Cloud Creek crater
| Cloud Creek crater | |
|---|---|
  Location of Cloud Creek crater in Wyoming  Cloud Creek crater (Wyoming) | |
| Impact crater/structure | |
| Confidence | Confirmed |
| Diameter | 7 km (4.3 mi) |
| Age | 190 ± 30 Ma Early or Middle Jurassic or Late Triassic |
| Exposed | No |
| Drilled | Yes |
| Location | |
| Location | Casper Arch |
| Coordinates | 43°7′N 106°45′W / 43.117°N 106.750°W |
| Country |  United States |
| State | Wyoming |
| Province | Natrona County |
Cloud Creek crater is an impact crater in Wyoming, United States.[1] The crater is located in Natrona County, about 48 miles (77 km) 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 kilometres (4.3 mi), and it is buried beneath about 1,200 metres (3,900 ft) 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
[edit]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
[edit]- ^ "Cloud Creek on Earth Impact Database". Archived from the original on 2012-06-05. Retrieved 2011-10-02.
- ^ a b c d e 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.
- ^ a b c Stone, Donald S. (1999). "Cloud Creek: A Possible Impact Structure on the Casper Arch, Wyoming". Mountain Geologist. 36 (4): 211–234. ISSN 0027-254X.
- ^ Love, J.D.; A.C. Christiansen (1985). Geologic map of Wyoming. U.S. Geological Survey.
