48 Recent Advances in Basin-and-Range and Proterozoic Geology of the Western U.S. III: A Session Honoring Ernie Duebendorfer

Wednesday, 16 May 2018
3:30 PM - 5:15 PM
Kaibab Room

INTEGRATING SPATIAL AND TEMPORAL VARIABILITY IN DETRITAL ZIRCON PROVENANCE STUDIES; A CASE STUDY FROM THE INTERIORLY-DRAINED MESOPROTEROZOIC BELT BASIN

Paper number: 48-6
Program: Symposia Sessions
Time: 4:55 PM – 5:15 PM

Authors

Abstract

The Belt Supergroup is a succession more than fifteen km. thick of slightly metamorphosed, mostly sedimentary rocks without an unconformity or incised marine sequence boundary. Instead it is a fluvial and lacustrine unit, which, based on stratigraphy and petrology, received sediments from west, south, and east sides of the basin (present coordinates). As lacustrine sediments filled the internally drained basin, base level of the flat lake floors and the surrounding gently sloping terrestrial surfaces rose, limiting incision. Formations deposited across these surfaces were broad and extensive.

Using multi-dimensional scaling, we statistically cataloged detrital zircon dates from 72 samples throughout the Belt basin in order to substantiate spatial and temporal trends in sedimentary provenances within Belt formations. Detrital zircon signatures are characterized by variable mixing between end member age populations and are largely controlled by geographic and stratigraphic position. Detrital zircon signatures within Belt formations change laterally, and within 180 km loose their distinctive character, indicating mixing of source terrains and limited transport distances. These results show that in the Belt basin, statistically defined detrital zircon populations cannot be used to correlate formations lithostratigraphically or chronostratigrphically beyond distances of ~200 km. This study highlights the importance of quantifying spatial variability in detrital zircon provenance and correlation studies of formations in internally drained sedimentary basins.

Geological Society of America Abstracts with Programs. Vol. 50, No. 5

doi: 10.1130/abs/2018RM-314406

© Copyright 2018 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.