Transcript Linking Asteroids and Meteorites through Reflectance

Physical Geology Laboratory
Tuesday
Tom Burbine
[email protected]
Course
• Course Website:
– http://blogs.umass.edu/tburbine/
• Textbook:
– Laboratory Manual in Physical Geology, 8th Edition (2009)
Busch
• You also will need a calculator that you will bring to class.
Virtual office hours
• You can IM me at tomburbine on AOL
• Student: and who are u? lol
Student: u gotta answer cuz i asked first both times
tomburbine: why r u Iming me
Student: cuz u added my sn for some reason so i wana know why
tomburbine: sn?
Student: screen name?
Student: lol
tomburbine: no I didnt
Student: ok..
tomburbine: do u live in massachusetts?
Student: do u?
tomburbine: do u live in cambridge?
Student: no
tomburbine: is it snowing?
Student: yea
tomburbine: do u have a xnga?
Student: no joke who the f**k are ya?
Student: yes i do live in MA
tomburbine: i never heard of u until u Imed me
Student: then how the h**l did u know i lived in MA?
• Student: and yes i do go to umass
tomburbine: r u in astronomy 100
Student: how do u know all this?
tomburbine: because I am the professor
Student: OHHHHH OOOPS!
tomburbine: i think u must have added me
Student: omg lol
tomburbine: and then forgot who I was
Student: ya i did
Student: sorry for all that
tomburbine: my name is my screen name
tomburbine: seem familar now
Student: didnt mean to use language but it happened
tomburbine: no problem
tomburbine: funny
Student: heh
tomburbine: i actually dont know who u r
Student: good thing we got an exta 2 days for the hw
tomburbine: yes
tomburbine: u can Im me anytime
tomburbine: and
Student: ill tell ya if u promiss not to fail me
tomburbine: I cant add my name to ur aim
tomburbine: only u can
tomburbine: i am fine not knowing
Student: ok
Student: well i have to go ill cya on thursday. take care
tomburbine: bye!
Plate Tectonics
• Plate Tectonics describes the large scale motions
of Earth's lithosphere
Continental Drift Hypothesis
• Alfred Wegener (1915) thought that all continents
were part of a single supercontinent called Pangea
Pangea
• Pangea - One large supercontinent
http://geology.csupomona.edu/drjessey/class/Gsc101/pangea.gif
Principles of Plate Tectonics
1. The surface of the Earth is
composed of lithospheric plates
that are in constant motion.
2. The plates move in response to
plastic flow in the athenosphere.
3. Motion in the asthenosphere is
caused by convection driven by
the Earth’s internal heat.
4. The internal heat comes from
radioactive decay and the latent
heat from the Earth’s formation.
Plate Tectonics
• Earth has a thin rigid lithosphere that is underlain
by a plastic asthenosphere
• Seafloor crust is created along mid-ocean ridges
where magma upwells from the mantle
• Ocean basins are generally younger than
continents
• Seaflloor spreads until it encounters a trench and
descends back into the mantle
• Rocks can deform and flow
• Easier for rock to deform and flow when it is
warmer
Heating of Planet
Lithosphere
• Lithosphere is a planet’s outer layer of cool and
relatively rigid rock
• Asthenosphere is the region in the upper mantle
characterized by low-density, semiplastic (or
partially molten) rock material chemically similar
to the overlying lithosphere
Three Types of Plate Tectonic Boundaries
• Divergent – plates move apart, space is filled with
molten magma
• Convergent – plates collide
• Transform – plates slide horizontally past each other
Divergent plate boundary
Convergent Plate Boundary
Transform Boundaries
Magma
• Magma – a mixture of molten rock, volatiles, and
solids
• Lava is magma that erupts on the surface
Melting Point
• Melting point – temperature that crystals of a
given mineral melt
• All minerals have different melting points
• Partial melting – part of a rock melts before
another rock
Geothermal Gradient
• Increasing temperature with depth
Pressure
• Pressure is force per unit area
• Pressure increases as you go deeper in Earth
because of the weight of the surrounding rock
Pressure
• Raising the confining pressure increases the
melting point of the rock
• Lowering the confining pressure lowers the
melting point of a rock
P-T (pressure-temperature) diagram
Hot Spots
Any Questions?