Organic Material and Trace Elements of Bituminous Rocks in the Ozankiiy Field, Ankara, Turkey          下载免费PDF全文

Saday Azadoglu ALIYEV Ali SARI 《《地质学报》英文版》2007,81(4):658-667

Bituminous rocks in the Ozankoey （Ankara） field are different from those of the Paleocene- Eocene Mengen and Giineytepe （Bolu） regions in metal enrichment levels. Organic carbon （Corg） content of organic material-rich rocks in the Ozankoey （Ankara） field is 3.66-40.72% wt averaging 14.34%. The dominant organic materials are algae/amorphous accompanied by minor amount of herbaceous material （The dominant kerogen type is Type-I with a limited amount of Type-Ⅱ kerogen.）. The bituminous rocks in the Ozankoey field are enriched in heavy metals such as Ni, Mn, As and Cr. In comparison with the average enrichment values of dements, Ni, Mn, As and Cr in bituminous shales of the Ozankoey field are as about 4.38, 14.93, 10.90 and 5.58 times as average values. The average concentrations of these heavy metals are also as high as 215× 10^-6, 828 × 10^-6, 58.54 × 10^-6, and 148 × 10^-6 respectively. In addition, sorption properties of day and organic materials are also important for metal enrichments in the bituminous shales.  相似文献   

Eocene tonalite–granodiorite from the Havza (Samsun) area,northern Turkey: adakite-like melts of lithospheric mantle and crust generated in a post-collisional setting     

Irfan Temizel  Mehmet Arslan  Cem Yücel  Emel Abdioğlu Yazar  Abdullah Kaygusuz  Zafer Aslan 《International Geology Review》2020,62(9):1131-1158

ABSTRACT

Eocene intermediate to felsic plutons of different sizes and compositions are widespread in the Eastern Pontides Orogenic Belt in northern Turkey. Of these, the Ta?l?k Tepe pluton in the Havza (Samsun) area is fine-to-medium-grained, with granular, porphyritic, and micrographic textures, and include mafic microgranular enclaves (MMEs). LA-ICP-MS U-Pb zircon dating yielded emplacement ages of 42.9 (± 1.4) and 40.5 (± 1.3) Ma for the host granodioritic pluton and the dioritic MMEs, respectively. Petrochemically, the host pluton has I-type, high-K calc-alkaline, and metaluminous-to-slightly peraluminous features (A/CNK = 0.95–1.06). The host pluton also shows geochemical features of adakite-like rocks with high SiO₂ (67–68 wt%) and Al₂O₃ (15.5–16.0 wt%) content and Ba/La (17–23), Sr/Y (40.7–61.6), and La_N/Yb_N (14.4–23.7) ratios and low Y (8.2–9.9 ppm) and Yb_N (3.1–4.4) contents. Whole-rock major and trace element variations suggest that fractional crystallisation played a significant role in the pluton evolution. The N-MORB normalised trace element patterns of the pluton are similar to those of MMEs with enrichment in large-ion lithophile elements, Th and Ce, and negative Nb and Ti anomalies. Chondrite-normalised rare earth element plots show moderate-to-highly enriched concave patterns (La_N/Lu_N = 14.2–21.6) with insignificant negative Eu anomalies (Eu_N/Eu* = 0.86–1.14), all of which imply hornblende fractionation during magmatic evolution. The pluton samples have ⁸⁷Sr/⁸⁶Sr ratios of 0.704767 to 0.704927, ¹⁴³Nd/¹⁴⁴Nd ratios of 0.512767–0.512774, εNd values of (+2.52) – (+2.65), and δ¹⁸O values of 7.9–9.7‰. The isotopic compositions of the host pluton and MMEs are similar to I-type granitoids derived from mantle sources. The MMEs show incomplete magma mixing/mingling, representing small bodies of mafic parental magma. Combined with regional studies, these new data suggest that the parental magma of the studied adakite-like pluton was generated from the lithospheric mantle and then modified by fractional crystallisation and assimilation in a post-collisional setting.  相似文献   

The Spectrum and Dips of RE 0751+14: A Joint Evaluation of ROSAT and ASCA Archival Data     

Ümit Kiziloğlu  Altan Baykal  Murat Alev  Ersin Göğüş 《Astrophysics and Space Science》1998,259(2):191-203

Using archival ASCA and ROSAT observations of RE 0751+14, X- ray energy spectra, pulse profiles and the results of pulse timing analysis are presented. The energy spectra are well-fitted by a blackbody model at low energy and a Raymond-Smith model at high energy, together with a partial covering absorber. A fluorescence emission line at 6.4 keV with an equivalent width ∼ 220 eV was resolved for the first time. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Asteroseismic modelling of the solar-like star β Hydri     

G. Doğan  I. M. Brandão  T. R. Bedding  J. Christensen-Dalsgaard  M. S. Cunha  H. Kjeldsen 《Astrophysics and Space Science》2010,328(1-2):101-104

We present the results of modelling the subgiant star β Hydri using seismic observational constraints. We have computed several grids of stellar evolutionary tracks using the Aarhus STellar Evolution Code (ASTEC, Christensen-Dalsgaard in Astrophys. Space Sci. 316:13, 2008a), with and without helium diffusion and settling. For those models on each track that are located at the observationally determined position of β Hydri in the Hertzsprung-Russell (HR) diagram, we have calculated the oscillation frequencies using the Aarhus adiabatic pulsation package (ADIPLS, Christensen-Dalsgaard in Astrophys. Space Sci. 316:113, 2008b). Applying the near-surface corrections to the calculated frequencies using the empirical law presented by Kjeldsen et al. (Astrophys. J. 683:L175, 2008), we have compared the corrected model frequencies with the observed frequencies of the star. We show that after correcting the frequencies for the near-surface effects, we have a fairly good fit for both l=0 and l=2 frequencies. We also have good agreement between the observed and calculated l=1 mode frequencies, although there is room for improvement in order to fit all the observed mixed modes simultaneously.  相似文献   

CCD BV and 2MASS photometric study of the open cluster NGC 1513     

S. Bilir  T. Güver  I. Khamitov  T. Ak  S. Ak  K. B. Coşkunoğlu  E. Paunzen  E. Yaz 《Astrophysics and Space Science》2010,326(1):139-150

We present CCD BV and JHK _s 2MASS photometric data for the open cluster NGC 1513. We observed 609 stars in the direction of the cluster up to a limiting magnitude of V∼19 mag. The star-count method showed that the centre of the cluster lies at α ₂₀₀₀=04 ^h 09 ^m 36 ^s , δ ₂₀₀₀=49°28^′43^″ and its angular size is r=10 arcmin. The optical and near-infrared two-colour diagrams revealed the colour excesses in the direction of the cluster as E(B−V)=0.68±0.06, E(J−H)=0.21±0.02 and E(J−K _s )=0.33±0.04 mag. These results are consistent with normal interstellar extinction values. Optical and near-infrared Zero Age Main-Sequences (ZAMS) provided an average distance modulus of (m−M)₀=10.80±0.13 mag, which can be translated into a distance of 1440±80 pc. Finally, using Padova isochrones we determined the metallicity and age of the cluster as Z=0.015±0.004 ([M/H]=−0.10±0.10 dex) and log (t/yr)=8.40±0.04, respectively.  相似文献   

Carbon isotopes and iodine concentrations in a Mississippi River delta core recording land use, sediment transport, and dam building in the river's drainage basin   总被引：1，自引：0，他引：1  

Santschi PH  Oktay SD  Cifuentes L 《Marine environmental research》2007,63(3):278-290

Sedimentary material from coastal and nearshore areas in the Mississippi Delta region are comprised of different organic carbon sources with diverse ages that require isotopic and elemental records for resolving the various sources of plant residues. Carbon isotopic ((13)C, (14)C) values were used to differentiate contributions from plants using the C3, C4, and/or CAM (crassulacean acid metabolism) carbon fixation pathways., and iodine concentrations indicated that wetland plant residues are a significant source of organic carbon in a sediment core from the Mississippi River delta region collected at a 60 m water depth. This sediment core had been extensively described in Oktay et al. [Oktay, S.D., Santschi, P.H., Moran, J.E., Sharma, P., 2000. The (129)Iodine Bomb Pulse Recorded in Mississippi River delta Sediments: Results from Isotopes of I, Pu, Cs, Pb, and C. Geochim. Cosmochim. Acta 64 (6), 989-996.] and significantly, includes unique features that had not previously been seen in the marine environment. These special features include a plutonium isotopic close-in fallout record that indicates a purely terrestrial source for these sediment particles and the elements associated with it, and a distinct iodine isotopic peak (as well as peaks for plutonium and cesium isotopes) that indicate little bioturbation in this core. Our carbon isotopic and iodine data can thus be compared to published records of changes in drainage basin land use, river hydrology, and hydrodynamic sorting of suspended particles to elucidate if these changes are reflected in nearshore sediments. This comparison suggests a significant contribution for organic carbon (OC) from C4 plants to these sediments during the 1950's to early 1960's. Relative older carbon isotopes, and episodically high iodine concentrations (up to 34 ppm) were observed during this time period that (1) indicate sediment deposition that is coincident with the times of major hydrological changes induced from dam and levee building in both the upper and lower reaches of the Mississippi River drainage basin, and (2) suggest episodic organic carbon deposition from wetland plant residues.  相似文献   

Field evidences of secondary surface ruptures occurred during the 20 February 1956 Eskişehir earthquake in the NW Anatolia     

Faruk Ocakoğlu  Sanem Açikalin 《Journal of Earth System Science》2010,119(6):841-851

Surface rupture and source fault of the 20 February 1956 Eskişehir earthquake have been a matter of debate that potentially contributes towards the understanding of the active deformation and seismic risk in the highly populated NW Anatolia. Field observations on the two fault segments (namely Kavacık and Uludere faults) in the north of the Eskişehir graben revealed evidences of co-seismic surface rupture and mass movements during the Eskişehir earthquake. Surface rupture was observed as a 2.5m wide, a 100m long and ca. 20 cm deep asymmetric depression in the Gümüşlü valley, 2 km east of the Uludere village. A trench dug on this depression confirms a prominent high-angle south dipping fault (dominantly left lateral strike slip) and two faint north-dipping antithetics as clear noticeable shear zones in organic-rich thick soil. Mass failures are particularly observed in spring depressions filled with loose torrent and carbonaceous material in front of the fault scarp. Some rock slides of several tens of meters in size that obviously require significantly high ground shaking were also developed on steep fault scarps. The orientation of the principal stress tensor as deduced from the surface rupture of the Eskişehir earthquake displays clear inconsistency with the geometry of prominent faults in the area. We concluded that this disagreement may be explained by a curved surface rupture. The western and eastern tips of this rupture are EW trending and the probable NW-running part in the middle would correspond to the bounding zone between two right-stepping faults.  相似文献   

A combined hydrologic and hydraulic modeling approach for testing efficiency of structural flood control measures   总被引：3，自引：2，他引：1  

Gülay Onuşluel Gül  Nilgün Harmancıoğlu  Ali Gül 《Natural Hazards》2010,54(2):245-260

The necessity of estimating the degree and spatial extent of positive impacts with regard to protecting communities and properties through potential flood control projects can be considered one of the main reasons for performing flood modeling. This paper presents an overall systematic approach based on the simulation of some extreme event conditions, using a hydrological model to generate the resulting river flows and then using a hydraulic modeling exercise to decide upon floodplain evolution in the case-study area, Bostanli river basin, which has been under the threat of flooding for many years. The potential serviceability of the planned Bostanli Dam in the study area was examined by using the HEC-HMS and HEC-RAS modeling tools, both integrated with GIS functions for spatial operations. The results indicate that the dam construction as planned would have a somewhat positive impact as a potential flood control measure, since it seems to decrease the flood peaks of 68.9 and 158.7 m³/s (that would potentially be generated by 100- and 500-year storm events under current conditions) to 65.5 and 150.7 m³/s (when the dam is in operation), respectively. However, this seems to contribute little to the overall flood mitigation performance in the basin.  相似文献   

Microthermometric and stable isotopic (O and H) characteristics of fluid inclusions in the porphyry related Çöpler (İliç - Erzincan) gold deposit,central eastern Turkey     

Oktay Canbaz  Ahmet Gökce 《Central European Journal of Geosciences》2014,6(2):139-147

The Çöpler gold deposit occurs within the stockwork of quartz hosted by the Çöpler granitoid (Eosen) and by surrounding metasediments of Keban metamorphic (Late Paleozoic - Early Mesozoic) and the Munzur limestones (Late Carboniferous - Early Cretaceous). Native gold accompanied by small amounts of chalcopyrite, pyrite, magnetite, maghemite, hematite, fahlerz, marcasite, bornite, galena, sphalerite, specular hematite, goethite, lepidochrosite and bravoitic pyrite within the stockwork ore veinlets. In addition, epidote (pistazite - zoisite), garnet, scapolite, chlorite, tremolite/actinolite, muscovite and opaque minerals were determined within the veinlets occurred in skarn zones. The study of fluid inclusions in quartz veinlets showed that the hydrothermal fluids contain CaCl₂, MgCl₂ and NaCl and the salinities of the two phases (L+V) inclusions range from 1.7 to 20.6% NaCl equivalent. Salinity values up to 44% were determined within the halite bearing three phases inclusions. Their homogenization temperature values have a wide range from 145.0 to 380.0°C, indicative of catathermal/hypothermal to epithermal conditions. The δ ¹⁸O and δD values of the fluid inclusion waters from the Çöpler granitoid correspond to those assigned to Primary Magmatic Water, those from the metasediments of Keban metamorphics fall outside of the Primary Magmatic and are within the Metamorphic Water field. A sample from a quartz vein within the skarn zone hosted by the Munzur limestones has a particularly low δD value. The results suggest that fluids derived from the granitoids were mixed with those derived from the metasediments of Keban metamorphics and the the Munzur limestones and resulting in quartz veinlets in these lithologies and the formation of stockwork ores. In view of the occurrence, the features described and processes envisaged for this study area may be applicable in similar settings.  相似文献   

Designing a flood forecasting and inundation-mapping system integrated with spatial data infrastructures for Turkey     

Halil Akıncı  Sevsin Erdoğan 《Natural Hazards》2014,71(1):895-911

Turkey currently lacks a fully functional flood forecasting system (FFS). However, the studies necessary for establishing such a system are still being performed by the Turkish State Meteorological Service. The main purpose of this study was to determine the technical architecture of the FFS intended to be developed in Turkey and to design a flood forecasting and inundation-mapping system integrated with spatial data infrastructure (SDI). Because SDIs provide interoperability among the institutions by enabling collective use of data and services, this enables decision makers to take correct and rapid decisions regarding the forecasting. In the design of the system, the Web services architecture presented by the open geospatial consortium that develops international standards for SDI realizations was taken as a basis. Designed with flexibility and an expandable architecture, the system will enable instant access to up-to-date data from different institutions through Web services and meets the requirements of a real-time FFS. While the criteria requiring the expansion of the designed system were explained, its implementation was left for future studies.  相似文献