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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
The origin of Cihara granodiorite from South Banten Hartono, Udi; Syafri, Ildrem; Ardiansyah, Reza
Indonesian Journal on Geoscience Vol 3, No 2 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.2.107-116

Abstract

http://dx.doi.org/10.17014/ijog.vol3no2.20085Petrographical and geochemical characteristics of the Late Oligocene Cihara Granodiorite from South Banten are presented. Data show that the rock was originated from magma of a continental origin formed at a subduction zone environment. Fractional crystallization involving plagioclase, hornblende, pyroxene, and magnetite was the main process responsible for the geochemical variation of the rocks from the Cihara Granodiorite. There are two possibilities of parental magmas to the Cihara Granodiorite, i.e. the basaltic/ or andesitic magma of the Cikotok Formation or crustal melting magma from a subduction process. Some trace element data of the basaltic rocks from the Cikotok Formation are needed to support the first interpretation. Alternatively, heating of the Jawa lower crust by magma from either mantle or subducted slab melting caused the crustal melting to produce intermediate parent magma. Some degree of mixing between those two differ- ent magma sources during the fractionation may be involved in the petrogenesis.    
Gunung Api purba Watuadeg: Sumber erupsi dan posisi stratigrafi Bronto, Sutikno; MulyaningSih, Sri; Hartono, G.; Astuti, B.
Indonesian Journal on Geoscience Vol 3, No 3 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.3.117-128

Abstract

http://dx.doi.org/10.17014/ijog.vol3no3.20081Pillow lava flows of pyroxene basalt containing 50 wt.% SiO are exposed at Opak River, west of Watuadeg Village, Sleman - Yogyakarta. The length of flow structures is between 2 – 10 m, with diameter of 0.5 – 1.0 m and it has a glassy skin at the surface body. Flow directions vary from N70E in the northern side, through N 120E in the middle to N 150E in the southern side. About 150 m away from the river to the west, there is a small hill about 15 m high, that has a similar composition with the pillow lavas. Both lava flows and the small hill are composed of pyroxene basalt, dark grey in color, hypocrystalline vitrophyre to porphyritic texture, with fine-grained phenocrysts of pyroxene (10 %) and plagioclase (25 %) set in glassy groundmass. These data indicate that the small hill was the eruption source of the basaltic pillow lavas. The lavas are overlain by pumice-rich volcaniclastic rocks, composed of tuff, lapillistones and pumice breccias, that are known as the Semilir Formation. Near the contact with lavas, the volcaniclastic rocks contain some fragments of pyroxene basalt, similar composition with the pillow lavas. This fact, together with analyses of petrology, volcanology, and radiometric dating show that the basaltic pillow lavas are unconformably overlain by the Semilir Formation.  
Reaktivitas Sesar Kaligarang, Semarang Poedjoprajitno, S.; Wahyudiono, J.; Cita, A.
Indonesian Journal on Geoscience Vol 3, No 3 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.3.129-138

Abstract

http://dx.doi.org/10.17014/ijog.vol3no3.20082Kaligarang Fault which cuts across Semarang City in a north-south direction has been activated for long periods. During Tertiary time, the Kaligarang Fault experienced a dextral wrench movement, which was triggered by a tectonic activity during that time, with a maximum principal stress (σ 1) in a northeast - southwest direction. While on Quaternary time, this fault was reactivated as a sinistral wrench fault. Reactivation of this fault was caused by a principal stress (σ 2) in a north east - south last direction.    
Pencemaran air raksa (Hg) sebagai dampak pengolahan bijih emas di Sungai Ciliunggunung, Waluran, Kabupaten Sukabumi Widodo, Widodo
Indonesian Journal on Geoscience Vol 3, No 3 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.3.139-149

Abstract

http://dx.doi.org/10.17014/ijog.vol3no3.20083Gold ore mining at Waluran Subregency, Sukabumi Regency was carried out by an underground mining method, and only rock that contains high enough gold ore would be taken (selective mining). The gold ore from the mining was processed with a direct amalgamation method, so it produced low gold concentrate, but the concentrate of mercury discarded to the river was high enough. Monitoring result of water and sedimentation in Ciliunggunung River in 2004, showed that the river was contamined by mercury (Hg), and the contamination was above the value limit. This happened especially in August 2005 where the Hg content was about 0.218 mg/l on the Ciliunggunung River in CLG.07. The chemical analysis result of heavy metals for the water of the Ciliunggunung River in CLG.07 was known to contain Fe above the standard drinking water criteria, meanwhile Mn, Cu, Pb, and As were still under the maximum drinking water criteria value. To decrease the mercury contamination, it is suggested the process of gold ore from the amalgamation direct method to be changed to the amalgamation indirect method. The indirect gold ore amalgamation process consists of: removing fine particles by washing, grinding ore, and the amalgamation phase. The total impact of the indirect amalgamation method will increase the tying of gold by mercury, so the losing of mercury will be decreased and the gain of gold will be optimum.  
Estimation of Bouguer Density Precision: Development of Method for Analysis of La Soufriere Volcano Gravity Data Gunawan, Hendra; Micheldiament, Micheldiament; Mikhailov, Valentin
Indonesian Journal on Geoscience Vol 3, No 3 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.3.151-159

Abstract

http://dx.doi.org/10.17014/ijog.vol3no3.20084The precision of topographic density (Bouguer density) estimation by the Nettleton approach is based on a minimum correlation of Bouguer gravity anomaly and topography. The other method, the Parasnis approach, is based on a minimum correlation of Bouguer gravity anomaly and Bouguer correction. The precision of Bouguer density estimates was investigated by both methods on simple 2D syntetic models and under an assumption free-air anomaly consisting of an effect of topography, an effect of intracrustal, and an isostatic compensation. Based on simulation results, Bouguer density estimates were then investigated for a gravity survey of 2005 on La Soufriere Volcano-Guadeloupe area (Antilles Islands). The Bouguer density based on the Parasnis approach is 2.71 g/cm3 for the whole area, except the edifice area where average topography density estimates are 2.21 g/cm3 where Bouguer density estimates from previous gravity survey of 1975 are 2.67 g/cm3. The Bouguer density in La Soufriere Volcano was uncertainly estimated to be 0.1 g/cm3. For the studied area, the density deduced from refraction seismic data is coherent with the recent Bouguer density estimates. New Bouguer anomaly map based on these Bouguer density values allows to a better geological intepretation.    
Fasies dan lingkungan pengendapan Formasi Bobong berumur Jura sebagai pembawa lapisan batubara di Taliabu, Kepulauan Sanana-Sula, Maluku Utara Kusnama, Kusnama
Indonesian Journal on Geoscience Vol 3, No 3 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.3.161-173

Abstract

http://dx.doi.org/10.17014/ijog.vol3no3.20085The Bobong Formation is a coarse clastic sedimentary rock succession. In the lower part, it consists of breccia and conglomerate facies, then followed by quartz sandstone with intercalations of claystone facies. Upwards, the rock succession is gradually changed to become alternating shale, claystone and mudstone. In the upper section the rock unit is well exposed in the western and northern parts of the Taliabu Island. The formation is Jurassic in age and it was deposited within a fluvial-transition to shallow marine environ- ment. The coal bed found within quartz sandstone and shale and claystone-mudstone facies ocupies the upper part succession of the Bobong Formation. The coal in the Taliabu Island has two seams having a thickness of 30 - 40 cm and 100 - 120 cm, respectively. The geochemical analysis result indicates that the calorific value ranges from 6,186 to 7,350 cal/g, the sulphur content is from 3% to 4.65% , fixed carbon ranges from 45.69 to 53,96%, and ash content from 7.86 - 16.37%. On the basis of those parameter, the coal within the Bobong Formation is categorized as subbituminous to high volatile bituminous rank.    
Mineralisasi pada batuan induk batugamping di daerah Lepadi, Dompu, Nusa Tenggara Barat Herman, Danny Zulkifli
Indonesian Journal on Geoscience Vol 3, No 3 (2008)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.3.3.175-182

Abstract

http://dx.doi.org/10.17014/ijog.vol3no3.20086Lepadi area situated in the Regency of Dompu, West Nusa Tenggara, is occupied by limestone unit comprising limestone and sandy limestones; and sandstones which are occasionally found as lenses within units of tuffaceous sand and tuff breccia. Indication of metallic mineralization is shown by the occurrence of the base metal-bearing quartz veins penetrating a host rock of limestone. A pervasive hydrothermal alteration was formed as chlorite-calcite- muskovite/sericite-quartz and kaolinite/haloysite series with veins consisting of massive quartz veinlets (millimeter to 2.0 cm maximum width) and very thick vuggy quartz veins (± 3.2 m width). The first quartz type contains ore minerals such as galena, sphalerite, chalcopyrite, pyrite and iron oxide; whilst the second type has a predominant galena content with an association of, chalcopyrite, covelite, pyrite and iron oxide which occurred as tiny vugs filling and distributed sporadically within the quartz body. The result of studies by using microscope (petrography and mineragraphy), infra-red analysis (PIMA), chemical analysis and fluid inclusion on entirely altered rock/ore mineral/quartz vein samples reveals that the alteration and mineralization processes might occur in a mineralization system involving hydrothermal fluid of near neutral at the temperature ranging from 275º - 200oC. It brings to a suggestion that deposition of quartz veins and associated ore minerals has taken place in a depth ranging from 620 – 150 m beneath paleosurface. It is based on hydrothermal fluid’s salinity ranging from 1.2 – 2.2 equivalent wt.% NaCl de- tected from fluid inclusion within quartz crystal samples.  
Litostratigrafi dan sedimentasi Formasi Kebo dan Formasi Butak di Pegunungan Baturagung, Jawa Tengah Bagian Selatan Surono, Surono
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.3.4.183-193

Abstract

http://dx.doi.org/10.17014/ijog.vol3no4.20081Lithologically, the Nampurejo Pillow Lava, Kebo and Butak Formations, which are dominated by volcanic rocks, spread west - eastly, along the northern foot of the Baturagung Mountains. The Nampurejo Pillow Lava, which has an Early Oligocene age, is overlain by the Late Oligocene - Early Miocene Kebo and Butak Formations successively. The Nampurejo Pillow Lava consists of basaltic pillow-lavas showing pillow structures and they are intercalated by black sandstones. The Kebo Formation comprises alternating sandstone and pebbly sandstone with intercalations of siltstone, claystone, tuff, and shale. On the other hand, the Butak For- mation is composed of polymic breccia with intercalations of sandstone, pebbly sandstone, claystone, and siltstone/shale. The three units were deposited in a deep – shallow marine basin, which was filled by volcanic prod- ucts. Compared to the lower part of the Kebo Formation, volcanic activities during the deposition of the upper part of the Kebo Formation and the Butak Formation were more active.    
Micromorphological Characterization of Some Volcanic Soil In West Java Arifin, Mahfud; Devnita, Rina
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.3.4.195-203

Abstract

http://dx.doi.org/10.17014/ijog.vol3no4.20082Micromorphological characterization has been studied on six pedons of soils developing in volcanic materials in West Java. The pedons represent deposits of different volcanoes (Mount Tangkuban Perahu, Mount Patuha and Mount Papandayan) with different ages (Pleistocene, Holocene) within two types of volcanisms (andesitic, basaltic), and three agroclimatic zones (A, B1, B2). Undisturbed soil samples were taken from each identifiable horizon for thin section preparations. Observations were carried out by means of a magnifying lens, binocular stereomicroscope, polarization microscope, and scanning electron microscope (SEM). The result demonstrates that micromorphological characteristics of volcanic soils developing from different ages, types of parent material, and climate were different through their c/f related distribution 2µ patterns, c/f ratios, sorting, infillings and coatings of voids, and microstructure.  
Potensi air tanah di cekungan air tanah Sambas, Provinsi Kalimantan Barat Hidayat, Robi S.
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.3.4.205-216

Abstract

http://dx.doi.org/10.17014/ijog.vol3no4.20083The grouping of the groundwater potential of Sambas area using the quantity and quality matrix of those groundwater can be divided into three classes. First, high groundwater potential area distributed in the Jawai, Teluk Keramat, Sejangkung, and Sakura Sub-regencies. Second, the moderate groundwater potential area covers the Sambas and Tebas Sub-regencies. Third, the low groundwater potential area cov- ers the Sanggauledo and Seluas  Sub-regencies.  

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