1. Clastic / Physical / Detrital Chemical Bioclastic/Biochemical
Sedimentary Rocks
Clastic / Physical / Detrital
Chemical
Bioclastic/Biochemical

2. ss, cong sh ss, sh ss, slt, sh ss till ls sh ss, slt, sh graywacke
chert, chalk, sh
Fig

3. Sedimentary Rocks Clastic/Physical/Detrital Sedimentary Rocks
classified by texture (grain size, roundness)
Conglomerate (with rounded gravel)
Breccia (with angular gravel)
Sandstone (sand)
Siltstone (silt)
Claystone or Mudstone (clay)
Shale – fissile (clay)

4. Sedimentary Rocks Chemical Sedimentary Rocks classified by composition
Limestone (many varieties) – Calcite, Dolomite
oolitic LS, crystalline LS, travertine, dolostone
Chert – Silica
Evaporites – Halite, Gypsum, Sylvite, Anhydrite
Rock Salt, Rock Gypsum

5. Sedimentary Rocks Biochemical/Bioclastic Sedimentary Rocks
Limestone (many varieties) – Calcite, Dolomite
coquina, fossiliferous LS, chalk, micrite
Chert – diatoms, silica
Coal
peat, lignite, bituminous coal
anthracite – actually metamorphic

6. Sedimentary clasts are classified by grain size (the size of the individual clasts) using the Wentworth Scale:
Wentworth Scale
Boulders
Cobbles
Gravel (pebbles)
Sand
Silt
Clay
Larger clasts require more energy to transport
Smaller clasts require less energy to transport

7. Evaporites Siliceous Rocks Coal and Peat Carbonates
minerals precipitated from evaporating water
Siliceous Rocks
Silica and opalline silica precipitate either organically or inorganically
Coal and Peat
Carbon-rich deposits formed from build-up of plant material in swamps
Carbonates
Variety of limestones composed of calcite, aragonite, and dolomite precipitated either organically or inorganically