Initial Publication Date: September 6, 2006

Knowledge Survey Questions - Historical Geology

Compare and contrast igneous, metamorphic, and sedimentary rocks.
Describe the basic properties of sedimentary rocks that are most useful to the geologist charged with reconstructing ancient depositional environments?
Compare and contrast the basic properties and relative ages of oceanic and continental crust.
Explain sources of heat energy on Earth, and their role in plate tectonic processes.
Draw a diagram of both the chemical and rheological boundaries of Earth, and their thicknesses. Which designation is more important for plate tectonics?
What is the age of the Earth, and how do we know this?
What are the requirements for life on a planet, and what evidence suggests it is difficult for complex life to form?
Why did complex life in the oceans appear at least 150 million years before complex life on land?

Briefly describe world geography at the end of the Paleozoic.
Provide evidence of evolution.
Describe/define key events in the history of life on Earth.
Present evidence for the cause of mass extinction at the K/T boundary.
You have in front of you three intrusive igneous rocks, each with variable amounts of silica. Can you identify/name each rock, and compare tectonic settings in which we expect to find each?

How would you order events in Earth history / build a relative timescale?
Describe the significance and limitations of uniformitarianism.
Describe how mountains form.
Explain how geologists calibrate (add actual numbers to) the geological time scale.
Describe the evidence for the K/T (Cretaceous - Tertiary) extinction event.
What evidence supports the timing of the impact that formed our moon?
What is punctuated equilibrium, and how is this theory supported by fossil evidence?
What have been the major causes for mass extinctions in Earth history?
What would be the age of a zircon crystal if it contains 16 million atoms of 238U and 8.0 million atoms of 206Pb? The crystal had an initial quantity of 6.0 million atoms of 206Pb. Assume the system is closed and that T1/2 is 4.47 x 10^9 years.

Discuss/describe the feedbacks/interrelations among the lithosphere, atmosphere, hydrosphere, and biosphere?
Design a study to determine whether the Earth is tectonically active (what is evidence for Plate Tectonics?).
Design a study that uses the basic properties of sedimentary rocks and/or fossils to infer aspects of ancient climates?
Formulate a plan to use sedimentary rocks and/or fossils to reconstruct changes in sea level.
Explain how tectonic processes control Earth's climate.
Oxygen isotope ratios are arguably the most important tool we have for deducing climate history of the Cenozoic. Explain how this method works, and what information we can glean from examining these records.

Evaluate the significance of unconformities in relation to geologic time.
Predict earth's climate 100 million years from now, and explain what the major controls are expected to be.