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Coso Rock Art | archeology / surveying sites / dating rock art
archeology Surveying sites

One thing that makes the Coso archeological complex special is that it is exceptionally well-preserved. This is partly due to the remoteness of the place and the dry, stable climate, but it is also the result of the U.S. Navy's efforts to meet its obligations as a federal land management agency.

All federal land-holding agencies are charged with protecting the cultural resources under their care. As the protector of a National Historic Landmark, the Navy faces the additional requirement that they not allow their normal functions to affect the Coso petroglyphs in an adverse way. Archeological discovery and analysis allows the Navy to know just where the petroglyphs are and, consequently, how to plan their exercises around them.

Since the early 1960s, archeologists have studied Coso with the aim of determining the District's borders. One three-season survey in the late 1960s was thorough enough to identify the essential range of petroglyph concentrations, resulting in preliminary borders for the District.

Archeologists walked along the bases of the volcanic terraces or down through the canyons, locating and recording rock art. They also found numerous intact village, camp, and work sites, each containing important information about the lives and beliefs of the ancient Numic people.

Further surveys fleshed out the variety of petroglyph types, styles, and locations. Likewise, newly-discovered work and occupation sites provided fresh insights into how Coso culture changed—and remained stable—over time. more >>


(photo) Smooth basaltic stone with anthropomorph image.  By TOMOL.


Archeologists have found that Coso's petroglyphs and occupation sites are located almost exclusively in the volcanic basalt of the Coso Mountains, rather than in the surrounding granitic landscape. But why? According to Bob Higgins, NPS Chief Geologist:

Basaltic and granitic rocks look very different and presented clearly distinct surfaces to prehistoric artists. The basaltic rocks are dark in color (black and dark brown) and appear fine grained with a tough surface. Granite is generally lighter in color, appearing gray or pinkish tan and has a coarser textured surface.

Granite and basalt age or weather differently as well. Granite tends to disintegrate over time by breaking apart into small pebbles or large boulders while basalt tends to wear away smoothly. Perhaps ancient artisans were aware of this tendency and therefore chose to leave their marks in places where they would remain the longest.

Some have theorized that creators of rock art around the world prefer to use rocks that produce a sharp contrast in color when chipped. Basalt, unlike granite, has a desert patina that provides striking contrast when scratched.

All of these ideas about the influence of rock characteristics are conjectural and yet could have influenced the choice of canvas for Coso rock art. An alternate and probable reason for the majority of images being on basalt is simply that much more basalt is exposed at the surface. Perhaps ancient artisans chose to work with the material that was most readily available.

(photo) Archeologist with clipboard standing in a  hunting blind.  Far Western Anthropological Research Group, Inc.


Most of Coso's petroglyphs are found near hunting sites. Here, an archeologist works inside a hunting blind, a small, ring-shaped stone wall big enough for a bowman to squat in as he waited for game to be driven by. Coso hunters and their dogs flushed large game such as bighorn sheep towards canyons or other narrow places where bowmen waited in ambush.

Another prominent hunting feature also played a part in the ambush: stone cairns built along the top of a ridge looked to panicked bighorns like a line of humans. These so-called "dummy hunters" helped channel quarry away from the heights, where the steep terrain slowed men and dogs, but allowed the sure-footed sheep to escape.

(photo) Ring of basalt blocks on cracked mud floor.  Far Western Anthropological Research Group, Inc.


Stone rings mark the remains of stick-and-tule houses. These homes were built with large branches as a framework for a covering of reed mats or brush. Rocks secured the base of the house.

This ring sits on a playa floor, a place where brackish water occasionally pooled. Any remaining runoff channels would have provided access to much-needed seasonal water sources for people-and for animals. A village site like this one may have been chosen for its water, the useful plants that would grow nearby, and the birds and mammals that would come to drink.

(photo) Round pile of stones in a grassy uplands field.  Far Western Anthropological Research Group, Inc.


Rock-filled stone rings are believed to be collapsed pinyon-pine cone caches. Usually located near upland villages, pinyon caches stored mounds of ripening cones for later processing.

Archeologists consider pinyon caches evidence for the development of a foraging style marked by the intensive use of nearly every available food source. For example, while other people may have gathered ripened pinyon nuts that had fallen to the ground, Coso's Numics extended their reach by using long hooks to pull greener cones from the tops of trees.

They also turned the pinyon nut harvest into a festival, with whole villages gathering at upland sites. Everyone participated in the activities, including kids, who climbed the lower limbs and picked cones while adults hooked those up top. In ways like these Numic gathering methods were more thorough, albeit more labor intensive.

(photo) Large concave stone slab with two round grinding stones.  Far Western Anthropological Research Group, Inc.


Coso's people used stone manos and metates to grind hard seeds or to pound fibrous roots into flour. Though foods such as small, hard seeds required more work to gather and process, they also allowed for larger populations, less travel, and more secure provision. Some archeologists believe this gave Numic peoples an advantage over other hunters and gatherers, and even over agriculturalists, as they moved into the Great Basin.