Stable isotope and organic biomarker analysis of the late Proterozoic Coppercap formation in the MacKenzie Mountains

Sulfur and carbon stable isotope ratios and organic biomarker abundance were performed on drill core samples from the Coppercap Formation of the Coates Lake Group in the Windermere Supergroup of the MacKenzie Mountains to reconstruct an environmental condition proceeding the first Neoproterozoic Snowball Earth event. The Coppercap Formation directly underlies the Rapitan Group, Sturtian glacigenic deposits, and represents a depositional environment existing directly before the Cryogenian glacial episodes. Based on aryl isoprenoids, n-propyl cholestane, isopropyl cholestane, total organic carbon, carbonate mineral analysis, [delta]34S from pyrite, [delta]13Corganic and [delta]13Ccarbonate values, environmental conditions of the Coppercap Formation were reconstructed. The Coppercap Formation was found to be a shallow euxinic marine basin with purple and green sulfur bacteria microbial mats. This suggest persistent hydrogen sulfide rich waters in the shallow photic zone persisted until the Sturtian.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2010

Author dc:creator

• Thomas, Katherine S., S.M. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Shuhei Ono.

• Earth, Atmospheric, and Planetary Sciences.

Statement dc:rights

• MIT theses are protected by copyright. They may be viewed, downloaded, or printed from this source but further reproduction or distribution in any format is prohibited without written permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/114138

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/114138