Bulletin of the Mineral Research and Exploration (BMRE)
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ARCHAEOLOGICAL AND GEOLOGICAL CONCEPTS ON THE TOPIC OF ANCIENT MINING
No full textGeological and archaeological research on ancient mining and metallurgy are actually targeting the same goals: understanding the nature and value of a mining operation. Geologists are intent on locating and qualifying ores and minerals for future use, whereas archaeologists strive to link ores to relevant historic and prehistoric metal artifacts and activities. This article discusses research into ancient Anatolian metallurgy by underscoring the overlap between geological and archeological practices. The work of archaeologists and geologists can be mutually beneficial through a close collaboration on the collection and analysis of field data. Their accumulated and combined knowledge would accelerate the progress towards placing ancient mining activities in a chronological and meaningful context
REVIEW OF THE OCCURRENCE OF TWO NEW MINERALS IN THE EMET BORATE DEPOSIT, TURKEY: EMETITE, CA7NA3K(SO4)9, AND FONTARNAUITE, NA2SR(SO4)[B5O8(OH)](H2O)2
No full textGEOLOGICAL FACTORS CONTROLLING POTENTIAL OF LIGNITE BEDS WITHIN THE DANIŞMEN FORMATION IN THE THRACE BASIN
No full textThis project has been conducted for the General Directorate of Turkish Coal Enterprise. The aim of this study is to understand lignite potential of the basin. Subsurface data ( including numerous wells and several seismic lines) provided by TPAO, MTA and TKİ were used. Structure and thickness maps of Oligocene-Miocene-Pliocene units prepared for the basin. Purpose of this work is to understand economical values of lignite seam beds interbedding in the Danişmen Formation (Oligocene-Early Miocene). For this purpose, from bottom to top following maps were prepared: Structural map of the top Osmancık (Oligocene) Formation, thickness map of the Danişmen Formation, paleo-topographic map of unconformity surface which is at the top of the Danişmen Formation, total thickness map of Ergene-Kırcasalih formations (Late Miocene-Pliocene). Finally total thickness map of the lignite layers was prepared. It was the main purpose of the work. Lignite seam layers are located in middle of the Danişmen Formation. Also several stratigraphic correlations were conducted to understand lateral continuation of lignite layers. The first obstacle to reach lignite is thickness of the Ergene and Kırcasalih formations which overlie lignite bearing Danişmen Formation. Main structural event controlling the thickness variation of the Danişmen Formation is Thrace Fault System (Perinçek, 1991); it was active during Middle Miocene. Danişmen Formation extensively or partially was eroded along the fault zone and on the en-echelon folds of the fault system. Amount of erosion is variable and in some areas Danişmen Formation completely was eroded. As a result Ergene Formation lies directly on Osmancık Formation. Lignite layers are also eroded at these localities. Elevated areas related the Thrace Fault System partially was eroded; however these areas were still paleo-elevated areas during the accumulation of Ergene Formation. Onlapping sequence of Ergene Formation is thinner on these areas. At the end of this project, thicker lignite areas were delineated. Addition to this, thin overburden areas on lignite are located. Considering these result, new permit areas were selected.. In order to refine this work, a suggested facies map of Danişmen Formation is advise to be prepared
DIFFERENTIATION PROCESSES İN LATE CRETACEOUS ULTRAPOTASSIC VOLCANICS AROUND AMASYA
No full textLate Cretaceous lithologies around Amasya region are represented by Pontide fore-arc basin units which corresponds a volcanoclastic sequence. This sequence has the products of alkaline ultrapotassic magmatism accompanying calcalkaline lavas which are abundant along Pontide arc. The ultrapotassic rocks which are classified as leucitite, minette and trachyte based on their mineralogical composition, occur as dikes, stocks and rarely lava flows as to be comprised by the Late Cretaceous Volcanoclastic Succession (LCVS). Fractional crytallization accompanied by assimilation (AFC) is a low pressure processes able to differentiate ultrapotassic parental melts to various compositions in a continental margin tectonic setting.The trachytes are the youngest and the most evolved members of LCVS. Therefore we performed AFC modelling using the most primitive minette sample as starting composition and calculated the fractionation trends based on the theoretical mineralogical compositions. We also used the Triassic metapelitic basement rocks of Central Pontides as assimilant. The AFC modelling results imply that it is possible to produce trachytes by adding Central Pontide basement rocks up to 5 %, begining from the most primitive phonolitic sample of Amasya. However the differentiation of leucitites and minettes is able to be explained by neither fractional nor assimilation processes
GEOLOGICAL FEATURES OF NEOGENE BASINS HOSTING BORATE DEPOSITS: AN OVERVIEW OF DEPOSITS AND FUTURE FORECAST, TURKEY
No full textThe geometry, stratigraphy, tectonics and volcanic components of the borate bearing Neogene basins in western Anatolia offer some important insights into on the relationship between basin evolution, borate formation and mode of extension in western Anatolia. Some of the borate deposits in NE-SW trending basins developed along the ‹zmir-Bal›kesir Transfer Zone (‹BTZ) (e.g. Bigadiç, Sultançay›r and Kestelek basins), and other deposits in the NE-SW trending basins which occur on the northern side of the Menderes Core Complex (MCC) are The Selendi and Emet basins. The K›rka borate deposit occurs further to the east and is located in a completely different geological setting and volcanostratigraphic succession. Boron is widely distributed; including in soil and water, plants and animals. The element boron does not exist freely by itself in nature, but rather it occurs in combination with oxygen and other elements in salts, commonly known as borates. Approximately 280 boron-bearing minerals have been identified, the most common being sodium, calcium and magnesium salts. Four main continental metallogenic borate provinces are recognized at a global scale. They are located in Anatolia (Turkey), California (USA), Central Andes (South America) and Tibet (Central Asia). The origin of borate deposits is related to Cenozoic volcanism, thermal spring activity, closed basins and arid climate. Borax is the major commercial source of boron, with major supplies coming from Turkey, USA and Argentina. Colemanite is the main calcium borate and large scale production is restricted to Turkey. Datolite and szaibelyite are confined to Russia and Chinese sources. Four Main borax (tincal) deposits are present in Anatolia (K›rka), California (Boron), and two in the Andes (Tincalayu and Loma Blanca). K›rka, Boron and Loma Blanca have similarities with regard to their chemical and mineralogical composition of the borate minerals. Colemanite deposits with/without probertite and hydroboracite are present in west Anatolia, Death Valley, California, and Sijes (Argentina). Quaternary borates are present in salars (Andes) and playalakes and salt pans (USA-Tibet). Boron is a rare element in the Earth’s crust, but extraordinary concentrations can be found in limited places. The formation of borate deposits can be classified as follows: a skarn group associated with intrusives and consisting of silicates and iron oxides; a magnesium oxide group hosted by marine evaporitic sediments; and a sodium– and calcium–borate hydrates group associated with playa-lake sediments and explosive volcanic activity. Some conditions are essential for the formation of economically viable borate deposits in playa-lake volcano-sedimentary sequences: formation of playa-lake environment; concentration of boron in the playa lake, sourced from andesitic to rhyolitic volcanics, direct ash fall into the basin, or hydrothermal solutions along graben faults; thermal springs near the area of volcanism; arid to semi-arid climatic conditions; and lake water with a pH of between 8.5 and 11. A borate is defined as any compound that contains or supplies boric oxide (B2O3). A large number of minerals contain boric oxide, but the three that are most important from a worldwide commercial standpoint are borax, ulexite, and colemanite, which are produced in a limited number of countries. Turkey has the largest borax, ulexite and colemanite reserves in the world and all the world’s countries are dependent upon the colemanite and ulexite reserves of Turkey. Most of the world’s commercial borate deposits are mined by open pit methods. Brines from Searles Lake, and presumably the Chinese sources, are recovered by either controlled evaporation or carbonation. Boric acid is one of the final products produced from most of the processes. Further research on the mineralogy and chemistry of borate minerals and associated minerals will the production and utilization of borate end-products. Many modern industries need industrial borate minerals, and many people use their products. In addition, boron is essential to plant life, and by extension, all life so it’s hard to imagine our world without using it. Therefore, borates and their products are critical to the Sustainable Development of the world
LATE PLEISTOCENE GLACIATIONS AND PALEOCLIMATE OF TURKEY
No full textGlaciers respond quickly to climatic changes and thus they are considered to be very accurate indicators of changes in atmospheric conditions. Similarly, the extent of past glaciers gives valuable insights into paleoclimatic changes. For this purpose, we reviewed the paleo-glaciated mountains where cosmogenic surface exposure dating was applied inTurkey. We also evaluated the paleoclimatic results obtained from these studies to provide a regional overview. Twenty-seven mountains in Turkey are high enough to support Quaternary valley glaciers or ice caps. The timing of glaciations was reported mainly by cosmogenic dating of moraines. We re-evaluated the dated sites and recalculated some of the published cosmogenic ages using the up-to-date production rates. The oldest geochronological records reported from the region belong to the glaciations before the globally defined Last Glacial Maximum (LGM). These glaciers developed probably during the beginning of the last glaciation (MIS 4; 71 ka ago) and stopped advancing at the end of the MIS 3 (at 29-35 ka ago). Later, glaciers expanded and reached to their most extensive locations during MIS 2 (after 29 ka ago). They reached maximum extents between 21.5 ka ago and 18.5 ka ago. This local-LGM was synchronous with the globalLGM. After the LGM, the glaciers started to retreat to less extensive positions and deposited their moraines ~16 ka ago during the Late Glacial. The Younger Dryas (~12 ka ago) advances were also reported from a limited number of mountains. Rare Early Holocene glaciations were dated to 8.5 ka in the interior regions. Late Holocene (1-4 ka ago) and Little Ice Age (between 1300-1850 AD) advances were also observed. We reconstructed the paleoclimate using glacier modeling together with paleoclimate proxy data from several regions. The results show that LGM climate was 8-11°C colder than today and moisture levels were 1.5 to 2 times in SW Turkey, somewhat similar to modern values in central parts and 30 % drier in the NE. The Late Glacial was colder by 4.5-6.4°C based on up to 50 % wetter conditions. The Early Holocene was 2.1-4.9°C colder and up to twice as wet as today, while the Late Holocene was 2.4-3°C colder and its precipitation amounts approached to similar conditions as today
THE GEOLOGY OF GÖKÇEADA (ÇANAKKALE)
No full textThe geology and especially the magmatic rocks of Gökçeada, which is the biggest island of Turkey and located at 20 km’s west of Biga Peninsula, constitute the subject of this study. Late Ediacaran/ Early Paleozoic aged Çamlıca metamorphics which crop out with a tectonic uplift in a narrow area in northwest of Gökçeada are the oldest rocks of the island. Early Eocene aged Karaağaç Formation which is formed by submarine fan deposits unconformably overlies Çamlıca metamorphics. As for the Dağiçitepe volcanic member which is formed by rhyolitic lavas, tuff and tuffites emplaced into Karaağaç Formation cutting Çamlıca metamorphics is the oldest volcanic unit of the study area. On Karaağaç Formation, Koyunbaba Formation has unconformably been deposited which consists of Middle Eocene shallow marine sediments. Then it has conformably been overlain by Soğucak Formation which consists of SE-NW extending reefal limestone. Middle-Upper Eocene aged Ceylan Formation which conformably overlies the Soğucak Formation and the early Oligocene aged Mezardere Formation which conformably overlies Ceylan Formation have been deposited due to turbiditic currents in deep marine environment. Late Eocene(?) – Oligocene aged subvolcanics which cut Mesozoic and Eocene units and emplaced into Eocene aged sedimentary units in the form of crypto dome and dome form the recent rigid topography of the study area and are the second magmatic phase called the “Gökçeada Domes”. Diorite-monzonites porphyry which crystallized in lower zones of subvolcanics on the other hand constitutes Mutludere intrusion. In eastern and southern parts of Gökçeada, Late Oligocene Gökçeada ignimbrites are located which are observed in the form of pumice flows on Mezardere Formation. These ignimbrites are then overlain by Early Miocene aged Kesmekaya volcanics which are formed by blocky ash flows. Middle Miocene aged Eşelek volcanics consisting of lava and pyroclastics with composition basaltic andesite and andesite are observed on a large area in east of Gökçeada. Upper Miocene aged Çanakkale Formation which is generally formed by the intercalation of poor consolidated conglomerate, sandstone, siltstone and marl crops out in narrow regions at east, southeast and south of Gökçeada. Quaternary alluvial deposits and debris composed of loose, unconsolidated sand, silt and other sediments unconformably overlie all previous units and complete the succession. Main tectonic structures of Gökçeada are formed by right lateral oblique faults which developed in Neo-tectonic period. Anahta
INVESTIGATION OF IRRIGATION WATER QUALITY OF SURFACE AND GROUNDWATER IN THE KÜTAHYA PLAIN, TURKEY
No full textThe Kütahya plain is one of the plains in Kütahya/Turkey, where drinking, agricultural and industrial water supplies are highly dependent on groundwater resources. The local population largely depends on water from alluvial shallow aquifer waters and some on the Felent and Porsuk rivers. Appraisal of surface and groundwater quality is extremely important to make sure the sustainable use of it for drinking, agricultural, and industrial purposes. The chemical quality of surface and groundwater of Kütahya plain has been studied in detail in order to have better understanding of potential water quality. A total of 21 groundwater samples and 6 surface water samples were collected in and around the plain. The relative abundance of major ions (meq/l) for most of the water samples were Ca2+ \u3eMg2+ \u3e(Na++K+) for cations and HCO3- \u3eSO42- \u3eCl- for anions. Five hydrochemical facies have been identified based on the major ion chemistry of the surface and groundwater of this area. However, based on hydrochemical facies, the type of water that predominates in the study area is Ca-Mg/Mg-Ca-HCO3 type in both December 2013 and June 2014. There is no significant change in the hydrochemical facies noticed during the two sampling periods. The chemical Index such as Sodium Absorption Ratio (SAR), Residual Sodium Carbonate (RSC), Sodium Percentage (%Na), Permeability Index (PI), Kelley Index (KI), Magnesium Ratio (MR), Potential Salinity (PS) and Total Hardness (TH) were calculated. The results indicated that SAR, RSC and KI values revealed 100%, %Na value revealed 92.6%, PI and PS values revealed 85.2% and MR value revealed 66.7% of water samples are within the safe limit suitable for irrigation. To sum up, the quality of surface and groundwater of Kütahya plain in general was suitable for irrigation
LATE PERMIAN UNCONFORMITY AROUND ANKARA AND NEW AGE DATA ON THE BASEMENT ROCKS, ANKARA, TURKEY
No full textAt southwest of Gölbafl› (Ankara) there are two different sequences in tectonic contact. The one at the bottom with low-degree metamorphism is represented by phyllite, metabasite, crystallized limestone, schist and quartz porphyry veins. Above them are early Carboniferous-late Permian neritic and pelagic carbonates which are unconformably overlain by late Permian clastics and carbonates. Samples collected from neritic carbonates yielded early Carboniferous (Visian-Serpuhovian) to middle Carboniferous (Bashkirian- Moskovian) ages. These carbonates of shallow facies character are overlain by radiolarite-bearing pelagic deposits of middle Carboniferous-Permian age. Fossils from the upper most neritic carbonates gave Kubergandian-Murgabian age. This PermoCarboniferous sequence is unconformably overlain by a sequence consisting of clastics and carbonates. Basal conglomerates and sandstones contain abundant quartz and fewer amounts of carbonated-cemented metamorphic rock fragments and they change to medium-thick bedded dolomitic limestone and limestones to the top. The age of these carbonates of shallow marine character is found Murgabian-Dorashamian. It is suggested that late Paleozoic carbonate basement was deposited in a neritic environment during early-middle Carboniferous, in a pelagic environment during middle CarboniferousPermian and again in a neritic environment during Kubergandian-Murgabian. Following a deformation stage, it was accreted onto the Variscan basement at north and carbonate deposition took place as a result of late Permian transgression and finally some of exotic blocks within the upper Karakaya Complex were derived from this basement
VERTICAL AND HORIZANTAL ANALYSIS OF CRUSTAL STRUCTURE IN EASTERN ANATOLIA REGION
No full textThe tectonic regime of Eastern Anatolia is determined by Arabian-Eurasian continentcontinent convergence and the mechanism occurred with the convergence. North Anatolian Fault Zone (NAFZ), Eastern Anatolian Fault Zone (EAFZ), North Eastern Anatolian Faults and Bitlis Zagros Suture Zone are formed by this convergence, represent the characteristic of lithospheric structure of the region. In the scope of this study, the gravity anomalies of Eastern Anatolia were used for investigating the lithospheric structure. Firstly, second order trend analyses were applied to gravity data for examining the characteristic of the anomaly. Later, the vertical and horizontal derivatives methods were applied to the same data. Generally, the purpose of the applying derivative methods is determining the vertical and horizontal borders of the structure. Therefore, this method gives the opinion about the characteristic of the lithospheric structure of the study region. According to the results of derivative methods, the structure transitions were increased rather especially with Bitlis Zagros Suture Zone. At the last step, the gravity studies were evaluated together with the seismic activity of the region. Consequently, the geodynamical structure of the region is examined with the previous studies done in the region