The Inception of the Colorado Plateau Coring Project: Filling the Triassic Geochronologic Gap and Providing a Continuous Record of Continental Environmental Change in Western Equatorial Pangea

Tuesday, 16 December 2014
John W Geissman1, Paul E Olsen2, Dennis V Kent2,3, Randall B Irmis4, George E Gehrels5, Roland Mundil6, William Parker7, Gerhard H Bachmann8, Wolfram M Kurschner9 and Jingeng Sha10, (1)University of Texas at Dallas, Dallas, TX, United States, (2)Lamont -Doherty Earth Observatory, Palisades, NY, United States, (3)Rutgers University New Brunswick, EPS, New Brunswick, NJ, United States, (4)Natural History Museum of Utah, Salt Lake City, UT, United States, (5)University of Arizona, Tucson, AZ, United States, (6)Berkeley Geochronology Ctr, Berkeley, CA, United States, (7)Petrified Forest National Park, Petrified Forest, AZ, United States, (8)Martin-Luther-Universität Halle-Wittenberg, Institut für Geowissenschaften, Halle, Germany, (9)Utrecht University, Institute of Environmental Biology, Utrecht, Netherlands, (10)Nanjing Institute of Geology and Palaeontology, State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing, China
The Triassic Period was punctuated by two of the largest Phanerozoic mass-extinctions and witnessed the evolution of elements of the modern biota and the advent of the age of dinosaurs. A rich archive of biotic and environmental changes on land for the early Mesozoic is on the Colorado Plateau, which despite over 100 years of study still remains poorly calibrated in time and poorly registered to other global records. Over 15 years ago, a diverse team of scientists began to develop the concept of a multi-phase, long term Colorado Plateau Coring Project (CPCP). Planning involved two major meetings (DOSECC/NSFICDP supported in Fall, 2007, St. George, UT; and International Continental Drilling Program (ICDP) supported in Spring, 2009, Albuquerque, NM). The National Park Service embraced the concept of Phase One drilling at Petrified Forest National Park (PFNP) in northern Arizona, which exposes one of the most famous and best studied successions of the continental Triassic on Earth, and the Phase One target was decided. Most drilling operation costs were secured from ICDP in Summer, 2010. In late 2013, following more recent NSF support, the research team, utilizing Ruen Drilling Inc., drilled a continuous ~530 m core (60o plunge) through the entire section of Triassic strata (Chinle and Moenkopi fms.) in the north end and a ~240 m core (75o plunge) in lower Chinle and all Moenkopi strata at the south end of the PFNP. Our continuous sampling will place this record in a reliable quantitative and exportable time scale, as a reference section in which magnetostratigraphic, geochronologic, environmental, and paleontologic data are registered to a common thickness scale with unambiguous superposition using pristine samples. The cores are being scanned at the High Resolution X-ray Computed Tomography Facility at UT Austin. They will be transported to the LacCore National Lacustrine Core Facility at U Minnesota, where they will be split, imaged, and scanned for several properties, including XRF data. The core will then be transported to the Rutgers University for sampling. The planning team is contemplating Phase Two options (e.g., the Middle to Lower Triassic marine-influenced section west of the Colorado Plateau (St. George, Utah) area or the Upper Triassic to Lower Jurassic sequence in the Comb Ridge area (Bluff, Utah)).