Planktonic foraminifera form the Upper Cretaceous Pierre Shale at Red Bird, Wyoming

1982 ◽  
Vol 12 (4) ◽  
pp. 353-361 ◽  
Author(s):  
T. J. Bergstresser ◽  
W. E. Frerichs
Keyword(s):  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
Pierre Shale

Planktonic foraminifera and dinoflagellate cysts from the Upper Cretaceous Abderaz Formation in the Koppeh-Dagh Basin, NE Iran

Stratigraphy ◽  
2018 ◽  
Vol 15 (1) ◽  
pp. 47-66
Author(s):  
Elham Davtalab ◽  
Mohammad Vahidinia ◽  
Ebrahim Ghasemi-Nejad ◽  
Alireza Ashouri
Keyword(s):  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
Dinoflagellate Cysts ◽  
Ne Iran

The crucial boundaries in the development of the late cretaceous biota of plankton foraminifers in the southern part of the Indian ocean

2019 ◽  
Vol 59 (6) ◽  
pp. 1074-1085
Author(s):  
E. A. Sokolova
Keyword(s):  
Indian Ocean ◽  
Species Composition ◽  
Late Cretaceous ◽  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
The Indian Ocean ◽  
Systematic Composition ◽  
Climatic Series

The article analyzes own data on the species composition of shells of planktonic foraminifera from the Upper Cretaceous sediments of the Indian Oceans, as well as from the sections of the offshore seas of Australia. The species of planktonic foraminifera are grouped and arranged in a climatic series. An analysis of the change in the systematic composition of foraminifers made it possible to distinguish periods of extreme and intermediate climatic states in the Late Cretaceous.

Upper Cretaceous Stratigraphy and Volcanism in the İğneada region, Pontides, NW Turkey

2020 ◽  
Author(s):  
Ezgi Sağlam ◽  
Turgut Duzman ◽  
Aral I. Okay
Keyword(s):  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
Lava Flows ◽  
Arc Volcanism ◽  
Magmatic Arc ◽  
Andesitic Lava ◽  
Black Sea Coast ◽  
Nw Turkey ◽  
Sandy Limestone ◽  
Volcaniclastic Rocks

<p>The Pontide Upper Cretaceous magmatic arc can be traced for over 1000 km along the southern Black Sea coast from Georgia to Bulgaria.  The arc extrusive sequence is well-exposed in the İğneada region in Thrace close to the Bulgarian border. The Upper Cretaceous sequence in İğneada region overlies the schists and phyllites of Strandja Massif with an unconformity. It  has a thickness of over 700 meters and consists at the base of Cenomanian shallow marine sandy limestone, which pass up into pelagic limestone, marn and volcanogenic siltstone with Turonian planktonic foraminifera, including <em>Marginotruncana pseudolinneana</em>, <em>Marginotruncana marginata</em>, <em>Whitenella</em> sp., <em>Whitenella praehelvetica</em>, <em>Muricohedbergella</em> sp.  This indicates that the arc volcanism in the region started in the Turonian. The pelagic limestone, marl, and calcareous siltstone series passes up into a volcanic-volcaniclastic sequence of andesitic tuff, lapillistone, agglomerate, andesitic and basaltic-andesitic lava flows. The volcaniclastic rocks are intercalated with lava flows and with rare pelagic limestone and shale beds. Although it is disrupted by several faults, the volcanic sequence can be traced from older to younger along the coast of İğneada. The sequence starts with andesitic volcaniclastic rocks and lava flows, and changes to basaltic-andesitic and then, again to andesitic rocks. The ocean floor alteration, which is found in all volcaniclastic and volcanic rock samples, and the intercalated pelagic limestones show that the rocks were deposited in deep submarine conditions in an intra-arc to fore-arc environment. Campanian (80.6 ±1.5 Ma) U-Pb zircon ages, which are obtained from the andesitic tuffs at the base of the volcanic-volcaniclastic sequence, indicate a continued magmatism from Turonian to Campanian.</p>

scholarly journals Stratigraphy and Sedimentology of Upper Cretaceous to Upper Palaeocene Succession in Zimam Formation Along Wadi Tar al Kabir, NW Libya

2020 ◽  
Vol 9 (2) ◽  
pp. 1
Author(s):  
Esam O. Abdulsamad ◽  
Saleh A. Emhanna ◽  
Muayid B. Asmaeil ◽  
Ahmed A. Alwddani ◽  
Fuad M. Rasheed ◽  
...  
Keyword(s):  
Benthic Foraminifera ◽  
Upper Cretaceous ◽  
Planktonic Foraminifera ◽  
Sedimentary Facies ◽  
Larger Benthic Foraminifera ◽  
Sedimentary Cycles ◽  
Total Range ◽  
Field Investigations ◽  
Sedimentary Cycle ◽  
Nw Libya

The Upper Cretaceous to Upper Palaeocene rocks of the Zimam Formation along the southwestern escarpment of the Hun Graben of NW Libya have been stratigraphically investigated from two stratigraphical sections in wadi Tar al Kabir. The field investigations led to the recognition of three members, from the oldest to the youngest, the Lower Tar Member, the Upper Tar Member and the Had Member. Eight sedimentary facies were distinguished at outcrop-scale and several microfacies were recognized and the outcome indicates that the depositions of the Zimam Formation are corresponding to two transgressive-regressive sedimentary cycles. The first cycle is attributed to the Lower Tar Member in which small planktonic foraminifera is quite common in the Campanian whereas the larger benthic foraminifera, namely, Omphalocyclus macroporus and Siderolites calcitrapoides are abundant in the Maastrichtian. The last occurrence of the latter two taxa, however, was used to delineate the contact between the Maastrichtian and Danian stages in the studied sequence. Up-sequence the sediments of the Upper Tar Member along with the overlying Had Member correspond to the second transgressive-regressive sedimentary cycle. Herein, the Upper Tar Member is enriched by small benthic foraminifera; Neoeponides duwi and Cibicides cf. libycus, and has been ascribed to the Danian (Lower Palaeocene). The reaming sediments of Zimam Formation, however, are belonging to the overlying Had Member and is tentatively ascribed to the Selandian (Upper Palaeocene) based on the last occurrence of the Danian fauna and the total range of the codiacean algae Ovulites morelleti.

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