Fresh Ooids under the Microscope!
Ooids are small carbonate grains formed in shallow, tropical seas.
Ooids are small, well-rounded carbonate grains formed in warm, shallow waters with sufficient agitation.
These Bahamian ooids were filled into snap caps on a recent field trip as an example for our lab and geology students.
Shallow-water coral reef limestones and oolites (rocks made up of ooids) can be excellent hydrocarbon reservoirs due to their coarse skeletal constituents, large pore spaces, and easy dissolution opening up new pore spaces (but sometimes also precipitation!).
Fun fact: First time getting exposed to oolites in my life as geologist was a Jurassic formation in southern Germany, a location where oolites were first described in the 1500s. The geologists described the texture to look like fish eggs (roe).
