Paleontological resource inventory and monitoring—South Florida / Caribbean Network

Toscano, Marguerite; Kenworthy, Jason; Santucci, Vincent

Paleontological resources (fossils) are any remains of past life preserved in a geologic context. Paleontological resources are non-renewable resources found in more than 224 National Park Service units. Despite the abundance and diversity of these resources throughout the NPS, until recently few parks have adequate baseline paleontological resource data. The NPS National Inventory and Monitoring Program and the NPS Geologic Resources Division have developed various strategies to provide parks with the baseline paleontological resource data necessary for greater understanding and appropriate management of these resources. This report presents a paleontological resource summary for the parks of the South Florida / Caribbean Network. The summary was compiled through extensive literature reviews and interviews with park staff and professional geologists and paleontologists. Preliminary paleontological resource management recommendations are also included for each park. In general, the paleontological resources known from the parks of the South Florida / Caribbean Network (SFCN) come from the late Cenozoic Era, particularly the late Neogene through Quaternary periods. All SFCN parks have fossils typical of marine carbonate environments, including fossil coral reefs, skeletal carbonate shelf sediments and other fossiliferous coastal deposits. Big Cypress National Park (BICY) and Everglades National Park (EVER) share similar modern wetland environments as well as their underlying carbonate geology. Both are underlain by a vast shallow marine bryozoan facies deposited during the peak of the last interglacial period (~125,000 years ago) when sea level was 6 meters above present levels. BICY has manmade exposures of a deeper Neogene marine fauna; EVER’s fossil resources extend to Holocene Florida Bay sediments. Dry Tortugas National Park (DRTO) has late Quaternary fossils associated with cultural resources (Civil War fortifications, shipwrecks, and an early 20th century science laboratory). Biscayne National Park (BISC) shares the same Pleistocene fossil reef formation underlying DRTO, but, like all of the middle and upper Florida Keys, has this fossil reef exposed as the surface rock. The late Quaternary fossil corals of BISC and DRTO have been used to document glacial-interglacial sea-level cycles, paleoclimate and comparative mid-late Pleistocene and Holocene coral reef ecology, species changes, and geologic history along the northernmost western Atlantic coral reef system. Both parks presently encompass large subtropical shallow marine areas with ongoing production of skeletal deposits including coral reefs, subsequent taphonomy, and fossilization. The parks of the Virgin Islands, consisting of Buck Island Reef National Monument (BUIS), Salt River Bay National Historical Park and Ecological Preserve (SARI), and Virgin Islands National Park (VIIS), contain recent marine carbonate deposits similar to those of BISC and DRTO, including coral reefs and biogenic shelf sediments. On St. John Island (VIIS) these deposits rest on virtually non-fossiliferous deformed and intruded pre-Cretaceous volcanic rocks. On St. Croix, late Quaternary marine deposits occur on a base of meta-sedimentary and deformed marine formations, in particular the Cretaceous Caledonia Formation. Thus most of the fossil material is of geologically recent age, ranging over the past 130,000 years of geologic time.

Paleontological resource inventory and monitoring—South Florida / Caribbean Network

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