con(nents, oceans, atmosphere and life evolu(on ricardo trindad

                                                   University  of  São  Paulo                                              Ins4tute  of  Astronomy,  Geophysics  and  Atmospheric  Sciences  

The  Precambrian  Earth:  con1nents,  oceans,  atmosphere  and  life  evolu1on                                                          Ricardo  Trindade  

www.iag.usp.br/interna4onal  

Atmospheric  Sciences  Head  of  Department:  Fabio  Gonçalves  (fabio.goncalves@iag.usp.br)    

v Climatology  v Large  and  Mesoscale  Dynamics  v Ocean-­‐Atmosphere  and  Biosphere-­‐Atmosphere  interac:ons  v Micrometeorology  v Atmospheric  Pollu:on  v Hydrometeorology  

Par:cipa:on  in:  Go-­‐Amazon,  LBA    

Astronomy  Head  of  Department:  Roberto  Costa  (roberto.costa@iag.usp.br)    

Brazilian  coordina:on  of:  GMT,  LLAMA,  mini-­‐CTA,  J-­‐PAS  

v Astrophysics  (stellar,  galac:c  and  extragalac:c)  v Cosmology  v Celes:al  Mechanics  v Astrometry  v Astronomical  Instrumenta:on    

Astrobiology  &  Exoplanets  Group  (AstrobEx)  Coordinator:  Eduardo  Janot  Pacheco  (eduardo.janot@iag.usp.br)    

AstroCam  (Hypobaric  Chamber)    

v Biomolecules  in  protoplatenary  disks  (ALMA)  v Exoplanets  and  habitability  (CoRoT,  KEPLER,  PLATO)  v Biomolecules  on  plametary  atmospheres  

Geophysics  Head  of  Department:  Ricardo  Trindade  (ricardo.trindade@iag.usp.br)    v South  American  Plate  structure  and  dynamics    v Applied  Geophysics  (Environment,  Mineral  Resources)  

Magne:c  anomaly  map  (WDMAM)  

Magne:c  anomaly  map  (WDMAM)  

Electrical  proper:es  in  depth  (resis:vity)  

Li  et  al.  (2013)  Paleo-­‐3  

Li  et  al.  (2013)  Paleo-­‐3  

Li  et  al.  (2013)  Paleo-­‐3  

Li  et  al.  (2013)  Paleo-­‐3  

Age  (Ga)  

Och and Shields (2011) Earth Sci. Rev., Sahoo et al. (2012) Science, Lyons et al. (2014) Nature

Och and Shields (2011) Earth Sci. Rev., Sahoo et al. (2012) Science, Lyons et al. (2014) Nature

Oxida4on  aKer  glacia4on:  Fe  and  Mn  deposits  Mamatwan (Mn), South Africa

Pilbara (Fe), Australia Qudrilátero Ferrífero (Fe), Brazil

Huronian glacial rocks, Canada

Och and Shields (2011) Earth Sci. Rev., Sahoo et al. (2012) Science, Lyons et al. (2014) Nature

Workshop  in  NoVnghan,  April  2014  Accelera:ng  Neoproterozoic  Research  through  Scien:fic  Drilling    Three  key  areas  for  drilling:    v  South  China  (Yangtze  region)  

v West  Brazil  (MS  State)  

v White  Sea  (Russia)  

The  actual  extension  of  glacial  caps:  Did  they  cover  the  en1re  Earth?  

What  did  cause  these  glacial  events?  

Neoproterozoic  Snowball  Earth  

How  did  we  scape  the  Snowball  Earth  events?  

albedo ~ 0.3 pCO2 ~ 1.0 PAL

Hoffman & Schrag (2000). Scientific American, 282 , 68-75

albedo ~ 0.6 pCO2 ~ 0.1 PAL

The  Snowball  Earth  hypothesis:  Freezing  

Results suggest that having continents in tropical latitudes is not

sufficient to bring the Earth in total freeze: Snowball

Earth

Donnadieu et al. (2004) Nature

Freezing  the  Earth:  Climate  and  Geochemical  model  

Supercontinent configuration (800 Ma): -  pCO2 equilibrates at 1800 ppm -  It corresponds to na average surface temperature of 10.2 °C

Donnadieu et al. (2004) Nature

Freezing  the  Earth:  Climate  and  Geochemical  model  

Dispersed continents (Rodinia Break-Up at 750 Ma): -  pCO2 equilibrates at 500 ppm -  It corresponds to na average surface temperature of 2 °C (-8.2 °C)

A paleogeography with dispersed continents is more favorable to CO2

drawdawn.

It may trigger a large glaciation but not a Snowball Earth

Redox  evolu1on  aKer  glacial  events?  

Mul1ple-­‐layered  stra1fied  oceans  (local  vs.  global  signals)?  

Neoproterozoic  Oxygena1on  Event  

Ocecan  and  atmospheric  oxygena1on  and  biological  evolu1on  

 δ13CDIC  (‰)

DIC<2 mM

DIC>10 mM

depth  (m

)

0

20

40

60

80

0 2 4 -­‐2 -­‐4 -­‐6 Volcanic Lake Pavin (France)

Meromitic, Stratified

(Assayag et al., 2006, Appl. Geochem.)

Ocean redox stratification and metabolic paths

Ccarb from OM

Ccarb from CH4

Ccarb from atm CO2

Ader  et  al.  (2009)  EPSL  

Ader  et  al.  (2009)  EPSL  

Doushantuo  Forma:on,  South  China  

Ader  et  al.  (2009)  EPSL  

…  But  do  animals  require  a  lot  of  oxygen?  

Sperling  et  al.  (2013)  EPSL    

Experiments  with  the  AstroCam:  Can  we  iden:fy  plesiomorphic  adapta:ons  of  early  metazoans  to  Neopropterozoic  ocean  chemistry  on  extant  animal  phyla?  

In  fact,  oxygen  rise  may  have  been  driven  by  biological  innova:on…  

Lenton  et  al.  (2014)  Nat.  Geosciences  

low O2 flux

high O2 flux

Did life evolution had impact on oxygenation? (Logan et al., 1995, Cohen et al., 2009)

To be tested through Sulphur isotopes…

Och  and  Shields-­‐Zhou,  2011  

Fike and Grotzinger, 2008

Mul:ple  sulphur  isotopes  =  insight  into  the  non  steady  state  model  

30%  

60%  

Coupling between carbon and sulphur cycles

CO2  +  H2O  <=>  CH2O  +  O2   2CH2O  +  SO42-­‐  <=>  2HCO3-­‐  +  H2S  

Forg   Fpyr  

Photosynthesis   Bacterial  sulphate-­‐reduc:on  (BSR)  

O2  produc:on,  NOE  

=  Increase  of  30  to  70  %  PAL  pO2    

Thanks

2CO2  +  2H2O  <=>  2CH2O  +  2O2  

2CH2O  +  SO42-­‐  <=>  2HCO3

-­‐  +  H2S  

 [SO42-­‐]  =  3  -­‐  6  mM     8*1018  mol  of  sulphate,    

60%  (from  dis:lla:on)  =  5.6*1018  mol      

1.2*1019  mol  of  O2  liberated  into  the  Oc-­‐At  system  

=  Increase  of  30  to  70  %  PAL  pO2    

«  Back-­‐of-­‐the-­‐envelope  »  O2  quan:fica:on  

Es:ma:on  of  Kah  et  al.  2004  

*Vocean  I  

II  

III  

IV  

Catling  2011  Sansjofre  et  al.,  submised