Cloud Creek crater

Cloud Creek crater is an impact crater in Wyoming, United States.[1] The crater is located in Natrona County, about 48 miles northwest of Casper, near the center of a geological feature known as the Casper Arch.[2]:445 The Cloud Creek structure is circular with a current diameter of about 7 km, and it is buried beneath about 1200 m of Mesozoic rocks.[2]:445 The age of the structure is estimated to be 190 ± 20 million years, which means that it formed as the result of an impact during the early part of the Jurassic Period.[2]:445 This impact feature is not exposed at the surface, but it is known only through wells drilled for oil and gas. First reported by Donald Stone,[3] Cloud Creek is a circular structure documented using several 2D reflection seismic lines of fair to good quality, gravity, magnetic and borehole data.[2] The structure has a central core of brecciated, fractured and faulted rocks uplifted up to 520 m relative to the normal stratigraphy outside the structure. The core is surrounded by an annular trough and a detached fault-bounded rim anticline. The rim anticline defines the 7 km diameter of the structure. The structure was compressed and upthrown during the Laramide compression. Morphometric parameters of the structure are consistent with known impact structures. The core is associated with a positive gravity anomaly. Magnetic data could not be interpreted.[2]

History

The first published report of the Cloud Creek Structure was in 1985.[4] However, an impact origin was probably first proposed sometime after 1973 by a Casper geologist named Jack Wroble[3]:233 A total of ten wells have been drilled for oil and gas within the boundaries of the Cloud Creek structure between 1955 and 1999.[3]:221–225 Two wells have been drilled with the central peak, four wells within the encircling skirt, and four through the outer rim structure.

References

  1. ↑ Cloud Creek on Earth Impact Database
  2. 1 2 3 4 5 Stone, Donald S. and Ann M. Therriault (2003). "Cloud Creek structure, central Wyoming, USA: Impact origin confirmed". Meteoritics & Planetary Science. 38 (3): 445–455. Bibcode:2003M&PS...38..445S. doi:10.1111/j.1945-5100.2003.tb00279.x.
  3. 1 2 3 Stone, Donald S. (1999). "Cloud Creek: A Possible Impact Structure on the Casper Arch, Wyoming". Mountain Geologist. 36 (4): 211–234. ISSN 0027-254X.
  4. ↑ Love, J.D.; A.C. Christiansen (1985). Geologic map of Wyoming. U.S. Geological Survey.

External links

Coordinates: 43°7′N 106°45′W / 43.117°N 106.750°W / 43.117; -106.750

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