GEOL 2530 Lecture Notes - Lecture 5: Bioerosion, Caliche, Clay Minerals

• School: University of Manitoba
• Department: Geological Sciences
• Course: GEOL 2530
• Professor: Chow Nancy

Document Summary

Modern - aragonite calcite low mg calcite - high mg calcite - skeletal & non-skeletal grains. Ancient - lmc and dolomite: diagenesis aragonite, hmc lmc. 2caco3(s) + mg2+ (aq) camg(co3)2 (s) + ca2+ (aq: original mineralogy. Lithoclasts: ooids (oolite) < 2 mm diameter. Ancient marine radial-fibrous, lmc: peloids - silt- to sand-size grains of micrite. Intraclasts: aggregate grains - bound by cement or om. Modern reef-builders tropical, shallow-marine, high-energy e. g. stromatoporoids. Paleozoic reef-builders tropical, shallow-marine, high to low energy. Sources: disintegration of calcareous green algae, bioerosion, biochemical precipitation, inorganic precipitation. 5. 3. 4 sparite: large, clear lmc crystals, fibrous/prismatic hmc or aragonite - radially oriented. Formation: replacement of caco3 components minerals (dolomitization, dolomite cement, direct precipitation from seawater or lacustrine waters. Rock-water interactions: marine realm, meteoric realm, subsurface realm. Marine: hardground - synsedimentary lithification of sea floor (subtidal, beachrock - synsedimentary lithification in intertidal - supratidal zones, carbonate compensation depth (ccd) 6 karren - meter-scale karst landforms - large-scale.