Biomarker in Heinrich event layers


Autoria(s): Rashid, Harunur; Grosjean, Emmanuelle
Cobertura

MEDIAN LATITUDE: 50.807667 * MEDIAN LONGITUDE: -47.520333 * SOUTH-BOUND LATITUDE: 43.240000 * WEST-BOUND LONGITUDE: -56.460000 * NORTH-BOUND LATITUDE: 58.240000 * EAST-BOUND LONGITUDE: -32.580000

Data(s)

09/07/2006

Resumo

There are controversies regarding the origin of Heinrich layer 3 (H3), the massive ice-rafting and meltwater event in the North Atlantic during the last glacial cycle spanning a time window between 29 and 30 kyr B.P. Some argue in favor of a Laurentide Ice Sheet source similar to other Heinrich layers, while a contending view argues for the European ice sheet source. Existing geochemical proxies such as 40Ar/39Ar, 206Pb/204Pb, or epsilon-Nd, etc., could not be used to distinguish among various sources of ice-rafted debris in H3 because of their low abundances, suggesting a background glacial sediment signal. In order to circumvent this problem a biomarker-based approach is used to characterize the provenance of H layers 2, 3, and 4 and other non-Heinrich layers. The presence of hopanes and steranes and their aromatic counterparts in the H layers is incompatible with Recent sediments and is attributed to the transportation of organic matter because of the glacial erosion of source rocks. The most diagnostic and useful signatures of this ancient organic matter in the H layers are the dominance of C34 hopanoids over C33 and the occurrence of isorenieratane along with palaerenieratane. Biomarkers signatures in H layers 2 and 3 of the Labrador Sea suggest no difference in their source. Hydrocarbon distributions suggest that these sediments were derived from the Middle to Late Ordovician and Silurian source rocks of the Hudson Bay of eastern Canada. Biomarker data of the H layer 4 from the northwest Atlantic reveal that the sediments of this layer have a similar source to the H layers in the Labrador Sea.

Formato

application/zip, 2 datasets

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.833897

doi:10.1594/PANGAEA.833897

Idioma(s)

en

Publicador

PANGAEA

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Fonte

Supplement to: Rashid, Harunur; Grosjean, Emmanuelle (2006): Detecting the source of Heinrich layers: An organic geochemical study. Paleoceanography, 21(3), PA3014, doi:10.1029/2005PA001240

Palavras-Chave #aromatic 8,14; aromatic secohopanoid ratios C29/C30; aromatic secohopanoid ratios C33/34; aromatic secohopanoid ratios C35/C34; C27 sterane; C28 sterane; C28S triaro; C28S triaromatic steroid; C29 alpha alpha alpha 20S/(20S + 20R); C29 sterane; Depth; Depth, bottom/max; DEPTH, sediment/rock; Depth, top/min; Depth bot; Depth top; Event; Hopane, total; Hopane: C27beta/(Ts+Tm); Hopane: C29H/C30H; Hopane: C33H/C34H; Hopane: C35H/C34H; Hopane: Ts/Tm; Hopane tot; Isorenieratane, per unit sediment mass; Isorenieratane/sed; Palaerenieratane, per unit sediment mass; Palaerenieratane/sed; Ratio; Secohopanoids, per unit sediment mass; Secohopanoids/sed; Sediment; Sediment type; Sterane C29beta alpha R/C29 alpha alpha alpha R; Steranes; Steranes, total; Steroids, total per unit sediment mass; Steroids tot/sed; triaromatic
Tipo

Dataset