TY - JOUR
T1 - Cation-ratio dating
T2 - A new rock varnish age-determination technique
AU - Dorn, Ronald I.
N1 - Funding Information:
This research was funded by the University of California and by National Science Foundation Grant SES 80-24555 to Dr. T. M. Oberlander. T. M. Oberlander called my attention to the Coso volcanic field and assisted in the collection of varnishes in the Coso region. I thank Julian Hayden for contributing samples for analysis, Ran Gerson for his help in selecting Israeli sampling sites, and Tom Dodson, Glen Roqmore, Carolyn Shepherd, and Dave Whitley for facilitating sam-
PY - 1983/7
Y1 - 1983/7
N2 - Rock varnish coats many surfaces of geomorphic and archaeologic interest in arid lands. All varnish dating techniques are limited by the time lag between the exposure of a surface to subaerial processes and the onset of varnishing. They are valid only where manganese is not remobilized after deposition, for example, in most arid environments. The premise of a new age-determination method, cation-ratio dating, is that the ratio of the more mobile cations (e.g., K and Ca) to titanium in varnish decreases with time. Although there are many inherent assumptions and potential limitations, cation-ratio dating has been verified on relative age-sequences from a Death Valley debris cone, Negev Desert talus flatirons, and prehistoric lake levels at Searles Lake in California. Varnish cation ratios have been calibrated to independently dated surfaces in the Coso volcanic field and vicinity in California. Tentative absolute dates have been assigned to geomorphic surfaces in the Coso area. Cation ratios have been used to distinguish relative ages of archaeologic artifacts in southwestern North America and to demonstrate that varnish at the South Stoddard locality, Mojave Desert, did not form in 25 yr.
AB - Rock varnish coats many surfaces of geomorphic and archaeologic interest in arid lands. All varnish dating techniques are limited by the time lag between the exposure of a surface to subaerial processes and the onset of varnishing. They are valid only where manganese is not remobilized after deposition, for example, in most arid environments. The premise of a new age-determination method, cation-ratio dating, is that the ratio of the more mobile cations (e.g., K and Ca) to titanium in varnish decreases with time. Although there are many inherent assumptions and potential limitations, cation-ratio dating has been verified on relative age-sequences from a Death Valley debris cone, Negev Desert talus flatirons, and prehistoric lake levels at Searles Lake in California. Varnish cation ratios have been calibrated to independently dated surfaces in the Coso volcanic field and vicinity in California. Tentative absolute dates have been assigned to geomorphic surfaces in the Coso area. Cation ratios have been used to distinguish relative ages of archaeologic artifacts in southwestern North America and to demonstrate that varnish at the South Stoddard locality, Mojave Desert, did not form in 25 yr.
UR - http://www.scopus.com/inward/record.url?scp=0021059508&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0021059508&partnerID=8YFLogxK
U2 - 10.1016/0033-5894(83)90065-0
DO - 10.1016/0033-5894(83)90065-0
M3 - Article
AN - SCOPUS:0021059508
SN - 0033-5894
VL - 20
SP - 49
EP - 73
JO - Quaternary Research
JF - Quaternary Research
IS - 1
ER -