Tangkuban Perahu Research Articles

Melanic and Fulvic Andisols in Volcanic Soils derived from some Volcanoes in West Java

DOI: 10.17014/ijog.v7i4.149Melanic and fulvic Andisols are the great groups in the classification of volcanic soils Andisols, which describe the soils with high organic carbon content in the epipedon. The organic C must be more than 6% in the upper 30 cm with the value and chroma are 2 or less for melanic and more than 2 for fulvic. Melanic epipedon also has to have the melanic index that is 1.70 or less. The objective of this study is to investigate the melanic and fulvic Andisols in volcanic soils that developed under pine forest vegetation (Pinus merkusii) from different parent materials and ages of Mount Tangkuban Parahu (andesitic, Holocene) and Mount Tilu (basaltic, Pleistocene). The method used was a descriptive comparative survey of three profiles in Mount Tangkuban Parahu and three profiles in Mount Tilu. Analyses were done for each horizon in the profiles comprising the investigation of andic soil properties through the analyses of organic C, bulk density, Al + ½ Fe (ammonium oxalate), and P-retention. The investigations were continued by further calculation of organic C content and by investigation of soil colour with Munsell Soil Colour Chart. The results showed that the two profiles in Mount Tangkuban Parahu and two profiles in Mount Tilu are fulvic Andisol. No melanic Andisols were found in both locations. Pine forest vegetation encourages the formation of fulvic Andisols were derived from andesitic-Holocene parent materials or basaltic-Pleistocene parent materials.

Erysiphe Javanica sp. nov., a New Tropical Powdery Mildew from Indonesia

During the collection of tropical powdery mildews in Cibodas Botanical Garden and Mount Tangkuban Perahu in Indonesia, we found interesting specimens on Castanopsis javanica (Fagaceae). Phylogenetic analysis using a combination of 28S and ITS rDNA sequences clearly showed that this fungus forms a distinct lineage among the Erysiphe species found on hosts of the plant genus Castanopsis. Therefore, we consider this fungus a new species of Erysiphe, described here as Erysiphe javanica. Differences between E. javanica and closely related Erysiphe species are discussed. Mycotaxon, Vol. 120. Hal. 189-194 ISSN 0093-4666

Erysiphe javanica sp. nov., a new tropical powdery mildew from Indonesia

During the collection of tropical powdery mildews in Cibodas Botanical Garden and Mount Tangkuban Perahu in Indonesia, we found interesting specimens on Castanopsis javanica (Fagaceae). Phylogenetic analysis using a combination of 28S and ITS rDNA sequences clearly showed that this fungus forms a distinct lineage among the Erysiphe species found on hosts of the plant genus Castanopsis. Therefore, we consider this fungus a new species of Erysiphe, described here as Erysiphe javanica. Differences between E. javanica and closely related Erysiphe species are discussed.

Archaeal Life on Tangkuban Perahu-Sampling and Culture Growth in Indonesian Laboratories

The aim of the expedition to Tangkuban Perahu, West Java was to obtain archaeal samples from the solfatara fields located in Domas crater. This was one of the places, where scientists from the University of Regensburg Germany had formerly isolated Indonesian archaea, especially Thermoplasma and Sulfolobus species but not fully characterized. We collected five samples from mud holes with temperatures from 57 to 88 °C and pH of 1.5-2. A portion of each sample was grown at the University of Regensburg in modified Allen's medium at 80 °C. From four out of five samples enrichment cultures were obtained, autotrophically on elemental sulphur and heterotrophically on sulfur and yeast extract; electron micrographs are presented. In the laboratories of Universitas Indonesia the isolates were cultured at 55-60 °C in order to grow tetraetherlipid synthesizing archaea, both Thermoplasmatales and Sulfolobales. Here, we succeeded to culture the same type of archaeal cells, which had been cultured in Regensburg, probably a Sulfolobus species and in Freundt's medium, Thermoplasma species. The harvested cells are documented by phase contrast microscope equipped with a digital camera. Our next steps will be to further characterize genetically the cultured cells from Tangkuban Perahu isolates.

Degradation of keratin by keratinase and disulfide reductase from Bacillus sp. MTS of Indonesian origin

Abstract Bacillus sp. MTS isolated from Tangkuban Perahu crater Indonesia was found capable of degrading whole chicken feather effectively. The bacteria produced extracellular alkaline keratinase and disulfide reductase. When grown in feather media, Bacillus sp. MTS produced multi-fractions of both enzymes. The purified enzymes worked optimally at alkaline pHs, for keratinase at pH 8–12, and for disulfide reductase at pH 8–10. Optimum temperature for the extracellular keratinase was within 40–70 °C, while that for disulfide reductase was 35 °C. When the purified keratinase was mixed with purified disulfide reductase, enzyme activities on the natural keratin substrates (feather and wool) were greatly increased compared to activity of each enzyme alone, activity of proteinase K or activity of purified keratinase in the presence of reducing agents. The mutual action of the two enzymes on feather was examined by Scanning Electron Microscope.

INDUKSI DAN KONDUKSI GELOMBANG ELEKTROMAGNETIK AKIBAT SAMBARAN PETIR PADA JARINGAN TEGANGAN RENDAH

Induction and Conduction Electromagnetic Waves Caused by Lightning Strike on the Low Voltage Network. Direct and indirect lightning strikes can disturb and induce low voltage overheadlines and it can produced overvoltage due to traveling waves along the lines. This overvoltage can damage the equipments connected to it. It was recorded that there were already a lot of damages of electronic equipments and arrestesr located inside the building of Lightning Measurement Station at Mnt. Tangkuban Perahu. Most of the overvoltage which was developed on the low voltage lines were coming from indirect lightning strike nearby due to the fact that most of the lines were covered by trees. Research was carried out to study and evaluate the induction and conduction of the lightning strikes to the LV lines that can lead to the cause of equipment and arrester damages inside the building. Local lightning data for the analysis were derived from measurement system installed at the stations and historical lightning data from lightning detection network called Jadpen (National Lightning Detection Network). The data was used for calculating and evaluating the voltage elevation, induction voltage profiles and conduction in the form of traveling waves using Rusck Model. Two damaged arresters were evaluated and compared and it give the better understanding on how the protection system work.

GROUNDWATER FLOW SYSTEM OF BANDUNG BASIN BASED ON HYDRAULIC HEAD, SUBSURFACE TEMPERATURE, AND STABLE ISOTOPES

To recognize the groundwater flow system in the Bandung Basin, two main methods of regional groundwater flow delineation were employed: hydraulic heads and tracers. Two different environmental tracers, i.e. subsurface temperature and stable isotope were applied. The measured temperatures and stable isotope compositions from 19 observation wells lead to the recognition of three types of flow systems within the Bandung Basin i.e., shallow, intermediate and deep groundwater flow system. The recharge area is located in the hills and upland which form the periphery of the plain. The summit area of the southern mountainous complex might have represented the highest recharge area No indication was found for water being recharged at higher elevation in the northern part of the basin which means the recharged water in the Mount Tangkuban Parahu area did not reach the Bandung Plain. This study clearly demonstrates the usefulness of these environmental tracers and hydraulic head measurement in identification of the groundwater flow system of a certain area.

Geology, Age Dating and Geochemistry of the Tangkuban Parahu Geothermal Area, West Java, Indonesia

Geology, Age Dating and Geochemistry of the Tangkuban Parahu Geothermal Area, West Java, Indonesia

Structural geology controls on groundwater flow: Lembang Fault case study, West Java, Indonesia

Field evidence has shown that Lembang Fault (West Java, Indonesia) can act as a groundwater flow barrier. There are outcrops along the footwall comprising consolidated brecciated rock with very low permeability, springs and hot springs occurring along down-thrown hanging-wall rock adjacent to the fault, and a high permeability layer of old and young Tangkuban Parahu eruptive materials (hanging wall) juxtaposed against the low permeability of the older volcanic layer of Bukit Tunggul unit (footwall). Two different environmental tracers were utilized in the study: electrical conductivity measurement and stable isotope analysis. Hydraulic head was measured at some wells along the fault and water electrical conductivity measurements were carried out in a small catchment, the upper part of Cikapundung River basin, which is located just north of Bandung City. Water samples for stable isotope composition analysis were taken from 19 observation wells distributed randomly inside the basin. All analysis data lead to the recognition that Lembang Fault blocks the groundwater flow. No indication was found for water being recharged at higher elevation in the northern part of Bandung Basin, which means the recharged water in Mount Tangkuban Parahu area does not reach Bandung Plain.

Micromorphological Characterization of Some Volcanic Soil In West Java

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.

Temporal chemical variations in late Cenozoic volcanic rocks around The Bandung Basin, West Java, Indonesia.

The Bandung Basin is located on axis of the Sunda arc in the West Java, Indonesia. This basin is underlain by dominant late Cenozoic volcanics. Lava samples were corrected from Quaternary Sunda and Tangkuban Perahu volcanoes and volcanics underlying these. Age of the lavas have been dated by K-Ar method to be ca. 4.1 Ma-ca. 0.04 Ma. Lavas are basalt to dacite in composition, and SiO2 contents range 51-63 wt.%. Both tholeiitic and calc-alkaline suites exist, and K2O 1evel covers medium-K to high-K suites. We used trace element for the estimation of primary basalt compositions. Model calculations using primary magma incompatible element contents examined the degree of partial melting of the source mantle occurred over the life of the suites. Continuous cooling of the mantle wedge was estimated, and a resurgence of degree of melting seems to have occurred between ca. 1.1 and ca. 0.6 Ma. Axial uplift took place in the Sunda arc during the period. This tectonic event may have been induced by a kinematic change in the subduction of the Indian-Australian Plate beneath the Sunda arc, which also affected the melting state of the upper mantle beneath the area.

A chronology for geomorphological developments in the greater Bandung area, West-Java, Indonesia

The greater Bandung area (West-Java, Indonesia) is a large intramontane basin surrounded by volcanic highlands. Geomorphological and sedimentological studies reveal that the morphology of the central basin and the Sunda-Tangkuban Perahu volcanic complex developed during the Middle-Late Quaternary, in particular since 125 kyr B.P. Tectonic subsidence, paroxysmal eruptions, volcanism-induced faulting/rifting, drainage system adaptations and intramontane lacustrine sedimentation (partly geomorphology-controlled) constitute the dominant landform-determining processes. A reconstruction of the regional morphological development is based on interpretation of morphological features and morphodynamic processes in the volcanic upland, in combination with analysis of the sedimentary record in the basin. A chronological framework is based on datings obtained from surficial sediments and deep drill cores. Initially, long term patterns in volcanicity and tectonic effects determine regional sedimentation and relief development in the greater Bandung area. Fluvial sedimentation and weathering prevailed in the basin, while the southern and northern volcanic ranges gradually formed. Basin subsidence, with contemporaneous volcanism around 125 kyr B.P., resulted in the formation of an enclosed intramontane basin, and stimulated lacustrine sedimentation. From this time on, concentration of volcanicity in the northern Sunda-Tangkuban Perahu complex and the resulting morphostructural developments caused rapid (catastrophic) and localized morphological changes. Cataclysmic eruptions (around 105 kyr B.P. and 50-35 kyr B.P.) caused voluminous sediment inflow in the northwestern basin. These events mark the significance of the Sunda-Tangkuban Perahu volcanic centre during the Late Quaternary; the Sunda volcano collapsed into a caldera in which later the Tangkuban Perahu volcano developed. Moreover, these eruptions controlled regional sedimentation and determined landform development in the greater basin area. In the vicinity of the eruption centre, volcano-tectonic faulting formed the conspicuous E-W Lembang fault that controlled distribution of volcaniclastic sediments and the initiation of a new drainage system in the Lembang area. In the low-lying Bandung plain persistent (fluvio)lacustrine and volcaniclastic sedimentation, followed by basin subsidence and minor fluvial erosion characterised the younger phases of landform development.

PV32 インドネシア・タンクバンプラフおよびグンツール火山における ELF-MT 測定

PV32 インドネシア・タンクバンプラフおよびグンツール火山における ELF-MT 測定

Recent uplift and hydrothermal activity at Tangkuban Parahu volcano, west Java, Indonesia

Tangkuban Parahu is an active stratovolcano located 17 km north of the city of Bandung in the province west Java, Indonesia. All historical eruptive activity at this volcano has been confined to a complex of explosive summit craters. About a dozen eruptions-mostly phreatic events- and 15 other periods of unrest, indicated by earthquakes or increased thermal activity, have been noted since 1829. The last magmatic eruption occurred in 1910. In late 1983, several small phreatic explosions originated from one of the summit craters. More recently, increased hydrothermal and earthquake activity occurred from late 1985 through 1986. Tilt measurements, using a spirit-level technique, have been made every few months since February 1981 in the summit region and along the south and east flanks of the volcano. Measurements made in the summit region indicated uplift since the start of these measurements through at least 1986. From 1981 to 1983, the average tilt rate at the edges of the summit craters was 40–50 microradians per year. After the 1983 phreatic activity, the tilt rate decreased by about a factor of five. Trilateration surveys across the summit craters and on the east flank of the volcano were conducted in 1983 and 1986. Most line length changes measured during this three-year period did not exceed the expected uncertainty of the technique (4 ppm). The lack of measurable horizontal strain across the summit craters seems to contradict the several years of tilt measurements. Using a point source of dilation in an elastic half-space to model tilt measurements, the pressure center at Tangkuban Parahu is located about 1.5 km beneath the southern part of the summit craters. This is beneath the epicentral area of an earthquake swarm that occurred in late 1983. The average rate in the volume of uplift from 1981 to 1983 was 3 million m3 per year; from 1983 to 1986 it averaged about 0.4 million m3 per year. Possible causes for this uplift are increased pressure within a very shallow magma body or heating and expansion of a confined aquifier.

Geophysical events

This is a summary of SEAN Bulletin, 8(10), October 31, 1983, a publication of the Smithsonian Institution's Scientific Event Alert Network. The entire Veniaminof, Villarica, and Tangkuban Parahu reports are included; the Costa Rica and Una Una reports are excerpts. The complete bulletin is available in the microfiche edition of Eos as a microfiche supplement or as a paper reprint. For the microfiche, order document E83‐011 at $2.50 (U.S.) from AGU Fulfillment, 2000 Florida Avenue, N.W., Washington, DC 20009. For the paper reprint, order SEAN Bulletin (giving volume and issue numbers and issue date) through AGU Separates at the above address; the price is $3.50 for one copy of each issue number for those who do not have a deposit account, $2 for those who do; additional copies of each issue number are $1. Subscriptions to SEAN Bulletin are available from AGU Fulfillment at the above address; the price is $18 for 12 monthly issues mailed to a U.S. address, $28 if mailed elsewhere, and must be prepaid.