Evolution of the Atmosphere, climate, and life

on Earth

The International Symposium on Multidisciplinary Sciences on the Earth

Eiichi Tajika

University of Tokyo

November 19, 2014

1. Introduction

Evolution of Atmosphere

[modified from Kasting (2005) Scientific American]

CO2

CH4

O2

Age (Ga; billion of years ago)

Rel

ativ

e C

once

ntra

tion

→

N2

2. Overview: Recent Progress of Studies on

Rise of Oxygen

N2 78%

O2 21%

Ar 1%

Oxygen in the Atmosphere Partial pressure of oxygen controls

“redox” (reduction and oxidation) condition of the surface environment

How and why has oxygen risen in the atmosphere?

Cyanobacteria The first oxygenic photosynthetic life

CO2 + H2O → CH2O + O2

[http://ja.wikipedia.org/wiki/%E8%97%8D%E8%97%BB]

[Farquhar et al. (2003) Geobiology]

＊MIF-S may be derived from the photochemical reactions in the upper atmosphere with UV flux from the Sun ＊It does not occur when the atmosphere contains oxygen (>10-5 PAL)

(negative Δ33S) (positive Δ33S)

Photochemical Reactions

A New Indicator of Atmospheric Oxygen Mass-independent Fractionation (MIF) of Sulfur Isotopes

4

3

2

1

0

-1

-2

Δ33S

(‰)

Stage I StageII Stage III

4 3 2 1 0 Age (Ga; billion years ago)

[Farquhar et al. (2000) Science, Farquhar et al. (2003) Geobiology]

MIF-S disappears after about 2.45 Ga (billion years ago) → Evidence for a rise of oxygen in the atmosphere (＞10-5 PAL)

Difference from mass-dependent fractionation (MDF)

Mass-independent Fractionation (MIF) of Sulfur Isotopes

（Sulfur isotopic composition of sulfates and sulfides in sedimentary rocks）

Redox Sensitive Elements （Re, Os, Mo, U, etc.）

High pO2: High concentration in seawater and in reducing sediments

Low pO2: Low concentration in seawater and in sediments

anoxic

Supply due to oxidative weathering Oxidative weathering

reduction

A “Whiff” of Oxygen Before the Great Oxidation Event?

[Anbar et al. (2007) Science]

Mount McRae Shale in Western Australia 2501 ± 8 Ma (Ma = million years ago)

Proterozoic Average

Archean average

Proterozoic average A

rchean average

Mo Mo EF Re EF U EF

Oxygen Overshoot? ✓ Global deposition of sulfate evaporites between 2.22 and 2.06 Ga [Bekker and Holland (2012) EPSL]

✓ Ancient sediments from the Republic of Gabon from between about 2.15 and 2.08 Ga were deposited in well-oxygenated deep waters whereas the youngest were deposited in euxinic waters, which were globally extensive

[Canfield et al. (2013) PNAS]

[Canfield et al. (2013) PNAS]

Rise of Oxygen

Whiffs of O2

overshoot

Great Oxidation Event (GOE)

Neoproterozoic Oxidation Event (NOE)

[Modified from Lyons et al. (2014) Nature]

normal glaciation global glaciation (snowball Earth event)

PAL = present atmospheric level

3. Overview: Basic Concept of Snowball Earth Events

Discovery of Low-latitude Glacial Sediments

Neoproterozoic 650 Ma

＊Ice sheets existed at low-latitude (equator) at that time ! (ca. 650 Ma, 700 Ma, and 2300 Ma)

＊Estimates of paleolatitude for each section [Evans (2000) Am. J. Sci.]

20ºN 10ºN

20ºS

20ºS

0º

“Enigmatic” Cap Carbonate

Glacial diamictite

Formed under polar environment

Namibia

Cap carbonate

Formed under tropical to subtropical

environment

[http://www-eps.harvard.edu/people/faculty/hoffman/]

Neoproterozoic 650 Ma

Banded Iron Formation (BIF)

[Kirschvink et al. (2000) PNAS]

Neoproterozoic glaciations

4 3 2 1 0 Age (Ga; billion years ago)

Amou

nt o

f BIF

1 billion years

BIF was formed after a gap of > 1 billion years associated with glacial sediments!?

Paleoproterozoic glaciations

[http://www.snowballearth.org/]

Neoproterozoic 650 Ma

Snowball Earth Hypothesis Joseph L. Kirschvink Paul F. Hoffman

Kirschvink (1992) in The Proterozoic Biosphere Hoffman et al. (1998) Science

Ic

e Li

ne

(Lat

itude

of

Ic

e C

ap E

dge)

Globally

Ice-covered (snowball)

Partially Ice-covered

Ice-free

0

30

60

90

Level of Atmospheric CO2 (PAL) 1000 0.01 0.1 1 10 100

Climate Jump

Climate Jump

＊The Earth becomes snowball owing to decrease of greenhouse effect.

Stable Solutions for Earth’s Climate System

＊The Earth may escape from snowball when CO2 level higher than 0.7 bar.

[Tajika (2003) EPSL]

CH2O

光合成

CO2 can be built up in the atmosphere!

Weathering Degassing

Photosynthesis

Precipitation

Hydrothermal Ca2+ ← CaSiO3

Mid-oceanic ridges

degassing

mantle

plate

continent

Oceanic crust Metamor- phism

regassing The Earth can escape from the snowball climate!

©STUDIO L/STUDIO R

Latitude 0 30 60 90

-60

-40

-20

0

20

Aver

ate

Surf

ace

Tem

pera

ture

(o C)

Normal Climate

Latitude 0 30 60 90

-60 -40 -20

0 20 40 60 80

Aver

age

Surf

ace

Tem

pera

ture

(o C)

Ice-free (Hot Climate)

Climate jump

Critical condition (CO2 ~ 0.1 bar)

The Earth becomes very hot (＋60℃) just after the snowball!

Snowball

Large ice-cap instability

Climate jump Snowball

Critical condition (CO2 ~ 10ppm)

Surface Temperature Change during a Snowball Earth Event

[Tajika (2003) EPSL; Tajika (2007) EPS]

Latitude 0 30 60 90

4

3

2

1

0

Oce

an D

epth

(km

)

Oce

an D

epth

(km

)

Ts 273 T (K)

Geothermal heat flow q

ΔH

＊Ocean freezes from the surface ＊When the upper 1,000 m of the ocean freezes, heat transport becomes in an equilibrium.

The Upper 1,000 m of the Ocean Freezes

Ice

CO2

-40℃

Fe2+

O2 Degassing of CO2 from volcanos → accumulation in the atmosphere

The Earth during the Snowball

Supply of Fe2+ from hydrothermal system → accumulation in the deep ocean

CO2 ～0.7 bar

CaCO3

Chemical weathering Ca2+, HCO3

-

Surface temperature～60℃

upwelling Fe2+

O2

Fe(OH)3

Gas exchange

Formation of cap carbonate

The Earth just after the Deglaciation

Formation of BIF Ice

4. Linkage between Snowball Earth Event and Great Oxidation Event

Distribution of Glacial Sediments of 2.3 Ga

Paleolatitude 11°± 5°→ Snowball Earth event [Evans et al. (1997) Nature; Kirschvink et al. (2000) PNAS]

v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v

Post

mas

burg

Gro

up

Lucknow Fm

Mapedi Fm

Mooidraai Dolomite

Hotazel Fm

Ongeluk lava

Makganyene Diamictite

Koegas Subgroup

100m

unconformity red bed

Sulphate evaporite

drop stones

2.222±0.012 Ga 11±5°

Glacial diamictite

Kalahari Mn field

Unconformity

2.20-2.10 Ga

Fe-Mn ore deposits

Snowball Earth

Snowball Earth event (2.222Ga) and Formation of Fe-Mn Ore Deposits

[Based on Kirschvink et al. (2000) PNAS]

Kalahari Manganese Field, Hotazel Formation, South Africa

Age (million years)

4000

3000

2000

1000

0

BIF-type deposits

Pisolitic depositsKarst deposits

Black shale depositsKalahari Manganese Field

Age (million years)

80

100

60

40

20

0

Superior and Sishen-type depoAlgoma-type deposits

Oolitic and Pisolitic depositsRapitan-type deposits

...Trace in carb.

Kirschvink et al., Fig. 2

4000 3500 3000 2500 2000 1500 1000 500 0

4000 3500 3000 2500 2000 1500 1000 500 0

40 30 20 10 0 年代(億年前) Am

ount

of M

n de

posi

ts (1

06 to

n)

Kalahari Mn deposits

・ The first and largest Mn ore deposits formed just after the Paleoproterozoic Snowball Earth event ・ O2 is necessary to oxidize Mn2+ to Mn4+ → Rise of O2 just after the Paleo- proterozoic snowball Earth event !? [Kirschvink et al. (2000) PNAS]

[Gaidos et al. (1999) Science]

v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v v

Post

mas

burg

Gro

up

Lucknow Fm

Mapedi Fm

Mooidraai Dolomite

Hotazel Fm

Ongeluk lava

Makganyene Diamictite

Koegas Subgroup

100m

unconformity redbed

Sulphate evaporite

drop stones

2.222±0.012 Ga 11±5°

Glacial diamictite

Karahali Mn field

Unconformity

2.20-2.10 Ga

Ir-Mn ore deposits

Snowball Earth

Cap carbonate

Redbed (oxidative weathering)

Sulfate evaporite

Stratigraphy of the Transvaal Supergroup

[Based on Kirschvink et al. (2000) PNAS]

Silicate and

Carbonate

Organic Carbon

Atmosphere

Surface Ocean

Deep Ocean

Carbonate

Carbonate precipitation

Biological Production

Oxidative Weathering

Weathering

Degassing

Gas exchange

CO2 CH4 O2

DIC Alk PO4

3- Ca2+ O2 13C Fe Mn

Redox balance model by Goldblatt et al. (2006)

Biogeochemical Cycle Modeling

photochemistry

H2 escape

climate

1D-Ocean Biogeochemical cycle Model

[Ozaki, Tajima, and Tajika (2011) EPSL; Ozaki and Tajika (2012) EPSL]

Concentration [X]

O2

Advection Diffusion Biological pump Chemical

reaction

X：DIC, Alk, Ca2+, NO3-, NH4+, PO43-, O2, SO42-, H2S, Mn, Fe, etc.

Seafloor topography

Photosynthesis

Particulate organic matter (POM)

settling

Photic zone (depth <100 m)

burial

C P N

Phosphorus Cycle O2 hν

Upwelling

Nutrients

αCO2 + βNH4 + H2PO4- + αH2O + hν

→ (CH2O)α(NH4)β(H2PO4) + αO2 + βH+

Decomposition C,N,P

Photosynthesis

Chemical weathering

H2PO4-

Phosphorus cycle controls net primary production i.e., it controls oxygen production

Biological pump

burial

Model of Decomposition of Particulate Organic Matter (POM)

Biological Pump

Very labile G1 G2 Labile

Refractory G3

Multi-G model Particulate organic matter (POM) very labile component labile component refractory

Reduction-Oxidation (Redox) reactions aerobic oxidation (O2) denitrification (NO3

-) sulfate reduction (SO4

2-) methane production (fermentation)

oxic

reducing

Denitrification

Sulfate reduction

Aerobic respiration

Redox Reactions in the Ocean Decomposition of POM Oxidation

Nitrification

Sulfide oxidation

O2

Methane production

Methane oxidation

Anaerobic oxidation of methane

Burial fluxes of carbonate, Mn oxides,

and Fe oxides (Tmol/yr)

200 300 100 0 1

102

103

104

106

107

108

105 Tim

e after deglaciation (years)

10

Burial fluxes of CaSO4 (Tmol/yr)

0.4 0 0.8 1.2 1.6

Geological record in the Transvaal Supergroup

Mn oxides

Fe oxides

CaCO3

CaSO4

timescale of ocean mixing ○(103) years

timescale of carbonate minerals to become saturate ○(105) years

Comparison with Stratigraphy of the Transvaal Supergroup, South Africa

timescale of SO42-

to accumulate ○(107) years

Timescale for the formation of each sediment

CaSO4

CaCO3

Fe oxides

Mn oxides

Mn and Fe oxides

Sulphate (evaporite)

2.20-2.10 Ga

Carbonates

Drop stone

2.222±0.0012 Ga

snow

ball

gl

acia

tion

Redbed

unconformity

unconformity

10-6 10-4 10-2 1 pO2 (PAL)

pO2

[Harada, Tajika, and Sekine.(2014) under review]

[Sahoo et al. (2012) Nature]

Evidence for Rise of Oxygen after the Neoproterozoic Snowball Earth

635 Ma

5. Co-evolution of Earth and Life?

Bacteria Archea

Eukaryotes

Commonote Origin of life

Scale bar = 1 cm, A,B & D = C

Grypania spiralis (a megascopic eukaryotic algae)

[Han and Runnegar (1992) Science]

＊Oxygen level ＞ 0.01 PAL

2.1 Ga (billion years ago)

cell membrane (sterol)

＊Oxygen is required for biosynthesis of sterol for cell membrane ＊Mitochondria produces ATP through oxygen respiration

The Oldest Eukariote?

mitochondria chloroplast

Cam

bria

n Ed

iaca

ran

Cry

ogen

ian

Toni

an

450

500

550

600

650

700

750

800

850

0 20 40 60 80 biodiversity

order class

Age

(Ma)

Bilateral animal

Prot

osto

mia

Deu

tero

stom

ia

non-

bila

tera

l ani

mal

Ord

ovic

ian

Prot

eroz

oic

Phan

eroz

oic

Neo

prot

eroz

oic

Pale

ozoi

c Cambrian explosion

Sturtian glaciation

Marinoan glaciation

Origin of Metazoan (Animals) and Neoproterozoic Snowball Earth Events

Ediacara biota

Fossil embryos (Eumetazoa?) [Xiao et al. (1998) Nature]

Snowball

Snowball 590-630 Ma

Gaskiers glaciation

scale 1 cm

The oldest fossil of eukaryote

[Han and Runnegar (1992) Science.]

2100 Ma

Arch

ean

Prot

eroz

oic

Pha

nero

coic

0 0.5 1.0 1.5 2.0 2.5 3.0

Age

(Ga)

Evolution of life and Snowball

The oldest fossils of metazoan [Xiao et al. (1998) Nature.] 590-630 Ma

Late Cenozoic

Late Carboniferous Late Ordvician Gaskiers Marinoan Sturtian

Huronian

Pongola?

Rise of Oxygen and Evolution of Life

Whiff of O2?

overshoot?

Great Oxygenation Event (GOE)

Neoproterozoic Oxygenation Event (NOE)

[Modified from Lyons et al. (2014) Nature]

Ice age

snowball Earth event

Eukarya Animal

Summary 1. Deglaciation of the snowball Earth should provide strong

perturbation to the biogeochemical cycle system, which promotes supply of large amounts of phosphate to the oceans to bloom cyanobacteria and to produce large amount of oxygen, resulting in an irreversible change of atmospheric oxygen level.

2. Long-lasting overshoot of oxygen level may be caused by production of large amount of oxygen excess, and then, a gradual consumption of excess oxygen by reductant supplied from the Earth’s interior.

3. Sedimentary sequence of the Transvaal Supergroup can be explained by different timescales for the minerals to precipitate.

4. Emergence of eukaryote and animals might have been as a result of the rise of oxygen triggered by the snowball Earth events both in the Paleoproterozoic and the Neoproterozoic.