- Last Updated on 07:41 AM 12/14/12
- BY Special to the Gazette
The Dan River Basin Association’s First Saturday Outing on Jan. 5 will be a two-mile hike on a farm in Ruffin, N.C., to explore Tanyard Creek. Meeting at 10 a.m. at Happy Home School, participants in the outing will carpool to the site.
Trip coordinator Milton Hundley, an amateur naturalist, geologist and raconteur, said, “Tanyard Creek has a three-stage waterfall over 20 feet high.”
At this time of year, the waterfall is unspectacular, as the stream will likely be only a trickle.
The main reason for the hike is not the water, however, but the unusual streambed and surrounding geology.
Named for the tannery owned by the family of 19th-century Governor John Motley Morehead (1796-1866), Tanyard Creek creates a gorge as it cuts through Triassic rock on its way to the nearby Dan River. The “puddingstone” conglomerate formation and petrified wood in the streambed have earned the area’s listing as a North Carolina Natural Heritage site.
In the Triassic Era, some 200 million years ago, this section of northern North Carolina and southern Virginia was a deep lake. As rivers flowed into the lake, the slowing water dropped its load of sediment-first the large rocks, then smaller pebbles, then sand and silt. Over the eons, geologic pressures fused the surrounding clay particles, enclosing the rounded rocks and pebbles in an aggregated mass.
These same geologic forces caused some buried logs to become petrified as minerals replaced the organic matter while retaining the original structure of the wood. Small chunks of petrified wood can be found along Tanyard Creek.
Hundley said, “The waterfall goes across the puddingstone, which looks just like concrete. A bowl-shaped rock that was believed to be a grinding mortar is eight or nine feet up the bank, perhaps used for crushing hickory nuts or acorns.”
Lines of dark gray rounded boulders, known as igneous dikes, stretch through the woodland along the path to the creek. These dikes were formed when molten rock was forced through underground fissures where it cooled slowly into dense, fine-grained stone that was exposed when the surrounding material eroded away.
Paddlers on the Dan River may see igneous dikes and conglomerate formations in the river at such places as Wide Mouth and Tanyard shoals. Both of these shoals are traversed by navigation sluices constructed in the 19th century to enable commercial batteaux-long, narrow, flat-bottomed wooden boats-to pass safely through the rapids.
Participants in the outing should bring water and lunch, wear hiking boots and layers of water-shedding artificial fabric or wool, and be prepared for rain or wind. Because of the uneven surfaces in the streambed and a short steep ascent out of the gorge, hiking poles are advisable. All participants will be asked to sign a waiver form.