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Pictures of core and cuttings

Various Resources Provided by the CRC


Core Research Center -- Available Resources

In 1974 the U.S. Geological Survey (USGS), in cooperation with the Rocky Mountain Association of geologists, established a permanent free-access core repository in Denver. The purpose of the repository is to rescue rock cores threatened with destruction or disposal, process and store them in an efficient manner, and make them available for observation and sampling by all interested parties. The collection contains full-diameter cores, slabbed cores, and well cuttings.

The Center is one of the largest public core repositories in the country and has cultivated a high degree of trust and integrity with its donors and users. Conservative estimates, based on the value of cores housed at this facility, indicate that the public cost of storage per year is only about 0.5 percent of the original cost of drilling, and 0.05 percent of what it would cost to drill the cores today. The USGS can store the cores, which are used for educational and research purposes, for at least 200 years before reaching the original cost of drilling.

The USGS maintains the most diverse public-access core collections in the country.

A variety of core sub-collections are available in the repository, including those from oil shale development; Eniwetok Atoll; Cajon Pass, California; Yellowstone Park; and off-shore wells. In addition CRC curates one of the country's larger collections of cuttings (rock chips) brought to the surface during drilling operations, which are invaluable for constructing geologic concepts of an area. The core and cuttings collection is also accompanied by a large collection of thin sections, which are used to examine microscopic details of the rocks. Images of the thin sections and photographs of some cores are available for viewing and download. Files containing chemical and physical analyses, core descriptions, stratigraphic charts, and various other analyses performed by previous users of the collection can also be downloaded. Click on the library number in the Well Catalog lists to find links to the image and report files.

The USGS curates one of the country's larger collections of drillhole material.

The CRC houses about 2 million feet of core in the general collection of petroleum exploration and development holes as well as in specialized collections. These cores come from 33 states and about 95 percent were donated by petroleum and mining companies, State geological surveys, other Federal agencies, and universities; about 5 percent are special scientific cores drilled by the USGS. In addition, the CRC maintains over 25,000 thin sections taken from cataloged cores and cuttings. Cuttings from over 52,000 wells in 27 States are also housed at the repository. This unique collection of cuttings represents around 240 million feet of drilling at a replacement cost of over $80 billion.