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Turbulent Times for Early Animals?. By Swapan Kr Sahoo Ganqing Jiang, Noah Planavsky, Brian Kendall, Jeremy Owens, Ariel Anbar And Timothy Lyons 125th GSA Annual Meeting Denver, Colorado 30 th October, 2013. Department of GEOSCIENCE. University of Nevada, Las Vegas. - PowerPoint PPT Presentation
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BY
SWAPAN KR SAHOOGANQING JIANG, NOAH PLANAVSKY, BRIAN KENDALL, JEREMY OWENS, ARIEL ANBAR
AND TIMOTHY LYONS
125TH GSAANNUAL MEETINGDENVER, COLORADO30TH OCTOBER, 2013
TURBULENT TIMES FOR EARLY ANIMALS?
UNIVERSITY OF NEVADA, LAS VEGAS
Department of
GEOSCIENCE
Rise of Atmospheric O2Early Metazoans–632 Ma, Early O2 –2.3 Ga
Fossil and Metal Record
after Sahoo et al., 2012
after Lyons et al., 2009, Elements
after Sahoo et al., 2012, Nature
Early Proterozoic - GOE ~2.4 Ga
Late Proterozoic ~551 Ma
Early Metazoans~632 Ma
Trace Metals and Isotopes Rise of Early Animals and O2Evidence from Redox sensitive Metals
after Sahoo et al., 2012, Nature
Trace Metals and Oxygen Seawater Metals Record RedoxMetal/TOC Ratio’s Record Conc.
The sedimentary Metal/TOC* ratios track dissolved Metal concentration in seawater. *TOC Total Organic Carbon
Seawater Trace metals records information about marine redox landscape.
Mod
ern
Sedi
men
tsAn
cien
t
after Lyons et al., 2008, ESR
Redox Indicators How to calculate the chemical condition of the ocean
Iron (FeT)
Highly Reactive Fe (FeHR)
Non Reactive Fe (FeNR)
Fe Oxide (FeOxide)Fe Magnetite (FeMag)Fe Carbonate (FeCarb)Fe Pyrite (FePyrite)
Oxic vs. Anoxic
(FeHR/FeT)
Ferruginous vs. Euxinic (FePyrite/FeHR)
=
after Poulton and Canfield, 2011, Elements
Geology-Rock Record Study area, Location Maps and Age constrains for the Nanhua Basin
and Jiang et al., 2011, Gondwana Research
after Sahoo et al., 2012, Nature
The redox state of the ocean was euxinic, and record original signature of the ocean chemistry
SEM Analysis Pyrite Framboids - syngenetic depositional history
Backscattered electron (BSE) images of closely packed, typical pyrite framboids
after Sahoo et al., 2012, Nature
Multi-Proxy Geochemical Data Rise and Fall of Redox sensitive Metals
If no redox change across major boundaries, but metal enrichments: then1. Either there are change in fluxes —weathering
2. Change in oxidative state of the ocean
Geochemical Modeling Weathering Alone is not the DriverOxidation is the key
Even 1% Anoxic/euxinic sediments can counter balance even double the riverine flux. not the major driver
The oxidative state of the ocean was a primary driver for high Trace metalsafter Sahoo et al., 2012, Nature
Animals, Nutrients and O2Diversification Limited to certain
intervals. Rise and Fall of O2?
The Precambrian/Cambrian boundary – ocean chemistry was very much like Phanerozoic
— Low Fe, P but high Mo, V, U, Co, Cd (Chalcophilic bioessential metals)
We should question our self with Late Ediacaran biospheric evolution 1. Nutrient limitation feedbacks at various redox regimes
2. The protracted nature of Earth’s O2 rise
Acknowledgement Lot of People to ThankFriends and Colleagues
S.K. Sahoo G. Jiang N. Planavsky T. Lyons B. Kendall A. D. Anbar
X. Wang C. Scott
National Foundation of SciencesUniversity of California, RiversideLyons Lab: Jeremy Owens, Chris, Natasha, Megan and Steve Bates
Arizona State University, TempeGwyneth Gordon, Steve Romanielo
China University of Geosciences
University of Nevada, Las VegasCarbonate Mafia Group and Jeevan Jayakody
Thank You