Metamorphic + Time

form when pre-existing rocks are exposed to increased pressure and/or temperature, causing solid-state recrystallization

the rock before

Causes of Metamorphism (2)

Consequences of Metamorphism (5)

same mineral, new size and shape

same composition, new mineral

growth of new mineral (chem and structure)

minerals smooshed together. Dissolution occurs at grain to grain contacts and new growth occurs in locations with less pressure

changing shape without breaking under high pressure and temperature

large crystal that grows within a finer-grained matrix during metamorphism

squeezing a material

moving part of a material sideways relative to another

metamorphism with high pressure but relative low temperature that happens in subduction zones; happens over a large region

metamorphism where heat is transferred from melt to surrounding rock

metamorphism where, with depth, both pressure and temperature increase (but not extreme)

metamorphism with intense heat and pressure from shock wave pulse

planar rock fabric

the present is the key to the past

youngest on top

sediment layers are fairly horizontal when deposited and can be altered by deformation

sediment generally deposited in continuous sheets. If later cut, you can assume once continuous

igneous intrusive must be younger than the rock it cuts across

heat transferred from igneous melt to surrounding rock. Evidence that surrounding rock existed prior to igneous rock

rock containing inclusion is younger than the inclusion

fossils that can be used for relative dating

who realized that strata occurred in a predictable pattern and he could use fossils to trace rock layers. Made the first detailed nationwide geological map

beds tilted and eroded prior to deposition of new horizontal bed on top. Forms between two strata not parallel to each other

process by which the nucleus of an unstable atom loses energy by emitting radiation

igneous or metamorphic rock surface eroded and then sedimentary rock deposited on top. Forms between older metamorphic or igneous rocks and younger sediment strata deposited on top of them

erosional surface between sedimentary rock layers where the older rock layer has been eroded but not tilted
Forms between parallel strata

Radiation can be one or more of the following (4)

same element (number of protons) but different number of neutrons

time required for one-half of parent to be converted into daughter

Hierarchy of Geological Time