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Trace metals as paleoredox and paleoproductivity proxies: An update
Abstract This paper is a synthesis of the use of selected trace elements as proxies for reconstruction of paleoproductivity and paleoredox conditions. Many of the trace elements considered here showExpand
Trace-element behavior and redox facies in core shales of Upper Pennsylvanian Kansas-type cyclothems
The black shale submember of core shales of Pennsylvanian Kansas-type cyclothems is highly enriched in redox-sensitive trace elements (TEs) relative to the overlying gray shale submember as well asExpand
Environmental analysis of paleoceanographic systems based on molybdenum–uranium covariation
Abstract Modern low-oxygen marine systems exhibit patterns of molybdenum–uranium covariation that can be linked to specific attributes and processes of the depositional system, including (1)Expand
Mo–total organic carbon covariation in modern anoxic marine environments: Implications for analysis of paleoredox and paleohydrographic conditions
[1] Sedimentary molybdenum, [Mo]s, has been widely used as a proxy for benthic redox potential owing to its generally strong enrichment in organic-rich marine facies deposited under oxygen-depletedExpand
Natural fractionation of 238U/235U
Abstract The isotopic composition of U in nature is generally assumed to be invariant. Here, we report variations of the 238 U/ 235 U isotope ratio in natural samples (basalts, granites, seawater,Expand
Terrestrial-marine teleconnections in the Devonian: links between the evolution of land plants, weathering processes, and marine anoxic events
The Devonian Period was characterized by major changes in both the terrestrial biosphere, e.g. the evolution of trees and seed plants and the appearance of multi-storied forests, and in the marineExpand
Sedimentary Corg:P ratios, paleocean ventilation, and Phanerozoic atmospheric pO2
The Corg:P ratios of organic-rich facies (TOCN1%) exhibit considerable variation through the Phanerozoic, from b10:1 in the Permian Phosphoria Formation to N1000:1 in some Devonian black shales.Expand
Terrestrial–marine teleconnections in the collapse and rebuilding of Early Triassic marine ecosystems
Abstract The latest Permian mass extinction (LPE), just prior to the Permian–Triassic boundary at ~ 252 Ma, resulted in the disappearance of ~ 90% of skeletonized marine taxa and the replacement ofExpand
The Late Pennsylvanian Midcontinent Sea of North America: A review
Abstract The Late Pennsylvanian Midcontinent Sea (LPMS) of North America reached its greatest extent (~ 2.1 × 106 km2) during glacioeustatic highstands from the Middle Pennsylvanian to the EarlyExpand