Stable oxygen and carbon isotopes of pedogenic carbonate as indicators of plio-pleistocene paleoclimate in the southern Rio Grande rift, south-central New Mexico

Three different paleoclimate stages are exhibited by the study of stable carbon and oxygen isotopes of pedogenic carbonate of Camp Rice Formation. The first stage has a low-level of C-13 and O-18 isotopes. During this stage, the isotopic values increase with a reduction in age. During the second stage, there is an increase in the oxygen isotope concentration with reduction in age. There is an overall increase in both oxygen and carbon content in the last stage.