scholarly journals Petrography, Geology Structure and Landslide Characterization of Sumatra Fault Deformation: Study Case In Km 10-15 Highway, Koto Baru Sub District, West of Sumatra

2018 ◽  
Vol 3 (4) ◽  
pp. 192 ◽  
Author(s):  
Catur Cahyaningsih ◽  
Puja Fransismik Crensonni ◽  
Yogi Aditia ◽  
Adi Suryadi ◽  
Yuniarti Yuskar ◽  
...  
Keyword(s):  
Debris Avalanche ◽  
Research Area ◽  
Geological Mapping ◽  
Geological Condition ◽  
Translational Landslide ◽  
West Sumatra ◽  
Fault Deformation ◽  
Study Case ◽  
Geological Analysis

Research area is around Tanjung Balik, Koto Baru Sub Base, Lima Puluh Kota District, West Sumatra Province. Located along the highway Km 10-15 Riau – West Sumatra and the coordinate around 00˚08'40 '' LU - 0˚11'20 '' N and 100˚45'20 '' BT - 100˚47'00 '' BT. The purpose of research to identify petrography, microstructure, types of landslides and the geological condition. The methods using polarization microscope, stereography, landslide identification survey and geological mapping. The result of study shows the petrography analysis of lithology of study area are classified into three types of rocks are Feldspathic Greywacke, Lithic Arenite, and Slate. Microstructures trending system show the foliation structure that is relatively Southeast-Northwest. Types of landslide which dominates in the research area are debris avalanche and translational landslide. Geological analysis show some of rock units are classified into two units: Sandstone Unit and Slate Unit. Sandstone Unit spread in the northern part of the study area, while Slate Unit spread in the southern part of the study area. The characteristics of these rocks showed Pematang Formation.

scholarly journals Geology and Petrogenesis of Igneous Rocks from Batur Paleovolcano, Gunungkidul, Yogyakarta: Evidence from their Textures, Mineralogy, and Major Elements Geochemistry

2019 ◽  
Vol 4 (1) ◽  
pp. 32
Author(s):  
Fahmi Hakim ◽  
Yanuardi Satrio Nugroho ◽  
Cendi Diar Permata Dana ◽  
Anastasia Dewi Titisari
Keyword(s):  
Tectonic Setting ◽  
Research Area ◽  
Major Elements ◽  
Geological Mapping ◽  
Igneous Rocks ◽  
Emission Spectrometry ◽  
Geochemical Data ◽  
Geological Condition ◽  
Calc Alkaline ◽  
Andesite Lava

Batur paleovolcano is located in Wediombo Beach area, Gunungkidul Regency, Yogyakarta and is being part of Wuni Formation. Several volcanic products including lava flow, autoclastic breccia and volcanic breccia can be found associated with diorite intrusions. This research is aimed to characterize geological, mineralogical andgeochemical variations of igneous rocks from Batur paleovolcano to understand its petrogenesis. Detailed geological mapping with scale of 1:12,500 is conducted to identify geological aspects and delineate igneous rocks distributions. Igneous rocks and selected wall rocks samples were prepared for laboratory analysis including 8 samples for petrography and 5 samples for ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry) analysis. Several geochemical data from previous study are also added to investigate the geochemical variations. Geological condition of the research area consists of four rock units including colluvial deposit, limestone, andesite lava and diorite intrusion. Geological structures found are normal fault and shear joint where the main stress direction is north–south. Petrography analysis showed that igneous rocks in this research area consist of diorite intrusion and andesite lava with phorphyritic texture. Plagioclase become the most abundant minerals found both as phenocryst phase and groundmass. Hornblende only occur as phenocryst phase in minor amounts as accesory mineral. Major elementsgeochemistry analysis showed the rocks are characterized by intermediate silica with low alkali content. They are can be categorized as calc-alkaline series. However, some samples are fall into tholeiitic series. Major elements variation and textural study also indicate the magma is experienced differentiation process by fractional crystallization mechanism. This study suggests that igneous rocks from Batur paleovolcano is formed by two phases of formation. Earlier phase is the formation of andesite lava in island arc tholeiitic tectonic setting then at the later phase is formation of diorite intrusion in the calc-alkaline basalts tectonic setting.

scholarly journals Policy Direction on Driving Population for Reducing Poverty in the West Sumatra Province

2021 ◽  
Vol 5 (10) ◽  
pp. 17-21
Author(s):  
Tegus Widodo ◽  
Iswandi Umar ◽  
Ramadhani . ◽  
Suhatman .
Keyword(s):  
Population Control ◽  
Linear Regression Analysis ◽  
Secondary Data ◽  
Control Policy ◽  
Research Area ◽  
Poor People ◽  
Marriage Age ◽  
Number Of Children ◽  
West Sumatra ◽  
Policy Direction

Reducing poverty is always to become the target of every country and regional leader in each campaign. The efforts are made in many ways, but the programs in the form of providing basic needs assistance, productive economic efforts, and so on. Unfortunately, interventions are to address visible symptoms but not to solve the root of the problems or causes. That is because the cause of poverty is not so excavated so that until now the percentage of the poor always fluctuates. This research tries to see in terms of the number of children (TFR) that may have contributed to the percentage of poor people in West Sumatra. The research method uses linear regression analysis using secondary data from Susenas 2019. To determine policy direction using Interpretative Structural Modeling (ISM) analysis. The ISM analysis involved 15 relevant stakeholders from interested institutions. The results showed that TFR contributed 34.4 percent to poverty in the research area. As a direction of population control policy to reduce poverty, that is the expansion of access to contraceptives and delay of marriage age.

scholarly journals Characterization of secondary deposits of columbite-tantalite minerals found in the city of Rorainópolis (RR), Brazil

2020 ◽  
Vol 8 (4) ◽  
pp. 450-468
Author(s):  
Anna Caroline Andrade Pinto ◽  
Tiago Felipe Arruda Maia
Keyword(s):  
Scientific Community ◽  
Research Work ◽  
Geological Mapping ◽  
Mineral Deposits ◽  
X Ray Diffraction ◽  
X Ray ◽  
Source Areas ◽  
The City ◽  
Petrographic Description

Many of the studies about mineral deposits are bringing great information to the scientific community, providing, for example, general characteristics of these deposits, possible source areas and its used in some cases as prospective tools to help in geological mapping. In this way, this study aimed to characterize the alluvial secondary deposits of columbite-tantalite that were found near vicinal 12, about 50km north/northeast of Rorainópolis city, between the BR-174 and BR-210 roads, in the state of Roraima (Brazil), bases on 4 samples that were brought by a resident of the region. To fulfill these objectives, some chemical and mineralogical methods were performed, like: magnetic separation, X-ray diffraction, X-ray fluorescence and petrographic description. The deposits of the region end up being characterized by having a large amount of Fe and Ti (mostly), containing in some places also a large concentration of Niobium and Tantalum. Not all samples have columbite-tantalite, showing that their concentration in some areas of the deposit is quite low. There are samples with less than 1% Nb and Ta and also samples with more than 20% Nb and 6% Ta concentration. These minerals were poorly transported, being identified by the degree of roundness and granulometry of the samples. A weathering cap on some minerals could also be verified. This research work turned out to be relevant, as it provides new data that add to the knowledge of the mineral potential, which has not been fully explored yet.

scholarly journals NUMERICAL EVALUATION OF TUNNEL PORTAL SLOPE STABILITY AT BAGONG DAM SITE, EAST JAVA, INDONESIA

2020 ◽  
Vol 5 (1) ◽  
pp. 40
Author(s):  
Irien Akinina Fatkhiandari ◽  
I Gde Budi Indrawan, Dr.
Keyword(s):  
Slope Stability ◽  
Research Area ◽  
Poor Quality ◽  
Geological Mapping ◽  
Residual Soil ◽  
Volcanic Breccia ◽  
Earthquake Load ◽  
Dam Site ◽  
Tunnel Portal

Geometries of excavated tunnel portal slopes at Bagong Dam site was initially designed without taking into account earthquake load. The excavated slope designs also assumed the rocks consisting the slopes were homogenous. The purpose of this research was to evaluate stability of the excavated tunnel inlet and outlet slopes at the Bagong Dam site under static and earthquake loads using finite element method. Stability of the natural slopes was also analyzed for comparison. The numerical static and pseudostatic analyses of slope stability were carried out using RS2 software (Rocscience, Inc.). Input data used in the numerical analyses were obtained from engineering geological mapping, rock core analyses, and laboratory tests. Seismic coefficient applied in the pseudostatic slope stability analyses was determined following guideline described in Indonesian National Standard. The engineering geological mapping and evaluation of rock cores indicated that the inlet tunnel slope consisted of four types of materials, namely residual soil, poor quality of volcanic breccia, very poor quality of volcanic breccia, and good quality of volcanic breccia. The outlet portal slope consisted of six types of materials, namely residual soil, very poor quality of limestone, poor quality of limestone, very poor quality of volcanic breccia, poor quality breccia, and good quality breccia. Based on the secondary elastic wave velocity (Vs) values, the rock masses in the research area were classified as hard rock (SA). Seismic analyses based on the earthquake hazard source map with 10% probability of exceedance in 50 years provided by the National Earthquake Center (2017) indicated that the PGA and the corresponding amplification factor FPGA in the research area were 0.3 and 0.8, respectively. The calculated seismic coefficient for the pseudostatic slope stability analyses was 0.12. The numerical analysis results showed that, in general, earthquake load reduced critical Strength Reduction Factor (SRF) values of the slopes. However, the natural and excavated tunnel portal slopes were relatively stable under static and earthquake loads. The natural slope at the tunnel inlet with a 40° inclination had critical SRF value of 4.0, while that of at the tunnel outlet with a 51° inclination had critical SRF value of 2.6. Under static load, the excavated slopes at the tunnel inlet and outlet having a 45° inclination had critical SRF values of 2.4 and 5.0, respectively. Under earthquake load, the excavated slopes at the tunnel inlet and outlet had critical SRF values of 2.3 and 3.5, respectively.

Concise Review of Classical Guitar Modelling Technologies

2021 ◽  
Vol 11 (1) ◽  
pp. 25
Author(s):  
Alexandre M. Löw ◽  
Herbert M. Gomes ◽  
César M. A. Vasques
Keyword(s):  
Degrees Of Freedom ◽  
Research Area ◽  
Coupled Systems ◽  
Mode Shapes ◽  
Classical Guitar ◽  
Concise Review ◽  
Lumped Parameter ◽  
Basic Approaches ◽  
Shed Light

Analytical modeling and numerical simulation of multiphysics coupled systems is an exciting research area, even when it comes to intrinsically linear or linearized formulations, as is usually the case with coupled vibroacoustic problems. The combined effect of many localized geometrical miss-modeling with significant uncertainty in mechanical characterization of some organic materials yields large discrepancies in the natural frequencies and mode shapes obtained. The main goal of this work is to compare two basic approaches for the modeling of stringed musical instruments in the frequency domain: simplified lumped-parameter analytic modeling, considering only the most influential degrees of freedom, and discretized finite element modal analysis. Thus, the emphasis is on a review of some key references in this field, including previous work by the authors, which may shed light on some of the most relevant issues surrounding this problem.

scholarly journals Enhanced Characterization of the Krania–Elassona Structure and Functioning Allogenic Karst Aquifer in Central Greece

Geosciences ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 15 ◽  
Author(s):  
Antonios Manakos ◽  
Maria Ntona ◽  
Nerantzis Kazakis ◽  
Konstantinos Chalikakis
Keyword(s):  
Conceptual Model ◽  
Moving Average ◽  
Karst Aquifer ◽  
Groundwater Vulnerability ◽  
Spring Water ◽  
Geological Mapping ◽  
Spring Discharge ◽  
Water Type ◽  
Central Greece

The present study highlights the importance of geological, hydrogeological, and hydrogeochemical characterization of a karst aquifer in building a conceptual model of the system. The karst system of Krania–Elassona in central Greece was chosen for this application. Hydrogeological research included geological mapping and hydrogeological analysis. Additionally, hydrochemical analysis of water samples was performed in boreholes, rivers, and the system’s main spring. The Krania–Elassona aquifer consists of three horizons of marbles and is characterized by mature karstification. The karst aquifer is characterized by allogenic recharge mainly from the River Deskatis that accounts for up to 92% of the total flow. Groundwater and spring water are generally characterized as good quality and are suitable for irrigation and domestic use. The water type of the spring water is classified as Mg-HCO3. The application of a SARIMA (Seasonal Autoregressive Integrated Moving Average Model) model verified the conceptual model and successfully simulated spring discharge for a two-year period. The results of this study highlight the importance of basic hydrogeological research and the initial conceptualization of karst systems in reliably assessing groundwater vulnerability and modeling.

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