The article considers geological information obtained during the study of cuttings and cavings which is becoming increasingly important. Together with the mudlogging data the well bottom hole is tied to reference and seismic horizons, a sludge diagram and a lithological section of the well are constructed, the porosity and saturation of promising formations are determined. Field petrophysical study of clay cuttings enable to estimate the compaction gradient of clay rocks with depth and calculate abnormally high formation pressures. The use of X-ray fluorescence and X-ray diffraction methods makes it possible to determine the chemical and mineral composition of rocks directly at the fieldwork. Attempts are being made to automate cuttings flowmeter and automated research (RoboLogger), cavings analysis. Studying the size of cuttings and cavings during drilling wells, especially with high deviation angles and at horizontal completion, when passing boreholes in such geological conditions as zones of abnormally high formation pressures and tectonic faults, as well as when using various drilling mud systems, can greatly help in identifying the condition of the well. Together with the mudlogging data and geophysical analysis, it is possible to quickly detect the initial stages of well bore instability and collapse, and take targeted preventive measures for borehole stability.
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