Historical Geology Chapter Vocabulary
Chapter 6-Sedimentary Rocks
based upon Historical Geology-by Wicander and Monroe


CHEMICAL SEDIMENTARY ROCKS
     limestone
     dolomite
     gypsum
     salt

BIOLOGICAL SEDIMENTARY ROCKS
     coal

CLASTIC (DETRITAL) SEDIMENTARY ROCKS
based on grain size, shape (rounding), and sorting (variation in size)
     conglomerate
     breccia
     sandstone
     siltstone
     shale

SEDIMENTARY STRUCTURES
formed while sediments are still soft
     bedding
     graded bedding (coarse at bottom, fine at top)
     cross-bedding (tipped layers are eroded, new layers on top of eroded surface)
     ripple marks (symmetric vs. asymmetric)
     mud cracks
     trace fossils (footprints and burrows) (bioturbation)
these are useful in determining if layers are rightside up.

Fossils
Question: Were the fossils deposited where the life forms died or were they transported?
Reworked fossils are also a problem (eroded from an older formation).

CONTINENTAL ENVIRONMENTS
     fluvial (river deposits): braided streams, meandering rivers
     aeolian (deserts, windblown): sand dunes, alluvial fans, evaporites (page 117)
     pluvial (lakes): varves
     glacial (glaciers):  glacial till, glacial erratics, loess (outwash)

TRANSITIONAL ENVIRONMENTS
     deltas
     tidal flats
     barrier islands (herringbone cross-beds- figure 6.16)

MARINE ENVIRONMENTS
     continental shelf
     continental slope and continental rise
     limestone deposits (micrites-fine grained)

Paleogeographic maps (Figure 6.22)