Universität zu Köln

Dummann, W., Schroder-Adams, C., Hofmann, P., Rethemeyer, J. and Herrle, J. O. (2021). Carbon isotope and sequence stratigraphy of the upper Isachsen Formation on Axel Heiberg Island (Nunavut, Canada): High Arctic expression of oceanic anoxic event 1a in a deltaic environment. Geosphere, 17 (2). S. 501 - 520. BOULDER: GEOLOGICAL SOC AMER, INC. ISSN 1553-040X

Full text not available from this repository.

Abstract

The Early Cretaceous oceanic anoxic event (OAE) 1a documents a major perturbation of the global carbon cycle with severe consequences for the ocean-climate-biosphere system. While numerous studies over the past decades have provided a relatively detailed picture of the environmental repercussions of OAE 1a at low and mid-latitudes, studies from high latitudes, in particular the High Arctic, are limited. In this study, we present a high-resolution carbon isotopic and sequence stratigraphic framework for the lower to lower upper Aptian interval of the Isachsen Formation of the High Arctic Sverdrup Basin (Canada). These data enable us to precisely locate the stratigraphic position of OAE 1a in a deltaic sedimentary environment. The carbon isotope record allows, for the first time, identification of the different carbon isotope segments (CISs) of OAE 1a in the Sverdrup Basin and thereby correlation of the High Arctic record with sections from lower latitudes. Based on this improved chemostratigraphy, we revise the age of upper Paterson Island, Rondon, and Walker Island Members, important regional lithostratigraphic marker units. Whole-rock geochemical data record two episodes of marine incursion into the Sverdrup Basin during OAE 1a (CISs Ap3 and Ap6), which are interpreted as regional maximum flooding surfaces. This information is used in conjunction with detailed sedimentological logs and geochemical grain-size proxies to refine the sequence stratigraphic framework for the upper Isachsen Formation. We propose that transgressive-regressive cycles in the Sverdrup Basin were controlled mainly by the combined effects of eustatic sea-level changes and regional tectonic uplift, potentially related to the emplacement of Alpha Ridge, which culminated at ca. 122 Ma during CIS Ap9.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Dummann, W. UNSPECIFIED UNSPECIFIED UNSPECIFIED Schroder-Adams, C. UNSPECIFIED UNSPECIFIED UNSPECIFIED Hofmann, P. UNSPECIFIED UNSPECIFIED UNSPECIFIED Rethemeyer, J. UNSPECIFIED UNSPECIFIED UNSPECIFIED Herrle, J. O. UNSPECIFIED UNSPECIFIED UNSPECIFIED
URN:	urn:nbn:de:hbz:38-581270
DOI:	10.1130/GES02335.1
Journal or Publication Title:	Geosphere
Volume:	17
Number:	2
Page Range:	S. 501 - 520
Date:	2021
Publisher:	GEOLOGICAL SOC AMER, INC
Place of Publication:	BOULDER
ISSN:	1553-040X
Language:	English
Faculty:	Unspecified
Divisions:	Unspecified
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language EARLY CRETACEOUS CARBON; ROQUEFORT-LA BEDOULE; SVERDRUP BASIN; INTEGRATED STRATIGRAPHY; ORGANIC-CARBON; HYDRATE DISSOCIATION; ORBITAL CHRONOLOGY; CLIMATE-CHANGE; PYRITE SULFUR; BLACK SHALES Multiple languages Geosciences, Multidisciplinary Multiple languages
URI:	http://kups.ub.uni-koeln.de/id/eprint/58127