Venue: Geology Section, IGN, University of Copenhagen
Address: GeoCenter, Øster Voldgade 10, Copenhagen 1350, Denmark
Organizers: Hans Thybo, [email protected]; Irina Artemieva, [email protected]
PostDoc/PhD contacts during the meeting:
Matija Herceg, +45-4280 5808, Yulia Cherepanova +45-5312 4833,
Olga Barantseva +45-9193 3013, Helene Kraft
How to get there?
GeoCenter is labelled “Institute”
Danish national search-engine with maps (incl. 3D city views): krak.dk
Faculty for Natural Sciences in Copenhagen - Elite course
" How to interpret geophysical observations
in terms of composition and dynamics of Earth (and other planets)"
S. Karato (Yale University, USA) and A. Tommasi (Geosciences Montpellier, FR)
14-18 June, 2014
The Goal
The goal is to provide you with the basic concepts that play an important role in
interpreting the geophysical observations including seismological and electromagnetic
induction observations in terms of composition and dynamics of Earth and other planets.
Geophysicists infer elastic (+ anelastic) properties and electrical conductivity through remote
sensing. Interpretations of these observations are usually highly non-unique. Integration of
various observations with a sound basis on the physics and chemistry of materials is essential,
but challenging. You will learn (i) materials science fundamentals needed in the interpretation
of these observations and (ii) an interdisciplinary (integrated) approach allowing for
constraining the interpretation of these data in terms of composition and deformation of the
Earth.
Applications will include:
(1) the study of mantle deformation based on seismic anisotropy observations,
(2) the interpretation of the geophysical observations of the lithosphere-asthenosphere
boundary and the “mid-lithosphere discontinuity” in the upper mantle, of the mantle transition
zone, the D” layer, and structure of the Moon, and
(3) the analysis of the role of mechanical anisotropy in plate tectonics.
The materials science basics include:
(1) a general introduction to elasticity and anelasticity,
(2) elastic properties of a crystal (Birth’s law, thermal expansion, Grüneisen parameter),
(3) defects and anelasticity,
(4) defects and electrical conductivity of minerals,
(5) the anisotropy of physical properties,
(6) the upscaling from crystal to rock and larger scale physical properties,
(7) physics and chemistry of partial melting (melt fraction, melt geometry (dihedral angle),
compaction).
Day-by-day program, Auditorium C, GeoCenter
14 June (Sat.) – Deformation and anisotropy of physical properties
by Andréa Tommasi
8.45 – meeting at the main entrance to GeoCenter, Øster Voldgade 10
(because of weekend, the building will be locked)
Block 1
9h-10h15: Introduction to anisotropy of physical properties.
Thermal diffusivity anisotropy of olivine as an example.
Causes of anisotropy in rocks: oriented fractures, compositional layering,
preferred orientation of crystals.
Tea/coffee break – room next to aud. C
10h30-12h: How and why do crystal preferred orientations form.
Principles of viscoplastic deformation of crystalline materials (dislocation
glide, dislocation creep, diffusion creep, grain boundary migration and
sliding).
Introduction of the discussion topic of 17 June: Olivine CPO development
by diffusion creep
Lunch – Røde Stue (the “Red Room”), organized for everyone: pizzas, fruits, soft drinks
Block 2
13h30-15h30: From single-crystal anisotropy to rock-scale anisotropy.
How is the single crystal data determined (experiments, ab initio
modelling)?
How are CPO measured?
Principles and methods for the analysis of CPO data.
How is the anisotropy of a rock calculated.
Tea/coffee break – room next to aud. C
16h-18h: Seminar by Barbara Romanowicz (Univ. Berkeley & Collège de France):
Evidence for seismic anisotropy in the Earth's mantle at global and
continental scales
18h30 – 22h00: Dinner for all participants (meat/fish/vegetarian buffet; GeoCenter,
Røde Stue (the “Red Room”)
15 June (Sun.) - Fundamentals of the interpretation of geophysical observations
by Shun Karato
8.45 – meeting at the main entrance to GeoCenter, Øster Voldgade 10
(because of weekend, the building will be locked)
Block 1
9h-10h15 : Introduction
(overview of mechanical behavior of condensed matter,
overview of phase transformations in Earth,
chemical stratification)
Tea/coffee break – room next to aud. C
10h30-12h : Elasticity
(Birch’s law, anharmonicity, thermal expansion, Grüneisen parameter)
Lunch – GeoCenter, Røde Stue (the “Red Room”), organized for everyone: sandwiches, fruits,
soft drinks
Block 2
13h30-14h45 : Defects and non-elastic properties I
15h-16h: Defects and non-elastic properties II
Tea/coffee break – room next to aud. C
16h-18h : Seminar by Lev Vinnik
16 June (Mon.) - Fundamentals of the interpretation of geophysical observations
by Shun Karato
Block 1
9 h-10h15 : Defects and electrical conductivity of minerals
Tea/coffee break – room next to aud. C
10h30-12h : Influence of partial melting
Lunch – GeoCenter canteen, ground level, entrance from Rotonda, self-service, costs 25-35 dkk
Block 2
13h30-14h45 : Some applications : lithosphere-asthenosphere, transition zone, D’’ layer
Tea/coffee break – room next to aud. C
15h-17h: Student presentations/discussions
17 June (Tue.) – Using seismic anisotropy to map mantle deformation
by Andréa Tommasi
Block 1
9h-10h15: Seismological measurements of anisotropy.
Body waves : Pn anisotropy and SKS splitting.
Surface waves polarization anisotropy (Love/Rayleigh discrepancy).
Rayleigh waves azimuthal anisotropy.
How to interpret these seismological measurements in terms of upper
mantle deformation.
Tea/coffee break – room next to aud. C
10h30-12h: Seismic anisotropy in the upper mantle: Observations and interpretation for
different geodynamical settings.
Forward models of mantle flow and seismic anisotropy.
Lunch – GeoCenter canteen, ground level of Rotonda, self-service, costs ca. 25-35 dkk
Block 2
13h30-15h15: Practical: Predicting the seismic anisotropy in a continental rift.
Tea/coffee break – room next to aud. C
15h30-16h30: Which are the processes that may destroy or modify a CPO?
Effects of temperature, stress, pressure, water, and melt on deformation and
CPO evolution.
Examples of olivine and quartz (temperature control on slip systems'
activation).
CPO evolution during static recrystallisation and melt percolation.
Tea/coffee break – room next to aud. C
17h-18h: Discussion: Crystal Preferred Orientation development by diffusion creep
Suggested lectures: Wheeler, J. (2009). The preservation of seismic anisotropy in the Earth's mantle during diffusion creep.
Geophysical Journal International, 178(3), 1723-1732.
Miyazaki, T., Sueyoshi, K., & Hiraga, T. (2013). Olivine crystals align during diffusion creep of Earth/'s
upper mantle. Nature, 502(7471), 321-326.
Sundberg, M., and R. F. Cooper (2008), Crystallographic preferred orientation produced by diffusional creep
of harzburgite: Effects of chemical interactions among phases during plastic flow, J. Geophys. Res.,113,
B12208, doi:10.1029/2008JB005618
Walker, A.N., Rutter, E.H., Brodie, K.H., 1991. Experimental study of grain-size sensitive flow of synthetic,
hot-pressed calcite rocks, in: Knipe, R.J., Rutter, E.H. (Eds.), Deformation Mechanisms, Rheology and
Tectonics. The Geological Society, London, pp. 259-284
Pieri, M., Kunze, K., Burlini, L., Stretton, I., Olgaard, D. L., Burg, J. P., & Wenk, H. R. (2001). Texture
development of calcite by deformation and dynamic recrystallization at 1000K during torsion
experiments of marble to large strains. Tectonophysics, 330(1), 119-140.
Heidelbach, F., Stretton, I., Langenhorst, F., & Mackwell, S. (2003). Fabric evolution during high shear
strain deformation of magnesiowüstite (Mg0. 8Fe0. 2O). Journal of Geophysical Research: Solid Earth
(1978–2012), 108(B3).
18 June (Wed.) – More anisotropy … by Andréa Tommasi
Block 1
9h-10h15: Mechanical anisotropy.
Recent experimental data.
Predictions from viscoplastic self-consistent models.
Role of mechanical anisotropy on the reactivation of preexisting structures in
plate tectonics
Tea/coffee break – room next to aud. C
10h30-12h: Melts and anisotropy: observations in natural systems, petrophysical models
& seismological observations.
Lunch – GeoCenter canteen, ground level of Rotonda, self-service, costs ca. 25-35 dkk
Block 2
13h30-16h30: Debate with participation of ALL students:
- May water explain seismic discontinuities, anisotropy, and electrical
conductivity in the upper mantle? Or do we need partial melt?
Round-up and Farewell drink:
17h00-18h00: Røde Stue or Geophysical Lab
Recommended accommodation for your stay, low price category:
Hotel Løven: http://www.loevenhotel.dk/eng.html
Hotel CabInn: https://www.cabinn.com/en/
Hotel Wakeup Copenhagen: https://www.wakeupcopenhagen.com/booking
/index.php?client=arpHansenWakeup&lang=en
The above mentioned hotels are all located in central Copenhagen, about 15 minutes
away from our Department by bus or metro.
If you prefer to stay within walking distance of our department, Hotel Østerport is very
close, but the price is ca. 1000 kr per night: http://hotelosterport.dk/en/