Journal of Geoscience, Engineering, Environment, and Technology
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Groundwater Quality Assessment for Drinking Purpose Based on Physicochemical Analysis in Teluk Nilap Area, Rokan Hilir, Riau, Indonesia.
Get PDFGroundwater is water resource that widely used for domestic purposes, including for drinking. However, the industrial and population growth causes the quality and quantity of groundwater to decline. In this case, the quality of drinking water in Indonesia must meet the requirements according to Health Minister Regulation No.492/MENKES/PER/IV/2010. This study aims are to determine the quality of groundwater in the research area based on physicochemical parameters and its evaluation for drinking water. Groundwater samples were taken from dug wells in Teluk Nilap area, Rokan Hilir, Riau. Groundwater samples have temperature average 30oC, TDS average 312,5 mg/L and pH average 5,6. Groundwater contain sulfate and nitrate with average value 48,8 mg/L and 11,86 mg/L, respectively. Groundwater water also have iron and lead metal above the permitted standard with average value 2,57 mg/L and 0,022 mg/L. Groundwater in the study is not recommended as drinking water
Analysis of the Surface Subsidence of Porong and Surrounding Area, East Java, Indonesia based on Interferometric Satellite Aperture Radar (InSAR) Data.
Get PDFSince 2006, the mud volcano erupted in the Porong area due to wellbore failure triggered by an earthquake (2006) epicenter in the Jogjakarta area. The mud volcano buried several villages with mud and continued erupted until today. Based on the InSAR data, it can be seen that the subsidence is still happening near the dam area and another area that is not related to mud volcano eruption such as the production of two gas fields in the Porong area. Moreover, the Porong area is flat and low, less than 4 meters above sea level. The analysis shows that the subsidence rate in this area is up to 0.5 m/yr. If this subsidence is continuing, the city can be sinking and flooding during the rainy season. The prediction result from this method is about 10 years more and 36 years since in 2006 based on the mudflow rate method
Geology and Mineral Potential of Copper-Silver mineralization in Kulu district of Himachal Pradesh, India.: Copper and silver deposits in Himachal Pradesh
No full textNaraul Formation of the Larji Group in Kulu district of Himachal Pradesh contains the major strata bound Copper mineralization at many places as observed through old working near Naraul, Danala and Kanda in Sainj Valley of Kulu district exposing the Proterozoic Northwestern Himalayan belt. The same structural belt is also known for Silver mineralisation around Manikaran. At Naraul, a regional stratigraphic and mineralogical framework of the Naraul Formation for mineralogical resource assessment was viewed. The old workings within 4-5 km long and 200-300m wide along the NW- SE trending structural trend cover the main ore potential zones. The ore mineralisation seems to be alike the copper silver deposit of the Revett Formation of Montana and Idaho, USA. The deposit in Naraul needs further more drilling investigation and exploration for actual reserve assessment.  
Alteration Alteration, Mineralization and Geochemistry of Metamorphic Rocks Hosted Hydrothermal Gold Deposit at Rumbia Mountains, Bombana Regency, Southeast Sulawesi, Indonesia
No full textIn Indonesia, gold is commonly mined from porphyry, epithermal and skarn type deposits that are commonly found in volcanic/magmatic belts. However, were recently numerous gold prospects discovered in association with metamorphic rocks. This paper is intended to describe an alteration and ore mineralogy hosted by metamorphic rocks at Rumbia mountains, Bombana regency, Southeast Sulawesi province, Indonesia. The study area is found the placer and primary gold hosted by metamorphic rocks. The placer gold is evidently derived from gold-bearing quartz veins hosted by Pompangeo Metamorphic Complex (PMC). This study is conducted in three stages, three stages including desk study, field work and laboratory analysis. Desk study mainly covers literature reviews. Field work includes mapping of surface geology, alteration and ore mineralization as well as sampling of representative rocks types, altered rocks and gold-bearing veins. Laboratory analysis includes the petrologic observation of handspecimen samples, petrographic analysis of the thin section and ore microscopy for polished section, XRD (X-ray diffraction), ICP-AES (Inductively Coupled Plasma Atomic Emission Spectroscopy), ICP-MS (Inductively Coupled Plasma Emission Mass Spectrometry and FA/AAS (Fire Assay/Atomic Absorbtion Spectophotometry) analysis. The results shows that the alteration characteristics of hydrothermal gold deposits in Mendoke and Rumbia mountain consist of 3 (three) alterations namely sericitic, argillic dan propylitic. Characteristics of mineralization hydrothermal gold deposits in the research area are generally p related to gold-bearing quartz veins/veinlets consist of chalcopyrite, pyrite, chrysocolla, covellite, cinnabar, magnetite, hematite and goetite in rocks categorized into greenschist facies. There are three generations of veins identified including the first is parallel to the foliations, the second crosscut the first generation of veins/foliations, and the third is of laminated deformed quartz+calcite veins at the late stage. The quartz veins commonly deformed, segmented, massive, laminated, irregular, brecciated, and occasionally sigmoidal. The veins contain erratic gold in various grades from below detection limit <0.0002 ppm to 18,4000 at found in third generation veins which are laminated quartz±calcite in argillic alteration. ppm. The protoliths of metamorphic rocks in Rumbia Mountain, which comes from sedimentary rocks, spesifically pelitic rocks and graywacke. Based on those characteristics, it obviously indicates that the primary gold deposit present in the study area is of orogenic gold deposits type. The orogenic gold deposit is one of the new targets for exploration in Indonesia
Adaptation to the Climate Change Impact through Community Participation on Customary Land Use
Get PDFClimate Change and global warming have brought some policy to reduce the impacts by adaptation and mitigation strategies. One adaptation strategy is to increase land use size in agriculture area base on community participation. On the other hand, sustainable development needs cooperation mainly on common investment. The aim of the study is to identify the land utilization process, role model and level of participation on customary land. We use observation and deep interview method to analyze this study. The result shows that the customary land utilization process has realized through public deliberation with local Fig.s. The agriculture programs operated with Wanatani concept or agro-forestry by housewives where multi-level strategy is mutually beneficial. Around 30 housewives have been participating in producing agriculture products, i.e., coffee, milk candy, palm sugar, and ginger powder. The level of participation especially for female farmers at RW 01, which shows a percentage of 16.6%. Generally, community participation has encouraged the gotong-royong model while has to contribute in their time, tools and materials to develop the communal shed. In conclusion, the land tenure system has taken with sharing benefits between local government & farmers. The customary tenure has recognized as one of the tenure systems in Indonesia, especially on Adat land management
Evaluation of the Hydrocarbon Potentials of Shale Exposures at Okpekpe in Edo North
Get PDFThis study evaluates the source rock characteristics of rock exposures along a newly exposed road cut in Okpekpe. An integrated technique of organic geochemical analysis and biostratigraphy evaluation were adopted to determine the source rock quality, Maturation index, kerogen types, depositional environment andsediment age.
Results of organic geochemistry gave total organic carbon (TOC) value between 0.81 to 3.04 w.t% (2.08wt.% average) indicative of a good source potentials. The plot of Total Sulphur Content (TSC) against TOC suggests a transitional depositional environment for the samples while the plot of hydrogen index (HI) against oxygen index (OI) shows that the samples are capable of generating mixed type II/III kerogen.
Palynological analysis revealed that the basal section of the exposure is characterized by the occurrences of typical and moderately rich Late Cretaceous – Early Tertiary palynomorphs. While the upper section is poorly rich in palynomorph abundance but with spot occurrences. The palynomophs asssemlages is of Late Maastrichtian - Early Paleocene and the outcrop is characterized by the presence of terrestrial pollens and spores indicating a continental to transitional depositional environment, typical of the Mamu Formation of the Anambra Basin
Petrogenesis of Volcanic Arc Granites from Bayah Complex, Banten, Indonesia
Get PDFThis research aimed to reveal the petrogenesis of granitic rocks of Bayah Complex starting from magma differentiation to exposing event, this research also intended to determine the tectonic environment. The methods carried out in this research include field observation, petrographic analysis using polarized light microscopy, and geochemical analysis using X-Ray Fluorescence (XRF) and Inductively Coupled Mass Spectrometry (ICP-MS).
Petrographic analysis shows that Bayah granitic rocks are composed of quartz, plagioclase, and K-feldspar while the rest are amphibole, biotite, sericite, chlorite, epidote, and opaque. Based on its major oxide concentrations, Bayah granitic rocks classified as granite and diorite-quartz which have high-K calc-alkaline magma. 4 samples of granitic rocks showed the A/N+K+C > 1 molar ratios belonging to the peraluminous S-type granite index while the remaining 1 sample showed a molar ratio of A/N+ K+C < 1 and A/N+K > 1 which classified as metaluminous I-type granite. Accordingly, Bayah granitic rocks are S-type granite which crystallized from sediment-derived magma, the sediments itself estimated sourced from continental especially Malay Peninsula, Indonesian Tin Island, and Schwaner Mountains. During differentiation, the magma undergone crustal contamination reflected by the increase in both SiO2 0.51 wt% and Al2O3 1.95 wt%, and decrease in Fe2O3 + MgO 0.61 wt% from the pure composition of sediment-derived magma. Furthermore, the occurrence of crustal contamination also recognized from high concentrations of Rb and Ba which indicate the interaction of magma with the materials of continental crust.
Regard to the exposing event, Bayah granitic rocks approximated to be exposed due to regional tectonic activity which caused Orogenesa I in the Early Oligocene to the Late Oligocene. Moreover, based on the plot of trace elements especially Rb, Y, Nb, Ta, and Yb on Harker and tectonic discriminant diagrams, Bayah granitic rocks are formed on volcanic-arc active continental margins in accordance with regional tectonic setting.  
Geometric and strain analyses in folds of the area around Gankot, district Pithoragarh, Uttarakhand, India
Get PDFThe study area around Gankot in Pithoragarh district of Uttarakhand belongs to the Thalkedar Limestone unit of Mandhali Formation, Tejam Group in Inner Sedimentary Zone of Lesser Himalaya, which exposes complexly folded and refolded structures. Geometric analysis carried out on the profile section of the fold tracing using dip isogon and orthogonal thickness parameters revealed presence of all the fold geometry suggested by Ramsay (1967) however the class 3 followed by class 1B are the most dominant classes in the study area when individual layers of the fold were studied. The study of folds as multilayered unit reveals that folds in study area belong to strongly non-analogous fold class of anisodeviatoric folds. In fold, the strain analysis has been done by drawing strain ellipse obtained by Inverse Thickness Method which is useful in estimating flattening strain even when the flattening is imposed obliquely to the fold’s axial trace. The finite two-dimensional flattening strain ratio (Rs) value ranged between 1 and 3.14 with an average Rs value of 1.60. The method of Srivastava and Gairola (2003) has also been used to obtain shear strain and flattening strain for the multilayered folds of study area. The results reveal that the multilayered folds around Gankot area are moderately flattened with mean flatting strain varying between 1.06 and 2.28. A very high degree of variation in shearing ranging about 70o in both clockwise and anticlockwise directions has been noticed. The shear strains (γ) in folds have been found to vary between -2.75 to + 3.27 with an average of +0.33. The shearing and strain patterns are suggestive that the most dominant folding mechanism has been the flexure-shear for the folds of the study area which are overprinted by the fold flattening and other subsequent deformations
An Integrated Approach in Geophysical Investigation of Road Failure in Crystalline Basement Area of Nigeria
No full textThe result of the geophysical investigation carried out to access the cause of road failure and remediation measures along Ilesha-Osogbo expressway, Osun State, South-western Nigeria is presented. The study involved integrating the dipole-dipole technique of electrical resistivity method with the ground penetrating radar (GPR) method. Two dipole-dipole traverses, one long and 20 short GPR profiles were established across the failed section of the road. The dipole-dipole data were interpreted using the Diprowin software to produce the pseudo-section while the GPR data were interpreted using the RadProwin to produce the radargram. The result revealed that the failed road exhibit incompetent layer of resistivity values ranging between 17 Ωm to 171 Ωm lying between two competent layers of resistivity values greater than 200 Ωm. A combination of the dipole-dipole technique and the GPR techniques revealed the depth extend to failure to about 4.5 meters to 5 meters deep which overlie a basement rock of undifferentiated gneiss, a rock that is easily prone to weathering. The water level was observed to occur at shallow depth of about 2 meters and infiltrates the entire weathered layer. The shallow groundwater level coupled with the water-logged clayey layer derived from the weathered materials from basement rock were found responsible for the failure of this section of the road. The study recommends the excavation of the waterlogged clayey layer to a depth of about 5 to 6 meters deep into the subsurface and replacement first with heavy boulders of granitic materials and later overlaid with a thick layer of highly resistive landfill materials such as laterite. The result of the two techniques used in this work have proved to be supportive due to the integration of the double dipole technique with the GPR technique, a relatively new technique recently being introduced into road failure mapping
Tidal Ellipses Analysis Based on Flow Model Hydrodynamic Data Acquisition in Mandeh Bay, West Sumatera
Get PDFMandeh Bay is threatened by sedimentation issue caused by the rapid development of marine tourism area which strongly impacts to the environmental degradation. Due to the semi-enclosed area of Mandeh Bay, the tidal current has a significant role in triggering vertical and horizontal transports within the bay. This study aimed to determine the characteristic of tidal current during the southwest monsoon. We developed a hydrodynamic model based on Navier-Stokes equations using a flexible mesh and tidal forecast in which the validation is performed by ADCP data. The simulation results will be used as the basic data to develop a model which depicts the elliptical pattern of tidal current constituents. Offshore rotary tidal currents which are originally semidiurnal reiterate the elliptical pattern every 6 hours and 12 minutes. The strongest semidiurnal current speeds are observed in the bay mouth ranged from 0.1-0.5 m.s-1. The tidal constituent ellipses are oriented more meridionally and in several areas oriented zonally. The current speed of is the highest at all which the speed is averagely one third of magnitude. While, the two main diurnal tidal constituents ( and ) have the maximum speeds approximately one fifth of magnitude. Thus, the domination of semidiurnal constituents may trigger sediment distribution and accumulation within the bay because of its twice tidal oscillations entering the bay