History of investigation and description of the physical environment

WA Museum Records and Supplements | Updated 1 decade ago

Abstract: The Rowley Shoals (comprising three distinct reefs), Scott Reef and nearby Seringapatam Reef form a series of large emergent shelf atolls arising from depths of between 300 and 700 m along the edge of the broad continental shelf about 260 km from mainland north-western Australia. The Rowley Shoals have been descrived as morphologically the most perfect examples of shelf atolls in Australian waters and appear to represent three distinct examples of shelf atolls in Australian waters and appear to represent three distinct stages in atoll formation. Scott Reef has been drilled to reveal an entirely sedimentary sequence to 4720 m at which the Late Triassic was reached. It seems likely that the other atolls also have a marine sedimentary structure and that reef groth has proceeded intermittently since the mid-Miocene, activated by depression of the shelf edge and changes in sea level. 

Experiencing oceanic water conditions, but with a semi-diurnal tidal range of at least 4.5 m, these atolls exhibit an unusual, if not unique, combination of physical environmental and geomorphological characteristics. These are described as a background to the faunal inventories presented in subsequent parts of this publication.