Determination of coal layers using geophysical well-logging methods for correlation of the Gelik-Zonguldak and Kazpinar-Amasra (Bartin) coalfields, Turkey

Abstract

The most commonly used well-logging methods for determining coal layers are radioactive (gamma ray, neutron and gamma-gamma) and electrical (resistivity, spontaneous potential and inductive polarization). Other methods that can be used are sonic, thermal, density, caliper and dipmeter logs. In the determination of the coal beds, the evaluation of the well-logs and the interactions between the boreholes are very important. The boundaries of the geological strata are determined by the logs, which are also spatially correlated. The decrease in gamma-ray values, low neutron density, high resistivity, characterize coal layers. Due to the presence of large coal reserves in this area, 81 boreholes have been drilled at the determined points in the long term. Radioactive and electrical well-logs have been applied to these boreholes in order to determine lithology and coal beds. In this study, three boreholes from Gelik-Zonguldak region and four boreholes from Kazpinar-Amasra (Bartin) region were selected and evaluated. Geophysical data were used for the determination of coal beds and correlation. Regional assessments were made with the lithological, structural and tectonic data.