Geochemistry of the Cambrian Sirius Passet Lagerstätte, Northern Greenland

TY - JOUR

T1 - Geochemistry of the Cambrian Sirius Passet Lagerstätte, Northern Greenland

AU - Le Boudec, Ange

AU - Ineson, Jon

AU - Rosing, Minik Thorleif

AU - Døssing, Lasse Nørbye

AU - Martineau, Francois

AU - Lécuyer, Christophe

AU - Albarède, Francis

PY - 2014/4

Y1 - 2014/4

N2 - The lower Cambrian Sirius Passet Lagerstätte (∼518 Ma) consists of mudstones about 8 m thick located in the Franklinian Basin of North Greenland. We analyzed major and trace elements plus the S, C, Cu, Fe, Zn, and Mo isotope compositions. Factor analysis allowed the lithology of the mudstone to be broken down into variable proportions of two inputs, a dry felsic component and a hydrous mafic component (smectite or chlorite). Zircons U-Pb ages indicate multiple sources, the local Proterozoic basement of Northern Greenland (1250-2400 Ma) and Pan-African felsic magmas (620-650 Ma) from across the Iapetus ocean. Diagenesis involved the reduction of Fe, S, and Mo from seawater and pyritization. The Sirius Passet Lagerstätte formed in oxygen-starved muds inhibiting degradation of organic matter underneath a well-ventilated water column. The chemistry of the samples, their very fine grain size, their apparent lack of graded bedding, and the age of zircons suggest that the Lagerstätte may represent wind-blown dust deposited on the continental slope. Key Points Geochemistry of one of the most important Lagerstätte Cambrian explosion triggered by wind-blown fertilization of the ocean Continent assembly and high tectonic plateaus are part of biogeochemical cycles

AB - The lower Cambrian Sirius Passet Lagerstätte (∼518 Ma) consists of mudstones about 8 m thick located in the Franklinian Basin of North Greenland. We analyzed major and trace elements plus the S, C, Cu, Fe, Zn, and Mo isotope compositions. Factor analysis allowed the lithology of the mudstone to be broken down into variable proportions of two inputs, a dry felsic component and a hydrous mafic component (smectite or chlorite). Zircons U-Pb ages indicate multiple sources, the local Proterozoic basement of Northern Greenland (1250-2400 Ma) and Pan-African felsic magmas (620-650 Ma) from across the Iapetus ocean. Diagenesis involved the reduction of Fe, S, and Mo from seawater and pyritization. The Sirius Passet Lagerstätte formed in oxygen-starved muds inhibiting degradation of organic matter underneath a well-ventilated water column. The chemistry of the samples, their very fine grain size, their apparent lack of graded bedding, and the age of zircons suggest that the Lagerstätte may represent wind-blown dust deposited on the continental slope. Key Points Geochemistry of one of the most important Lagerstätte Cambrian explosion triggered by wind-blown fertilization of the ocean Continent assembly and high tectonic plateaus are part of biogeochemical cycles

U2 - 10.1002/2013GC005068

DO - 10.1002/2013GC005068

M3 - Journal article

SN - 1525-2027

VL - 15

SP - 886

EP - 904

JO - Geochemistry, Geophysics, Geosystems

JF - Geochemistry, Geophysics, Geosystems

IS - 4

ER -