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Surface sediment samples collected from the fjord region of southern Chile (47° to 54° South) were analyzed for benthic foraminifera. A total of 175 species were identified including agglutinated and calcareous benthic taxa. Hierarchical cluster analysis of the foraminiferal data resulted in the recognition of three distinct biofacies: inner-fjord, intermediate fjord and channel, and oceanic biofacies, geographically controlled by relative position between the Pacific Ocean and fjord heads. Similarity percentage (SIMPER) analysis identified key taxa in the definition of the biofacies that include Globocassidulina rossensis , Cassidulina laevigata and Bulimina notovata . Principal components analysis resulted in two principal components representing sediment size, and bottom water temperature and salinity. Regional distributions are strongly controlled by the oceanographic conditions influenced from the Pacific in the west and the glacial/freshwater input from the east. Localized distributions of foraminifera are controlled by conditions influenced by the physiography of the individual fjords and channels. The distribution of Chilean fjord foraminifera and their environmental associations are consistent with results from other temperate to high latitude fjord foraminiferal studies. |
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