Cretaceous karst guyots: New evidence for inheritance of atoll morphology from subaerial erosional terrain

摘要

Data from recent surveys and drilling suggest that carbonate platforms over a wide region of the oceanic western Pacific became emergent by amounts of 100-200 m during late Albian time, ca. 100 Ma. The resulting erosional landscapes, now modified by differential compaction over the buried volcanic basement hills, included central basins surrounded by perimeter rims, sinkhole-like depressions, and perimeter benches interpreted as wave-cut terraces. Resubmergence resulted in the sealing of atoll-like erosional topography by pelagic sediments. These Cretaceous proto-atolls, now guyots, provide evidence that ancient as well as modern atolls inherit their form mainly from subaerial landscapes.