Bohrlochlogbücher

Bohrlochlogbücher are systematic records kept for boreholes to document drilling activities, geological observations, and collected samples. They constitute primary data sources for geology, mining, and hydrogeology, and are used to interpret subsurface conditions, plan further work, and support engineering decisions.

Typical contents include: project details and location; borehole identifier; coordinates and depth; drilling method and casing; drilling fluids and operational parameters; lithological log with stratigraphic description; sample type and intervals; core photos or descriptions; geophysical logs (gamma, resistivity, density, sonic); groundwater measurements (static water level, yield); geotechnical tests (SPT, CPT, hammer tests); water and rock quality data; deviations, hole instabilities, boulder issues; notes on anomalies, repairs, and quality assurance.

Structure and standards vary by country and organization. Many logbooks are maintained in paper form or as part of digital borehole databases, and may be integrated with GIS and geological models. Data quality control, clear dating, and audit trails are emphasized, and standard terminology or coding schemes may be used to facilitate comparison across projects.

Bohrlochlogbücher support resource estimation, groundwater assessment, contamination delineation, and engineering design in mining, civil works, and environmental projects. They also provide historical records for re-analysis with new techniques, and serve as a reference for regulatory compliance and scientific research. In German-language contexts the term is Bohrlochlogbuch, with plural Bohrlochlogbücher.