| Abstract: | Thermal experiments under laboratory conditions examined caliche discoloration and thermal conductivity/shock. the results provide information about caliche behavior under thermal conditions, which in some environmental settings will assist archaeologists in identifying discolored caliche from cultural activities as opposed to that from natural range fires. Generally, temperature intensity affects discoloration more than heat exposure duration. Sample colors change markedly towards darker values with carbon reduction between 300° and 700° C caliche glows during heating as the carbon oxidizes; the samples tend towards paler colors, lighter weight, and increased fissures. the thermal conductivity experiment compared heat transference of caliche with other lithic resources of the Llano Estacado, while the thermal shock measured caliche resilience. Metaquartzites and cherts from the Llano Estacado are better heat conductors than caliche, but caliche is far more resilient to repeated thermal shock. |
