrichment factor (EF) of Pb > 1 was calculated from the concentration of various non-earth sources. The order of heavy metal concentration based on EF 0.5 ≤ EF ≤ 1.5 was Pb> Zn> Cr> Fe> Cu> Ni, with Cu ≤ 0.5, indicating heterogeneous heavy metal sources correlated with urban area, river and ultrabasic regional lithology, with Trachyte-andesite alteration, especially enrichment in heavy metals Ni, Cr, Cu. Index of geoaccumulation (Igeo) was in the ranges: uncontaminated to heavily contaminated for Fe; uncontaminated to moderately contaminated for Cu, Zn, Ni, Cr and Cd; and uncontaminated for Pb. The intensity of heavy metal contamination followed the direction of sedimentation from various sources. Euclidian Cluster distance showed heavy metal distribution patterns correlated with rivers passing through urban areas and with regional geological lithology.
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