Post on 30-Nov-2014
description
Sedimentary Rocks
What are they?
3 types: Clastic or Terrigenous Biogenic Chemical
Clastic or Terrigenous sedimentary rocks WEDCC
Many depositional locations: Continental Shoreline Marine
Grain SizeName of Particle Size Range Loose Sediment Consolidated Rock
Boulder >256 mm Gravel
Conglomerate or Breccia (depends on rounding)
Cobble 64 - 256 mm Gravel
Pebble 2 - 64 mm Gravel
Sand 1/16 - 2mm Sand Sandstone
Silt 1/256 - 1/16 mm Silt Siltstone
Clay <1/256 mm Clay Claystone, mudstone, and shale
Texture Sorting- how uniform
the particle size is
Rounding- angular to rounded
Sedimentary structures
Bedding (stratification) Cross-bedding Ripples Fossils
Biogenic sedimentary rocks
Usually carbonate sediments
Classified by mineral composition
Created through biological processes
Limited depositional location
Chemical sedimentary rocks
precipitation of salts from solution Marine or non-marine Gypsum Halite