Foraminiferal, radiolarian, and dinoflagellate biostratigraphy of Late Cretaceous to Middle Eocene pelagic sediments (Muzzle Group), Mead Stream, Marlborough, New Zealand

<p>The Glenburn Formation of the East Coast of New Zealand is a Late Cretaceous sedimentary formation consisting of alternating layers of sandstone, mudstone and conglomerate. The Glenburn Formation spans a depositional timeframe of over 10 Ma, is over 1000 m thick, is regionally extensive and is possibly present over large areas offshore. For these reasons, it is important to constrain the paleoenvironment of this unit. Late Cretaceous paleogeographic reconstructions of the East Coast Basin are, however, hampered by a number of factors, including the pervasive Neogene to modern tectonic deformation of the region, the poorly understood nature of the plate tectonic regime during the Cretaceous, and a lack of detailed sedimentological studies of most of the region’s Cretaceous units. Through detailed mapping of the Glenburn Formation, this study aims to improve inferences of regional Cretaceous depositional environments and paleogeography. Detailed facies based analysis was undertaken on several measured sections in eastern Wairarapa and southern Hawke’s Bay. Information such as bed thickness, grain size and sedimentary structures were recorded in order to identify distinct facies. Although outcrop is locally extensive, separate outcrop localities generally lie in different thrust blocks, which complicates comparisons of individual field areas and prevents construction of the large-scale, three-dimensional geometry of the Glenburn Formation. Glenburn Formation consists of facies deposited by sediment gravity flows that were primarily turbidity currents and debris flows. Facies observed are consistent with deposition on a prograding submarine fan system. There is significant variation in facies both within and between sections. Several distinct submarine fan architectural components are recognised, such as fan fringes, fan lobes, submarine channels and overbank deposits. Provenance and paleocurrent indicators are consistent with deposition having occurred on several separate submarine fans, and an integrated regional paleogeographic reconstruction suggests that deposition most likely occurred in a fossil trench following the mid-Cretaceous cessation of subduction along the Pacific-facing margin of Gondwana.</p>

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Structural setting and tectonic evolution of the Bahariya Depression, Western Desert, Egypt

GeoArabia ◽

10.2113/geoarabia080191 ◽

2003 ◽

Vol 8 (1) ◽

pp. 91-124 ◽

Cited By ~ 1

Author(s):

Adel R Moustafa ◽

Ati Saoudi ◽

Alaa Moubasher ◽

Ibrahim M Ibrahim ◽

Hesham Molokhia ◽

...

Keyword(s):

Late Cretaceous ◽

Tectonic Evolution ◽

Middle Miocene ◽

Middle Eocene ◽

Western Desert ◽

Normal Faults ◽

Surface Mapping ◽

Early Mesozoic ◽

Hydrocarbon Fields ◽

Stable Area

ABSTRACT An integrated surface mapping and subsurface study of the Bahariya Depression aided the regional subsurface interpretation. It indicated that four major ENE-oriented structural belts overlie deep-seated faults in this part of the ‘tectonically stable’ area of Egypt. The rocks of the Bahariya area were deformed in the Late Cretaceous, post-Middle Eocene, and Middle Miocene-and subsurface data indicated an early Mesozoic phase of normal faulting. The Late Cretaceous and post-Middle Eocene deformations reactivated the early normal faults by oblique slip and formed a large swell in the Bahariya region. The crest was continuously eroded whereas its peripheries were onlapped by Maastrichtian and Tertiary sediments. The tectonic evolution of the Bahariya region shows great similarity to the deformation of the ‘tectonically unstable’ area of the northern Western Desert where several hydrocarbon fields have been discovered. This similarity may indicate that the same phases of deformation could extend to other basins lying in the ‘tectonically stable’ area, such as the Asyut, Dakhla, Nuqura, and El Misaha basins.

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Late Cretaceous-Middle Eocene olistrostromal pelagic units in the Biga Peninsula (NW Anatolia); Balıkkaya formation

Bulletin Of The Mineral Research and Exploration ◽

10.19111/bulletinofmre.719876 ◽

2020 ◽

pp. 1-32

Author(s):

Serdar AKGÜNDÜZ ◽

İzver ÖZKAR ÖNGEN

Keyword(s):

Late Cretaceous ◽

Middle Eocene ◽

Biga Peninsula

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The Cretaceous and Paleocene pleurotomariid (Gastropoda: Vetigastropoda) fauna of Seymour Island, Antarctica

Journal of Paleontology ◽

10.1666/09-004.1 ◽

2009 ◽

Vol 83 (5) ◽

pp. 750-766 ◽

Cited By ~ 5

Author(s):

M. G. Harasewych ◽

Anton Oleinik ◽

William Zinsmeister

Keyword(s):

Species Richness ◽

New Zealand ◽

South America ◽

Late Cretaceous ◽

Upper Cretaceous ◽

Southern India ◽

New Combination ◽

The Family ◽

The Status ◽

Seymour Island

Leptomaria antipodensis and Leptomaria hickmanae are described from the Upper Cretaceous [Maastrichtian] Lopez de Bertodano Formation, Seymour Island, and represent the first Mesozoic records of the family Pleurotomariidae from Antarctica. Leptomaria stillwelli, L. seymourensis, Conotomaria sobralensis and C. bayeri, from the Paleocene [Danian], Sobral Formation, Seymour Island, are described as new. Leptomaria larseniana (Wilckens, 1911) new combination, also from the Sobral Formation, is redescribed based on better-preserved material. The limited diversity of the pleurotomariid fauna of Seymour Island is more similar to that of the Late Cretaceous faunas of Australia and New Zealand in terms of the number of genera and species, than to the older, more diverse faunas of South America, southern India, or northwestern Madagascar, supporting the status of the Weddelian Province as a distinct biogeographic unit. The increase in the species richness of this fauna during the Danian may be due to the final fragmentation of Gondwana during this period.

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Linuparus korura n. sp. (Decapoda: Palinura) from the Bortonian (Eocene) of New Zealand

Journal of Paleontology ◽

10.1017/s0022336000029887 ◽

1988 ◽

Vol 62 (2) ◽

pp. 245-250 ◽

Cited By ~ 7

Author(s):

Rodney M. Feldmann ◽

Robert K. Bearlin

Keyword(s):

New Zealand ◽

Fossil Record ◽

Middle Eocene ◽

Species Comparison ◽

Morphological Descriptors ◽

First Occurrence ◽

First Time ◽

Pacific Species

Linuparus (Linuparus) korura n. sp. is described from Bortonian (middle Eocene) rocks in Otaio Gorge, South Canterbury, New Zealand. This discovery represents the first occurrence of the genus in New Zealand and the first notice of a fossil occurrence of the subgenus which is represented by three modern Indo-Pacific species. Comparison of key morphological descriptors suggests that L. korura is related to L. scyllariformis and L. trigonis. A stridulatory mechanism, similar to that seen on modern Linuparus, is described for the first time from the fossil record.

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Bicarinellata a new name for Bicarinella Rode, Lieberman, and Rowell, 2003 (Arthopoda, Bradoriida) preoccupied by Bicarinella Waterhouse, 1966 (Mollusca, Gastropoda) and Bicarinella Akopyan, 1976 (Mollusca, Gastropoda)

Journal of Paleontology ◽

10.1017/s002233600005544x ◽

2008 ◽

Vol 82 (6) ◽

pp. 1220-1220 ◽

Cited By ~ 2

Author(s):

Alycia L. Stigall

Keyword(s):

New Zealand ◽

Late Cretaceous ◽

Type Species ◽

East Antarctica ◽

Zoological Nomenclature ◽

Early Cambrian ◽

International Code ◽

New Name ◽

Valid Genus ◽

The One

The genus Bicarinella Rode et al., 2003 was erected for a new hipponicharionid bradoriid species described from the early Cambrian of East Antarctica, characterized by a subtriangular carapace with prominent anterior and posterior lobes developed as two distinctive, sharp ridges (bi = two, carina = ridges). Unfortunately, the name Bicarinella is preoccupied by two different gastropod genera: Bicarinella Waterhouse 1966, a Permian gastropod from New Zealand and Australia, and Bicarinella Akopyan 1976, a gastropod from Late Cretaceous strata of Armenia, Serbia, Romania, Tajikistan, and Egypt (Mennessier, 1994; Banjac, 1998; Pana, 1998). Mennessier (1994) transferred Bicarinella Akopyan, 1976 from its original status as an independent taxon to a subgenus of Pseudomesalia Douvillé 1916, but subsequent workers have continued to consider Bicarinella a valid genus (Pena, 1998; Banjac, 1998). Due to the preoccupation, the bradoriid genus is herein renamed in accordance with the requirement of the International Code of Zoological Nomenclature (1999, article 60). It is also noted here that the one of the two distinct gastropod genera should be renamed. The name Bicarinellata (bi = two, carina = ridges) is proposed as a replacement name for Bicarinella Rode et al., 2003. This name retains the original prefixes to preserve taxonomic stability as much as possible. The type species of Bicarinellata is B. evansi by original designation (Rode et al., 2003).

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Fossil crocodilian distributions, Upper Cretaceous to present: implications for paleoclimate

The Paleontological Society Special Publications ◽

10.1017/s2475262200007589 ◽

1992 ◽

Vol 6 ◽

pp. 198-198

Author(s):

Paul Markwick

Keyword(s):

Late Cretaceous ◽

Middle Eocene ◽

Global Climate ◽

A Priori ◽

Tropical Regions ◽

Cooling Trend ◽

Geologic Record ◽

Continental Interior ◽

Different Levels ◽

Limited Scope

The present day distribution of crocodilians appears to be climatically controlled, at least in part, with the group restricted to tropical through sub-tropical regions. Studies have shown that although crocodiles may be able to withstand sub-zero temperatures they can do so for only limited periods. By analogy the presence of fossil crocodilians in the geologic record has been interpretated as indicating warmth. However previous studies have generally been of limited scope. This study uses global paleodistributions of the crocodilians to map gross global climate for the last 100 million years.A comprehensive database of published occurrences of fossil crocodilians from the late Cretaceous to the Present has been constructed. Taphonomic and collection biases have been addressed using ‘control groups', these are respectively the Testudines and the vertebrates in general. Problems of taxonomic inconsistency have been dealt with by ‘accepting’ a standard published taxonomic scheme (Carroll, 1988). Geographic and temporal uncertainties and imprecisions are coded on the database to facilitate sorting; this allows the analyses to be run at different levels of precision and provides an opportunity to understand the way biogeographic and hence paleoclimatic interpretations may be influenced by both the nature of the geologic record itself and by a priori decisions made by the worker. The database also includes lithologic, stratigraphic and environmental information on some 3300 localities and includes specimen information for the taxa entered (>14000 separate entries assembled from 1000 references).Preliminary analyses of paleolatitudinally reconstructed localities reveals the following trends: an overall equatorward movement of the poleward limit of the crocodiles from the late Cretaceous to the present; this is punctuated by an abrupt equatorward excursion of almost 10° during the Oligocene and another of similar magnitude at the end of the Miocene, with an apparent Miocene ‘recovery’ in between (this trend is shown most clearly by the families Alligatoridae and Crocodylidae). At the suborder level the Mesosuchians (excluding the Sebecidae) show a distinct equatorial shift from the Campanian through to the middle Eocene when they disappear; inclusion of the Sebecidae in the Mesosuchia gives rise to a sudden poleward expansion in the middle Eocene of some 20° paleolatitude. Map reconstructions, especially for North America, reveal an eastward shift of crocodilian localities as the Tertiary progresses, perhaps due in part to a taphonomic artifact, viz., the migration of the locus of sedimentation. With the late Miocene the crocodilians disappeared completely from the continental interior record, a transition which seems tied to increased aridity (as indicated by the development of caliches in many areas) and increased seasonality of temperature. This pattern is also seen in the southern ‘U.S.S.R’.The distributions of the Crocodylia through time therefore reflect and support established views concerning late Cretaceous through Tertiary climate with a general cooling trend from the late Cretaceous to the present punctuated by abrupt coolings in the Oligocene and around the Miocene-Pliocene boundary.

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