Paleozoic Impact Crater Field

Date: June 27 - 28, 2020
Location:  Show map
Douglas, Wyoming
Douglas, WY 82633
Register Here: 


Tickets not currently available for this event

Trip postponed until 2021

On this unique field trip the participant will see more impact craters in one day than anywhere else on Earth. Only by visiting the Moon or another planetary body could you see more. The Douglas Impact Site was named and formally described in this free online scientific report written by trip leader Kent Sundell and published by Nature last year. 

The Douglas Impact occurred at the Pennsylvanian/Permian boundary at the contact between the Casper Formation and the overlying Goose Egg Formation redbeds about 280 Ma. This is the same contact as the Minnelusa/Opeche contact in the northern Powder River Basin. More than 130 possible craters have already been observed using Google Earth, drone flights, and field observations. About 15 of these impact features have been confirmed by thin section analysis to contain shocked quartz, verifying their origin. Some of the 130 possible craters will probably not be confirmed, but many more are expected to be found. Come see the crater rims, vertical and overturned margins, ring fractures, impact breccias, shock metamorphosed quartzite, radial fractures with impact breccia filled veins. An astrogeologist’s dream come true. Stand where Harrison (Jack) Schmidt (the last man and only geologist to walk on the Moon) has stood before. Discuss and argue the many hypotheses pertaining to this recently recognized ancient impact surface on Earth. Discuss ongoing research by Casper College faculty and students using drones, field mapping, geophysics, geochemistry, and hopefully future drilling to elucidate this newly recognized natural wonder of the world.

This trip should interest any geoscientist curious about the effects of extraterrestrial impacts on planet earth, anyone that is currently working on or has previously worked on the Minnelusa oil play in the Powder River Basin (is the relief at the Minnelusa/Opeche contact really preserved sand dune topography?), and anyone pursuing potential causes of late Paleozoic climate changes.

Please note: This trip requires strenuous hiking up steep rocky slopes. Please bring and use walking sticks, sturdy hiking boots, sun screen, a hat, 2-3 quarts of fluid, and sun glasses. Rock hammers are optional. Rattlesnakes, scorpions, cactus, poison oak, and barbed wire fences are a few of the hazards we may encounter (still easier than going to the Moon and a whole lot cheaper).

Logistics Summary: The group will assemble at 7:30 pm on Saturday evening, June 27th in the conference room at the Douglas WY Hampton Inn for an introductory discussion, meet and greet, and logistics discussion (including carpool arrangements discussion). Participants will meet at 7:45 am on Sunday, June 28th in the parking lot of the Subway/Conoco at 1115 W Yellowstone Hwy, Douglas, where anyone needing additional lunch, drink, or fuel supplies can top up. We will plan to leave this parking lot at 8:15am, following Dr. Sundell (trip leader). Much of the road to the outcrops will be dirt/gravel, so although 4x4 vehicles are not required they are recommended (especially if it has been wet/rainy). The group will park in a flat field, where Dr. Sundell will provide instructions for the day. From there, the group will follow Dr. Sundell on a hike across steep terrain to visit multiple impact craters. Participants are responsible for bringing their own lunches, which will be eaten on the hike away from the vehicles. The trip will end at or about 3:00 pm, depending on weather conditions and participant enthusiasm.

Download details and logistics

Download waiver


Great Western