Earth Sciences 9
EARTH HISTORY and GLOBAL CHANGE
Course description: The study of Earths history provides a rich account of many
exciting and dramatic changes in environments, climate and life that have taken place
through time. This course prov
Homework 6 Rock Types: Igneous
1) Be familiar with the role certain minerals such as gold and mercury
have played in the history of California.
Gold - made it desirable to travel to california, land was extremely available
Homework 8 Sedimentary Rocks
1) What is the definition of a clastic sedimentary rock? Think of some
examples you saw in section or lab
Weathering and erosion of rocks exposed at surface, compaction of sedimentary
1) How old is the oldest ocean crust and how does that compare with the
age of the continental crust?
ocean crust - 200 million years old; younger because of subduction
continental crust - 2 to 4 billion years old; not sub
11) What are typical rates of plate motions?
The average movement of plates vary depending on their location. Exact
measurement is unclear since it varies with different publications but estimates
are usually given at a ra
6) Why are sedimentary rocks importantwhat do they tell us, what they
do for us?
Tells us the history of the Earth and its surface conditions, contains fossils.
Important economically for gas, oil, coal.
Hydrologically - E
1) What is the difference between a basalt and a gabbro? An andesite and
a diorite? A granite and a rhyolite?
basalt and gabbro - gabbro has larger grains than basalt
andesite and a diorite - diorite = intrustive, andesite
1) How are external physical properties (crystal form, cleavage, hardness,
density) controlled by atomic structure?
Cleavage - brown and blue atoms into flat sheets (Strong bond)
crystal - breaks through the lattice in any
Homework 4: Minerals
1) What is the definition of a mineral?
A chemical compound, a solid inorganic substance of natural occurrence
2) What is the difference between a rock and a mineral.
A mineral is a chemical compound while a rock
Metamorphic Rocks Homework 10
1) What is the definition of a metamorphic rock?
Rock that is altered by heat and pressure
2) What is the difference between regional and contact metamorphism?
How might rocks subjected to these two type
1) How is the global pattern of earthquake and volcano locations related
to plate tectonics?
Plates make up earth's crust above magma layer. Tectonic plates make up the
less-than-firm crust of the earth. These plates float