https://www.mongoliajol.info/index.php/MGS/issue/feed Mongolian Geoscientist 2019-03-11T00:28:18+00:00 Batkhishig Bayaraa bkhishig@must.edu.mn Open Journal Systems <p>Mongolian Geoscientist&nbsp; published by the <a title="MUST" href="http://www.must.edu.mn/" target="_blank" rel="noopener">Mongolian University of Science and Technology </a>with support from the Mongolian Geological Society.</p> https://www.mongoliajol.info/index.php/MGS/article/view/1060 Preface 2019-02-13T03:18:50+00:00 Batkhishig Bayaraa mongoliangeoscientist@must.edu.mn <p>No abstract in English</p> 2018-12-31T00:00:00+00:00 ##submission.copyrightStatement## https://www.mongoliajol.info/index.php/MGS/article/view/1061 Petrochemical characteristics of late Paleozoic magmatic rocks of the Mandakh area, southeast Mongolia 2019-03-11T00:17:57+00:00 Undarmaa Batsaikhan undarmaa@must.edu.mn Tsuchiya Noriyoshi undarmaa@must.edu.mn Chimedtseren Anaad undarmaa@must.edu.mn Batkhishig Bayaraa undarmaa@must.edu.mn <p>The late Paleozoic magmatic rocks are widely distributed in the Mandakh area which is located in the Gurvansaikhan and Manlai terrains, where porphyry Cu deposits occur. In this paper we discuss petrochemical features and mineral assemblages of magmatic rocks in the Mandakh area. Furthermore, we compared petrochemical characteristics of magmatic rocks in the Mandakh area with host magmatic rocks of the Tampakan deposit (Philippines), Cerro Colorado deposit (Chili) and negative criteria of Cu deposits (Japan) due to try to characterize potential of the porphyry copper deposit related to magmatic rocks in Mandakh area. Geochemical features of magmatic rocks in Mandakh area are calc-alkaline, magnetite-series, I-type and similar to adakite type. The Devonian intrusive rocks comprised of syenite and syenogranite, while the Carboniferous intrusive rocks consist of granodiorite, monzodiorite, quartz-monzonite and hornblende granite. Devonian magmatic rocks are more alkaline in composition. Although, Devonian and Carboniferous magmatic rocks are slightly different from each other. Comparing with bonanza copper deposits in the world, they are possible to host porphyry mineralization.</p> 2018-12-31T00:00:00+00:00 ##submission.copyrightStatement## https://www.mongoliajol.info/index.php/MGS/article/view/1062 New orogenic type gold occurrences in the Uyanga ore knot (Central Mongolia) 2019-03-11T00:21:32+00:00 Ariunbileg Sodov ariunbilegsodov@yahoo.com Olga Gaskova ariunbilegsodov@yahoo.com Altansukh Gankhuyag ariunbilegsodov@yahoo.com Dagva-Ochir Lkhagvasuren ariunbilegsodov@yahoo.com Otgonbaatar Dorjsuren ariunbilegsodov@yahoo.com Oyunchimeg Tumen-Ulzii ariunbilegsodov@yahoo.com Battushig Altanbaatar ariunbilegsodov@yahoo.com <p>The Uyanga ore knot district of the Khangay metallogenic zone are hosted by the lower-middle Devonian volcanogenic-sedimentary Erdenetsogt formation. About 40 samples were collected from the host rocks, veins and quartz veins in the Uyanga ore knot district in 2016. The new Burgetei, Ult and Senjit gold occurrences were studied. The quartz-sulfide, gold-arsenic and gold-antimony-mercury mineralization are determined in the berecitization, silicification, limonitization and glauconization altered metasomatic zones within the Uyanga ore knot districts. The rocks of the Erdenetsogt formation have an irregular gold content: 0.96 g/t Au is determined in quartz vein taken from trench of the Burgetei occurrence (BG-7/16), Au content is highest up to 3.5 g/t in the quartzite-jasper (Ult-7/16 and Ult-9/16) cut by quartz veins in the Ult occurrence. The Senjit occurrence represents Au-Hg-Sb epizonal level of orogenic gold deposits structure with highest Hg content up to 851 ppm. This year no sulfide minerals were found in the siltstone of this occurrence. The Au content of arsenical pyrite of the Burgetei and Ult is below the detection limit by electron microprobe analysis. The Au content of arsenopyrite of the Ult occurrence is highest (up to 238 ppm). Therefore, the ore-mineral assemblages in the gold occurrences reflect the differences between the three explored sites, formed in the course of fluid evolution during the fluid-rock interaction. Variable concentrations of indicative elements (As, Te, Sb, Hg) and their ratios confirm this fact. The geodynamic position, the type of the hydrothermal alteration of both igneous and sedimentary rocks, textures and mineral assemblages, the mineralization sequences are consistent with orogenic classification for the Burgetei, Ult and Senjit gold occurrences.</p> 2018-12-31T00:00:00+00:00 ##submission.copyrightStatement## https://www.mongoliajol.info/index.php/MGS/article/view/1064 Anthropogenic landform evolution remoted by satellite images in Tuul River basin 2019-03-11T00:24:25+00:00 Davaagatan Tuyagerel dtuyagerel@gmail.com Alexander Orkhonselenge rkhnslng@num.edu.mn <p>Industrialization, construction and transportation network are abruptly grown and urban infrastructure is densely expanded due to rapid population growth, i.e., urbanization process is notably intensive in Ulaanbaatar as like as other cities in the world. Human activity in the overpopulated city distinctly modifies landforms and antipathetically impacts on the environment. Channel, floodplain and terraces of Tuul River draining through Ulaanbaatar have been strongly affected by the human activity. Reduction in water resource and water pollution of Tuul River are caused by bio-waste, solid waste and wastewater released from industries, thermal and electric power stations, constructions and companies operating along the river beach. This study presents landform evolution induced by human activity in Tuul River basin. More investigation is needed to infer anthropogenic landform evolution in large river basins in Mongolia based on field works and analytic measurements with further study.</p> 2018-12-31T00:00:00+00:00 ##submission.copyrightStatement## https://www.mongoliajol.info/index.php/MGS/article/view/1065 Hydrogeochemical implications from Ider River in northern Mongolia 2019-03-11T00:26:10+00:00 Alexander Orkhonselenge rkhnslng@num.edu.mn Amgalan-Erdene Nyamjantsan rkhnslng@num.edu.mn <p>This study presents the hydrogeochemical implications resulted from Ider River, one of headwaters of Selenge River in northern Mongolia which is a main headwater of Lake Baikal in southeastern Russia, being included in a drainage basin of the North Arctic Ocean. Surface water and groundwater were collected and estimated with hydrogeochemical analyses of major ionic compositions in order to determine water quality in the catchment of Ider River in northern Mongolia. Result shows that the downstream of Ider River is more polluted than upstream of Ider River and Khunjil River, an inflow of the Ider River. Surface water of Ider River and groundwater in the catchment of the Ider River are comparable with their anions and cations. Ider River is highly enriched with an anion of Cl<sup>-</sup> in 2-3 times, cations of Na<sup>+</sup>+K<sup>+</sup> in 2-3 times and NH<sub>4</sub><sup>+</sup> in 0.5-1.0 times than those in groundwater in the catchment of Ider River. The hydrogeochemical results show that the surface water of Ider River is mainly polluted by solid wastes along its valley. More investigations with detail geochemical analyses are needed from the large rivers comprising surface water resource in Mongolia to review the hydrological evolution in Mongolia and Central Asia in the late Holocene.</p> 2018-12-31T00:00:00+00:00 ##submission.copyrightStatement## https://www.mongoliajol.info/index.php/MGS/article/view/1063 Drone brings new advance of geological mapping in Mongolia: Opportunities and challenges 2019-03-11T00:28:18+00:00 Otgonbayar Dandar Otogo@geokankyo.tohoku.ac.jp Atsushi Okamoto Otogo@geokankyo.tohoku.ac.jp Masaoki Uno Otogo@geokankyo.tohoku.ac.jp Undarmaa Batsaikhan Otogo@geokankyo.tohoku.ac.jp Burenjargal Ulziiburen Otogo@geokankyo.tohoku.ac.jp Noriyoshi Tsuchiya Otogo@geokankyo.tohoku.ac.jp <p>Unmanned aerial vehicles (UAVs) or drones have revolutionized scientific research in multiple fields. Drones provide us multiple advantages over conventional geological mapping or high-altitude remote sensing methods, in which they allow us to acquire data more rapidly of inaccessible or risky outcrops, and can connect the spatial scale gap in mapping between manual field techniques and airborne, high-altitude remote sensing methods. Despite the decreased cost and technological developments of platforms, sensors and software, the use of drones for geological mapping in Mongolia has not yet been utilized. In this study, we present using of drone in two areas: the Chandman area in which eclogite is exposed and the Naran massif of the Khantaishir ophiolite in the Altai area. Drone yields images with high resolution that is reliable to use and reveals that it is possible to make better formulation of geological mapping. Our suggestion is that (1) Mongolian geoscientists are encouraged to add drones to their geologic toolboxes and (2) drone could open new advance of geological mapping in Mongolia in which geological map will be created in more effective and more detailed way combined with conventional geological survey on ground.</p> 2018-12-31T00:00:00+00:00 ##submission.copyrightStatement##