Subtropical coral-reef associated sedimentary faciès characterized by molluscs (Northern Bay of Safaga, Red Sea, Egypt)
- Autor(en)
- Martin Zuschin, Johann Hohenegger
- Abstrakt
The shallow marine subtropical Northern Bay of Safaga is composed of a complex pattern of sedimentary faciès that are generally rich in molluscs. Thirteen divertaken bulk-samples from various sites (reef slopes, sand between coral patches, muddy sand, mud, sandy seagrass, muddy seagrass, mangrove channel) at water depths ranging from shallow subtidal to 40m were investigated with regard to their mollusc fauna >lmm, which was separated into fragments and whole individuals. Fragments make up more than 88% of the total mollusc remains of the samples, and their proportions correspond to characteristics of the sedimentary faciès. The whole individuals were differentiated into 622 taxa. The most common taxon, Rissoina cerithiiformis, represented more than 5 % of the total mollusc content in the samples. The main part of the fauna consists of micromolluscs, including both small adults and juveniles. Based on the results of cluster-, correspondence-, and factor analyses the fauna was grouped into several associations, each characterizing a sedimentary facies: (1) "'Rhinoclavis sordidula - Corbula erythraeensis Pseudominolia nedyma association" characterizes mud. (2) "Microcirce sp. - Leptomyaria sp. association" characterizes muddy sand. (3) "Smaragdia spp. - Perrinia stellata - Anachis exilis - assemblage" characterizes sandy seagrass. (4) "Crenella striatissima - Rastafaria calypso - Cordites akabana - assemblage" characterizes muddy seagrass. (5) "Glycymeris spp. - Pan'icardium sueziensis - Diala spp. - assemblage" characterizes sand between coral patches. (6) "Rissoina spp. - Triphoridae - Ostreoidea - assemblage" characterizes reef slopes. (7) "Potamides conicus - Siphonaria sp. 2 - assemblage" characterizes the mangrove. The seagrass fauna is related to those of sand between coral patches and reef slopes with respect to gastropod assemblages, numbers of taxa and diversity indices, and to the muddy sand fauna on the basis of bivalve assemblages and feeding strategies of bivalves. The mangrove assemblage is related to those of sand between coral patches and the reef slope with respect to taxonomic composition and feeding strategies of bivalves, but has a strong relationship to those of the fine-grained sediments when considering diversity indices. Reef slope assemblages are closely related to that of sand between coral patches in all respects, except life habits of bivalves, which distinctly separates the reef slope faciès from all others.
- Organisation(en)
- Institut für Paläontologie, Dekanat der Fakultät für Lebenswissenschaften
- Journal
- Facies
- Band
- 38
- Seiten
- 229-254
- Anzahl der Seiten
- 26
- ISSN
- 0172-9179
- Publikationsdatum
- 12-1998
- Peer-reviewed
- Ja
- ÖFOS 2012
- 105118 Paläontologie, 106021 Meeresbiologie
- Schlagwörter
- ASJC Scopus Sachgebiete
- Geology, Stratigraphy, Palaeontology
- Sustainable Development Goals
- SDG 14 – Leben unter Wasser
- Link zum Portal
- https://ucris.univie.ac.at/portal/de/publications/subtropical-coralreef-associated-sedimentary-facies-characterized-by-molluscs-northern-bay-of-safaga-red-sea-egypt(e59772da-2903-4789-8e01-78aeb2d6a975).html