Algeo,T.J. and Twitchett,R.J.(2010): Anomalous Early Triassic sediment fluxes due to elevated weathering rates and their biological consequences. Geology, 38, 1023-1026.

『上昇した風化速度による異常な初期三畳紀堆積物フラックスおよびそれらによる生物学的結果』


Abstract
 Analysis of 16 marine Permian-Triassic boundary sections with a near-global distribution demonstrates systematic changes in sediment fluxes and lithologies in the aftermath of the end-Permian crisis. Sections from continental-margin and platform settings exhibit higher bulk accumulation rates (BARs) and more clay-rich compositions in the Griesbachian (earliest Triassic) relative to the Changhsingian (latest Permian). These patterns, which largely transcend regional variations in tectonic setting, sequence stratigraphic factors, and facies, are hypothesized to have resulted from a substantial (average 〜7×) increase in the flux of eroded material from adjacent land areas owing to accelerated rates of chemical and physical weathering as a function of higher surface temperatures, increased acidity of precipitation, and changes in landscape stability tied to destruction of terrestrial ecosystems. This sediment surge may have been a contributory factor to the latest Permian marine biotic crisis as well as to the delayed recovery of Early Triassic marine ecosystems owing to the harmful effects of siltation and eutrophication. Contemporaneous deep-sea sections show no increases in sediment flux across the Permian-Triassic boundary owing to their remoteness from continental siliciclastic sources and location below the paleo-carbonate compensation depth.』

Introduction
Methods
Results
Discussion
 Dating uncertainties
 Sequence stratigraphic and tectonic controls on sedimentation
 Biotic consequences of enhanced sediment fluxes
Conclusions
Acknowledgments
References cited


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