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Resources & Services


Available Services

The CRC encourages use of its extensive collections by all interested parties at its well-maintained facility in Building 810, on the Denver Federal Center. A well-lit and spacious core examination room is available to users of the core collection. Binocular microscopes, water spray bottles, and 10% hydrochloric acid are provided. A photo stand and floodlights are available for use by visitors who bring their own cameras to photograph sections of core.

A separate cuttings examination room, equipped with microscopes, oil fluoroscopes, and a new sample dryer, is available to users of the large cuttings collection. For viewing and photographing thin sections, the CRC has two petrographic microscopes with computers and digital cameras. Users are allowed to bring a thumb drive to save their photomicrographs. The CRC has over 25,000 thin sections derived from the cores and cuttings in the CRC collections.

Adjacent to the examination rooms, the CRC has a small conference room and a large lecture room. In conjunction with a core or cuttings viewing appointment, researchers may reserve one or both of these rooms for showing presentations to colleagues or for conducting core workshops. Ten people can be seated around the large table in the conference room. The lecture room holds 45 people when set up like a classroom or 90 when arranged auditorium-style. When not occupied by users of the CRC collections, these rooms are exclusively reserved for use by USGS or other Federal agencies for official business meetings.

The CRC receives up to 2000 visits each year from researchers representing Federal and State agencies, industry, and educational institutions in the U.S. and abroad. For the past 40 years the geologic community has benefitted from the invaluable collections maintained at the CRC.

The Core Research Center is located at the southwest side of Building 810, on the Denver Federal Center. Viewing of cores or cuttings is by appointment only. The CRC is open to the public Monday-Friday, 8:00 a.m. - 3:00 p.m. To obtain more information or to schedule a visit to the CRC, please email or call 303-202-4851.

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.