Craton quiz

types of rocks in continental shield

igneous, metamorphic

type of rocks covering continental platform

sedimentary

glacial features

deposits from continental ice sheet, lakes, erratics

where is continental shield

north, mostly canada

where is the continental platform

middle south, also uplifted colorado plateau

foreland structures

deformed craton, formed with compressional forces

where is coastal plain?

southeast coast

how were platform stratas deposited

warm, tropical seas

how were caves in np formed

limestone from warm, shallow seas

domes and arches

places where rocks have been folded upward, erosion exposes older rocks

basins

rocks have been folded downward, erosion exposes younger rocks

how do caves form

groundwater dissolves limestone and dolomite, leaving floors and ceilings of sandstone and shale

when were platform strata deposited

late cretaceous, 90 mya

features of colorado plateau

erosional features, stratigraphic layers revealing history

features of foreland structures

basement uplifts, fold and thrust belts, foreland basins

permian reef complex

panthalassa sea during permian after formation of pangea, tropical climate, delaware basin in nm, uplifted by normal faulting

stratigraphy of reef complex

back reef, reef, fore reef, basin (back to front)

development of cross bedding

wind and water pick up sand form one side of dune, deposit on other side

stair step erosion

soft rocks gentle slope, hard rocks steep slope

development of foreland structures

normal angle subduction

what shape valley do rivers cut

v

what shape valley do glaciers cut

u

morraine

rock piles deposited by glaciers

laramide uplift

reverse fault, compressional structures, erosion removes sedimentary layers and exposes crystalline basement rocks

examples of laramide uplift

rocky mountain national park, flat irons, mount rushmore, dinosaur nm