Kabupaten Minahasa Tenggara merupakan salah satu daerah berkembang yang memiliki banyak Daerah Aliran Sungai (DAS), diantaranya adalah DAS Molompar dan Totok. Tujuan dilakukannya studi ini adalah untuk mengetahui karakteristik DAS Molompar dan DAS Totok berdasarkan analisis morfometri. Parameter yang digunakan adalah pola pengaliran, luas DAS, rasio lingkaran (circularity ratio), nisbah perpanjangan sungai (elongation ratio), tingkat percabangan sungai (bifurcation ratio), dan kerapatan sungai (drainage density). Penelitian ini menggunakan data Peta Rupa Bumi Indonesia (RBI). Hasil penelitian menunjukkan Kabupaten Minahasa Tenggara memiliki banyak sungai berpola dendritic, trellis, pinnate dan parallel. Luas DAS Molompar 154,12 km2 dan terhitung sebagai sungai berukuran sedang. Luas DAS Totok sebesar 77,84 km2 dan tergolong sebagai sungai berukuran kecil. Rasio lingkaran (Rc) untuk DAS Molompar adalah 0,4673 dan DAS Totok 0,54, sedang untuk nisbah perpanjangan sungai (Re) masing masing adalah 0,14 dan 0,329. Nilai tingkat percabangan sungai (Rb) dan nilai kerapatan sungai (Dd) pada kedua sungai itu rendah. Hasil untuk kedua sungai tersebut mengindikasikan kedua sungai memanjang sehingga waktu konsentrasi air lebih lama dan fluktuasi banjir lebih rendah. Kedua DAS tersebut memiliki relief yang tinggi/ kasar, kemiringan lereng yang curam, berada pada area dengan permeabilitas yang tinggi dan tingkat vegetasi yang rapat. Selain itu, parameter tersebut juga menunjukkan kedua sungai tersebut tidak dipengaruhi oleh struktur geologi. Hasil dari penelitian ini diharapkan mampu menjadi tambahan wawasan dalam pengelolaan DAS tersebut. Southeast Minahasa Regency is one of the developing areas which has many watersheds, including the Molompar and Totok watersheds. The purpose of this study was to determine the characteristics of the Molompar and Totok watersheds based on morphometric analysis. The parameters used are the drainage pattern, the area of the watershed, the circularity ratio, the elongation ratio, the bifurcation ratio, and the drainage density. This research uses Indonesia Topographical map data processing. The results showed that Southeast Minahasa Regency has many rivers with dendritic, trellis, pinnate, and parallel patterns. The area of ??the Molompar watershed is 154.12 km2 and is considered a medium-sized river. The Totok watershed area is 77.84 km2 and is classified as a small river. The circularity ratio for the Molompar watershed is 0.4673 and the Totok watershed is 0.54, while the elongation ratio is 0.14 and 0.329, respectively. The value of the bifurcation ratio and the drainage density (Dd) in the two rivers are low. The results for the two rivers indicate that both rivers are elongated so that the water concentration time is longer and the flood fluctuation is lower. The two watersheds have high/ rough relief, steep slopes, are in areas with high permeability and dense vegetation levels. Besides, these parameters also indicate that the two rivers are not influenced by geological structures. The results of this study are expected to provide additional insight into the management of that watershed in Southeast Minahasa Regency, North Sulawesi Province.

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Anabanua Village, Barru Regency is one of the areas in South Sulawesi that has quite unique geological conditions. This condition inseparably comes from the complicated geological process that took place during the formation of the island, Sulawesi. In Anabanua Village, there are many types of rocks such as sedimentary rocks, metamorphic rocks and igneous rocks. This paper aims to map and classify the types of rock by taking samples on different places in the research area. Then we observe the samples physical properties. The results showed, from taking 10 rock samples in different places, they have various characteristics. 8 of them were sedimentary rocks, they are Limestone Quartz, Limestone Sand, Shale, Sandstone, Coal, Limestone Bioturbation, Breccia, and Chert Stone. The other 2 samples were metamorphic rocks, they are Greenschist and Quartzite.

AbstrakPenelitian ini bertujuan menentukan faktor utama penyebab longsor di Kabupaten Toraja Utara. Parameter yang digunakan yaitu elevasi, kemiringan lereng, aspek lereng, geologi, tekstur tanah, kelurusan, jarak dari jalan, jarak dari sungai, curah hujan dan penutupan lahan. Penelitian ini menggunakan metode AHP (Analytical Hierarchy Process). Berdasarkan hasil penelitian faktor utama penyebab terjadinya longsor adalah parameter curah hujan dengan bobot 0.317, kemudian tekstur tanah, jarak dari jalan, jarak dari sungai, geologi, penutupan lahan, kelurusan, kemiringan lereng, aspek lereng dan parameter yang memperoleh bobot terkecil yaitu elevasi dengan bobot 0.027..Kata Kunci : Faktor utama, longsor, AHP (Analytical Hierarchy Process), Toraja UtaraAbstractThe purpose of this research is to determine the main factor that causing landslides in North Toraja District. They are several parameters used to adjust the landslides at that area i.e. elevation, slope, geology, soil texture, alignment, distance from the road, distance from the river, rainfall and land cover. This research uses the AHP (Analytical Hierarchy Process) method to show a factor dominated causing landslides. The results show that the main factors causing the landslide are rainfall with the weight factor is 0.317, following by soil texture, distance from the road, distance from the river, geology, and land cover is about 0.027.Keywords: Main factor, landslide, AHP (Analytical Hierarchy Process), North Toraja

AbstrakKajian terhadap daerah rawan bencana kegempaan dan tsunami di Kabupaten Bulukumba dilatarbelakangi oleh kondisi struktur geologi dan geomorfologi di daerah tersebut. Keberadaan satuan batuan yang menyusun geomorfologi Bulukumba mempunyai dimensi yang berbeda-beda. Batuan tertua berumur Miosen tengah (Bedrock) berada pada pemekaran dasar laut Teluk Bone  sementara batuan termuda berumur Plistosen berada pada sesar Walanae di daratan Bulukumba (Formasi Lompobattang). Hal ini menandakan sistem tektonik yang bekerja tidak selalu sama. Struktur geologi di daerah ini menyebabkan kondisi yang tidak stabil. Ketidakstabilan ini mengancam keberadaan daerah dan masyarakat Bulukumba. Metoda analisis data yang digunakan dalam penelitian adalah deduksi probabilistik dengan pendekatan dedukto-hipotetiko-verifikatif..Data primer diperoleh melalui survei lapangan, sedangkan data sekunder dikumpulkan melalui penelusuran literatur kepustakaan. Analisis data menggunakan analisis statistik sederhana. Berdasarkan perhitungan parameter kewaspadaan diperoleh tingkat pengetahuan kegempaan dan tsunami masyarakat di Kecamatan Rilau Ale, Bulukumba rata-rata bernilai 5,44 berkategori sedang. Tingkat sikap rata-rata bernilai 71,19 berkategori tinggi, sedang tingkat kesiapsiagaan bernilai 49,17 berkategori kurang siap.Kata Kunci: Kegempaan, tsunami, struktur geologi, geomorfologi, analisis statistik.AbstractThis study at tsunami and earthquake of the Bulukumba region by considering the geological and geomorphological condition of the area as the background. The geomorphology of Bulukumba region is formed by various lithologies. The oldest rock of Middle Miocene is found at Teluk Bone Sea floor spreading while the newest one of the Plistocene (Lompobattang Formation) is found at Walenae fault (Bulukumba terrain). This fact indicates the existence of different tectonic system in the area. Inevitably, the geological structure causes instability at its region. The instability becomes a serious threat to the peoples of Bulukumba region. The method used for data analysis in this study is the deductive-probabilistic method with a hipothetic-verificational approch. Two method of data retrieval have been used ie, the field survey of the area (questionnaire method), and the literatures  collection. The standard statistical analysis is used to test the data. The calculation of the vigilance parameter has shown that the arverage tsunami and earthquake level of students knowled in the Rilau Ale district is average 54,4 (moderate category). The level of attitude is average 71,19 (high category), while the level of preparedness is worth 49,17 (poorly prepared category).Keywords : Earthquake, Tsunami,  geological structure, geomorphology, statistical