The prominent hill on which Wadesboro sits is a part of the ancient Uwharrie Mountains that once extended from northern Georgia into northern Virginia. Montgomery County is somewhat considered the center of the Uwharries, although the 1,000-foot Morrow Mountain in Stanly County is the tallest remaining mountain in that chain. The Uwharries are considered among some of the oldest in the world, dating back to the Cambrian Era or around 500-million years. The mountains are volcanic in origin and could have been as tall, or taller, than the Rocky Mountains before their erosion slowly occurred over many millions of years.
Through Risden Hill and Steve Bailey of Wadesboro, I recently learned about the Lineham Brownstone Quarry that is located back of North Wadesboro Baptist Church between Highways 109 and old 52. Having studied geology and mineralogy and establishing somewhat science-related businesses, along with producing a documentary on the geological history of the Uwharries, I became extremely interested in this Wadesboro rock formation. Mr. Hill told me about several locations in Wadesboro where I could see specimens of this brownstone, including downtown near the D.A.R. Monument, under the foundation of his house and other locations. I also viewed a 20-inch square by 5-foot-long block of this brownstone at a home on East Morgan Street that was removed from that Lineham quarry. I eventually acquired a couple small specimens and began close examination along with making various tests and research.
The Peterson Rock and Mineral Field Guide states that brownstone is a sedimentary sandstone that occurs in many areas of the country and widely used in construction of foundations and stone walls. Over my career I handled many specimens of sandstone from areas all around the country and all have been light in color and consisted mostly of sand bound together with silicate or calcium. The Wadesboro brownstone consists of only a small portion of sand and originally mostly red mud.. Wadesboro is part of the Uwharrie Mountains and is an igneous (volcanic) formation and not a sedimentary formation. Because of these inconsistencies. I do not believe this brownstone should be classified as a sedimentary sandstone.
It is my opinion that the brownstone rock formation was created from a “mud volcano.” As an example, there are numerous mud volcanoes in Yellowstone National Park consisting of bubbling mud pots, as they are called, with mud flowing out and solidifying to form large mounds, etc. A mud volcano consists of superheated steam and gases coming up from deep within the earth that dissolve clays and some rocks while producing an outflow of accumulating bubbling mud and sometimes even a violent explosion of mud. On June 4, 2018, Guatemala’s Fuego Volcano had a gigantic explosion of mud. It coated trees with mud and engulfed houses and other buildings with rivers of brown mud killing more than 38 people.
The brownstone from Wadesboro has a red mud color from the presence of iron oxide. When broken apart, some surfaces show a botryoidal (lumpy) texture that occurred as it cooled and hardened. It has a surface hardness rating of around 6 on the Mohs Hardness Scale which indicates the mud was possibly, and eventually, bound together from dissolved silicates as occurred with most petrified wood.
It is also my opinion that the large Wadesboro deposit of extruded or exploded volcanic mud occurred during the early formation of the Uwarries, 400 to 500 million years ago, and was later covered with volcanic ash and lava perhaps to a height of a thousand feet or more. Over a period of these several hundred million years, the mountains eroded down to Wadesboro’s current elevation of around 512 feet above sea level, exposing the mudstone deposit that had solidified or, in a sense, “petrified” into the brownstone rock formation.
T.D. Burns lives in Matthews.