Cullen D Kortyna
M.S., Geosciences, The University of Arizona, 2013
Ph.D., Geosciences, The University of Texas at Austin, expected 2021
I am broadly interested in the controls on and dynamics of sediment routing systems. I investigate this at both the sedimentary basin scale, where I apply detrital geo-thermochronometry and other sedimentary provenance techniques, and at the outcrop scale, where I apply sedimentological and stratigraphic techniques, to evaluate sedimentary system response to tectono-climatic perturbations.
Project 1: Tectonic Controls on Laramide-Mexican Sediment Routing Through South Texas
For this project, I leverage detrital zircon U-Pb-He double dating to determine sediment sources and routing pathways through West Texas and South Texas during the Late Cretaceous to Paleogene. The combined provenance and exhumation proxies allow me to explore the fundamental control inherited Border Rift architecture, both through remnant topography and reactivated structures during Laramide-Mexican orogenesis, played in guiding sediment routing through the Border Region towards the Gulf of Mexico. Furthermore, the U-Pb-He double dating allows me to construct time-temperature histories of sediment source terranes in the Border Region that have since been overprinted by Basin and Range extension, providing insight into Late Cretaceous-Paleogene exhumation in the region and a framework for making sediment budget estimates.
Project 2: Fluvial Sedimentary Response to Tectono-Climatic Perturbations in West Texas
Paleogene fluvial strata of the Tornillo Group in West Texas was deposited during a period of regional tectonic activity and global climatic variation. The basin was bounded on its SW and NE margins by growing Laramide-Mexican monoclines resulting in both thickness variations and angular growth relationships in the Tornillo strata. Furthermore, the Tornillo Group was deposited continuously during major Paleogene hyperthermal events, including the PETM and ETM 2 and 3, which have been correlated to coarse grained sandstone intervals within the stratigraphy. In this project, I am studying how the kinematic behavior of the Tornillo Group fluvial systems responded to tectono-climatic perturbations. To do so, I am employing a combination of traditional stratigraphic techniques, including channel belt mapping and documentation of bar-scale strata, with new photogrammetry techniques to make robust models of the kinematic evolution of fluvial channel belts through the Tornillo Group.
Current Research Projects
Tectonic Controls on Laramide-Mexican Sediment Routing Through South Texas
Fluvial Sedimentary Response to Tectono-Climatic Perturbations in West Texas
Past Research Projects
Structural and Thermochronometric Constraints on Salta Rift Inversion
Provenance Signature of a Forearc Basin Modified by Spreading Ridge Subduction, Southern Alaska
GSA Graduate Student Research Grant - The Geological Society of America (2019)
AAPG Grants-in-Aid - American Association of Petroleum Geologists (2019)
Equinor Fellows Program - Equinor (2018 - 2021)
Detrital zircon U-Pb-He double dating constraints on Laramide hinterland magmatism, tectonism, exhumation, and sediment routing - insights from the Tornillo Basin, West Texas, American Geophysical Union Fall Meeting, (2020)
Sediment Dispersal to the distal Late Cretaceous-Paleogene Mexican broken foreland from detrital zircon U-Pb geochronology, GSA South Central Section Meeting, Fort Worth, TX (2020)
Deciphering Sediment Source Exhumation Histories and Rates to the Paleocene-Eocene Paleo-Rio Grande River System from Detrital Zircon U-Pb-He Double Dating, GSA Annual Meeting, Phoenix, AZ (2019)
Tectonomorphic Influence on Late Cretaceous-Paleogene Sediment Provenance and Dispersal Through West and South Texas From Detrital Zircon Geochronology, AAPG Annual Convention and Exhibition, Salt Lake City, UT (2018)
Provenance and Pathways of the Cretaceous-Paleogene Rio Grande River: Deciphering Between Signals from Complex Source Terranes Using Detrital Zircon Geochronology, AGU Fall Meeting, New Orleans, LA (2017)
Tectonomorphic Influence on Sediment Sources and Pathways through West Texas: Detrital Zircon Geochronology of the Late Cretaceous-Paleogene Tornillo Basin, Big Bend National Park, GSA Annual Meeting, Seattle, WA (2017)
Provenance Signature of a Forearc Basin Modified by Spreading Ridge Subduction: Detrital Zircon Geochronology and Detrital Modes from the Paleogene Arkose Ridge Formation, Southern Alaska, GSA Fall Meeting, Denver, CO (2010)
Sedimentology, paleontology, and structural framework of the central Arkose Ridge Formation, Talkeetna Mountains, Alaska, GSA Fall Meeting, Portland, OR (2009)
Kortyna, C., Donaghy, E., Trop, JM. & Idleman, B. (2014). Integrated provenance record of a forearc basin modified by slab-window magmatism: detrital-zircon geochronology and sandstone compositions of the Paleogene Arkose Ridge Formation, south-central Alaska. Basin Research, 26(3), 436-460. https://onlinelibrary.wiley.com/doi/full/10.1111/bre.12033. doi:.
Kortyna, C., DeCelles, P. & Carrapa, B. (2019). Structural and thermochronologic constraints on kinematics and timing of inversion of the Salta rift in the Tonco-Amblayo sector of the Andean retroarc fold-thrust belt, northwestern Argentina. Andean Tectonics, 429-464. https://www.sciencedirect.com/science/article/pii/B9780128160091000186. doi:.