My friend Scott sent me an AP article on a mysterious crater outside of Merna, NE. So one weekend, he and I packed up for a weekend trip from Des Moines, IA to this mysterious geological phenomenon. Hooked up with my father to ponder some theories as to the "hole's" creation as well as place a cache so others may find this odd little feature in the Nebraska Sand Hills.
The following is excerpted from an Associated Press article published in the 20 July 2002 edition of the North Platte Telegraph
MERNA, NE (AP) - Professor Wakefield Dort Jr. passionately tells anyone willing to listen that the mile-wide dent near this farm village was created when a meteorite slammed into the Earth as recently as 500 years ago . . . some folks back in Nebraska say his theory is out of this world - full of holes, if you will. In the middle of the debate is 82-year-old Frank Bartak, who was born in a homestead on the edge of the contentious depression and whose family still farms the land in and around it some 10 miles west of Merna. . . The depression - or crater - does look out of place. The Bartaks grow crops in it, but even that doesn't help it blend in much. Rolling fields of corn, soybeans, alfalfa and pasture stretch for miles in all directions up to the depression's edge, which drops 65 feet at some points to the floor below.
Dort believes the depression was formed by the impact of a large meteorite that packed an explosion with the force of several hydrogen bombs between 3,000 and 500 years ago. Dort started studying the site in 1991 after he and some colleagues discovered the unusual dent on a topographic map - a nearly perfectly round formation smack dab in the middle of Nebraska. Dort has collected samples from the site and claims he found thousands of minute black magnetic particles not native to Nebraska. He also notes that Pawnee Indian legend tells of a "thundering cloud" that appeared over the area "leaving behind children of black stone." Dort's team also found a layer of crushed glass about three feet below the surface with a pocket of gray soil underneath. University of Nebraska geologist Vern Souders speculates that what Dort found is fulgurite, which is formed when lightning strikes sand. The Nebraskans said they found the "crater" had the same origin as similar, though less impressive, depressions in the region carved out by relentless winds during dry periods thousands of years ago.
The original small sample jar cache contained a $1 bill, small pen (someone will need to add a logbook), and a wheel holder for a RadioFlyer wagon.
The Chemist-Geologist-Civil-Engineer-Team's Humble Opinion: Being able to only view surface topology, we opine that the Nebraskian's theory is weak because, to the best of our knowledge, there are no neighboring "craters" in the Sand Hill region to suggest that the Merna Crater is a non-unique feature to the region, nor are there any modern homologous eolian structures in the dune fields of the world. It may be true that about 5% of the stabilized dunes in the Sand Hill area are parabolic in shape, but these have a consistent southeastern orientation and are confined to the southwestern part of the Sand Hills. The Merna Crater is circular in shape with no apparent orientation. Furthermore, the Merna Crater seem out of place situated on West Table, which appears to be a moderate-relief sand sheet - a geomorphic feature of sand seas where the average maximum relief in a quarter section ranges from 30 to 70 feet with slopes up to 20 percent. (An Atlas of the Sand Hills)
POST YOUR THEORY!!!!
This area has drawn the attention of some Google Earth user groups that propose that the Merna Crater, and some similar features in Nebraska, are western counterparts of the enigmatic Carolina Bays and Godsboro Ridge; created by ejecta from a postulated shallow angle-of-incidence comet impacting the ice shield over Michigan 140,000 years ago, thereby creating Sanginaw Bay.
Update: Now a coffee container. Thank you geocachers for your help in maintaining this unique geocache.