Sloan Canyon National Conservation Area, located on the southern edge of the Las Vegas Valley, encompasses more than 48,000 acres of unique geological features including at least five volcanic domes. The highlight of this conservation area, which was granted its federal designation in 2002,
is the North McCullough Wilderness. This protected wilderness contains an extraordinary number of ancient petroglyphs fashioned by native cultures, which date back to the Archaic period (8000 BC–1000 BC). Most of the rock art panels occur in a small area in Sloan Canyon, creating an impressive open-air rock art museum. With more than 300 panels and 1,700 individual design elements, some have called it the Sistine Chapel of Native American rock art.
It is reported that clearly identifiable representational elements, such as bighorn sheep and human figures, constitute only 11% of the various motifs. Surprisingly the majority are abstract markings with open forms. Although these marks may have had specific cultural meaning to the ancients, their purpose and meaning elude us today. The majority of petroglyphs are created by scratching off a micro layer of rock varnish (also called Rock dust and desert patina) revealing the lighter rock beneath.
The formation of rock varnish seems to be as mysterious as the petroglyphs themselves. What is known is that varnish forms on stable surfaces that are protected from excessive precipitation or wind abrasion. The varnish is composed of clay, iron, magnesium oxides and traces of organic material.
There is so much that is unclear regarding these fascinating abstract markings. What is clear to me is the human need to make our marks on nature and share our experiences and thoughts with others. Occasionally, I ponder why I am compelled to keep a visual journal — a process and discipline I have maintained for more than two decades. There is something about seeing these ancient markings that reassured me that my urge to make abstract marks on paper is the continuation of an ancient tradition and a manifestation of a real human need.