Carbonates

Carbonate Textures
• Grains (framework) - skeletal and non-skeletal
• Mud/micrite (matrix) - mircrocrystalline calcite
• Spar (cement) - crystalline calcite
• Significance framework/matrix - environmental & diagenetic

Carbonate Classification
• Two major classification schemes
• Folk - abundance of grains, micrite, spar
• Dunham - depositional textures
Carbonate Classification
• Folk - abundance of grains, micrite, spar

Carbonate Classification
• Dunham - depositional textures
• Grain type = prefix

Carbonate Classification
• Grainstone
• Grain to grain contact + spar

Carbonate Classification
• Packstone
• Grain to grain contact + micrite

Carbonate Classification
• Wackestone
• Grains but not grain supported + micrite

Carbonate Classification
• Mudstone
• Primarily micrite

Carbonate Classification
• Dunham - depositional textures
• Grains > 2mm - floatstone, rudstone
• Autochthonous

Assignment
• Working in groups of 3-4
• Examine the carbonate rock samples
– Record #, texture, components, rock name, environment
• Rocks 1-11
• Rocks and Slides
• Peels