Quiz 4

Consists of the crust and upper mantle

The ductile (flexible) portion of the upper mantle

Move across the asthenosphere

Postulated the theory of continental drift

• Continents fit like a puzzle • Similar fossils on different continents • Geological structures • Paleomagnetism

Oceanic crust –>

Continental crust –>

Oceanic crust –>

• builds mid-ocean ridges, new crusts

• builds ocean basin

• moderate to massive earthquakes • horizontal movement of two plates in opposite directions • high friction, high tension Ex. San Andreas fault, CA

The oceanic crust usually sinks into the mantle beneath lighter continental crust

Oceanic crust weighs more and is denser than continental crust

• gaps in geologic record A. Disconformity B. Angular unconformity C. Nonconformity

| | | | | v v v v v 3 limestone | 2 | sequence of events 1 sandstone V Undisturbed layer

Rank of age of the rock layers from oldest to youngest 1>2>3 Oldest–>youngest

Inclusions: physical evidence in the disturbed rock layer Ex. Of disturbance includes erosion, uplifting by subterranean forces, folding, faulting, etc… REMEMBER- Inclusions are older than the rock that contains them

Bottom line - when an intrusion or fault cuts them an existing feature, it is the youngest event

If we know the kind of fossil, preserved in the rock layers, the relative age of the rock can be determined

Numerical age - use radiometric dating technique • half life: the amount of the time it takes for half the parent radioactive element to decay to a daughter period

Distance between two successive crests

Time between two successive crests

Highest point of a wave

Lowest point on a wave