Türkiye Jeoloji Bülteni

Abstract: Water samples from some springs which are used for drinking and irrigation purposes were collected inTendürek volcano region, located in the Eastern Turkey. Most of the spring water samples contain very high amountsof fluorine ranging from 2,5 to 12,5 ppm. The incisors and molars of a two-year-old sheep, obtained from the fluoroticconditions, exhibited brown to black staining and excessive and irregular wear. During the surveying of the area, dentalfluorosis was observed in the local population by the medical team. Dilution of fluorine rich waters with other suitablewaters down to a safe level was recommended to alleviate effects of fluorine on livestock and human health and alsoon the contamination of soils and pastures.The following units have been identified around the Tendürek mountain which is one of the young volcanoes ofAnatolia: Metamorphic rocks which are composed of micaschists, marble and quartzites and are thought to be Paleozoicin age, crystalline limestones which are Permo-Carboniferous in age, Upper Cretaceous ophiolites containing spilites,serpentinites and limestones, Paleocene limestones, Eocene flysch and limestone, sandstone, claystone, siltstone andlimestones of Miocene age, and Tertiary lava flows. The whole succession is covered by young basaltic lava flowsof Tendürek volcano.Spring waters are coming from these lavas, limestones in flysch and ophiolite, and marbles in basement. Tensamples were analysed from these springs. High F- waters are NaHCO3 type, and low F- waters are Ca-MgHCO3type. F- , which might be transported by fumaroles - escaped from devitrified lavas, could be held on the surfaceof some minerals and then exchanged with OH- of underground waters with high pH. At the end of this hypotheticprocess these waters might be discharged as high F- water at the foothills of Tendürek volcano.

Abstract: The Mortaş bauxite deposit is on the Western Taurus mountains of Turkey. It occurs along the unconformity between Lower and Upper Cretaceous limestones. The deposit is mainly boehmitic. In addition to boebmite,diaspore, gibbsite, kaolinite, montmorillonite, hematite, goethite, and anatase are also present in lesser amounts. Thedeposit also contains mineraloids such as alumogels, siderogel, and hematogelite.Among chemical constituents Al2O3 TiO2, and L.O.I have high positive Al2O3. SiO2 has differe correlation and showsimilar areal variation Fe2O3 is negatively correlated with Al2O3. SiO2 has a diffrent distribution pattern from the aforesaidchemical constituents. The mineralogical and chemical data indicates that the bauxite of the Mortaş deposit is derived fromlimestone. 

Abstract: Valensole basin is situated in the southeast part of France and is formed as a subsiding basin on theMesozoic limestones. It contains more than 1000 m of mostly clastic sediments which are Tertiary-Quaternary in age.In the eastern part of the basin which was studied by the present writer, the red coloured "Valensole conglomerates" pass laterally in the white coloured "Puimoisson marles". These formations have been overlain by "Cryoclasticpebbles". These units are the youngest continental formations of the area which has been studied.In previous studies, it has been accepted that all these three units pass laterally in each other. Some workershave thought that they are Pliocene in age, but the other workers have suggested that they are Quaternary in age.This work has made it clear that the characteristic fossils which have been found in the Puimoisson marls indicatethat the Valensole conglomerates and the Puimoisson marls are definitely Upper Pliocene in age. The Cryoclastic pebbleswhich lie on top of the other units, represent a different faeies and are thought to be a glacial deposit in a Quaternaryage.Puimoisson marls were deposited in a lake environment which were developed in the Valensole basin here and there,during the Upper Pliocene time. At the same time southwesterly flowing rivers which were cut in the Mesozoic andLower Cenozoic units in the east, deposited the fan-shaped Valensole conglomerates in the basin.During a glacial period in Quaternary the cryoclastic pebbles were formed through frosting and melting processeson the Mesozoic-Lower Cenozoic units situated to the east of the basin. These pebbles were deposited as an alluvialcone in the basin after being transported by the southwesterly flowing rivers as in the case of the Upper Pliocene.

Abstract: Six new spedes of Alveolina are described from the Polatlı region. Alveolina polathensis n.sp. (Upper Ilerdian), A.blumenthali n.sp. (Middle Herdian) belong to the group of Alveolina ellipsoidalis; A. bayburtensis n.sp.(Middle-UpperCuisian), A. sakaryaensis n.sp. (Middle Ilerdian) belong to the group of Alveolina Canavarii; A. ankaraensis n.sp.(Middle Ilerdian) belong to the group of Alveolina pasticillata; A. haymanaensis n.sp. (Lower Cuisian) belong to thegroup of Alveolina elliptica.

Abstract: Study area is situated within the triangle of Bayburt - Erzincan - Aşkale, trending roughly in a NE-SW directionand mainly comprising of Liower Tertiary (Ypresian) turbidites (750-1000 m in thickness). It appears that these turbidites havebeen deposited by paleo-currents flowing mainly from SW to NE. Some turbidity currents were probably initiated by submarineslumps which started at the northern and southern edges of the basin, and moved downslope towards the axis where theyturned paralel to it and continued along the basin plunge towards NE.

Abstract: Systematic description and stratigraphical distributions of the species of Nmıımulites, Assilina and Alveoliııa have been studied in the Upper Paleocene (Ilerdian), Lower Eocene (CUisian) and Middle Eocene (Lutetian) sediments of the region between Çayraz and Yeşilyurt village, all situated in the north of Haymana (south of Ankara), inthe otherhand the stratigraphy of the region is given shortly,The rock units of Upper Cretaceous (Maestrichtian), Paleogene and Neogene ages crop out in the region. Maestrichtian sequence is composed of alternatlng sandstone, marl, congtomerate and sandy llmestone. The upper part of the Maestrichtian sequence contalns abundant foraminifera, species, such as Orbitoides mediu-s (d`Archiac), Siderolites calcitrapoides Lamarck, Ouvillierina Bözerii Sirel, in large amount. Lower Paleocene (Monttan) sequence overlies comformablythe Maestrichtlan, and it is composed of an alternating of alga! limestones and marı. The algal limestones contaln speclcsof the foraminifera such as Laf/itteina bibensiB Marle and Ouvillieri.ııa n.sp. Middle Paleocene (Thanetian) sedlmeotsoverlieB comformably the Montian and it is composed of sandstone, marl and alga! limestone. The alga! llmestone ofthe Thanetian sequence contain foraminifers such as Alveoıitıa .(Glomalveolina) prhnaeva Reichel and DiscocıJcliııa Bcttnesi Douville.The Upper Paleocene (Ilerdian) sequence overlies comformably the Middle Paleocene (Thanetıan) and ıt ıs com-posed ofsandstone, conglomerate, marl and sandy limestone. The sandstones and sandy limestones of the sr-quence contaln species of theforaminifera such as NummıditesfraaBi dela Harpe, N. exilis Douvill .Alvcofüıa cu-cumlformis Hottınger, The Ilerdlan se,quenceIsunconformably overlaln by the clayey and sandy llmeetones, marl nnd conglomerate of Lower Eocene (Cu!slan) age, the Culslansedlments Is characterfzed by Num1nulites pTanulatıuı (La-marck), N. irregularis Deshayes, N. partschi de la Harpc, Assiliııaplacentula (Deshayes), Alv`oolinabayburtcıısls Slrcl andAlv. canavarii Checchla - Rlspoll. TheMlddlcEocenc (Lutetian) sequcnceoverlles com!ormably thc Cı,ılıılıın sc· dlments and it Is composed of an alternatıon of clayey llmestone and marl. The cıayeyllmestones are characterlzed by Nummulites helveticııs Kaufmann, N. laevigatus (Bruguiere), N. pinfoldi Davies, Ass. exponeııs(Sowerby) and.ııss.spiro deRolssy. The Lutetian sequence ıs unconformably overlaln by the lacustrine llmestone andconglomerateof Ncogcne age, 

Abstract: Data based on a study of more than 2500 primary and secondary fluid inclusions in transparent oreand gangue minerals are given. The data include measurements on the temperature, pressure, density and salinity ofthe inclusions present in the Southern Bulancak Deposits, Eastern Black Sea Ore Province of Turkey.The inclusions were moderately saline, salinity varying within the range 13.2 equivalent wt. % NaCl to almostfresh water indicated by a density change from 0.74 gr/cm3in the early vein stage to 0.98 at the end of the basemetal sulphide stage. These variations may reflect the mixture of deeply circulating meteoric waters with rising,saline, hydrothermal fluids.Homogenization temperatures ranged from ca 80°C to 340°C. Inclusions show a temperature rise from ca 230to 330°C in the early vein stage, and eventually boiling conditions were reached. At a later stage the fluids cooledfrom 330°C to ca 80°C in the base metal sulphide stage. The highest temperatures were obtained from the Tekmezar Group of veins, in comparison to the Danköy group of veins, indicating a horizontal temperature zoning.Evidence of boiling conditions and geological data suggest that the depositional pressures were 85-90 bars indicating a 1000 m hydrostatic load.Data obtained from isotherms indicates that the ore-bearing fluids rose along NW-SE trending faults.Fluid inclusion studies combined with geological, data, are considered to be useful parameters in mineral exploration to pinpoint richest part of the orebody. 

Abstract: Asbestos deposits of Mihalıccık region occur at local shear zones along the contact between metamorphicand serpentinized ultrabasic rocks. Metamorphic rocks were intensely laminated, serpentinites were fractured and forcefully injected in metamorphic rocks at such shear zones. Metamorphic rocks are chloritized, and fractures withinserpentinites are filled with picrolite, asbestos, talc and quartz. Such mineralogical changes are caused by frictional heatand solutions circulating within fractures at such shear zones. Glaueophane has two distinct origin in this area: it hasdeveloped within the metamorphic rocks as a result of burial metamorphism on a regional scale and locally, it hasdeveloped with metamorphic rocks around shear zones due to heat and circulation of solutions. 

Abstract: A large-scale `in-situ` shear test, employed in the construction of a Brazilian power-navigation projecton the Parana River, was analyzed by a "discontinuum" finite element approach. This was considered particularlyappropriate for simulation inasmuch as horizontal and vertical displacements were recorded as a function of appliedload at a number of points on the test block. In the field test, described in detail by Ruiz and Camargo (1966),resistance between sandstone and an overlying basaltic flow was determined. Inversion of vertical displacementsobserved by Ruiz and Camargo in their field test, are also seen in the theoretical results obtained by the finite elementapproach. However, the theoretical results suggest that inversion of vertical displacements can also occur as a consequence of elastic deformation. The inversion effect can be produced as a consequence of the reorientation of the elasticdisplacement field during the progressive slip along the base of the shear block. 

Abstract: The Taurus mountains contain the rock units which were deposited from Cambrian to Tertiary. Withinthis belt there are different units representing different basin conditions. The following units were distinguished andwere named by the author: Bolkardağı Unit, Aladağ Unit, Geyik dağı Unit, Alanya Unit, Bozkır Unit and Antalya Unit.These units can be distinguished and differentiated from each other by their stratigraphic position, character ofmetamorphism, the rock units which they contain and theil present structural position. These units extend laterallyabout hundreds of kilometers with tectonic contacts between them and commonly they form allochthonous covers oneach other. The Bolkardağ, Aladağ, Geyik dağı and Alanya units contain carbonates and detrital rocks which werethought to be deposited in a shelf environment. On the other hand, the Bozkır and Alanya units contain deep seasediments, ophiolites and submarine basic volcanic rocks.