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Abstract

Optically stimulated luminescence (OSL) dating of fine-grained (4–11 μm) fluvial sediments is rarely attempted but is crucial for constraining the evolution of mud-dominated floodplains. This study investigated the applicability of OSL dating to fine-grained deposits in the Mekong River, Cambodia based on a very young (<600 yr) point-bar to riverbank succession and modern flood deposits. In succession, fine-grained quartz OSL provided the youngest ages, whereas age estimates by multi-grain sand-sized quartz OSL, and feldspar and polymineral infrared-stimulated luminescence are >200 years older than the fine-grained quartz OSL age estimates. Ages of fine-grained quartz OSL are concordant with the minimum ages obtained from the single-grain quartz OSL. These results are supported by the generally small residual doses (<0.1 Gy) measured in modern fine-grained floodplain deposits. This indicates that fine-grained sediments in the Mekong River (Cambodia) are sufficiently bleached at deposition and can yield reliable quartz OSL ages for establishing the chronology of the floodplain. The sufficient bleaching of fine-grained quartz partly results from the long transport distance and may also occur in other large river systems.

Abstract

Energy crises is the one of the major problem that was faced by Pakistan in order to overcome on that crises Pakistan need to be developed and improvement in energy sector, Throughout in the country the demand of water and power increasing day by day therefore hydropower project are the need of the hour in Pakistan. Before initiation of any project EIA play important role in evaluating the nature of the project on different factors. Government of Pakistan planned one of the mega hydropower project diamer basha dam was planned in Gilgit Baltistan. It was intended to conduct the research work on describing significant factors so as to evaluate the influence of the project on them and develop guidelines for environmental assessment for these factors. To find out these significant factors the methodology was adapted to conducting field investigation. Besides to assess the relevant impact questionnaires were developed. Finally, in order to reduce the negative impact of the project on the predefine factor mitigation measure was suggested. It is anticipated that this study work support in developing structure work to be executed as mitigation measures and boost the advantages of the project.

Abstract

This study presents the estimated remaining quantity of overburden material (topsoil, completely to highly weathered rock) and remaining geological reserve at Sibanyis Quarry, Kuching after the quarry has been operated for years. Desktop study including literature search was carried out prior field investigation. Three boreholes together with latest topographical and detail survey was conducted to obtain the latest data at Sibanyis Quarry, Kuching. Based on this Geological Reconciliation Study, the estimated total remaining geological rock reserve is 40,022,767 metric tons, and the weathered rock and top soil are 2,159,688 BCM and 1,247,697 BCM respectively. The assumptions that are taken into consideration are top soil thickness of 11m, weathered rock thickness of 15m and rock density of 2.64 mt/m3.

Abstract

Integrated well dataset and seismics delineated the PGS field onshore Niger Delta for reservoir identification. Gamma ray, resistivity, Neutron and density Logs identified four lithologies: sandstone, shaly sandstone, shaly sand and shale. They consist of sand-shale intercalation with the traces of shale sometimes found within the sand Formation. Petrophysical parameters of the reservoirs showed varying degree of lower density, low gamma ray, high porosity and resistivity response with prolific hydrocarbon reservoir G due to its shale volume and the clean sand mapped as a probable hydrocarbon reservoir. 3D seismic data located both seismic scale and sub-seismic scale structural and stratigraphic elements. Risk reduction in dry hole drilling due fault missing in conventional seismic attribute analysis and interpretation, have to be integrated into the Oil companies standard practice.

Abstract

The Gwal mélange is mapped on a large scale and is divided into the lithological units such as ultramafic, mafic, volcanic, volcanoclastic rocks, pelagic sediments and ophicarbonates. Petrographically, the mapped rocks are classified as harzburgite, dunite, wehrlite, serpentinite, gabbro, basalt, and andesite. These rocks are quite deformed and altered into the secondary minerals. Harzburgite is a layered mantle peridotite consists of olivine and orthopyroxene while dunite lacks the presence of any pyroxene. Serpentinite is the secondary product after peridotite is the product of post magmatic stages. The mesh structure is usually observed when olivine is completely altered to serpentine. The volcanic rocks are structurally sheeted and pillow type while the volcanoclastic rocks are essentially hyaloclastites associated with pelagic sediments. The Ophicarbonate is composed of serpentinite fragments and carbonate minerals, most probably calcite. Minor to trace amounts of opaque minerals are also present in association with major components. The gabbros may be a fragment of the main crustal rocks and have been formed in a magma chamber by fraction crystallization. The origin of ophicarbonate may be due to gas seeps originated by mantle or as the surficial process where ultramafic rocks and carbonates are mixed through processes of gravity, tectonic crushing and sedimentary reworking. The Gwal mélange may the southern extension of Bagh Complex found beneath the Muslim Bagh Ophiolite. The mantle peridotite of the mélange is much like that of the Khanozai peridotite and may represent its detached blocks. Volcanic and volcanoclastic rocks may be the representatives of the uppermost part of ophiolite crust which might have trimmed off from subducting slab and are, now, part of the Gwal accretionary wedge. The mélange may have tectonically emplacement over the Indian platform sediments along with overlying the ophiolite sheet during the Late Cretaceous.

Abstract

The predominant culture of Sabah consists of a motley of cultures, each of which has been brought in by the different ethnic groups from their indigenous cultures. The total population of Sabah consists of more than thirty different ethnicities and races, and the number of languages and dialects go over eighty. Hence the cultural tourism in Sabah would have varied criteria that can be looked into. The aim of this paper is to use the scoring model in operational research to rank these decision criteria according to highest scores. The preferability of tourist visiting these hot spots is done by ranking their preferability based on a weightage. Highly scored attraction factors would attract more tourists to visit cultural spots in Kota Kinabalu. Therefore, these would help operational managers in the tourism industry to focus on promoting and marketing this sector.

Abstract

Water is indispensable for human life and without water, life cannot exist on earth. Every person required 33 to 35-gallon water per day for drinking and demotic purpose. But due to lack of quality, inefficient water supply designs, intermixing of sewage water and unlined sewage water system, quality of water is deteriorated specially in recent decades and affecting a number of people. In present study, it was inevitable to design a water supply system for selected area to provide safe water supply design for a small community. For this purpose, a study area was selected named as chak.no. 253 RB, Samundri Road Faisalabad. The existing water supply system of the village was built 30 years ago with the problems of leaky pipes, mixing of sewerage water with drinking water was causing water-borne diseases like Diarrhea, Cholera, Giardiasis, Typhoid fever, Schistosomiasis. A computer software abbreviated as EPANET (Environment protection agency network) was used to design a water supply system of the area providing input parameters to the software. For this a profiling survey was conducted to determine the length of pipes and the elevation of each junction. The other input parameters such as the diameter of pipes, pipe network map, head losses were provided. Conclusively, EPANET gave a detailed water supply system plan for specific design period. By adopting this design provided by detailed surveys of the area and EPANET will help to control intermixing of sewage water which ultimately improves the quality of water. The new design is based on technology by using modern techniques (Software). It will provide save and continue supply of water to community. It will also reduce the cost of water billing, leakage, decrease the diseases rate and improve the life standard of people’s lives in that area.

Abstract

The loess sediments widely distributed in the Central Shandong Mountains are sensitive records of East Asian monsoon changes for situating in a key region connected to the Eurasian Plate and the Pacific Ocean. However, the detailed processes of palaeoclimatic changes are poorly understood for the lack of high-resolution chronology. In this study, the chronology of Heishan loess palaeosol sequence in the Central Shandong Mountains is investigated using quartz SAR OSL and K-feldspar post-IR infrared (IR) stimulated luminescence (post-IR IRSL) dating method. The quartz is sensitive, fast component dominated and saturate at ~150 Gy (~50 ka). The measured K-feldspar pIRIR290 De showed no dependency on the first IR stimulation temperature between 50°C and 260°C. The K-feldspar pIRIR290 ages are consistent with the stratigraphy up to ~75 ka. In establishing the chronological sequence for the study section, quartz OSL ages <50 ka and the K-feldspar pIRIR290 ages >50 ka were selected. Derived sedimentation rates show two relatively rapid stages of ~32.0 ± 5.5 cm/ka for the palaeosol (~11–8 ka) and ~54.8 ± 1.1 cm/ka for the loess (~34–30 ka). An erosional hiatus of loess between ~30 ka and ~17 ka is identified. We conclude that the pIRIR290 of loess sediments is applicable for samples during ~8–75 ka.

Abstract

The author of this paper sets out to identify and date the individual editions of Atlas selectus that were published in Leipzig by Johann George Schreiber and his heirs. The paper is based on the analysis of maps and printed registers from 27 unique editions of the atlas. After a brief summary of Schreiber’s non--cartographic activity, the atlas is presented and dating of its eight editions is proposed, from 1741 to the end of the 18th century. Some special editions of the atlas are also identified and briefly described. The estimated production rate of maps in Schreiber’s workshop is compared with earlier research. Finally, a few misconceptions concerning Schreiber and his cartography are clarified.

Abstract

Violet stimulation is a new development in optical dating which has been suggested to extend the upper age limit of optically simulated luminescence (OSL) dating of quartz. Despite the reported advantage, few validation tests and applications have been published so far. The present study investigated the violet stimulated luminescence (VSL) using a single aliquot regenerative dose (SAR) protocol and a multiple aliquot additive dose (MAAD) protocol. Sedimentary quartz samples from four archaeological sites in Europe with independent age controls spanning 40–900 ka were used, including Grotte Mandrin (France), Brooksby Quarry (UK), Cueva Negra del Estrecho del Río Quípar (Spain) and Sima de las Palomas del Cabezo Gordo (Spain). The equivalent dose of a relatively young sample (~40 ka) was successfully determined. However, significant underestimations were observed for older samples with higher doses. These findings indicate the need for further development of the measurement protocol to date high-dose natural samples.