Isolating Detrital and Diagenetic Signals in Magnetic Susceptibility Records From Methane‐Bearing Marine Sediments

A new estimate of detrital redox-sensitive metal concentrations and variability in fluxes to marine sediments

The enrichment and depletion of redox sensitive trace metals in marine sediments have been used extensively as paleoredox proxies. The trace metals in shale are comprised of both detrital (transported or particulate) and authigenic (precipitated, redox-driven) constituents, potentially complicating the use of this suite of proxies. Untangling the influence of these components is vital for the i...

Diagenetic formation of ferrimagnetic iron sulphide minerals in rapidly deposited marine sediments, South Island, New Zealand

Detailed magnetostratigraphic studies of Late Neogene siliciclastic sediments of the Awatere Group, South Island, New Zealand (41°45'S, 174°05'E) have revealed a wide range of palaeomagnetic behaviour. Examination of rock magnetic properties was undertaken using conventional palaeomagnetic techniques and thermomagnetic, X-ray diffraction and electron microprobe analyses. These analyses indicate...

Authigenic or detrital origin of pyrrhotite in sediments?: Resolving a paleomagnetic conundrum

Monoclinic pyrrhotite (Fe7S8) is widely claimed to carry magnetizations acquired during early diagenesis in anoxic sedimentary environments. In contrast, geochemical literature indicates that pyrrhotite formation is extremely slow below 180 8C, which makes it a highly unlikely carrier of early diagenetic remanences in sediments. This view is confirmed by the occurrence of late diagenetic Fe7S8 ...

The intensity of chemical weathering: Geochemical constraints from marine detrital sediments of Triassic age in South China

Diagenetic magnetic enhancement of sapropels from the eastern Mediterranean Sea

Diagenetic dissolution of magnetic minerals has been widely observed in organic-rich sediments from many environments. Organic-rich sediments from the eastern Mediterranean Sea (sapropels), recovered during Leg 160 of the Ocean Drilling Program, reveal a surprising catalogue of magnetic properties. Sapropels, from all sites studied across the eastern Mediterranean Sea, are strongly magnetic and...