Exam-II Review (2014) (15% of total grade)
Geochem/Habitable Planet EESC 3101 • (Lectures 9-15)
Format:
Short answer, sketches, short calculations, interpreting plots
Bring calculator, pencils/pen, may use periodic table and nuclide chart in room
Closed book, based on lecture material and problem sets - key topics outlined below:
Mineralogy and Petrology basics
What are minerals (general formulas), rocks?, Mineralogy of the mantle and crust
Major building blocks, SiO42--Tetrahedra
Melting temperatures (crust, mantle)
making of basalts and granites
Melting of the mantle
concept of solidus and liquidus, partial melt
Fractionation of elements: Partition coefficient and bulk partition coefficient
Compatible and incompatible elements
Batch (equilibrium) partial melting
Decompression melting, flux melting (freezing point depression), melting by raising temperature
Melting at mid-ocean ridges: melting triangle, mantle temperature
Thermodynamic concepts (Adiabatic decompression, superheat, heat of fusion/crystallization)
Plate tectonics
Composition, physical parameters, Earth structure (seismic velocity, density)
Isostasy, bimodal surface elevation
crust formation, recycling of crust, convection
mid-ocean ridges (water depth, crustal thickness, depleted MORB mantle – two stage melting)
subduction zones (thermal regime, alteration of oceanic plate, sediment melt)
Melting at hotspots vs. mid-ocean ridges
Geochemical behavior and fingerprints
Fluid mobile elements (large ions, small charge) versus immobile (small ions, large charge)
Proxy elements for melting processes (e.g. Na, Ti)
Goldschmidt’s Elements: siderophile, lithophile, chalcophile, atmophile
Rare earth elements (REE), Lanthanide contraction
REE pattern (normalization), concave vs. convex, MORB vs. Arc vs. OIB vs. Continental Crust
Light, middle, heavy, REE, minerals of interest: Clinopyroxene, plagioclase, garnet
Continental crust
Making new crust (Arcs vs. LIPs, linear vs. steady-state vs. episodic)
Juvenile vs. recycled crust (Sm-Nd isotopes and 143Nd/144Nd vs. 87Sr/86Sr)
Nd evolution diagram, Model ages, Chondritic uniform reservoir (CHUR), Supercontinents
Analytical concepts
Precision vs. Accuracy, %-ppm-ppb-ppt, mass spectrometry, calibration curves