Bulletin of the Mineral Research and Exploration (BMRE)
Not a member yet
1932 research outputs found
Sort by
Paleoenvironmental features and ostracod investigation of Paleogene-Neogene sequences in Babaeski- Lüleburgaz- Muratlı-Çorlu region (Southeastern Thrace, Turkey)
No full textAim of the study is to evaluate the Paleogene-Neogene sequences of Babaeski- Lüleburgaz- Muratlı-Çorlu (Southeastern Thrace, Turkey) region using the micropaleontological analysis on two borehole samples collected by Mineral Research and Exploration (MTA), measured sections and point samples taken from the neighborhood of Silivri, Türkmenli-Çorlu, Babaeski-Lüleburgaz, Edirne –Babaeski regions and Tekirdağ-Hayrabolu road. There the lignite sandstone, siltstone (Early Oligocene aged Danişmen Formation) and silts (Late Miocene-Pliocene aged Ergene Formation) with well-preserved ostracod fauna obtained from the the upper levels of the sequence along with some micro-Mollusca at some levels. The study results showed that lacustrine and lagoonal ostracods including marine species were generally found in the claystone, siltstone and marl of the lower and upper levels of lignite cuts in borehole. The ostracod assemblages identified in the study were compared with other ostracod studies in the Thrace Basin and other parts of Turkey as well as in the Oligocene in Paris, the Akiten Basin, Belgium. In the Early Oligocene sediments, the presence of the Tethys effect was observed in the investigated area. In addition, the ostracod species defined in the Late Miocene-Pliocene are compared with other ostracod studies carried out in the Thrace Basin and other parts of Turkey as well as in the Western and Eastern Carpathians, Caspian Basin and Baltic Sea. According to obtained fauna, the Paratethys effect was determined more than in Tethys in Late Miocene-Pliocene in the studied region.
https://doi.org/10.19111/bulletinofmre.50280
Tectonostratigraphic characteristics of the area between Çayeli (Rize) and İspir (Erzurum)
No full textThe study area is located in the Eastern Pontides between Rize, Çayeli, Arhavi, İspir and İkizdere. In this area, Maçka Tectonic Slice (MTS) and Taşköprü Tectonic Slice (TTS) are exposed. MTS is composed from old to young; Late Jurassic-Early Cretaceous limestone (Berdiga fm.); Turonian- Santonian conglomerate, sandstone, micritic limestone, siltstone, marl, basaltic, basaltic-andesitic lava, pyroclastites (Çatak fm.); Santonian rhyolitic, dacitic lava, pyroclastites, sandstone, clayey limestone (Kızılkaya fm.); late Santonian-Campanian basaltic, andesitic lava, pyroclastites, sandstone, clayey limestone (Caglayan fm.); Campanian-Mastrihtian rhyolitic, dacitic lava, pyroclastites, sandstone, clayey limestone (Çayırbağ fm.);late Maastrichtian-Danian sandstone, claystone, tuff, marl, clayey limestone (Cankurtaran fm.). Sedimentary, volcanosedimentary units in the Late Paleocene-Quaternary range (Erenler, Kaplıca, Melyat, Pazar, Hamidiye formations, and Handüzü, Çağırankaya volcanites) unconformably overlies the MTS. In the study area, Turonian- Maastrichtian basaltic andesitic lavaş, pyroclastites and sandstone, micritic limestone, claystone units (Yağmurdere fm.) belonging to TTS are observed, and Early-Middle Eocene sedimentary and volcanosedimentary units (Yedigöze, Çoruh formations) unconformably overlies the TTS. According to Ar/Ar dating, Çayırbağ formation was determined as 83.2±1.0 Ma, Melyat formation as 47.8±1.6 Ma, and Handüzü volcanics as 4.25±0.55 Ma for andesite level and as 3.93±0.46 Ma for dacite level. The MTS was intruded by Cretaceous-Paleocene Kaçkar granitoid I, Eocene Kaçkar granitoid II, Late Eocene Ardeşen gabbro, while the TTS was intruded by Cretaceous-Paleocene Kaçkar granitoid-I, Late Eocene Güllübağ monzonite.
https://doi.org/10.19111/bulletinofmre.46531
Selandian benthic foraminiferal assemblages of the southwestern Burdur (South of Lake Yarışlı, Western Turkey) and some taxonomic revisions
No full textIn this study, new genera and species are described. These three new genera are Neosistanites (type species Sistanites iranica), Parahaymanella (type species Parahaymanella hakyemezae) and Pseudohottingerina (type species Pseudohottingerina burdurensis). Neosistanites new species and new genus (N. sozerii, N. okuyucui, N. guvenci, N. dageri, N. catali, N. armagani, N. inali) and Neosistanites iranicus are defined. Parahaymanella is the new genus and its new species (P. hakyemezae, P. bozkurti and P. alanae). New species of new genus Pseudohottingerina (Ps. burdurensis and Ps. yarisliensis). Laffitteina anatoliensis, Laffitteina thraciaensis, Sirtina paleocenica, Ankaraella minima new species and Laffitteina erki, Laffitteina mengaudi, Ankaraella trochoidea species are defined and illustrated. Known Akbarina primitiva, Bolkarina aksarayi, Biloculinites cf. paleocenica, Miscellanea? globularis, Globoflarina? sphaeroidea species and Heterillina sp., Keramosphaera sp., Textularia sp., Chrysalidina? sp., Kolchidina? sp., Lockhartia? sp., Popovia? sp. and Thalmannita? sp., genera, illustrated only. Only photographs of undescribed benthic foraminifera genera (miliolid, miscellanid, planulinid, rotaliid, mississippinid, aglutine) are given. The definition of a new family (Neosistanitidae), the classification of the Neosistanites, the type species and species transfers between the genera, the emendation of the Ankaraella genus and the corrections of the Ankaraella trochoidea were made. Photographs of some fossil algae are given in plates. All material (SBZ 2) belongs to the Selandian. https://doi.org/10.19111/bulletinofmre.49462
A new species of Nummulites Lamarck (Nummulitidae, Foraminiferida) from Central Turkey
No full textA new nummulitid species Nummulites sireli n. sp. is described from the middle Lutetian of the Çayraz section, North of Haymana, South of Ankara, Turkey. The new species is referred in to the N. distans group, of which six other species from the Haymana and Çiçekdağ regions of Central Anatolia are identifi ed.
https://doi.org/10.19111/bulletinofmre.41370
Geochemical characteristics of Sabalan volcanic rocks in Northwestern Iran
No full textSabalan is a voluminous stratovolcano situated in the northwestern part of Alborz-Azerbaijan zone, 25km from Meshkinshahr. It is separated by tectonic faults from Sarab plain and Meshkinshahr. The composition of Sabalan volcanic rocks ranges from andesite, trachyandesite to dacite. The rocks have hypocrystalline porphyritic texture with a glassy matrix and microlite . Plagioclase, amphibole, pyroxene, biotite, and oxides are the main phenocryst phase of the rocks. Some plagioclases show disequilibrium textures (sieve texture and oscillatory zoning). The sieve texture and oscillatory zoning in the plagioclases may be indicative of magma mixing processes in the genesis of the Sabalan volcanic rocks. Geochemical data reveal that the Sabalan lavas exhibit calk-alkaline major-oxide trends with a sodic character and they range in composition from andesite to dacite. Pre-caldera and post-caldera volcanic rocks have similar geochemical features with enrichments in LILE and LREE relative to HFSE and HREE, respectively, and have negative Ti, Nb, and Ta anomalies. Ba/Ta ratios higher than 450 and La/Nb ratios ranging between 2 and 3 indicate a volcanic arc setting for the studied rocks. Based on field and geochemical studies, Sabalan is a subduction-related volcano, occurred as a result of subduction of Neo-Tethyan oceanic crust beneath the Iranian microplate.
https://doi.org/10.19111/bulletinofmre.45156
Investigation of feldspar raw material potential of alkali feldspar granites and alkali feldspar syenites within Central Anatolia
No full textAlkali feldspar granites are intrusive rocks and mainly composed of alkali feldspar, quartz and plagioclase. They represent one of the major sources that provide raw materials for glass and ceramics industry because of their high feldspar and quartz contents. In addition to alkali feldspar granites, also alkali feldspar syenites have potential to become raw material source due to their high feldspar and feldspathoid contents. These rocks are exposed in large areas within Central Anatolia. For this reason, alkali feldspar granites within Ağaçören Intrusive Suite (AIS) (Kalebalta, Yıldırımlı, Çerkezuşağı, Çatalçeşme, İbrahimbeyli, Deliler, Ekecik, Sipahiler, Camili, Yaylak, Namlıkışla), Hacılı Suite (Sarıhacılı), Cefalık, Behrekdağ, Terlemez and alkali feldspar syenites within Bayındır, Hamit and İdişdağı Suites are investigated. This study aims at investigating possible potential of alkali feldspar (orthoclase, microcline), plagioclase (albite, oligoclase) and quartz minerals within these rocks in glass and ceramic industry as raw materials. Additionally, studied samples are compared with different granites around the world. Alkaline element and iron contents of the studied rocks have high and relatively high Fe2O3 values compared to granites around the world. Fe2O3 values of the samples depend on mafic minerals and independent Fe minerals such as magnetite within the rocks. According to electron microprobe analysis (EPMA), feldspars are mainly composed of SiO2, Al2O3, Na2O and K2O. The Central Anatolian feldspars have high K2O (over %14) and low FeO (less than % 0.05), thus they have high feldspar raw material potential in ceramic industry. Although alkali feldspar granites within AIS have promising potential to be used as feldspar raw material, they have low reserve due to their occurrence as dykes. On the other hand, Hacılı, Cefalık, Behrekdağ, Terlemez, Bayındır, Hamit and İdişdağı Suites have both good quality and high reserve for feldspar potential.
https://doi.org/10.19111/bulletinofmre.43819
Geochemistry and tectonic signifi cance of the ophiolitic rocks of the Yarpuz-Kaypak (Amanoslar, Osmaniye) area
No full textYarpuz-Kaypak (Osmaniye) region, located in Amanos Mountains, contains harzburgitic tectonites and mafic cumulates. The tectonites are represented by serpantinized harzburgites, whereas the cumulates are characterized by gabbronorite and gabbro compositions. The crystallization order within the cumulates is clinopyroxene, orthopyroxene plagioclase and amphibole. The major element compositions of the tectonites and cumulate rocks are consistent with formation in an arc-related tectonic setting. Trace element concentrations of these rocks exhibit large ion litophile element enrichments. Both geochemical and petrographic evidence suggest that the tectonite and cumulate rocks from the Yarpuz-Kaypak (Osmaniye) region represent the remnants of an oceanic lithosphere that formed in a supra-subduction zone tectonic setting during the closure of the Southern Neotethyan ocean and emplaced onto the northern margin of the Arabian platform in Late Cretaceous.
https://doi.org/10.19111/bulletinofmre.50139
The Gas hydrate potential of the Eastern Mediterranean basin
No full textGas hydrate exploration studies have increased substantially since last decade. Gas hydrate reservoirs are commonly found in the marine environment and permafrost. Studies related to natural gas hydrates in the Mediterranean Basin are rare compared to those released on the continental margins of the United States of America, Japan, India, China and Korea. This study provides an evaluation of the gas hydrate potential of the Mediterranean Basin using available literatüre data such as scientific drilling data (Ocean Drilling Program Leg 160 and Leg 161), sediment data, geothermal data, geochemical data, gas seepage data, mud volcano data etc., It is shown that there is a high producible gas hydrate potential (~ 98.16 standard trillion cubic meter) in the Mediterranean Basin. The Eastern Mediterranean basins have the highest gas hydrate potential due to its high amount of source gas potential and lower geothermal gradient compared to those in the Western Mediterranean. https://doi.org/10.19111/bulletinofmre.50227
Petrological and geochemical features of Biga Peninsula granitoids, NW Anatolia, Turkey
No full textIn Northwest Anatolia, widespread magmatism developed due to collision between Anatolide-Tauride platform and Sakarya continent during Late Cretaceous-Early Tertiary period. The granitoids in Biga Peninsula are products of post-collisional magmatism following the convergence of the northern branch of Neotethyan Ocean and developed in two different stages as Eocene and Oligo-Miocene. Eocene Karabiga, Güreci, Kuşçayır and Dikmen granitoids are granite and diorite-granodiorite; Oligo-Miocene Sarıoluk, Yenice, Kestanbol, Eybek, Evciler, Çamyayla and Alanköy granitoids are diorite, granodiorite, monzonite and Q-monzonite in composition. Metaluminous and peraluminous granitoids have similar geochemical variations and exhibit post-collisional geochemical signatures. Trace element patterns are almost similar to those observed in upper crust and GLOSS (Global Subducting Sediment) patterns with depletion in high field strength (HFS) elements (Nb, Ta, Ti, Zr, Hf). But, Oligo-Miocene Sarıoluk, Yenice-Çakıroba, Kestanbol, Evciler, Çamyayla, Alanköy and Eocene Karabiga, Güreci and Kuşçayır granitoids have higher Th and U contents relative to upper crust and GLOSS. Dikmen, Yenice-Hamdibey, Yenice-Eskiyayla and Eybek granitoids have lower Th content. Geochemical variations indicate that partial melting and fractional crystallisationcrustal contamination processes are effective in their genesis and evolution. Trace element ratios also indicate subduction signatures in their genesis and Rb/Ba, Rb/Sr ratios suggest mantle melting rather than crustal melting. Accordingly, post-collisional Biga Peninsula granitoids were derived from a previously metasomatised lithospheric mantle source, which was enriched during northward subduction and closure of the northern branch of Neo-Tethys Ocean beneath the Sakarya continent, since variations in Rb, Cs, Th, La and Sm reveal that lithospheric mantle was mesomatised by both aqueous fluids and sediment melts.
https://doi.org/10.19111/bulletinofmre.46652
Rare earth element (REE) resources of Turkey: An overview of their characteristics and origin
No full textThe Rare Earth Elements (REE) deposits and mineralization of Turkey can be divided into four types based on their geological setting and origin. First are deposits associated with carbonatite- alkaline magmatic rocks, rich in Light Rare Earth Elements (LREE). The best known examples are the Kızılcaören (Eskişehir) and Kuluncak (Malatya) deposits with TREE grades of 2.9% and 0.7% respectively, and typical enrichment of La-Ce. Lower grade REE mineralization at Keban (0.05% TREE) and Divriği (0.13% TREE) is associated with abundant fluorite and all four occurrences show similar ranges for homogenization temperatures and salinities for fluid inclusions in fluorite and REE profiles. The second type are Triassic shales and the bauxites formed from them in the Bolkardağı region. Enrichment of Heavy REE (HREE) is typical and TREE grades are about 0.15% in bauxites and its protolith. These occurrences are geochemically similar to “ion adsorption type” deposits associated with lateritic clay on the weathered granitic rocks of China. Third is the placer type, represented by the Çanaklı (Burdur) deposit which is enriched in U, Th and HREE and heavy minerals such as; magnetite, zircon and rutile and has an average grade of about 0.08% TREE. The fourth potential source of REE is phosphorites. These rocks host the world’s largest resources elsewhere, however the Cretaceous Mazidag deposits in Turkey are very low grade (40ppm TREE) and clearly uneconomic. Consideration of the environmental and health issues associated with exploitation and processing of REE has identified the more favorable outcomes associated with exploitation of the ion adsorption type of deposits and justification for further evaluation of the resources and processing technologies that would enable exploitation of REE-enriched bauxites in the Bolkardağı region. https://doi.org/10.19111/bulletinofmre.47120