

Unconformities (hiatus)
disconformity (rock layers are parallel, but big gap in time...erosion or
non-deposition)
nonconformity (sedimentary rocks on top of metamorphic or igneous rocks)
angular unconformity (sets of layers oriented at different orientations)
Lateral Relationships-Facies
facies = environment
intertonguing, pinchouts
sedimentary facies = sedimentary environment
Marine Transgressions and Regressions
marine transgression-ocean moves across the land (coarse materials at bottom of
sequence)
marine regression-shoreline moves away from land (fine materials at bottom of
sequence)
Walther's law: coarse materials are closer to shore; fine materials are further
out
figures 5.7 and 5.9
Extent, Rates, and Causes of Marine Transgressions and Regressions
land rising and fallling
ice ages (water level drops)
Fossilization and Fossils
fossils
body fossils (bones, shells, teeth)
trace fossils (footprints, burrows)
rapid burial-best bet, but rare
molds and casts; mummification, mineral replacement, permineralization, amber,
tar pits
Figures 5.15 and 5.16, **Table 5.1**
Fossils and Telling Time
William Smith (English surveyor- 1800s) Principle of Fossil Succession (or
faunal succession)
correlation-Figure 5.17
Relative Geologic Time Scale...Fig. 5.18..will be on the TESTS
geologic column
Stratigraphic Terminology
lithographic unit-formation
Time units: Era-Period-Epoch-Age (going from largest to shortest time block)
correlation- Figure 5.21
Absolute Dates (years) vs. Relative Geologic Time (names)