Bohrlochs

Bohrlochs are narrow shafts drilled into the ground to reach subsurface formations. They are used to extract fluids or gases, to sample rock and soil, or to monitor groundwater conditions. Boreholes can be temporary for testing or permanent as production or monitoring wells. In permanent installations, casings are inserted and cemented to prevent collapse and to isolate aquifers, while temporary boreholes may be backfilled after investigations.

Construction and components: Drilling rigs advance a drill string to create the borehole. Once established, casings are installed to maintain the borehole opening and to control fluid movement. The annulus between the borehole wall and the casing is often cemented to ensure well integrity. Depending on purpose, boreholes may include slotted or perforated casings or screens to allow controlled fluid flow or sampling. Downhole tools can measure pressure, temperature, and other properties, and can retrieve core samples or fluid specimens for analysis.

Types and applications: Water boreholes supply drinking water or irrigation and may serve rural or urban needs. Production boreholes extract oil, natural gas, or geothermal fluids. Exploration boreholes test rock properties and aquifer characteristics. Monitoring boreholes track groundwater levels, quality, and hydraulic conditions, supporting environmental protection, land-use planning, and resource management. Deep boreholes are also used in scientific research and energy storage technologies.

Drilling methods and safety: Common methods include rotary drilling with drilling mud or air, percussion or cable-tool techniques, and directional or horizontal drilling to reach specific intervals. Environmental and safety considerations emphasize well integrity, prevention of cross-contamination, responsible handling of drilling waste, and proper abandonment or decommissioning when a borehole is no longer in use.