Mehmet Önal

Geology and trona potential of the middle Miocene Gürün (Sivas) basin, Central Anatolia, Turkey

Gürün (Sivas) basin, extending along east-west direction, contains a volcano-sedimentary sequence of up to 1222 m thick. The middle Miocene sedimentary sequence rest with angular unconformity on the basement rocks, which consist of limestone and flysch sediments ranging in Triassic-Jurassic-Cretaceous and middle-upper Eocene. The sequence has been subdivided into Gürün Formation and Karadaĝ Volcanics. The Gürün Formation consist of four members in ascending order: Kavak, Gökpinar, Çayboyu and Terzioĝlu members. Trona occurences are placed within the Terzioĝlu member, alternating with bituminous shale, mudstones and tuffs; whereas the lignite deposits occured in the Çayboyu member of the Gürün Formation.The Miocene sedimentary rock units are laterally and vertically gradational. Karadaĝ volcanics, located in the eastern and northern parts of basin, interfinger with the upper parts of the Terzioĝlu member, and also cut the whole rock units. The thickness of the sequence increases towards the northern and eastern sides where the basin was faulted. According to spor and pollen fossils, the age of sedimentary rock units is middle Miocene. The rock units were deposited in alluvial, fluvial, lacustrine and playa-lake environments.The middle Miocene sedimentary sequence, which were deposited under the control of a tectonic regime. In the region, gravity tectonic, which is characterized by the growth faults, began to developed in the beginning of middle Miocene. The growth faults, which were developed at the northern margin of the basin, controlled the deposition during the middle Miocene. Gürün basin was affected by the extensional tectonic regime changed to a compressional regime during the late Miocene time. During this new tectonic phase, NE, SW compressional regime occuring in the region probably originated from the movement of the East Anatolian Fault.The bituminous shales of the Terzioĝlu member contains starkeite, hexzahydrite, dolomite and calcite. Na-carbonate (trona) leachings are rather common within the lower and middle parts of the Terzioĝlu member. Sodium carbonate minerals occuring in the basin are nahcolite, pirssonite, gaylusite and shortite. The beds consisting of the Na-carbonate minerals grade into mudstones and clayey limestones towards the edges of the basin.The Gürün middle Miocene basin is mainly filled by clastics and products of adjacent volcanic activity which was centered at the east and north of basin. The most likely sources of sodium for the formation of Na-carbonate (trona) accurences are thermal springs, tuff interbedded with the sediments, and extensive the middle Miocene volcanic rocks interfingering with the sedimentary rocks in the eastern and northern parts of the basin.

Sedimentology and geochemistry of the middle miocene playa lake evaporites in the Gürün basin (S of Sıvas), central Anatolia, Turkey

The Gürün basin is a half graben filled by alluvial, fluvial and playa-lake deposits of the Gürün Formation accumulated under the N−S direction extensional tectonic regime and volcanic rocks.The Gürün Formation is divided into four members such as the Kavak, Gökpmar, Çayboyu and Terzioğlu members, and the Çayboyu Member has two different evaporitic occurrences such as selenitic and satin spar. During the first phase of evaporite deposition, selenitic gypsum crystals in 5 to 15 cm thick layer within the dolomitic mudstones were formed. The second evaporitic phase consists of four different levels of cavity filling within the sandstones and shale alternation at the upper part of sequence originated as 5 to 10 cm sized satin-spar gypsum crystals with white colored, partly orientated, fibrous-radial shaped. XRF major, minor and some rare elements analyses (La, Ce, Ta, W and U) and low87Sr/86Sr (‰) and δ34S (CDT) values indicate that meteoric and volcanic solution occasionally mixed with the lake water.In addition, low δ18O (SMOW) values in the continental evaporate could be interpreted as mixing of fresh water with the playa lake environment. Selenitic gypsum in the Çayboyu Member of the Gürün Formation was precipitated from ground water-brine water rich in humic acid during periodic desiccations of in the shore-lake plain.

Co-liquefaction Behaviour of Elbistan Lignite and Olive Bagasse

In the present study, co-liquefaction potential of Elbistan lignite and Balikesir olive bagasse were investigated by direct coal liquefaction process. The olive bagasse is a cheap and abundant biomass, so it is used to decrease the cost of oil production from the lignite. The effect of blending ratio of the lignite and the olive bagasse on liquefaction conversion and oil yield were investigated. Characterization studies of the starting materials were done using XRD, FTIR, DTA/TG and elemental analysis. Elemental compositions of liquefaction products were also determined and the composition of the obtained oil was identified by GC/MS. DTA and TGA results indicated the synergistic effect of the lignite and the olive bagasse and maximum oil conversion (36 %) was obtained from 1:3 blending ratio of lignite: olive bagasse. The results showed that the obtained oil was paraffinic-low waxy oil with 22.5 MJ/kg of calorific value and 95 g/cm3 density.

INVESTIGATION OF THE EFFECTS OF DETONATIONS NEAR THE BATTALGAZİ CAMPUS OF İNÖNÜ UNIVERSITY, MALATYA, TURKEY ON SOIL SHALLOW-DEPTH

This study was carried out in the Inonu University Battalgazi Campus and aimed to investigate the effects of detonations in the area used by the Turkish Armed Forces as a shooting range on Campus Site shallow-depth, by using the Multielectrode Vertical Electrical Resistivity (MVER) method. Combat aircrafts from the Turkish Armed Forces 7 th Main Jet Base Command weekly carry out two shooting tests in the region. In the selected region, two MVER applications, prior to detonation and three months after detonation, were carried out in the same location and direction and measurements were compared to each other. The results showed that the shooting tests affected the shallow-depth.

The Zeolite Deposit of Hekimhan in the Malatya Basin

Zeolite deposits in the Malatya Basin which is formed of the Yuksekova Group were investigated in the present study. The zeolites were occurred in the two layers: the lower zeolite layer and the upper zeolite layer of the Sankiz Formation of Campanian-Maastrichtian age within the flysch like sediments at Hekimhan in the northern part of the Malatya Basin. Characterization studies of the zeolite samples were done by XRF, XRD and SEM images and the results showed that the main structures of the zeolites were clinoptilolite-(Cs), heulandite and calcite and the geological occurrences of zeolite is in marine environments.

Usability of Malatya Pyrophyllite in the Traditional Ceramic Industry

In the present study, the usability of the pyrophyllite in the traditional ceramic industry was investigated. The raw pyrophyllite was obtained in Malatya, Turkey. The characterization of the raw pyrophyllite and the prepared ceramics which were heated at the different temperatures in oven (800, 900, 1000 and 1100 °C) were done by XRF, XRD, FTIR, SEM and the main physical properties, like total shrinkage, water absorption capacity and compression strength were determined. As a result of experimental studies; the raw pyrophyllite had to be mixed with the feldspar and another clay (Unye clay) with having high plasticity in order to shape easily and a high water resistance. The optimum receipt was found as 70 wt % pyrophyllite, 20 wt % Unye clay and 10 wt % feldspar. The main properties of the obtained ceramics were specific white baking colour and high temperature resistance properties.

Mineralogical and Chemical Characterization of Acidic Pumices Outcrop North of Lake Van

In the present study, mineralogical, physical and chemical characteristics of the pumice located in North of Lake Van locations were investigated to find an applicability of them for cement and textile industry. Characterization studies of the pumice samples were carried out by thin section, SEM, XRF, XRD and FTIR analysis. In addition, the bulk density, Hard Grove Index (HGI), pozzolanic activity and reactive silica of the pumice samples were determined. The overall results showed that the pumice samples, which might be an eruption product of Mount Suphan, had an amorphous structure and rhyolite composition in high calc- alkaline series. The chemical compositions and physical properties indicated that the pumice samples could be used in cement and textile industry.