In order to construct the borehole extensometer at West Point, 1420 feet of 7 inch steel casing was fed into the ground using the drilling rig, as pictured here. This steel casing allows the borehole to hold its shape and not collapse in on itself, and isolates the 2 inch thick extensometer rod from the surrounding sediments.
Drilling for the West Point Borehole Extensometer
Detailed Description
Drilling a new borehole extensometer is a delicate task. The USGS Research Drilling Team worked with the researchers from Virginia Land Motion program to drill the 1420-foot-deep borehole for the extensometer at West Point.
Sources/Usage
Public Domain.
Related
The Virginia Extensometer Network
Borehole extensometers are instruments that monitor land subsidence caused by aquifer compaction. They provide precise, high-resolution measurements of changes in aquifer-system thickness. These changes in aquifer-system thickness contribute to vertical land motion (VLM) across the Virginia Coastal Plain, and are driven primarily by groundwater level decline due to human water usage. The Virginia...
Land Subsidence on the Virginia Coastal Plain
Land subsidence is a loss of ground elevation, often experienced as the ground slowly sinking over the course of years. In eastern Virginia, high rates of groundwater use is a major factor in the land subsidence affecting the area. The Virginia-West Virginia Water Science Center, with the help of our partners, has been monitoring land subsidence in the Virginia Coastal Plain since 1979 using a...
Drilling Rig Feeding Pipe into the Borehole for the West Point Extensometer
In order to construct the borehole extensometer at West Point, 1420 feet of 7 inch steel casing was fed into the ground using the drilling rig, as pictured here. This steel casing allows the borehole to hold its shape and not collapse in on itself, and isolates the 2 inch thick extensometer rod from the surrounding sediments.
Geologists Monitoring Sediment during West Point Extensometer Drilling
While drilling the 1420-foot-deep borehole for the West Point Extensometer, USGS geologists take the opportunity to learn all they can about the underlying geology. As they drill deeper, sediments are pumped out of the borehole. Geologists take samples of the sediments every 20 feet and note their composition.
While drilling the 1420-foot-deep borehole for the West Point Extensometer, USGS geologists take the opportunity to learn all they can about the underlying geology. As they drill deeper, sediments are pumped out of the borehole. Geologists take samples of the sediments every 20 feet and note their composition.
Related
The Virginia Extensometer Network
Borehole extensometers are instruments that monitor land subsidence caused by aquifer compaction. They provide precise, high-resolution measurements of changes in aquifer-system thickness. These changes in aquifer-system thickness contribute to vertical land motion (VLM) across the Virginia Coastal Plain, and are driven primarily by groundwater level decline due to human water usage. The Virginia...
Land Subsidence on the Virginia Coastal Plain
Land subsidence is a loss of ground elevation, often experienced as the ground slowly sinking over the course of years. In eastern Virginia, high rates of groundwater use is a major factor in the land subsidence affecting the area. The Virginia-West Virginia Water Science Center, with the help of our partners, has been monitoring land subsidence in the Virginia Coastal Plain since 1979 using a...
Drilling Rig Feeding Pipe into the Borehole for the West Point Extensometer
In order to construct the borehole extensometer at West Point, 1420 feet of 7 inch steel casing was fed into the ground using the drilling rig, as pictured here. This steel casing allows the borehole to hold its shape and not collapse in on itself, and isolates the 2 inch thick extensometer rod from the surrounding sediments.
In order to construct the borehole extensometer at West Point, 1420 feet of 7 inch steel casing was fed into the ground using the drilling rig, as pictured here. This steel casing allows the borehole to hold its shape and not collapse in on itself, and isolates the 2 inch thick extensometer rod from the surrounding sediments.
Geologists Monitoring Sediment during West Point Extensometer Drilling
While drilling the 1420-foot-deep borehole for the West Point Extensometer, USGS geologists take the opportunity to learn all they can about the underlying geology. As they drill deeper, sediments are pumped out of the borehole. Geologists take samples of the sediments every 20 feet and note their composition.
While drilling the 1420-foot-deep borehole for the West Point Extensometer, USGS geologists take the opportunity to learn all they can about the underlying geology. As they drill deeper, sediments are pumped out of the borehole. Geologists take samples of the sediments every 20 feet and note their composition.