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Contact Name
Sri Mulyaningsih
Contact Email
sri_m@akprind.ac.id
Phone
+6222-7213793
Journal Mail Official
ijog@bgl.esdm.go.id
Editorial Address
Jl. Diponegoro No. 57 Bandung
Location
Unknown,
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INDONESIA
Indonesian Journal on Geoscience
ISSN : 23559314     EISSN : 23559306     DOI : https://doi.org/10.17014/ijog.3.2.77-94
Core Subject : Science,
The spirit to improve the journal to be more credible is increasing, and in 2012 it invited earth scientists in East and Southeast Asia as well as some western countries to join the journal for the editor positions in the Indonesia Journal of Geology. This is also to realize our present goal to internationalize the journal, The Indonesian Journal on Geoscience, which is open for papers of geology, geophysics, geochemistry, geodetics, geography, and soil science. This new born journal is expected to be published three times a year. As an international publication, of course it must all be written in an international language, in this case English. This adds difficulties to the effort to obtain good papers in English to publish although the credit points that an author will get are much higher. This Journal publishes 3 numbers per year at least 15 articles. It is a challenge for the management of the journal to remain survive and at the same time continuously maintain its quality and credibility in spite of those various constraints. Fortunately, this effort is strongly supported by the Geological Agency of Indonesia, as the publisher and which financially bear the journal. Last but not least the journal is also managed by senior geologist of various subdisciplines from various countries who are responsible for its quality.
Articles 323 Documents
Deep Sea Sediment Gravity Flow Deposits in Gulf of Tomini, Sulawesi Kusnida, Dida; Subarsyah, Subarsyah
Indonesian Journal on Geoscience Vol 3, No 4 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.4.217-224

Abstract

http://dx.doi.org/10.17014/ijog.vol3no4.20084Micro plate collision against the Eastern Arm of Sulawesi since Pliocene has resulted in a major supply of terigenous sediments into Late Miocene rift-basins in Gulf of Tomini. Studies on offshore multi-channel seismic reflection data complemented by published on-land geological data indicate a series of tectonic events that influenced the depositional system in the Gulf of Tomini. During the Late Neogene, alternating pulses of terigenous sediments were deposited in the basins in the form of deep-sea slump-turbidite-pelagic sediments. A sediment gravity flow deposit system at the slope and the base of the basins changed gradually into a deep-sea pelagic fill system toward the center of the basins. Three tectono-stratigraphy sequences (A, B, and C) separated by unconformities indicating the Late Neogene history and the development of the basins were identified. These tectonic processes imply that the earlier sediments in the Gulf of Tomini are accomplished by a differential subsidence, which allows a thickening of basin infill. The Pliocene-Quaternary basin fill marks the onset of a predominant gravity flow depositional system  
Seismotektonik dan Potensi Kegempaan Wilayah Jawa Soehaimi, A.
Indonesian Journal on Geoscience Vol 3, No 4 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.4.227-240

Abstract

http://dx.doi.org/10.17014/ijog.vol3no4.20085A seismogenetic study shows the Jawa Island Arc and its subduction zone system belong to a highly active seismotectonic arc unit (west Jawa and Sumatera) and an active seismotectonic arc unit (western part of West Jawa – Central Jawa – East Jawa). In general, these regions are part of the Indonesian Earthquake Hazard Zones No. VI, VII, VII and IX. The regions are characterized by the presence of rare earthquake of magnitude > 8.5 Richter Scale (western part of Java), frequent magnitude of 7 Richter Scale and common 5 - 6 Richter Scale (Southern part of Java). The potential hazardous earthquake in Jawa that is > 5,6 Richter Scale of magnitude and shallow depth (< 30 km) is due to a subduction zone earthquake. Epicenter distance, magnitude, geological site conditions, population, and infrastructure are the index of earthquake hazard and risk in these regions. The earthquake hazard mitigation programme in the near future is a risk assesment based on macro and microzonation of earthquake hazard and risk. These macrozonation and microzonation assessments are essentially needed for provinces, districts, and cities.    
Tsunamigenik di Selat Sunda: Kajian terhadap katalog Tsunami Soloviev Yudhicara, Yudhicara; Budiono, K.
Indonesian Journal on Geoscience Vol 3, No 4 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.4.241-251

Abstract

http://dx.doi.org/10.17014/ijog.vol3no4.20086Tsunamigenic is a natural phenomena which is potential to generate a tsunami, such as water dis- turbance due to the presence of activities of volcanism, earthquakes, coastal and sub marine landslidse, or other causal factors . Historically, the Sunda Strait has experienced several tsunami events recorded in the tsunami catalog. Those tsunamies were caused by some geological phenomena such as eruptions of Krakatau submarine volcano in 416, 1883, and 1928; earthquakes in 1722, 1852, and 1958; and other causes which were suggested as a mass failure of coastal and submarine landslide in 1851, 1883, and 1889. Tectonic condition of the Sunda Strait is very complicated, because this region is located at the boundary of Indian-Australian and Eurasian Plates, where a unique island arc system occurs with its association such as trench, accretionary zone, volcanic arc and back-arc basin. Sunda trench as a plate boundary is the most potential region to produce big earthquakes. Existence of a seismic gap in the region can cause a stress accumulation and store energy, then it will be released any time as a big earthquake to generate a tsunami. Along eruption history, Krakatau volcanic arc has four stages of reconstruction and three stages of destruction, and every destruction stage produces tsunami which is suggested to be potentially repeated in the future in a period between 2500 to 2700. Seafloor of the Sunda Strait has an unstable geological condition due to geological structure development, which creates grabens and also enable to produce submarine landslides triggered by earthquake. Coastal condition around the Semangko and Lampung Bays consisting of steep topography with high intensity of weathering, is another factor to contribute landslide, particularly in the case of triggering be heavy rainfall between December to Februari. Furthermore, if landslide materials tumble into the water, even very small and locally, could create a potency of tsunami.  
Tinjauan Kemungkinan Sebaran Unsur Tanah Jarang (REE) di Lingkungan Panas Bumi Herman, Danny Zulkifli
Indonesian Journal on Geoscience Vol 4, No 1 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.1.1-8

Abstract

http://dx.doi.org/10.17014/ijog.vol4no1.20091Geothermal areas occur mainly in an environment of volcanic/magmatic arc where magma chambers play a role as heat sources. The environment is situated within the convergent plate boundaries. A variety of igneous rocks is associated with this environment ranging from basalt (gabbro) to rhyolite (granite) but andesite is normally the most abundant igneous rock. The most obvious geothermal indications are exhibited by some surface manifestations comprising hot water seepage, fumaroles, hot spring, geyser, and hydrotermal alteration zones which are being evidences of an active hydrothermal system beneath the surface as a part of volcanism. Despite being a causal factor for alteration of country rocks, most hydrothermal fluids enable to change distribution pattern and content of rare earth elements (REE for instance Ce, Eu, La, Lu, Sm, Nd, and Y) particularly during a reaction process. This may have a connection with development of element mobility rates, whilst the characteristics of REE pattern within hydrothermal fluid would have a high variable due to dependency of their original magma source. Considering the important role of hydrothermal fluid in REE mobility development, it is inspired to review the possible relationship of active hydrothermal system and potency of REE distribution pattern in areas of geothermal manifestation.  
Identifikasi longsoran bawah laut berdasarkan penafsiran seismik pantul di perairan Flores Budiono, Kris
Indonesian Journal on Geoscience Vol 4, No 1 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.1.9-17

Abstract

http://dx.doi.org/10.17014/ijog.vol4no1.20092Submarine sliding frequently cause tsunami or a high velocity big wave around the submarine slid- ing area which enable to reach a long distance. This sliding is not always as a causal factor for hazard and even associate with storm and earthquake. Some of them occur in a narrow area and it’s just formed due to gravitational movement. Different with mechanism of landslide, which is commonly due to water saturated soil, the submarine sliding is a more complex event. The submarine sliding is an important natural process which causes a big volume of sediment mass moves from a shallow area to a much deeper area of seafloor. There are many types and causal factors of seafloor instability, but the sliding terminology is predominantly used for the phenomena. A variety of seafloor materials, environments and sediment masses are some extreme influential factors in creat- ing the types of submarine sliding. The reflector of seismics is usefull to interpret the indications of the occurrence of geological structure and sub-marine slumping In case of the Flores Sea, earthquake is a major causal factor for creating submarine sliding. The bigger magnitude of earthquake, the greater the dimension of submarine sliding. Eventually, it may affect to the more possible occurrence of a potential hazardous tsunami.  
Mineralogical Characteristics and The Pedogenetic Processes of Soils on Coral Reefs in Ambon Devnita, Rina
Indonesian Journal on Geoscience Vol 4, No 1 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.1.19-29

Abstract

http://dx.doi.org/10.17014/ijog.vol4no1.20093The mineralogical characteristics of soils developed on coral reef parent materials in Hitu and Wailiha, Ambon, were investigated regarding to the relationship to pedogenesis. The analyses concerned with the characteristics of soil chemical, physical, and mineralogy of the rock fragment and sand, silt and clay fractions are to investigate the pedogenesis processes. Both soil profiles indicate the clayey texture, slightly neutral reaction, high cation exchange capacity, base saturation, and iron oxide. The mineralogical analyses of rock fragments and sand fractions indicate that besides carbonate minerals, silicate minerals were also found. The clay mineralogy showing the domination of kaolinite, gibbsite, and goethite, reflects that the soil is intensely weathered. Pedogenesis process showing the clay translocation, indicates that the weathering process has been occuring under the tropical influence.    
A Review on Permian to Triassic Active or Convergent Margin in Southeasternmost Gondwanaland: Possibility of Exploration Target for Tin and Hydrocarbon Deposits in the Eastern Indonesia Amiruddin, Amiruddin
Indonesian Journal on Geoscience Vol 4, No 1 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.1.31-41

Abstract

http://dx.doi.org/10.17014/ijog.vol4no1.20094An active convergence of continental margin is probably generated in Gondwanaland during Permian to Triassic period which is characterized by the presence of magmatic and volcanic belts and back-arc ba- sins occupied respectively by Permian to Triassic rocks. The magmatic belt is occupied by peraluminous granitic plutons showing characteristics of S- type granite and is considered as tin-bearing granites. The back-arc basins are occupied by the Southern Papua and Galille-Bowen-Gunnedah-Sydney Basins. Those large basins are respectivelly filled by fluvial, fluvio- deltaic to marine Permian-Triassic sediments, which are unconformably overlain by the Jurrassic-Cretaceous marine succession. The paleomagnetic data, confirmed by flora content found in Australia and Papua, indicate that those areas initially belong to the Gondwanaland before part of them were drifted and rotated into the present day position. Tectonically, the presence of those Permian-Triassic magmatic-volcanic belts and back-arc basins in behind, indicates that at the time there were huge compressive activities: convergence of paleo-oceanic Pasific Plate moving westward, collided and subducted into the Southeastern Gondwana Continental Plate, moved relatively eastwards. This phenomenon resembles to the formation of Sumatera Tertiary tectonic zones producing back-arc basins, i.e. South Sumatera, Central, and North Sumatera Basins including the Tertiary Magmatic Arc. Concerning the similarity of Permian-Triassic geological condition of the magmatic arc and back-arc basins in Eastern Indonesia and Eastern Australia including paleoposition, paleotectonic setting, strati- graphic succession, and lithologic composition, it is suggested to carry out an increase in a more intens- ive tin exploration in the Eastern Indonesia, e.g. Bird Head area and Banggai Sula Island, and also for hydrocarbon target (coal, coalbed methane, oil and gas, and oil shale) in the Southern Papua Basin, East Indonesia. This suggestion is confirmed by cassiterite and hydrocarbon discoveries and exploitation activ- ity in the Eastern Australia and also a new seismic data of the Semai Basin a part of Southern Papua Basin. This seismic record shows a more complete stratigraphic sucession and a number of large structure traps of stratigraphic levels in which the Permian-Triassic units are included within the sequence.  
An appraisal for the petroleum source rocks on oil seep and rock samples of the Tertiary Seblat and Lemau Formations, Bengkulu Basin Panggabean, Hermes; Heryanto, R.
Indonesian Journal on Geoscience Vol 4, No 1 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.1.43-55

Abstract

http://dx.doi.org/10.17014/ijog.vol4no1.20095The Tertiary Bengkulu Basin is known as a typical fore-arc basin, situated in southwest Sumatera. The basin initiated during Eocene-Oligocene times, accumulates the Lahat equivalent formation. The formation is is unconformably overlain by the Oligocene-Miocene Hulusimpang Formation consisting of volcanic rocks. It is then succeeded by siliciclastics and minor carbonates of the Early-Middle Miocene of Seblat Formation. Unconformably overlying the Seblat is siliciclastics of the Middle-Late Miocene Lemau Formation, then overlain by the Late Mio-Pliocene Simpangaur Formation. The basin succession is terminated by the sequence of volcanic rocks named as the Bintunan or Ranau Formation. Geochemistry analyses (i.e. TOC, Rock-Eval and Gas Chromatography-Mass Spectrometry) conducted on selected outcrop and sub-crop samples, and one oil seep sample collected during field work, have given an appraisal to identify the nature of petroleum source rocks within the basin. The result of organic geochemistry and also organic petrology analyses indicates that potential source rocks may occurred in the stratigraphic succession of the basin. The Lahat equivalent formation, Seblat, and Lemau Formations may play an important role to generate oil within the Bengkulu Basin.  
Cinder cones of Mount Slamet, Central Java, Indonesia SutawIdjaja, Igan S.; Sukhyar, R.
Indonesian Journal on Geoscience Vol 4, No 1 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.1.57-75

Abstract

http://dx.doi.org/10.17014/ijog.vol4no1.20096The Mount Slamet volcanic field in Central Java, Indonesia, contains thirty five cinder cones within an area of 90 sq. km in the east flank of the volcano. The cinder cones occur singly or in small groups, with diameter of the base ranges from 130 - 750 m and the height is around 250 m. Within the volcanic field, the cinder cones are spread over the volcanic area at the distance of 4 to 14 km from the eruption center of the Slamet Volcano. They are concentrated within latitudes 7°11’00” - 7°16’00” S,, and longitudes 109°15’00” - 109°18’00” E. The density of the cinder cones is about 1.5 cones/km2. Most of the cinder cones lie on the Tertiary sedimentary rocks along the NW-trending fault system and on radial fractures. The structural pattern may be related to the radial faults in this region. The cone surfaces are commonly blanketed by Slamet air-falls and lava flows. The deposits consist of poorly bedded, very coarse-grained, occasionally overlain by oxidized scoria, and large-sized of ballistic bombs and blocks. There are various kind of volcanic bombs originating from scoriae ballistic rock fragments. The other kind of volcanic bombs are breadcrust bomb, almond seed or contorted shape. All of the cinder cones have undergone degradation, which can be observed from the characters of gully density and surface morphology. By using Porter parameters, Hco is equal to 0.25 Wco, whilst Wcr is equal to 0.40 Wco. The Hco/Wco ratio is higher than Hco = 0.2 Wco reference line. A radiometric dating using K-Ar method carried out on a scoria bomb yields the age of 0.042 + 0.020 Ma.  
Waduk Parangjoho dan Songputri: Alternatif Sumber Erupsi Formasi Semilir di daerah Eromoko, Kabupaten Wonogiri, Jawa Tengah Bronto, Sutikno; Mulyaningsih, Sri; Hartono, G.; Astuti, B.
Indonesian Journal on Geoscience Vol 4, No 2 (2009)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.4.2.77-92

Abstract

http://dx.doi.org/10.17014/ijog.vol4no2.20091The Semilir Formation was typically originated from products of a very explosive volcanic activity, i.e. breccias, lapillistones, and tuffs containing abundant pumice. It has a light grey to white colour and high silica andesite to dacite in composition, mainly rich in volcanic glass and quartz. Sedimentary structures of these volcanic rocks are massive, grading, planar bedding, and cross-bedding to antidunes, with grain size varies from ash (≤ 2 mm) to lapilli (2 – 64 mm) to bomb and block (> 64 mm). The formation is widely distributed from the west side (Pleret and Piyungan areas, Bantul Regency, Special Province of Yogyakarta) until Eromoko area in the east (Wonogiri Regency, Jawa Tengah Province). Stratigraphically, the Semilir Formation underlies the Nglanggeran Formation, and overlies the Mandalika Formation in the eastern part and Kebo-Butak Formation in the western part. Geomorphological- and lithological analyses of the Semilir Formation in areas of Parangjoho and Song- putri Dams, Eromoko Sub-regency, Wonogiri Regency indicate that the two depressions were alternatively volcanic sources of the Semilir Formation in the Eromoko area. This is proved by the presence of co-ignimbrite breccias(co-ignimbrite lag fall deposits), that descriptively they are polymict breccias. This rock is characterized by a mixing of pumice and various hard rock fragments that primarily are juvenile materials (volcanic blocks, bombs), accessory-, and accidental rock fragments set in pumice-rich volcanic ash and lapilli sizes. The accessory materials came from older volcanic rocks, whereas the accidental ones were originated from basement rocks. During a caldera forming event or a destruction period of an older composite volcanic cone(s), all older rocks resting above the magma chamber were ejected to the surface by a very high magmatic pressure. Since they were heavier than the juvenile material, most accessory and accidental rock fragments were left (lag fall) in caldera rim behind the ash and pumice flow. In the dam areas of Parangjoho and Songputri, the lag fall fragments consisting of andesite, pyroxene andesite, dacite, and pumice, being 10 – 150 cm in diameter are set in pumice-rich lapilli tuffs. Some of the rock fragments are volcanic blocks and bombs, while the older rocks are angular to very angular shape, having prismatic jointing or jigsaw-crack structures. The eruptions in the Parangjoho and Songputri craters were controlled by north-south trending fractures, and they resemble to the Katmaian caldera explosion type.  

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