Congratulations to mulesinmo for the FTF!!!
Permission granted by the area manager, Thanks Mark!!!
The Crooked Creek impact structure is a 6-7km diameter or slightly larger complex crater located in southwestern Crawford County, Missouri, at approximately N 37° 50' by W 91°23' or (91.39485 degrees west, 37.83496 degrees north) (Mulvany, 2004). The crater is revealed on the Cook Station and Cherryville USGS 7.5 minute quadrangle maps. Important geological maps of the structure have been published by Hughes (1912), Hendriks (1954), and Mulvany (2004). The site is easily accessed. State Rte VV bisects the crater on the west side, with several smaller roads cross-cutting the area as well. The eastern side of the craters is disected from north to south by Crooked Creek, which exposes many areas of the bedrock affected by the impact.
The diameter of the site is generally listed as about 7 km based on the work of Hendricks, 1954, but may be close to 9 km based on GIS work by Nickerson, 2002 (unpublished MS thesis referenced by the more easily available Mulvany, 2004). Using the work of Norton, 2002, and the above estimate of diameter, Mulvany described a probably iron-nickel impactor with a diameter of about 250 meters and mass of about 65 billion kilograms.
The overall shape of the structure consists of a raised ring shaped central uplift (anticline) region about 2.5 km in diameter with a slightly depressed center. The central uplift region is composed of rebounded strata elevated in excess of 300 meters (1000 feet) (Hendriks, 1954) above their original position. Surrounding the upraised central basin and ring is a much larger depressed ring about 2 to 3 km in width that was left by both the impact excavation of material and by downward and inward flow of mass, in compensation for uplift, during crater modification. Beyond this depressed ring, Hendriks and other investigators report a resumption of the nearly horizontal bedding characteristic of the surrounding region.
Source: http://impactcraters.us/crooked_creek_missouri