Mint Canyon Formation
The Mint Canyon Formation (Tm) is a Miocene geologic formation in the Sierra Pelona Mountains of Los Angeles County, southern California. The formation preserves fossils dating back to the Middle to Late Miocene (Barstovian and Clarendonian in NALMA classification). Geology. Mint Canyon is a fluvial landform in the Sierra Pelona range. It consists of terrestrial deposits from streams and lakes consisting mostly of sandstone and conglomerate with some claystone. The formation correlates with the Caliente Formation in the Plush Ranch Basin to the northwest and the lower Punchbowl Formation in the Punchbowl Block to the southeast. The  Mint Canyon Formation consists primarily of fluvial, alluvial, and lacustrine conglomerates, sandstones, and mudstones. The Mint Canyon Formation is overlain by the dominantly marine Castaic Formation, which consists of shale, sandstone, and minor conglomerate. In the Texas Canyon sub-basin, the formation is overlain by the Saugus Formation. The contact between the Mint Canyon and Castaic Formations is an angular unconformity in some places, and it is apparently conformable and gradational in others. Fossil content. The formation preserves vertebrate fossils dating back to the Middle Miocene subperiod of the Neogene period: