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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
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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
Sedimentation Process of Rambatan Formation in Larangan Brebes, North Serayu Range, Central Java Astuti, Bernadeta Subandini; Isnaniawardhani, Vijaya; Abdurrokhim, Abdurrokhim; Sudradjat, Adjat
Indonesian Journal on Geoscience Vol 6, No 2 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.2.141-151

Abstract

DOI:10.17014/ijog.6.2.141-151Rambatan Formation in the western part of North Serayu Basin, Brebes, Central Java, comprises generally flysch facies of turbidite sediments deposited in a deep marine environment. This formation is equivalent to Merawu Formation found in the eastern part of the basin and deposited in the environment of tidal flat to subtidal. The turbidite sediments were highly controlled by a rapid downward movement taking place continuously during Early to Late Miocene. The variation of the depositional environment has been the object of this research which aims to understand the sedimentation process of Rambatan Formation in this type locality with a modern turbidite approach. Rambatan Formation was deposited in N13-N19, as a deep marine sediment channel, turbidite, and deep marine tidal zone. The sedimentation was affected by gravity flow and contourite. The sediments on N13-N14 were marked by turbidite sediments until Middle N17. The sediment supply increased on Middle N17, as a sediment filler on a channel marked by contourite mud layer (muddy slump) and debris flow, with sources from the north. The increase of sediment supply was followed by an environmental transformation from a deep marine channel into deep marine tidal area. In N19, the sediments were redeposited as turbidite sediment, starting with debris flow in Middle N18.
Exhumation and Tectonomagmatic Processes of the Granitoid Rocks from Sulawesi, Indonesia: Constrain from Petrochemistry and Geothermobarometry Study Maulana, Adi; Imai, Akira; Watanabe, Koichiro; van Leeuwen, Theo; Widodo, Sri; Musri, Musri
Indonesian Journal on Geoscience Vol 6, No 2 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.2.153-174

Abstract

DOI:10.17014/ijog.6.2.153-174Exhumation and tectonomagmatic processes of the granitoid from Sulawesi were discussed using petrochemistry (e.g. petrographic and major element compositions) and geothermobarometry data (mineral chemistry data). Detailed petrographic observations were conducted to determine the mineral composition, texture, and structure of the granitoid rocks, whereas the whole rock composition were determined using XRF method, and the mineral chemistry was analyzed using Electron Microprobe Analyzer (EPMA). The granitoids are classified as calc-alkaline, metaluminous I-type. Pressures of 0.91 to 1.2 kbar and emplacement depths of 3.2 to 4.3 km at temperatures of 677 - 729°C were estimated for Mamasa Pluton. Whereas Masamba Pluton was emplaced at pressures of 2.3 to 2.8 kbar, temperatures of 756 - 774°C, and emplacement depths of 8.2 to 10 km. Moreover, Lalos-Toli and Sony Plutons were emplaced at temperatures of 731 to 736°C and 601 to 609°C, respectively. The pressures varying from 3.1 to 3.3 kbar and 3.2 to 3.4 kbar, equate to an emplacement depth of 11.3 and 11.6 km, respectively. Gorontalo Pluton emplaced at temperatures of 662 - 668°C with the pressure range from 2.6 to 2.7 kbar, is equivalent to 9.3 km deep. Varied oxidation state (ranging from -14 to 19) is inferred from the mineral assemblages, showing a strong association with highly oxidized I-type series granitic rocks. The exhumation rate estimation shows that Mamasa and Masamba Plutons were exhumed respectively at a rate of 0.37 and 1.6 mm/year, whereas Lalos-Toli and Sony Plutons at 1.4 and 2.7 mm/year, respectively. Gorontalo Pluton located in the Northern Sulawesi Province was exhumed at 0.42 mm/year. The rapid exhumation rate of Sony Pluton is attributed to the active vertical movement of Palu-Koro Fault Zone which has been active since Pliocene. It shows that faulting may play an important role in differential exhumation of intrusive bodies in the orogenic belt.
Mineralogical and Geochemical Characterization of Jordanian Olivine and Its Ability to Capture CO2 by Mineralization Process Dwairi, Reyad Al
Indonesian Journal on Geoscience Vol 6, No 2 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.2.175-183

Abstract

DOI:10.17014/ijog.6.2.175-183Olivine rich rocks outcrop in Kharazeh area (KHO) and Jurf Eldaraweesh (JDO) Basaltic rocks southern Jordan. KHO and JDO have been characterized for their mineralogical and geochemical properties investigated for their potential use in CO2 capture by mineralization process. The effects of particle size, temperature, and contamination time were examined in the mineralization process. Two grain sizes of olivine for each type were used in capture experiments. The first grain size is the separated size fraction between 1 to 0.7 mm (KHO1 and JDO1), while the second grain size is the separated size fraction between 0.7 to 0.3 mm (KHO2 and JDO2). For the mineralization purpose, a chemical reactor was used to determine the olivine CO2 capture capacity. Thin section studies aided by XRD identification for KHO indicated the presence of olivine crystals as the main mineral with percentage reaches 48% plagioclase, augite, and magnetite. While the mineral content for JDO is (35%) olivine, plagioclase, clinopyroxene, and opaque minerals. Olivine chemical composition results show the high MgO percentage for KHO ranges between 47.5 and 50.13%, while the percentage of MgO varies from 43.6% and 44.6% for JDO. The CO2 mineralization process results were interpreted using percentage removal curves. CO2 capture percentage reaches the highest percentage (48%) using KHO2 and 100o C temperature. In summary, it can be concluded that CO2 can be removed from atmosphere using Jordanian olivine rich rocks.
Facies Associations of Early Cretaceous Arumit Formation and Early to Late Cretaceous Ungar Formation in Vulmali and Ungar Islands, Tanimbar (Indonesia) Fakhruddin, Rakhmat
Indonesian Journal on Geoscience Vol 6, No 2 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.2.185-208

Abstract

DOI:10.17014/ijog.6.2.185-208Cretaceous sediments are among the important petroleum system elements for hydrocarbon exploration in Tanimbar area. However, little is known about their facies associations and depositional environments. Facies association analyses have been carried out in fourteen surface sections. Early Cretaceous Arumit Formation comprises three facies associations: subtidal, intertidal, and supratidal deposits. A progradational open-coast tidal flat depositional environment suggests the deposition of sediments of the Arumit Formation. The presence of tidal rhythmites, mud drapes, and fluid mud in those sediments are diagnostic features of a tide domination process in deposition of this unit. Early to Late Cretaceous Ungar Formation in the studied area consists of four facies associations: intertidal, marine offshore to lower shoreface, upper shoreface, and foreshore deposits. An open-coast wave dominated depositional environment is proposed for deposition of sediments of the Ungar Formation. Wave dominated environments in the coarsening upward interval is represented by hummocky cross stratification, cross-bedded sand and gravel, planar parallel stratification, and low-angle stratified beds.
Characteristics of Arun Carbonate Reservoir and Its Implication To Optimize the Most Potential Gas Resource Zone In Arun Gas Field, Aceh, Indonesia Atmadibrata, Riza; Muslim, Dicky; Hirnawan, R. Febri; Abdurrokhim, Abdurrokhim
Indonesian Journal on Geoscience Vol 6, No 2 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.2.209-222

Abstract

DOI:10.17014/ijog.6.2.209-222Since the discovery of major oil and gas reserves in carbonate rocks in the Middle East, carbonate reservoirs became important to the petroleum industry. Carbonate rocks have covered only 20% of the sedimentary rock records. However, carbonate reservoirs hold 50% of the world petroleum reserves. Arun Carbonate Reservoir is one of the biggest proven retrograde gas reservoirs in the world. After more than thirty years of production, Arun Carbonate Reservoir had an initial gas in place of 14.1 TCF residual hydrocarbon gas. The issue makes Arun Carbonate Reservoir became an interest to be studied for the development and production of hydrocarbon in other carbonate reservoirs in Indonesia. One of the fundamental topics to be studied is the characteristics of Arun Carbonate Reservoir itself. The characteristics of carbonate reservoir usually cause a lot of geologic and engineering problems in the development and production of hydrocarbon reserves. This paper aims to identify the characteristics of Arun Carbonate Reservoir and its implication to delineate the potential gas resource zone in the Arun Gas Field, Aceh, Indonesia. The data from sixteen wells have been examined through several multidiscipline studies: geophysics (well logging), geology (facies, lithology and diagenetic analyses), and petrophysics (core analysis). The result of this study shows that Arun Carbonate Reservoir (N5-N8) contains limestone 92%, 5% dolomite, and 3% dolomitic limestone (or other), and petrophysically have 16% porosity and 13.5 md permeability in average. Arun Carbonate Reservoir is divided into four facies (Reef, Near Reef, Inter Reef Lagoon, and Middle Shelf). Of four facies in Arun Carbonate Reservoir, only two facies which can be categorized as productive facies: Reef and Lagoonal Facies. The potential zones of hydrocarbon resources have vertically been documented in Arun Carbonate Reservoir.
Multi-Ricker Spectral Modeling in the S-transform Domain for Enhancing Vertical Resolution of Seismic Reflection Data Winardhi, Sonny; Pranowo, Waskito
Indonesian Journal on Geoscience Vol 6, No 3 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.3.223-233

Abstract

DOI: 10.17014/ijog.6.3.223-233We present a relatively straightforward methodology for extending seismic bandwidth and hence enhancing the seismic resolution by performing time-variant deconvolution. We use the generalized S-transform (GST) approach in order to properly compute the time-frequency components of the seismic reflection trace. In estimating the time-variant wavelet, we propose a spectral modeling method named multi-Ricker spectral approximation (MRA). After obtaining the estimated wavelet spectrum at each time sample, a deconvolution filter can then be built and applied in the S-transform domain. This proposed time-variant seismic enhancement method needs neither information on subsurface attenuation model nor assumption that the subsurface reflectivity is random. It is a data-driven methodology which is based on the seismic data only. We validate this proposed method on a synthetic and apply to a field data. Results show that, after enhancement, overall seismic bandwidth can be extended resulting in higher vertical resolution. Correlation with VSP corridor stack at well location ensures that the generated reflection details after enhancement is geologically plausible.
Tephra-stratigraphy and Ash Componentry Studies of Proximal Volcanic Products at Mount Tangkuban Parahu, Indonesia: An Insight to Holocene Volcanic Activity Angkasa, Syahreza S.; Ohba, Tsukasa; Imura, Takumi; Setiawan, Iwan; Rosana, Mega
Indonesian Journal on Geoscience Vol 6, No 3 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.3.235-253

Abstract

DOI: 10.17014/ijog.6.3.235-253Tangkuban Parahu Volcano is one of the most active volcanoes in West Java, Indonesia, although most of the recent eruptions were relatively mild (e.g. 2013 eruption). However, there is still little information from the volcanic products in the proximal area. Here, a new documentation from the proximal volcanic succession is provided, including tephra-stratigraphy, componentry analysis, and petrography of volcanic products. Detailed mapping of the proximal area shows that the volcanic products are predominantly composed of alternating fine-clay and coarse ash, lapilli tuff, and pyroclastic breccia within ten tephra units. Componentry of ash particles revealed the presence of five components, associated with hydrothermally altered lithics, oxidized lithics, coherent crystalline lithics, magmatic juvenile, and free crystal in entire eruptive products. These indicate that the subvolcanic hydrothermal system has been developed since the Holocene and associated with a continual introduction of magmatic intrusion. Petrographic observation shows the presence of hydrothermal minerals of quartz or silica accompanied by alunite and kaolinite, representing acidic alteration within the crater-conduit. The existence of a silicified zone indicates that the subvolcanic hydrothermal system played an essential role as a cap-rock of pressurized gas and steam at depth (200-500 m), whereas magmatic injection caused the vapour plume expansion. The observation concluded that the proximal volcanic succession captured the evidence of coupled phreatic and phreatomagmatic activities during the latest development of Mount Tangkuban Parahu.
The Gondwanan Green Alga Tasmanites sp. in the Permian Lacustrine Deposits of West Timor Lelono, Eko Budi
Indonesian Journal on Geoscience Vol 6, No 3 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.3.255-266

Abstract

DOI: 10.17014/ijog.6.3.255-266This paper discusses a palynological research on the Permian lacustrine sediments of West Timor. Ten outcrop samples were collected from a 5 m high cliff. Lithologically, the outcrop mostly consists of noncalcareous black shale showing papery structures and forms part of Bisane Formation. Palynomorphs extracted from the studied samples are rich, but of a low diversity indicating a non-marine environment. More than 80% of pollen assemblages are of the green alga Tasmanites sp., whilst the rest are mostly represented by striate and non-striate bisaccate pollen and trilete spores which indicate a Permian age. The chromatograms of GC and GCMS (saturate) indicate that the studied samples were deposited in a lacustrine environment of an anoxic to suboxic condition. Furthermore, in term of petroleum exploration, abundant Tasmanites sp. is believed to be the biological source for tricyclic terpanes which are well known as the primary source of hydrocarbons. This discovery offers an excellent opportunity for establishing a new petroleum system within the Paleozoic sequences of Timor Island.
Tertiary Sequence Stratigraphy of Bird Head Area, Eastern Indonesia Alam, Syaiful; Setiadi, Djadjang Jedi
Indonesian Journal on Geoscience Vol 6, No 3 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.3.267-278

Abstract

DOI: 10.17014/ijog.6.3.267-278 A long depositional period of Papua limestone called Kais Formation, which is overlain by clastic sediments of Steenkool Formation, reflects an interesting stratigraphic architecture in the West Papua region. Using seismic stratigraphic method of five stacking patterns, forestepping, downstepping, upstepping, backstepping, and seismic facies (parallel, prograding clinoform, channel fill, mounded) have been observed. Chronostratigraphic reconstruction was completed to figure out the depositional units in space and time. This study reveals the lowstand deposit during Early to Middle Eocene (LST), transgressive-highstand carbonate deposit during Middle Eocene to Middle Oligocene, and transgressive-highstand silisiclastic (TST-HST) deposit during Middle Miocene - Late Pliocene.  
Determination of Hypocentre and Seismic Velocity Structure in Guntur Volcano Using Seismic Data from 2010 to 2014 Basuki, Ahmad; Nugraha, Andri Dian; Hidayati, Sri; Triastuty, Hetty
Indonesian Journal on Geoscience Vol 6, No 3 (2019)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.3.279-289

Abstract

DOI: 10.17014/ijog.6.3.279-289Guntur Volcano was in a dormant state even though its seismicity had increased on April, 2013 and August, 2013. In this study, determination of hypocentre and seismic velocity structure was conducted using seismic data from 2010 to 2014 as recorded by a seismic station of the Centre for Volcanology and Geological Hazard Mitigation of Indonesia (CVGHM). Volcano-Tectonic (VT) earthquakes were identified and carefully picked for P-and S-wave arrival times. More than 600 events of VT earthquakes from 2010 - 2014 were located using maximum likelihood estimation algorithm. The initial 1-D seismic velocity was calculated using Velest method in order to get the initial velocity as the input for the tomographic inversion. The results show distribution of VT hypocentres were clustered in three regions, namely Guntur Volcano, Kamojang geothermal area, and Darajat geothermal area. At the Guntur Volcano region, the VT events were located mostly at the northern part of the crater with the depth of hypocentre ranges from 0 - 4 km. The distribution of the VT events made alignment from the southwest to the northeast with the depth of hypocentre mostly ranges from 0 - 2 km at Kamojang region. Meanwhile, at Darajat geothermal area, the VT events were located at the depth of 0 - 2 km and made alignment from the southeast to the northwest. The low velocity zone associated with hot material or fluids was located at the depth of 5 km beneath the Guntur Crater. The location of VT earthquakes at the depth of 0 - 4 km beneath Guntur Crater was coincided with the area with high Vp and Vs anomalies. The low velocity zones were also found at Kamojang Crater and Cipanas hotspring area. It was predicted that the low velocity zone at the Kamojang Crater was related to a high temperature of the vapour system, whereas the reservoir of water was preferred to be dominated at the Cipanas hotspring.