Biogeographic and bathymetric distribution of benthic foraminifera in Paleocene El Haria Formation of Tunisia

In Tunisia, the Paleocene biomarkers are identified within the El Haria Formation shales. The Selandian is absent in most of the Paleocene outcrops and the Thanetian is unconformable to different stages of the Cretaceous. In the middle of Selandian, with the beginning of the Globanomalina pseudomenardii (P4) zone, we note that the assemblage of planktonic foraminifera becomes very poorly preserved and much less abundant than at the base. It is represented by rare species and there has been a start of the microfauna dissolution tests and an enrichment in iron oxides, silica, and gypsum crystals. The dissolution process is increasing more and more and a drop in the content of carbonates is clearly recorded at the top of Selandian. However, we note that some small benthic foraminifera belonging to the genera Lenticulina and Anomalina escape the dissolution and very few planktonic foraminifera belonging to the genera Subbotina are preserved. This dramatic and abnormal dissolution extends over a considerable thickness. These features could be an expression of the mid-Paleocene biotic event (MPBE), registered for the first time in Tunisia. This intense dissolution is caused probably by the change in the solubility of carbonates, which may be related to the changes in the deep-water circulation or to the change in the productivity of the surface waters.

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Bathymetric distribution of benthic foraminifera on the Australian-Irian Jaya continental margin, eastern Indonesia

Marine Micropaleontology ◽

10.1016/0377-8398(88)90001-1 ◽

1988 ◽

Vol 13 (2) ◽

pp. 97-152 ◽

Cited By ~ 38

Author(s):

L.J. Van Marle

Keyword(s):

Continental Margin ◽

Benthic Foraminifera ◽

Bathymetric Distribution ◽

Irian Jaya ◽

Eastern Indonesia

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Benthic foraminiferal zonation in deep-water carbonate platform margin environments, northern Little Bahama Bank

Journal of Paleontology ◽

10.1017/s0022336000058819 ◽

1988 ◽

Vol 62 (01) ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Ronald E. Martin

Keyword(s):

Deep Water ◽

Benthic Foraminifera ◽

Carbonate Platform ◽

Sedimentary Facies ◽

Depositional Environments ◽

Near Surface ◽

Sediment Gravity Flows ◽

Gravity Flows ◽

Platform Margin ◽

Water Carbonate

The utility of benthic foraminifera in bathymetric interpretation of clastic depositional environments is well established. In contrast, bathymetric distribution of benthic foraminifera in deep-water carbonate environments has been largely neglected. Approximately 260 species and morphotypes of benthic foraminifera were identified from 12 piston core tops and grab samples collected along two traverses 25 km apart across the northern windward margin of Little Bahama Bank at depths of 275-1,135 m. Certain species and operational taxonomic groups of benthic foraminifera correspond to major near-surface sedimentary facies of the windward margin of Little Bahama Bank and serve as reliable depth indicators. Globocassidulina subglobosa, Cibicides rugosus, and Cibicides wuellerstorfi are all reliable depth indicators, being most abundant at depths >1,000 m, and are found in lower slope periplatform aprons, which are primarily comprised of sediment gravity flows. Reef-dwelling peneroplids and soritids (suborder Miliolina) and rotaliines (suborder Rotaliina) are most abundant at depths <300 m, reflecting downslope bottom transport in proximity to bank-margin reefs. Small miliolines, rosalinids, and discorbids are abundant in periplatform ooze at depths <300 m and are winnowed from the carbonate platform. Increased variation in assemblage diversity below 900 m reflects mixing of shallow- and deep-water species by sediment gravity flows.

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Stratigraphy and larger benthic foraminifera of Middle Eocene to Middle Miocene rocks along the Tobruk-Al Bardia scarps, northeastern Cyrenaica, Libya

Stratigraphy ◽

10.29041/strat.15.3.153-178 ◽

2018 ◽

Vol 15 (3) ◽

pp. 153-178

Author(s):

Esam O. Abdulsamad ◽

Salah S. El-Ekhfifi ◽

Ahmed M. Muftah

Keyword(s):

Benthic Foraminifera ◽

Middle Miocene ◽

Middle Eocene ◽

Larger Benthic Foraminifera

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THE ABUNDANCE OF RECENT FORAMINIFERA IN SURFACE SEDIMENT OF AMBON BAY

Jurnal Ilmu dan Teknologi Kelautan Tropis ◽

10.29244/jitkt.v2i1.7859 ◽

2010 ◽

Vol 2 (1) ◽

Author(s):

Suhartati M. Natsir

Keyword(s):

Surface Sediment ◽

Benthic Foraminifera ◽

Sea Water ◽

Planktonic Foraminifera ◽

Sediment Characteristic ◽

Abundance And Distribution

Foraminifera are generally live in sea water with various sizes. These organisms consist of planktonic and benthic foraminifera. Geological activity on plutonic and volcanic with vomiting magma is transpiring on, and then affects sedimentation and foraminiferal abundance of Ambon Bay. The study was determined to study the abundance and distribution of foraminifera based on the sediment characteristic of Ambon Bay. Sample collected in 2007 of Ambon Bay showed that only 29 samples of 50 samples containing foraminifera. The collected sediments have 86 species of foraminifera, consisting 61 species of benthic foraminifera and 25 species of planktonic foraminifera. The dominant benthic foraminifera in the surface sediment of Ambon bay were Amphistegina lessonii, Ammoniabeccarii,Elphidium craticulatum,Operculina ammonoides and Quinqueloculina parkery. The planktonic foraminifera that were frequently collected from the bay were Globorotalia tumida, Globoquadrina pseudofoliata, Globigerinoides pseudofoliata, Globigerinoides cyclostomus dan Pulleniatina finalis. Generally, the species dwelled as abundant on substrate sand, whereas the areas within substrate mud have no foraminifera lie on them. Keywords: Foraminifera, Abundance, Sediment, Ambon Bay

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