A Stratigraphic Analysis and Basin fill History for the Verde Formation, Northern Verde Valley, Central Arizona
Tawnya Hildabrand
Northern Arizona University, School of Earth Sciences and Environmental Sustainability,
Flagstaff, Arizona, USA
[email protected]
The goal of this project is to complete a stratigraphic analysis and basin-fill history for the northern portion of the Verde Valley, which is part of a regional network of basins formed along the western and southern edge of the Colorado Plateau beginning in Miocene time. The primary focus of this research is to document the variations in input of carbonate and siliciclastic sediments during the filling of a tectonically active half graben during the late Miocene and Pliocene. This study will give insight into processes related to tectonically controlled continental basins, which may also relate to climate conditions at the time of deposition. Detailed descriptions of multiple stratigraphic sections will be measured across the northern end of the basin, and applying analytical methods of lacustrine sequence stratigraphy. I will carefully document the changes in sedimentary facies at the transition between siliciclastic-dominated and carbonate-dominated sequences. Field studies will be augmented by petrography (optical and scanning electron microscopy), X-ray diffraction, and gravimetric determinations of carbonate abundance to determine carbonate mineralogy, abundances, and the nature of transitions between carbonate-dominated and siliciclastic-dominated sequences. A pilot study of oxygen and carbon isotopes of primary carbonates will be conducted to explore for a record of changes in precipitation and temperature, which in turn may be related to facies changes. Chemical and isotopic signatures will also be used to aid in correlation of strata across the basin. The results of this work will lay a foundation for future work in the Verde Basin.
AAPG Search and Discovery Article #90183©2013 AAPG Foundation 2013 Grants-in-Aid Projects