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11.
Alper Baba 《Environmental Geology》2002,41(8):916-921
12.
Deniz Sanliyuksel Yucel Mehmet Ali Yucel Alper Baba 《Environmental Earth Sciences》2014,72(11):4311-4323
Can, a county in the province of Canakkale, is one of the most prominent coal mining districts in Turkey. Many mining companies have been operating coal deposits for power generation and district heating in this region since 1980. Generally, small and medium-scale mining companies operate for short periods and abandon the operational land without providing any rehabilitation. Human intervention in the natural structure and topography of the earth surface causes large holes and deterioration in these areas. Artificial lakes occur because of surface discharge and underground leakage into abandoned open pit mines with high lignite sulfur content (0.21–14.36 wt %). Furthermore, these lakes gain acidic character due to acid generation from pyrite oxidation. Acid mine lakes are highly acidic (pH < 3.05) and have elevated concentrations of \({\text{SO}}_{4}^{2 - }\) , Fe and some metals. The main objective of this study is to evaluate the environmental conditions and demonstrate the development of a monitoring system for their possible changes in the acid mine lakes of the open cast lignite mining area on a regional scale. For this purpose, the data received from remote sensing satellites were used. Areal change detection and perimeter changes of nine acid mine lakes caused by coal mining companies in Can from 1977 to 2011, were determined using Landsat, Quickbird and Worldview satellite images. As a case study, an area of 9 km2 was chosen for the variety of acid mine lakes. Using GIS software, satellite images were analyzed in time series, borders of acid mine lakes were digitized and converted into vector data format. At this stage, prior to the digitization, in order to create contrast on the satellite images, “stretch type” and “stretch values” were changed. The areal and perimeter changes were computed and presented via tables and graphics. In addition, thematic maps of the acid mine lakes were created and visualized. The results show that the number of acid mine lakes increased and these caused environmental risks due to their hydrochemical properties and areal increments. 相似文献
13.
14.
Hydrogeochemical and isotopic composition of a low-temperature geothermal source in northwest Turkey: case study of Kirkgecit geothermal area 总被引:1,自引:1,他引:1
Chemical and isotopic compositions of three hot springs and one cold spring in the Kirkgecit geothermal field, located 15 km
southwest of Canakkale-Biga in the northwest of Turkey, were monitored five times during 2005 and 2007. The physico-chemical
characteristics of the hot springs are average discharge 3–3.5 L/s, surface temperature 45–52°C, pH 8.9–9.3, and electrical
conductivity (EC) 620–698 μS/cm. The cold spring has a temperature of 12–13°C, pH 7.5–8.3, and EC 653–675 μS/cm. The hot waters
are Na-SO4 type, whereas the cold water is Ca-HCO3 type. Chemical geothermometers suggest that the reservoir temperature is around 80–100°C. The isotopic data (oxygen-18, deuterium
and tritium) indicate that the thermal waters are formed by local recharge and deep circulation of meteoric waters. 相似文献
15.
G. Nagendra Babu M. Sai Baba Mary K. Kumar Yamuna Singh P. V. Ramesh Babu P. S. Parihar 《Journal of the Geological Society of India》2013,81(4):447-450
For the first time we report bastnaesite and hydroxyl bastnaesite (lanthanum cerium fluoro-carbonate) from the Kanigiri granite. The host granitoids are of A-type and vary in composition from quartz syenites to peralkaline granites. Rare metal and rare earth-bearing minerals identified by X-ray diffraction (XRD) studies in Kanigiri granite are bastnaesite and hydroxyl bastnaesite, besides columbite-tantalite, monazite, fergusonite, thorite and euxenite. Petromineralogical studies have also revealed the presence of bastnaesite. The presence of bastnaesite in Kanigiri granite suggests that the host felsic rocks may also form a potential source for light rare earth mineral, bastnaesite, apart from the already known rare-metal minerals. 相似文献
16.
Yuhei Yamamoto Yoshio Takahashi Yutaka Kanai Yoshio Watanabe Tomoya Uruga Hajime Tanida Yasuko Terada Hiroshi Shimizu 《Applied Geochemistry》2008,23(8):2452-2461
The uranium LIII-edge XANES spectra for natural rocks at the concentration range of 0.96–124 mg kg−1 were measured using a log spiral bent crystal Laue analyzer (BCLA) combined with a multi-element Ge detector. It was found that the quality of the XANES spectra using the BCLA was greatly improved due to a reduction of interfering fluorescence from major components such as Rb and Sr. The ratio of signal to background intensities in the U LIII-edge XANES spectra increased by a factor of 2.9–17 with the use of the BCLA, which greatly enhanced the detection limit for the speciation of the oxidation states of U or the U(IV)/U(VI) ratio of natural samples. In addition, it was demonstrated that the fluorescence XANES method coupled with the BCLA enable determination of the speciation of U for various natural samples such as acidic igneous rocks, ferromanganese nodules, sediments, and some sedimentary rocks such as shale and limestone. 相似文献
17.
The tectono-thermal history of the Lewisian Complex in South Harris (South Harris Complex) was inferred from its geologic and metamorphic characteristics. The lithological assemblages and geochemical features of the complex suggest that its precursory rocks were composed of the subduction-related accretionary complex formed in the palaeo convergent margin. The complex has suffered the ultra-high temperature (UHT) metamorphism that was contemporaneous with the igneous activity to make the South Harris Igneous Complex (SHIC) and the subsequent continent-continent collisional activity. A similar complex recording the geological processes of the subduction, the UHT metamorphism and the collision has been recognized in the Lapland-Kola belt and New Quebec in the Palaeoproterozoic. This suggests an assembly of micro-continents to form the Palaeoproterozoic supercontinent in the North Atlantic region. 相似文献
18.
Natural Hazards - The deltaic coast of Myanmar was severely hit by tropical cyclone Nargis in May 2008. In the present study, a top-down numerical simulation approach using the Weather Research and... 相似文献
19.
Natural Hazards - A correction to this paper has been published: https://doi.org/10.1007/s11069-021-04687-9 相似文献
20.
Badri Bhakta Shrestha Hajime Nakagawa Kenji Kawaike Yasuyuki Baba Hao Zhang 《Natural Hazards》2012,61(2):577-602
Experience shows that debris flows containing large woody debris (driftwood) can be more damaging than debris flows without
driftwood. In this study, the deposition process of debris flows carrying driftwood was investigated using numerical simulations
and flume experiments. Debris-flow trapping due to driftwood jamming in a slit-check dam was also investigated. A numerical
model was developed with an interacting combination of Eulerian expression of the debris flow and Lagrangian expression of
the driftwood, in which the fluctuating coordinates and rotation of the driftwood were treated stochastically. The calculated
shapes and thicknesses of a debris-flow fan and the positions and orientations of the deposited driftwood on a debris-flow
fan were consistent with experimental flume results. The jamming of driftwood in a slit-check dam was evaluated based on geometry
and probability. The simulated results of outflow discharge and the proportion of driftwood passed through the slit-check
dam also agreed with the experimental results. 相似文献