Some places you just see things, and then there are a few special places where you experience an unsettling feeling about what you see.

A couple of months ago, I visited the Gettysburg Battlefield. There I stood at a stone wall and surveyed a beautiful pastoral scene spread before me, but I suddenly had a feeling of dread or foreboding. There was a horror there so thick you could cut it with a knife. The K-Pg boundary is such a place and when I first saw it nine days ago, I briefly had such a feeling again.

The K-Pg Boundary (Cretaceous-Paleogene Boundary, formerly known as the K-T Boundary) where it is exposed in northeast Mississippi, is visible as a thin brown layer sitting on top of Cretaceous Period chalk. What makes it so special is that it is physical evidence of the asteroid or meteor impact 66 million years ago offshore from the Yucatan Peninsula and the firestorm with a following tsunami that ripped across Mississippi and Alabama. That event and the nuclear winter that followed killed the dinosaurs and 75% of life on earth.

Ten days ago, George Phillips, curator of paleontology at the Mississippi Museum of Natural Science, called and said a team of researchers from across the country were examining an outcropping of the K-Pg boundary in Oktibbeha County. George thought I would find it interesting and should join them. So, I did.

The site was a beautiful Cretaceous chalk bottom creek with water rippling over fossil burrows once made by ghost shrimp. That was the day’s first lesson. I did not know that the burrowing ghost shrimp of the Cretaceous had survived the extinction event.

Down in the creek, two teams of researchers composed of faculty members and graduate students were at work. One was Dr. Cori Myers with graduate students from the University of New Mexico, and the other was Dr. Matt Garb from Brooklyn College with graduate students from Brooklyn College and the University of Southern California. They were examining the brown layer of sandy sediment which was created during the extinction event of 66 million years ago and is lying on top of the Cretaceous chalk of the Prairie Bluff formation.

When I speak of experiencing the site, just to look at that thin layer in the creek bank, realizing it is the actual evidence left by the event that wiped out the dinosaurs, created a sense of uneasy awe. It is almost frightening to think about that day and what occurred. The impact of the asteroid or meteor created a firestorm of molten material that was blown into the atmosphere and rained down thousands of miles from the impact site. Following the firestorm caused by the impact a tsunami between 300 and a 1,000 feet high swept into what is now north Mississippi and northwest Alabama. Evidence of the firestorm and tidal wave can be seen within the layer that is the K-Pg Boundary.

Research reported by the American Museum of Natural History showed that the base of the K-Pg Boundary in Oktibbeha County is composed of material ejected by impact into the atmosphere. These materials included impact spherules of molten debris and tektites. Reworked Cretaceous fossils are also found there. I even saw Cretaceous fossils of a small coral and a piece of Baculites, a straight-shelled ammonite reworked in the strata. A Baculites was an extinct animal related to today’s chambered nautilus.

Above the strata of ejected material was a brown muddy looking sand containing carbonized plant matter and what appeared to be charcoal or lignite. This sand may have represented a tsunami that rose to between 300 and a thousand feet high as it rushed north from the Gulf of Mexico. The study of K-Pg exposures between southwestern Tennessee and Scooba and the Livingston, Alabama, area show the sandy formation evidencing an increasingly violent deposition the further south you go.

The research going on last week and continuing this week is not the first on the K-Pg Boundary sites in Oktibbeha County. Dr. Renee Clary, professor of geology and director of the Dunn Seiler Museum at Mississippi State University stated, “My graduate student, Joshua Broussard (MS Geosciences, 2023) investigated the changes in paleodiversity across the K-Pg boundary in Oktibbeha County. Joshua collected fossils and used previously collected materials to compare the changes in organisms between the Cretaceous and Paleogene periods. He determined that after the K-Pg extinction, the remaining organisms were drastically smaller, and mostly consisted of suspension and deposit feeders, such as oysters and clams, and carnivorous gastropods.”

There have been other MSU graduate students who have encountered the K-Pg Boundary in their research, including current doctoral student Jonathan Leard, who cored through the boundary in his investigations. Some of the first investigations of the extinction event boundary in Mississippi were by George Phillips.

Thanks to Dr. Clary and George Phillips for helping me understand what I had seen and its significance.

Rufus Ward is a Columbus native a local historian. E-mail your questions about local history to Rufus at [email protected].