1,720,976 research outputs found
Uniqueness Deposit of Sediment on Floodplain Resulting From Lateral Accretion on Tropical Area
No full textKampar rivers has a length of 413 km with average depth of 7.7 m and width of 143 m. Sixty percent of this rivers are meandering fluvial system which transport and deposit a mixture of suspended and bed-load (mixed load) along low energy. River channel that moving sideways by erosion is undergoing lateral migration and the top of the point bar becomes the edge of the floodplain and the fining-upward succession of the point bar will be capped by overbank deposits of Kampar River. Along the Kampar Rivers, there are more than 60% of floodplain sediments and almost all of the floodplain formed by bend migration on the suspended-load channels of Kampar watershed. This formation consist of succession of fine to medium sand and silt/mud, with root traces, that form as drapes on the prograding bank. These beds dip mostly channel wards and quickly wedge out as they grade up and onto the floodplain. The depositional model is presented showing how lateral accretion can make a significant contribution to the preservation of fine-grained within channel deposits in contemporary floodplains. The examples presented here demonstrate that analogues to ancient point-bar deposits containing alternating sandstone and shale sequences are common in the low-energy fluvial environments of Riau rivers especially Kampar rivers.</jats:p
Sedimen Deposit of Floodplain Formation Resulting From Lateral Accretion Surfaces on Tropical Area: Study Case at a Kampar River, Indonesia
Get PDFKampar rivers has a length of 413 km with average depth of 7.7 m and width of 143 m. Sixty percent of this rivers are meandering fluvial system which transport and deposit a mixture of suspended and bed-load (mixed load) along low energy. River channel that moving sideways by erosion is undergoing lateral migration and the top of the point bar becomes the edge of the floodplain and the fining-upward succession of the point bar will be capped by overbank deposits of Kampar River. Along the Kampar Rivers, there are more than 60% of floodplain sediments and almost all of the floodplain formed by bend migration on the suspended-load channels of Kampar watershed. This formation consist of succession of fine to medium sand and silt/mud, with root traces, that form as drapes on the prograding bank. These beds dip mostly channel wards and quickly wedge out as they grade up and onto the floodplain. The depositional model is presented showing how lateral accretion can make a significant contribution to the preservation of fine-grained within channel deposits in contemporary floodplains. The examples presented here demonstrate that analogues to ancient point-bar deposits containing alternating sandstone and shale sequences are common in the low-energy fluvial environments of Riau rivers especially Kampar rivers.Kampar Rivers, lateral accretion, floodplain, meandering, depositional model
Analysis of Structural Geology based on Sattelite Image and Geological Mapping on Binuang Area, Tapin Region, South Kalimantan
No full textStudy area lies on Binuang, Binuang District, Tapin Regency, South Kalimantan Province. In geographpically this area lies on 115° 6' 28" E - 115° 11' 28° E dan 3° 13' 10" S - 3° 8' 10" S and include in topographic map sheet no. 1712-63 (Binuang) which published by Bakorsurtanal.
This area has a complex conditional of structural geology based on satellite image feature and supported by geological field mapping. There are five major faults and one fold could be identified clearly on this study area, which are Normal Fault (Batangbanyu), Thrust Fault (Gunung Batu-1), Strike-slip fault (Gunungulin, Gunung Batu-1, Bumbun, and Hantan) and Batangkayu syncline. Mechanism of forming faults are affected by Meratus Range movement on east. Starting on paleogen, extensional stress more extensive which resulting Batangbanyu normal fault. Then, at Neogene, compressional stress more extensive working in this area which resulting synthetic fault (Gunungulin and Gunungbatu-2) with NS – SE direction and antithetic fault (Bumbun and Hantan) at opposite direction. Another fault are formed perpendicular with major fault which are Gunung batu-1 thrust fault and Batangkayu syncline
Preliminary Analysis of Slope Stability in Kuok and Surrounding Areas
No full textThe level of slope influenced by the condition of the rocks beneath the surface. On high level of slopes, amount of surface runoff and water transport energy is also enlarged. This caused by greater gravity, in line with the surface tilt from the horizontal plane. In other words, topsoil eroded more and more. When the slope becomes twice as steep, then the amount of erosion per unit area be 2.0 - 2.5 times more. Kuok and surrounding area is the road access between the West Sumatra and Riau which plays an important role economies of both provinces. The purpose of this study is to map the locations that have fairly steep slopes and potential mode of landslides. Based on SRTM data obtained, the roads in Kuok area has a minimum elevation of + 33 m and a maximum + 217.329 m. Rugged road conditions with slope ranging from 24.08 ° to 44.68 ° causing this area having frequent landslides. The result of slope stability analysis in a slope near the Water Power Plant Koto Panjang, indicated that mode of active failure is toppling failure or rock fall and the potential zone of failure is in the center part of the slope.</jats:p
Analysis of Porosity and Permeability on Channel Deposit Sandstone using Pore-gas Injection and Point Counting in Sarilamak Area, West Sumatra
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Geophysical Modelling Using Gravity Data of Meteorite Impact Crater at Bukit Bunuh, Lenggong, Perak, Malaysia
No full textA geophysical survey using gravity method was conducted at Bukit Bunuh, Lenggong,
Perak, Malaysia, to determine the occurrence of a subsurface impact crater, based on the
discovery of meteorite impact rock, suevite, in the study area. A standard correction was
applied to all the gravity data to produce Bouguer gravity anomaly of the study area. The
Bouguer gravity anomaly was used to produce several maps of gravity anomalies by
filtering processes and relate them to the geological structure and tectonic history of the
study area. Data processing and interpretation were conducted using geophysical
software, Oasis Montaj. This software was used in a number of gravity data filtering
processes, such as Low Pass Filter (LPF) and the Total Horizontal Derivative (THD).
Bouguer gravity anomaly map shows a circular structure in Bukit Bunuh area which is
interpreted as a remnant of meteorite impact crater. The gravity anomaly appears to
decrease from the edge of the crater and increases at the center. This feature indicates a
complex crater structure which has central uplift. The Total Horizontal Derivative map of
residual gravity anomaly shows structural trend such as lineaments and faults that
dominant to the northwest‐southeast direction. A model was produced using GM‐SYS 3D
software to determine the geometry of the impact crater. The interpreted 3‐D model
shows a diameter of the impact crater was approximately 2368 m and depth of about 400
m. The model of the crater appears to tilt toward southeast, which illustrates the ancient
meteorite that hit this area about 1.83 million years ago possibility came from northwest
direction
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