When and how did the cores of terrestrial planets form?

Slides:



Advertisements
Similar presentations
Differentiation of the Earth Differentiation is the process by which random chunks of primordial matter were transformed into a body whose interior is.
Advertisements

The nebular hypothesis
Mantle composition 1800s meteorites contain similar minerals to terrestrial rocks Hypothesis that meteorites come from asteroid belt and originate from.
History of “primordial” Pb Meteorite samples Chondrite – a primitive, undifferentiated meteorite CI refers to a particular class of carbonaceous chondrite.
Anne M. Hofmeister and Robert E. Criss
Formation of our Moon: The Giant Impact Hypothesis Michelle Kirchoff Southwest Research Institute Center for Lunar Origin and Evolution.
Mercury’s origin and evolution:- Likely evidence from surface composition David A Rothery 1, J Carpenter 2, G Fraser 2 & the MIXS team 1 Dept of Earth.
Other clues to the formation of the Solar System Inner planets are small and dense Outer planets are large and have low density Satellites of the outer.
Internal structure of planets Internal structures of planets (not at scale). The three sub-families on the left are part of the terrestrial family. Giant.
The Late Veneer: constraints on composition, mass, and mixing timescales “Post-AGU” Divya Allupeddinti Beth-Ann Bell Lea Bello Ana Cernok Nilotpal Ghosh.
The Universe. The Milky Way Galaxy, one of billions of other galaxies in the universe, contains about 400 billion stars and countless other objects. Why.
Magma Oceans, core formation and the differentiation of the Earth B.J. Wood.
PSRDPSRD presents Compositional Balancing Before Moon Formation A striking feature of the Earth and Moon.
TERRESTRIAL PLANET FORMATION & THE FORMATION OF A WATER-RICH EARTH
Emil Johann Wiechert In 1897, Earth’s 1 st order structure -- silicate shell surrounding metal core.
Evolution of the Solar System Matt Rogers AT350 9 September 2003.
1 Chapter 2 Creation of Oceans. 2 Supporting Evidence for the Big Bang Edwin Hubble discovered spreading of galaxies. Cosmic background radiation (the.
Ge/Ay133 What can meteorites tell us about the early S.S.?
1 Lecture #02 - Earth History. 2 The Fine Structure of The Universe : The Elements Elements are a basic building block of molecules, and only 92 natural.
Ge/Ay133 When and how did the cores of terrestrial planets form?
Chemistry of the mantle. Physical processes (subduction, convection) affect the chemistry of the mantle. Chemical processes occur mainly through melting.
Introduction to Deep Time Physics Perspective Dave Stevenson Caltech CIDER, July 2012.
Open problems in terrestrial planet formation
The Diversity of Extrasolar Terrestrial Planets J. Bond, D. Lauretta & D. O’Brien IAU Symposium th August 2009.
An Artist’s Impression The young Sun gas/dust nebula solid planetesimals.
Geology for Engineers Planet Earth. Organisation 30 Lectures: Monday, Tuesday, Wednesday 10-11am, M17 4 Practicals: Tuesday afternoon, Main Lab Geology.
The geological history of the Moon. The last blast-off from the Moon =channel.
The Moon Formation. Lunar Facts The moon ended its formation period approximately 4 billion years ago. After the period of formation, the surface of the.
Lecture 3 – Planetary Migration, the Moon, and the Late Heavy Bombardment Abiol 574.
Tuesday October 9, 2012 (Our Solar System – Evolution of the Planets; Mercury & Venus; Video Segment – Journey to the Edge of the Universe)
Carbon in the Earth’s core Yingwei Fei Geophysical Laboratory Carnegie Institution of Washington.
The Chemistry of Extrasolar Planetary Systems J. Bond, D. O’Brien and D. Lauretta.
1 Ch. 23: “Touring Our Solar System” 23.1: “The Solar System”
How do “Habitable” Planets Form? Sean Raymond University of Washington Collaborators: Tom Quinn (Washington) Jonathan Lunine (Arizona)
Models of Core Formation in Terrestrial Planets Dave Rubie (Bayerisches Geoinstitut, Bayreuth, Germany) CIDER Summer Program 2012 Santa Barbara Acknowledgements:
Planet Building Part 3 Growth of Protoplanets. Starter Hubble images WKn7k&list=PLiuUQ9asub3Ta8mqP5LNiOhOygRzue8k.
Asteroids (in space) and Meteorites (once they have entered the atmosphere) Meteorites hit the atmosphere with speeds from 12 to 72 km/s. Earth’s orbital.
The Diversity of Extrasolar Terrestrial Planets J. Carter-Bond, D. O’Brien & C. Tinney RSAA Colloquium 12 April 2012.
SIO224 Internal Constitution of the Earth Fundamental problem: the nature of mass and heat transfer in the mantle and the evolution of the Earth.
WATER ON EARTH Alessandro Morbidelli CNRS, Observatoire de la Cote d’Azur, Nice.
Origin of the Moon 2 September 2015.
Our Solar System and Its Origin. 6.4 The Formation of Planets Our Goals for Learning Why are there two types of planets? Where did asteroids and comets.
Geologic History. “Big Bang” about 13.7 billion years ago All matter in the universe created made entirely of Hydrogen and Helium ~13 b.y.a. oldest galaxies.
Magma Oceans in the Inner Solar System Linda T. Elkins-Tanton.
Importance of tighter constraints on U and Th abundances of the whole Earth by Geo-neutrino determinations Shun’ichi Nakai ERI, The University of Tokyo.
The Chemistry of Extrasolar Planetary Systems Jade Bond PhD Defense 31 st October 2008.
Nucleosynthetic processes: Fusion: Hydrogen Helium Carbon Oxygen After Fe, neutron addition takes place (rapid and slow processes)
Fundamental Concepts GLY 4310 Spring, 2016
Slide 1 The Earth is differentiated How and When did this occur? Two Sets of Constraints: Physical Mechanisms and Chemical Signatures.
Chemistry During Accretion of the Earth Laura Schaefer and Bruce Fegley Planetary Chemistry Laboratory McDonnell Center for the Space Sciences Department.
Jeff TaylorAges, Mantle Sources, Differentiation1 SNC Ages, Mantle Sources, and the Differentiation of Mars Crystallization ages of Martian meteorites.
Signatures of Early Earth Differentiation in the Deep Mantle?
All images and ideas from
Notes: Earth/Moon Formation 3/11. 1.Explain the three sources of heat that contributed to the high temperature of the newly formed Earth. (p. 688). The.
Outstanding issues(think, research topics for weeks 3 & 4) the composition of the lower mantle (major elements) proportion of ferro-periclase (0% to 20%)
Creech et al. Late accretion history of the terrestrial planets inferred from platinum stable isotopes Figure 3 Model of the effect of addition of chondritic.
Formation and Composition of Earth’s Core Beyond the Current Paradigms
Theories of Formation for the Moon
Origin of the Moon 22 September 2017.
Fundamental Concepts GLY 4310 Spring, 2013
Savage et al. Copper isotope evidence for large-scale sulphide fractionation during Earth’s differentiation Figure 2 Schematic evolution of Cu concentration.
SIO224 Internal Constitution of the Earth
Zinc Isotopes Provide Clues to Volatile Loss During Moon Formation
Making and Differentiating Planets
When and how did the cores of terrestrial planets form?
Compositional Balancing Before Moon Formation
SATISH PRADHAN DNYANASADHANA COLLEGE,THANE
Volatile Elements Test Models for the Origin of the Moon
Stochastic Late Accretion on the Earth, Moon and Mars
The Moon.
Presentation transcript:

When and how did the cores of terrestrial planets form? Ge/Ay133

Two end member hypotheses for core formation: Estimated core sizes of the terrestrial planets.

Two end member hypotheses for core formation: Q: Why is heterogeneous accretion unlikely? A: In a gas of solar composition, silicates and iron metal (it IS a reducing environment!) condense over similar ranges in T,P.

Two end member hypotheses for core formation: Estimated core sizes of the terrestrial planets. For homogeneous accretion, when does the onset of differentiation occur?

How might we distinguish these, and their timing? Step 1: Know your geochemical affinities!

Highly siderophile elements in the mantle: Late veneer…

…or high pressure chemistry? Mixing?

Step 2: Know how to measure isotopes very well!

Absolute Pb-Pb dating error bars getting down to ~1 Myr!

182Hf 182W 9

Once you have ages, can look for short-lived excesses: Hf/W ideal, since Hf is lithophilic, while W is a siderophile & t1/2 = 9 Myr.

Once you have ages, can look for short-lived excesses: Hf/Wdata from meteorites. 180Hf/184W

Ages highly model dependent! More in a bit… Kleine et al. (2002) Yin et al. (2002) Models here assume complete equilibration…

Size dependence? What about earth-moon?

Geochemical partitioning is sensitive to the depth at which silicates last “see” Fe/Ni metal. The atmosphere is also strongly affected by core formation, and its timing.

Need to know how large an incoming differentiated planetesimal can be and still equilibrate… Answer seems to be pretty small! Means that full equilibration is unlikely…

Equilibrium Gas Abundances in Silicate Magmas SiO2 + 2Fe3O4 → 3Fe2SiO4 + 02 SiO2 + 2Fe + O2 → Fe2SiO4 The atmosphere is also strongly affected by core formation, and its timing.

Equilibrium Gas Abundances in Silicate Magmas SiO2 + 2Fe3O4 → 3Fe2SiO4 + 02 Quartz Fayalite Magnetite (QFM) SiO2 + 2Fe + O2 → Fe2SiO4 Quartz Iron Fayalite (QFI) Might the exogenous delivery of organics to the early Earth been important?

Giant impacts & the Earth-Moon System: R. Canup 2004, Icarus 168, 433 (and the slides that follow) 1. Temperature behavior

Where does material go, & what is its composition?

A `typical’ Moon forming event & simulation summary:

Temperature evolution:

Where does the iron/silicate go?