Abstract This field guide was originally put together for the SEPM Research Conference on Permo-Carboniferous Carbonate Platforms and Reefs in 2000 (SEPM SP 78 contains the research papers from the conference) and was only distributed to those attending the conference. After receiving copyright permissions, it has become an official publication of SEPM - Field Guide No. 12 and is available on CD. This guide begins in the Dry Canyon area of the Sacramento Mts. devoted to platform evolution during Missourian and Virgilian times, focusing on mounds and cycles of the Holder Fm. Also covered is the Mississippian Lake Valley Formation's sedimentology and depositional environments in Indian Wells Canyon and Alamo Canyon again with focus on mound biota and comparative sedimentology of mound versus level-bottom biota. Muleshoe Mound in the southern part of the Sacramento Mts. is used to examine mound growth history and an example of differential compaction and modern day appearance of outcrops. This volume includes background geology on all of the areas that are visited as well as detailed discussions about each of the field trip stops.