Millimeter-scale profiling of abyssal marine-sediments - role of bioturbation in early sterol diagenesis

Conte, MH; Madureira, LAS; Eglinton, G; Keen, D; Rendall, C

HERO ID

4936628

Reference Type

Journal Article

Year

1994

Language

English

HERO ID 4936628
In Press No
Year 1994
Title Millimeter-scale profiling of abyssal marine-sediments - role of bioturbation in early sterol diagenesis
Authors Conte, MH; Madureira, LAS; Eglinton, G; Keen, D; Rendall, C
Journal Organic Geochemistry
Volume 22
Issue 6
Page Numbers 979-990
Abstract Near surface sediments from an abyssal northeast Atlantic site were sectioned using a newly designed Precision Core Extruder (PCE). Downcore profiles of excess Pb-210 and sterols showed pronounced millimeter-scale variability reflecting specific degradation and bioturbation processes. Excess Pb-210 and sterol concentrations decreased sharply in the uppermost 5 mm, and pronounced subsurface maxima were present. Stanol/stenol ratios, and the relative abundance of cholesterol, increased below 10 mm, indicating biodegradation involving Delta(5) double bond hydrogenation, C-24 dealkylation and/or de novo synthesis. Sterol profiles indicate that early diagenesis of labile compounds is dominated by processes operating near the sediment/water interface, and that the penetration of labile material into oxic sediments is largely controlled by advective processes, associated with infaunal feeding rather than diffusive-like mixing.
Doi 10.1016/0146-6380(94)90032-9
Wosid WOS:A1994QT59000007
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English
Keyword SURFACE SEDIMENTS; STEROLS; BIOTURBATION; EARLY DIAGENESIS; NORTH ATLANTIC; PB-210