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Late Cretaceous Reversal Sequence
Geology, 1975A sequence of 14 reversals (that is, seven periods of reversed polarity) is observed in Maestrichtian sedimentary rocks from the Mendez Shale of Mexico and in cores from Deep Sea Drilling Project Sites 207A and 208, Lord Howe Rise. Data from a paleomagnetic investigation indicate that (1) a brief interval of frequent field reversals occurred at the ...
B. Keating +2 more
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Late Cretaceous–Paleocene Depsits
2020Preceding studies divided the Late Cretaceous deposits in the Cyrenaica Basin into two parts: the first part was deposited on the coast (Al Hilal and Al Athrun formations) and the second part in the inland (Qasr Al Abid, Al Baniyah, Al Majahir and Wadi Dukhan formations).
Osama Rahil Shaltami +3 more
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Caryanthus diversity in the Late Cretaceous
Review of Palaeobotany and Palynology, 2016Abstract Genus Caryanthus with fourteen species represents the most diversified genus in the Normapolles complex. Detailed review of material from Central Europe allowed accurate study of its geographic and stratigraphic distribution. An emended diagnosis of Caryanthus communis Knobloch et Mai, Caryanthus deltoides (Knobloch) Friis, Caryanthus
Zuzana Heřmanová +2 more
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Baja California: Late Cretaceous Dinosaurs
Science, 1967Late Cretaceous dinosaurs have been discovered along the Pacific margin of Baja California. The presence of Hypacrosaurus sp. is suggestive of correlation with the Upper Edmonton Formation, Alberta. Dissimilarities between the Baja California fauna and those from contemporary units along the eastern trend of the ...
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The great transgressions of the Late Cretaceous
Journal of the Geological Society, 1979During the Late Cretaceous (94–64 Ma) sea level was up to 650 m higher than at the start of the Albian, when it was perhaps about the same as it is today. Facies analysis in both the Western Interior of the USA and in NW Europe reveals simultaneous major oscillations in sea level that controlled the principal transgressions and regressions except in ...
J. M. Hancock, E. G. Kauffman
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Aptychi microstructure in Late Cretaceous Ancyloceratina (Ammonoidea)
Lethaia, 2009The microstructure of aptychi (bivalved calcareous coverings on lower jaws) of three genera of Late Cretaceous Ancyloceratina, Baculites, Polyptychoceras and Jeletzkytes is described for the first time on the basis of well-preserved and in situ material from the Western Interior of the USA and Hokkaido, Japan.
Kruta, I. +4 more
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Late Cretaceous Nannoplankton and the Change at the Cretaceous-Tertiary Boundary
1981Abstract Quantitative taxonomic analyses of Late Campanian to Early Danian calcareous nannofossil assemblages suggest worldwide stable ecological conditions in the photic zone during the last 15 million years of the Mesozoic. Late Cretaceous bioprovincialism was strongly paleolatitudinal.
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Late Cretaceous chrysomonad cysts
Palaeogeography, Palaeoclimatology, Palaeoecology, 1972Abstract An abundant and diverse chrysomonad-cyst flora is present in the Marca Shale Member of the Moreno Formation of California. Associated with the siliceous cysts are diatoms, silicoflagellates, radiolarians, and, rarely, Foraminifera. Five preliminary biostratigraphic zones, based on variations in the kinds and quantities of cysts present, are ...
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A late Cretaceous contamination episode of the European–Mediterranean mantle
Earth and Planetary Science Letters, 2008Abstract One of the most challenging issues about the Tertiary–Quaternary alkaline magmatism spreading across the Euro-Mediterranean region is the assessment of both the nature of its mantle source and the mechanism responsible for the common HIMU-like (High μ = high 238U/204Pb) character of erupted lavas, enduring over about 100 million years in ...
PIROMALLO C +3 more
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Late Cretaceous unconformities in the Subhercynian Cretaceous Basin (Germany)
2018In the Subhercynian Cretaceous Basin, six Upper Cretaceous angular unconformities can be observed. The first unconformity, at the base of the Cenomanian transgressive deposits, is not related to the development of the basin. While the second ( Lower to Middle Coniacian) unconformity is almost limited to the northern basin margin, four unconformities ...
Voigt, T. +2 more
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