Carbon dating the borax lake site
Characteristics suggested for San Dieguito Complex assemblages, in addition to the abundant scrapers, have included large, percussion-flaked bifaces; flaked crescentic stones; Lake Mohave or Silver Lake style projectile points; a scarcity or absence of milling tools (manos and metates); and an absence of small projectile points and pottery.
Rogers recognized three distinct chronological phases for the San Dieguito Complex, based primarily on changes in lithic technology, site locations, and site types.
To date, I have located six sites consisting of one or more rubbing rocks, all within an area about 4 km in diameter.
The two main sites are referred to as Mammoth Rocks and Jasper Rock.
This Preserve holds one of the oldest sites in California, dating to 12,000 years ago.
The site was first discovered in 1938 by amateur archaeologist Chester Post.
Harrington recognized the fluted points as similar to ones found in association with extinct Pleistocene mammals in the southwest, and eagerly began research at the site that lasted from 1938 to 1946.
Harrington uncovered fluted points, chipped stone crescents, widestem points, millingslabs, manos, pestles, mortars, and other associated artifacts. Clement Meighan performed obsidian hydration on Harrington’s artifacts.
In the latter, early Holocene remains are more generally assigned to the Borax Lake Complex and Post Pattern.His changing terminology for these phases (including the equation of "Malpais" and "San Dieguito I") have caused some confusion in the archaeological literature (Rogers 1939).Most researchers do not now use these subdivisions.Interpretations of the San Dieguito Complex have varied.Some have seen its makers as big game hunters, perhaps in succession to the late Pleistocene-era Clovis culture, while others have seen them as generalized foragers.