Cutting analyses and application of their results

Abstract

An overview on cutting sampling and analyses is illustrated by a case study. It shows the results of cutting analyses: Rock-Eval data, hydrocarbon gas contents and carbon isotope ratios from cutting gases, biomarker and carbon isotope ratio data of the cutting extracts. The presence, thickness and kerogen types of source rocks were established by Rock-Eval data. Carbon isotope ratios of hydrocarbons in cutting gases indicated kerogen types II/III and III, moreover the presence of bacterial methane in addition to thermogenic one. Carbon isotope ratios of etane and propane in DST gases show an autochthonous character. Based on biomarkers and carbon isotope ratios of the cutting extracts, it can be established that Pannonian and Middle Miocene extracts are genetically different, moreover hydrocarbon fluid from DST was generated by Middle Miocene source rock, and has an autochthonous character.