Chapter 8.2 Modern Algal Stromatolites at Hamelin Pool, A Hypersaline Barred Basin in Shark Bay, Western Australia

Abstract

Publisher Summary Algal stromatolites are forming today over wide areas of the sublittoral platform and adjacent intertidal zone fringing Hamelin Pool, a hyperialine barred basin at the southeastern extremity of Shark Bay in Western Australia. They are the most diverse and abundant shallow-water stromatolites known from modern seas. The fauna of Hamelin Pool is very restricted in species diversity because of the hypersaline conditions, and algae-consuming organisms are largely absent. As a result, algal stromatolites and flat algal-mat sheets flourish on the sublittoral and intertidal platforms. Living stromatolites in Hamelin Pool extend from depths of at least 3.5 m below sea level to about high-water-spring tide level. Older dead stromatolites in varying states of disintegration occur above this level, and these have probably emerged as a result of Holocene uplift, which may still be continuing. A considerable amount of additional work is necessary before the Hamelin Pool stromatolites can be fully described and classified. It is desirable that a comprehensive system of nomenclature be developed for them, which also has applications in the classification of ancient stromatolites.