COOL-WATER CARBONATES AND THE NULLARBOR KARST SYSTEM, SOUTHERN AUSTRALIA

摘要

Carbonate rocks are host to the world's great karst systems. Many such systems are relatively young, having developed coincident with initial subaerial exposure of carbonate sediments that were deposited in tropical marine environments. Such sediments, composed of metastable carbonate minerals, alter to low magnesium calcite and in the process rapidly lithify, in some cases in as few as 10,000 years (Tucker and Wright, 1990). Such cementation is largely achieved by the dissolution of aragonite in fresh waters and the reprecipitation of carbonate as low-Mg calcite cement.