194 Broad Applications of Thermochronology to Understanding Geologic Rates and Processes Through the Sedimentary Record (Posters)

This session showcases the many ways mid-to-low temperature thermochronometers can be used in isolation or with additional chronometers to understand geologic processes preserved in the sedimentary record such as sediment provenance, source exhumation, burial and/or erosion history.

Tuesday, 21 October 2025
8:00 AM - 5:30 PM
HBGCC, Hall 1

Thermal evolution of the Newark Basin: Insights from Zircon U-Th/He Thermochronology

Paper number: 194-0
Program: Technical Sessions
Time: 8:00 AM – 8:00 AM

Authors

Abstract

Despite extensive study and its value as an analog for modern and fossilized continental rifted margins, key aspects of the tectono-thermal evolution of the Eastern North American Margin (ENAM) remain enigmatic. Triassic-Jurassic syn-rift strata are preserved in a series of primarily east-dipping half-grabens, recording the lithospheric response to rifting that culminated in continental breakup and Atlantic opening. Recent U-Pb provenance data from the Newark Basin record a shift to sediment derived from the footwall during the Norian syn-rift phase, consistent with rift flank uplift during lithospheric necking. However, geochronologic constraints of the tectono-thermal evolution of the Newark Basin during progressive rifting remain limited. Published vitrinite reflectance data are indicative of significant heating and/or burial of the Newark Basin early syn-rift strata and up to 6 km post-rift erosion. This study employs new zircon (U-Th)/He thermochronology to provide new temporal constraints on the rift-to-drift transition of the ENAM. Here we present new zircon (U-Th)/He results and thermochronologic modeling of bedrock samples from both the footwall and hanging wall of the Newark Basin, as well as detrital samples from the Carnian syn-rift Stockton Formation. Mean apparent zircon (U-Th)/He ages from a transect spanning the Newark Basin footwall to hanging wall range between 213 and 169 Ma. In general, mean zircon (U-Th)/He ages decrease toward the basin-bounding fault. The lack of pre- and syn-depositional zircon (U-Th)/He ages preserved in the basin suggests significant post-depositional burial and hydrothermal circulation reset the zircon (U-Th)/He system. Preliminary HeFTy inverse time-temperature models suggest that footwall rocks cooled through the zircon (U-Th)/He partial retention zone between ca. 220 and 180 Ma. Rocks on the hanging wall side, including within the Newark Basin, cooled through the zircon (U-Th)/He partial retention zone between ca. 190 and 150 Ma. The syn-rift cooling of the Newark Basin footwall is consistent with stratigraphic and provenance shifts indicative of rift flank uplift in the Norian. The post-rift cooling of the footwall near the basin-bounding fault is consistent with thermal resetting due to hydrothermal circulation. The results from the hanging wall align with previous vitrinite reflectance studies, indicating significant erosion during the Early Jurassic. Further work will address potential complexities such as the thermal effects associated with the Palisades Sill.

Geological Society of America Abstracts with Programs. Vol. 57, No. 6

doi: 10.1130/abs/2025AM-414322

© Copyright 2025 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.