Skip to Main Content
Book Chapter

Genetic Characteristics of Glauconite and Siderite: Implications for the Origin of Ambiguous Isolated Marine Sandbodies

By
Sharon A. Stonecipher
Sharon A. Stonecipher
Marathon Oil Company, P.O. Box 269, Littleton, CO 80160 U.S.A.
Search for other works by this author on:
Published:
January 01, 1999

Abstract

Authigenic glauconite and siderite form under a limited range of well-documented geological and geochemical conditions. Because glauconite precursors need to remain at or near the sediment water surface for long periods of time in a setting where they can be repeatedly exhumed and shallowly buried, glauconite typically develops on the outer margins of continental shelves in areas of low sediment input. Based on these requirements, glauconite has traditionally been used as an indicator for transgressive sequences because transgressions tend to trap sediment on the continents. However, from a sequence stratigraphic standpoint, glaucony may be present in virtually any part of a depositional sequence due to remobilization. Glaucony can provide useful information for sequence stratigraphy only if variations in its abundance, physicochemical properties, and spatial/temporal characteristics are carefully documented.

Siderite typically forms in one of two distinct environments: one characterized by strongly reducing conditions (methanogenic zone), and one under slightly reducing conditions (post-oxic zone). Methanogenic siderite is more common in continental and fresh-water lacustrine than marine deposits. Post-oxic conditions are commonly associated with marine environments exhibiting moderately low concentrations of organic matter and low sedimentation rates. Siderite is also frequently found in association with sequence boundaries where it occurs as a secondary cement below the lowstand surface of erosion (LSE).

These restrictions on environment of origin provide information on the hydrologic regime and, by inference, the depositional and sequence stratigraphic setting of the host sediment in which these minerals are found. By examining the genetic significance of minerals such as glauconite and siderite, the origin of ambiguous, controversial, isolated marine sand bodies such as those discussed elsewhere in this volume may be clarified. This paper summarizes what is currently known about the chemical characteristics of these minerals and discusses generalized models of their distribution in a variety of sequence stratigraphic settings.

You do not currently have access to this article.

Figures & Tables

Contents

SEPM Special Publication

Isolated Shallow Marine Sand Bodies: Sequence Stratigraphic Analysis and Sedimentologic Interpretation

Katherine M. Bergman
Katherine M. Bergman
Department of Geology University of Regina Regina SK S4S OA2 Canada
Search for other works by this author on:
John W. Snedden
John W. Snedden
Mobil Exploration & Producing Technical Center PO Box 650232 Dallas TX 75265USA
Search for other works by this author on:
SEPM Society for Sedimentary Geology
Volume
64
ISBN electronic:
9781565761865
Publication date:
January 01, 1999

GeoRef

References

Related

Citing Books via

Close Modal
This Feature Is Available To Subscribers Only

Sign In or Create an Account

Close Modal
Close Modal