Rockwall recently enjoyed a moment in the spotlight as geologists marveled at the town’s namesake. The actual rock wall once discovered by the founders of the city was excavated by local father-son duo Kevin and Daniel Richeson for an episode of the History Channel series “America Unearthed,” scheduled to air in November.
Scott Wolter, the host of America Unearthed, said that the History Channel found out about the town phenomenon from a tip line affiliated with the show.
“Adam Nix from the Collin County Historical Foundation contacted the History Channel about a month and a half ago,” Rockwall High School senior Daniel Richeson said.
Nix then called the Richesons and asked if they wanted to excavate the rock wall for the show.
Kevin Richeson originally excavated the wall for the first time in 2000. The process took 18 months and then an additional 11 months to refill the land. Since the wall is located on private property, each time it undergoes excavation it must be covered all over again.
Due to significant improvements in machinery, the most recent excavation took just one week and refilling the land only one day.
“We have three pieces of machinery Hyundai is giving us to use: two monster track hoes and a reticulating loader,” Daniel said. “It’s fun pulling all the dirt out, but not putting it back in.”
Daniel estimated that this time around the team uncovered a section of the wall 100 feet long and 30-35 feet deep.
The founders of the town originally found an exposed area of the wall near what is now Highway 66.
“They found parts of the wall all throughout Rockwall County, and that is how it [the county] ended up as a square,” Daniel said. “Farmers would put their wells next to the wall because it would create a natural aquifer.”
But the wall’s fascinating history doesn’t end there. Part of the incentive to uncover the wall, even temporarily, is to determine its age. Depending on what geologist John Giessman discovers, there could be massive historical implications to the wall’s origins.
The wall could be an ancient limestone dike, a natural feature several million years old and the only landmark of its kind in the United States. The wall is possibly a manmade structure as indicated by the individual pieces of brick in some areas. Evidence might also indicate that the wall is a combination of both.
“Regardless of what it is, it is an amazing, weird, cool thing,” Wolter said. “I can see why people really got excited about it. I’ve never seen anything like it.”
The process used to calculate the age of the wall involves complicated measurements of the paleomagnetism within samples of the rocks.
“The geologist takes the core samples we cut out and makes sure we have their proper orientation in the wall, because essentially the plaeomagnetism gets locked into the rock at the time it formed,” Wolter said. “The magnetism direction changes over time, and it will flip-flop. We are measuring where the arrow is pointed for this moment in time.”
Daniel said that over thousands of years the true magnetic north pivots on the axis. Geologists then compare the alignment of the crystals to a timeline to date them.
“The theory is, if this is a natural feature then all the arrows should be pointing in the same direction because the rock was all made at the same time,” Wolter said. “If it’s a man-made feature, as they put the blocks in they would be rotated and they would not line up, so the arrows should be random going in all directions.”
The results of Giessman’s analysis won’t be available to the public until the airing of the show at the end of this year.
For Kevin and Daniel Richeson, the wall’s excavation is significant regardless of the findings. Kevin Richeson has been in the excavating business for 35 years, and Daniel plans to follow in his father’s footsteps after graduation.
“I really enjoyed digging the rock wall out,” Daniel said. “It was a great experience to share with my dad.”