Caliche in Southeastern New Mexico

Caliches with similar zonal profiles lie on the Pliocene Ogallala formation of the Llano Estacado and on three younger surfaces along the Pecos depression. Physiographic relations, the caliche profile, and other features indicate that the caliches were developed by soil-forming processes from parent-materials consisting largely of limestone gravels. The caliches and associated solution features provide a partial record of climatic changes since middle Pliocene time.