This study focuses on the Etili and Comakli openpit coal mines, where mine lakes are most densely located within the Can Coal Basin (northwestern Turkey). The aim of our study was to create 3D terrain models of these mine lakes using high-resolution images from an unmanned aerial vehicle (UAV) and to quantify areal changes linked to anthropogenic and meteorological effects over the study period. In November 2014 and October 2015, a DJI F550 hexacopter was flown at elevations of 30-100 m, and images were acquired using a 12-megapixel camera. Nineteen flights were completed, with each flight acquiring between 109 and 554 images. 3D modeling of UAV images was carried out with Agisoft software, using the most common structure from motion algorithm. Its workflow, involving image matching, georeferencing, digital elevation modeling, orthomosaics, 3D point cloud, and 3D textured model creation, was used to generate our 3D terrain model for the mine lakes. Orthomosaics with 1-6 cm/pixel resolution were used to assess areal change in the mine lakes. Area was calculated using two different methods (digitization and classification) within the ArcGIS package; results of these two methods were compared. Our UAV study of open-pit mines rapidly and precisely determined changes in topography linked to anthropogenic and meteorological effects. It also proved to be an effective method of visualizing such effects over the short term.
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 SO 2À 4 , 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 km 2 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.
'nde yer alan Kestanbol jeotermal alanı, Biga Yarımadası'nın plütonik yükselimleri ile komşu metamorfik kayaçlarının kontağında bulunmaktadır. Bu alan aynı zamanda Kuzey Anadolu Fayı'nın güney kolunun batıya olan uzantılarını temsil eden DKD-BGB uzanımlı sağ yanal doğrultu atımlı bir fay segmenti ile kontrol edilmekte olup, Biga Yarımadası'ndaki en yüksek sıcaklığa sahip jeotermal alanlardan biridir. Kestanbol jeotermal alanında bulunan sondajdan çıkan jeotermal akışkan tesisin ısıtılması, termal turizm ve balneolojik uygulamalarda kullanılmaktadır. Jeotermal akışkan çevreye düşük debi ile sürekli olarak sızmakta ve ayrıca kaplıcanın atık suyu Ilıca deresine deşarj edilmektedir. Bu çalışmada, Kestanbol jeotermal alanında yer alan sondaj ve kaynakların hidrokimyasal karakteristiği belirlenerek, toprak ve dere sedimenti üzerindeki çevresel etkileri ve antropojenik kirlilik yaratma potansiyeli değerlendirilmiştir. Kestanbol jeotermal akışkanının sıcaklık, elektriksel iletkenlik (EC) ve pH değerleri sırasıyla 59,5-74,1ºC, 30,3-35,5 mS/cm ve 6,45-6,71 arasındadır. Jeotermal kaynaklar NaCl su tipinde olup, ortalama NaCl konsantrasyonu 19511 mg/l'dir. Kestanbol jeotermal akışkanının yüksek EC değeri ve toplam çözünmüş katı madde içeriğinin yanı sıra Na + , Cl-, B, Ba, Fe ve Mn konsantrasyonu bakımından TS 266'ya göre izin verilen maksimum değerlerin üzerindedir. Ayrıca jeotermal akışkanın EC değeri ve Na + , Cl-, B ve Fe konsantrasyonu Yerüstü Su Kalitesi Yönetmeliği'ne göre çok kirlenmiş su (IV. sınıf) kalitesindedir. Kestanbol jeotermal alanında kabuklaşma problemi vardır. XRD ve SEM-EDX analizleri ile kabuğu oluşturan minerallerin kalsit, halit ve siderit olduğu tespit edilmiştir. Jeokimyasal analiz sonuçlarına göre kabuk, toprak ve dere sedimentindeki As, Fe ve Mn konsantrasyonunun Dünya kıtasal kabuk ortalama değerinden yüksek olduğu saptanmıştır. Zenginleşme faktörü ve jeobirikim indeksi değerlerine göre yoğun kayaç etkileşiminde kalan jeotermal akışkanın deşarjı sonucunda toprak ve dere sedimenti As ve Mn metal(loid)leri açısından zenginleşmiştir. Kestanbol jeotermal akışkanın ve tesisin atık suyunun çevresindeki toprağa ve Ilıca deresine deşarj edilmemesi önerilir.
Historical cemeteries are challenging targets for geophysical prospection but some non-destructive imaging techniques may be successful for mapping buried cemeteries if applied appropriately. Ground-Penetrating-Radar (GPR) has generally been considered to be the only geophysical method for determining cemeteries; however, Electrical-Resistivity-Tomography (ERT) and Magnetic-Imaging (MI), may determine geophysical traces of such cemeteries. Thus, as a first attempt at applying geophysical methods in the cemetery area of the Gallipoli Peninsula, these techniques were used to explore the buried graves at Agadere Cemetery. In this study, measured apparent resistivity data were processed using a two-dimensional (2D) tomographic inversion scheme. Resultant resistivity depth slices and volumetric resistivity images clearly showed the anomaly zone, which may be attributed to anthropogenic burials. Additionally, three-dimensional (3D) visualization of GPR results indicated some anomalies, much like the resistivity anomalies in terms of location. MI data were processed using linear transformations and an analytic signal image map presented anomaly zones located in some parts of the area, which are in agreement with those obtained by ERT and GPR surveys. Results derived from data processing techniques showed that these methods are suitable for bordering the locations of other buried historical graves in areas that have the same geological environment in the Peninsula.
In geodetic applications variety, one of the main current focuses is recently to determine the heights of ground stations with high accuracy. Specially the possibility of acquiring 3D information of the point positioning with high accuracy is opening up new strategies of investigating the heighting. Global Navigation Satellite System (GNSS) for 3D positioning is undergoing rapid developments and GNSS heighting can be an alternative to terrestrial techniques of height measurements. This paper presents a research study on the use of GNSS heighting in the case of steep slopes and multipath issue. Short baseline solution strategies were performed by using Bernese Software v. 5.0. The analysis results are also compared to the results of techniques of the terrestrial levelling. The results show that GNSS can be used as an practical surveying method to the terrestrial levelling with comparable accuracies. Furthermore, one can save up to 1 hour using GNSS instead of geometric levelling over a steep slope of a 100 m. On the other hand, as usual multipath is the primary error source decreasing the efficiency of GNSS, and it has been studied experimentally in this paper.
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