Skip to Main Content
GEOREF RECORD

Reconstructing paleocatchments by integrating stable isotope records, sedimentology, and taphonomy; a Late Cretaceous case study (Montana, United States)

Brady Z. Foreman, Henry C. Fricke, Kyger C. Lohmann and Raymond R. Rogers
Reconstructing paleocatchments by integrating stable isotope records, sedimentology, and taphonomy; a Late Cretaceous case study (Montana, United States)
Palaios (September 2011) 26 (9): 545-554

Abstract

Robust isotopic reconstructions of climate, elevation, and biology require a reasonable capture of the range of isotopic variability across a paleolandscape. Here, we illustrate how integrating multiple proxies derived from a variety of paleoenvironments aids in this effort. We determined delta (super 18) O and delta (super 13) C values from lake and soil carbonates, unionid shells, gar scales, and crocodile teeth from multiple depositional environments (lakes, soils, ponds, streams, and large rivers) spanning a 300 km proximal-to-distal transect within the Late Cretaceous foreland basin of Montana. Two major patterns emerge. First, quiet water environments display higher delta (super 18) O and lower delta (super 13) C values than large rivers, which indicates greater input from local precipitation compared to high-altitude runoff, and a relatively larger contribution of degraded vegetative matter to the dissolved inorganic carbon load. Second, proxies with seasonal biases toward late spring and summer growth display lower delta (super 18) O and delta (super 13) C values in the basin proximal setting compared to the distal coastal setting, which is linked to the rainout history of vapor masses moving across the foreland basin. Overall these isotopic patterns mirror those in modern catchments, support hypotheses of monsoonal rainfall within the basin, and suggest a hypsometric mean elevation of approximately 2.6 km within the Sevier orogenic belt. Furthermore, our results indicate a potential to subdivide freshwater paleoecosystems to refine paleobiologic studies of habitat preference and migration patterns.


ISSN: 0883-1351
Serial Title: Palaios
Serial Volume: 26
Serial Issue: 9
Title: Reconstructing paleocatchments by integrating stable isotope records, sedimentology, and taphonomy; a Late Cretaceous case study (Montana, United States)
Affiliation: University of Michigan, Department of Geological Sciences, Ann Arbor, MI, United States
Pages: 545-554
Published: 20110901
Text Language: English
Publisher: Society for Sedimentary Geology, Tulsa, OK, United States
References: 81
Accession Number: 2011-080450
Categories: StratigraphyIsotope geochemistry
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. 2 tables, sect., strat. col., sketch map
N47°00'00" - N49°00'00", W113°00'00" - W109°00'00"
Secondary Affiliation: Colorado College, USA, United StatesMacalester College, USA, United States
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data from GeoScienceWorld, Alexandria, VA, United States. Reference includes data supplied by SEPM (Society for Sedimentary Geology), Tulsa, OK, United States
Update Code: 201144
Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal