The electrical resistivity tomography method has been widely used in geophysics for many purposes such as determining geological structures, water movement, saltwater intrusion, and tectonic regime modeling. Karstic springs are important for water basin management since the karst systems are highly complex and vulnerable to exploitation and contamination. An accurate geophysical model of the subsurface is needed to reveal the spring structure. In this study, several karst springs in the Gökova Bay (SW, Turkey) were investigated to create a 3D subsurface model of the nearby karstic cavities utilizing electrical resistivity measurements. For this approach, 2D resistivity profiles were acquired and interpreted. Stratigraphically, colluvium, conglomerate, and dolomitic-limestone units were located in the field. The resistivity values of these formations were determined considering both the literature and field survey. Then, 2D profiles were interpolated to create a 3D resistivity model of the study area. Medium-large sized cavities were identified as well as their locations relative to the springs. The measured resistivities were also correlated with the corresponding geological units. The results were then used to construct a 3D model that aids to reveal the cavity geometry in the subsurface. Additionally, several faults are detected and their effect on the cavities is interpreted.
1 February 2019 in Environmental & Engineering Geoscience
En tr Turkey has many powerlines and various pipeline network due to its geopolitical position. Especially in recent years, many natural gas pipelines are projected and constructed in Turkey because of the rising need of energy supply in Europe. However, some problems which cannot be predicted during projecting stage can be occurred after the completion of construction stage and can jeopardize the safety of life and property. For this reason, rutin technical checking are crucial for the completed pipeline projects. In this study, a landslide occurred on a natural gas pipeline is investigated and engineering solutions are suggested. In this regard, field studies, office studies and laboratory studies are performed. Within the context of field studies, boreholes are drilled and test pits are excavated. Core samples obtained from the boreholes and soil samples handled from the test pits are subjected to laboratory tests. The results of laboratory tests are evaluated with the office studies and engineering approaches are fulfilled. With this study it is deduced that, the landsliding is triggered with excessive rainfall, the thickness of residual material is very shallow and it does not exist any risk of jeopardize the safety of life and property about the project. Türkiye jeopolitik konumundan dolayı birçok enerji nakil hatlarına ve değişik amaçlı boru hattı ağına sahiptir. Özellikle son yıllarda Avrupa’daki enerji arzı sebebiyle Türkiye’den geçen birçok doğalgaz boru hattı projelendirilmekte ve inşa edilmektedir. Ancak, projelendirme aşamasında öngörülemeyen bazı sorunlar inşa aşaması tamamlandıktan sonra ortaya çıkabilmekte, bazı durumlarda can ve mal güvenliğini tehlikeye sokabilmektedir. Bu nedenle, inşa aşaması tamamlanan boru hattı projelerinde rutin kontrollerin gerçekleştirilmesi büyük önem arz etmektedir. Bu çalışmada, bir doğalgaz boru hattı üzerinde meydana gelmiş olan bir heyelan incelenmiş ve mühendislik çözümleri önerilmiştir. Bu bağlamda, arazi çalışmaları, ofis çalışmaları ve laboratuvar çalışmaları gerçekleştirilmiştir. Arazi çalışmaları kapsamında, sondaj kuyuları ve araştırma çukurları açılmıştır. Sondaj kuyularından alınan sondaj karotları ve açılan araştırma çukurlarından alınan numuneler üzerinde gerçekleştirilen deneyler laboratuvar çalışmaları kapsamında gerçekleştirilmiştir. Bu çalışmalardan elde edilen sonuçlar, ofis çalışmaları ile değerlendirilmiş ve konuyla ilgili mühendislik yaklaşımları ortaya koyulmuştur. Bu bağlamda, boru hattı üzerinde meydana gelen heyelanın gelen aşırı yağışlarla tetiklendiği, heyelanın gerçekleştiği rezidüel malzeme kalınlığının çok az olduğu ve proje ile ilgili can ve mal güvenliğini tehlikeye düşürecek herhangi bir durumun bulunmadığı sonucuna varılmıştır.
1 January 2018 in Carpathian Journal of Earth and Environmental Sciences
Mustafa Can CANOĞLU, Bedri KURTULUS & Moumtaz RAZACK - SOIL–AQUIFER INTERACTIONS AND VADOSE ZONE MODELING: AN EXAMPLE FROM MARAIS POITEVIN (WESTERN FRANCE), Carpathian Journal of Earth and Environmental Sciences, February 2019, Vol. 14, No. 1, p. 171 - 180; DOI:10.26471/cjees/2019/014/069