scholarly journals The palynology of the Kimmeridge Clay and Carstone formations (Upper Jurassic – Lower Cretaceous) at Middlegate Quarry, North Lincolnshire, UK, and its biostratigraphical and palaeoenvironmental significance

2021 ◽  
pp. pygs2021-005
Author(s):  
Roderick D. Black ◽  
Paul Dodsworth
Keyword(s):  
Lower Cretaceous ◽  
Upper Jurassic ◽  
Average Concentration ◽  
Dinoflagellate Cysts ◽  
Content Type ◽  
Palynological Data ◽  
Supplementary Material ◽  
Clay Formation ◽  
First Time ◽  
Lower Kimmeridgian

At Middlegate Quarry, the Carstone Formation is an approximately 0.8 m thick unit of oolitic ferruginous sandstone. It rests unconformably on the lower Kimmeridge Clay Formation (KCF) and is overlain by the Hunstanton Formation (Red Chalk) with an apparently gradational junction. Marine dinoflagellate cysts (dinocysts) are present at a concentration of 9,520 to 13,600 specimens per gramme in the 0.15 m of KCF below the unconformity, and include taxa that confirm ammonite evidence for the intra-Lower Kimmeridgian Substage (Upper Jurassic, Cymodoce Ammonite Zone). A rich recovery of well-preserved Lower Cretaceous palynomorphs is reported for the first time from the overlying Carstone. Reworking of mudstone from the KCF into the formation appears to have provided a local argillaceous preservation matrix at Middlegate. The basal 0.15 m is dominated by palynomorphs derived from the KCF but the interval from 0.15 m to 0.55 m above the unconformity mainly contains indigenous Lower Cretaceous palynomorphs. Dinoflagellate cysts are present in the Carstone at an average concentration of 454 specimens per gramme, and include taxa that probably have stratigraphical range bases above the Aptian – Albian stage boundary; Cyclonephelium compactum, Cyclonephelium intonsum, Endoscrinium heikeae, Leptodinium cancellatum (consistent), Stephodinium coronatum and Stephodinium spinulosum. The additional presence of taxa with range tops / event tops in the Lower Albian Tardefurcata Ammonite Zone (common Cauca parva, frequent Canninginopsis monile and Kleithriasphaeridium eoinodes, and rare Dingodinium albertii, Discorsia nannus and Kiokansium prolatum) indicate probable assignment to this zone. The new palynological data support previous macrofossil (brachiopod) study of the Carstone at Middlegate and nearby Melton Bottom Quarry which tentatively assigns its highest part to the Tardefurcata Zone. The palynological and palynofacies assemblages are interpreted to confirm a relatively proximal to shoreline site of deposition, possibly inner to middle neritic.Supplementary material: One pdf file, with quarry photographs and a palynological distribution chart, is available at https://doi.org/10.6084/m9.figshare.c.5538977

scholarly journals Completely preserved cockroaches of the family Mesoblattinidae from the Upper Jurassic-Lower Cretaceous Yixian Formation (Liaoning Province, NE China)

2013 ◽  
Vol 64 (4) ◽  
pp. 291-304 ◽  
Author(s):  
Dandan Wei ◽  
Dong Ren
Keyword(s):  
Lower Cretaceous ◽  
Hind Wing ◽  
Upper Jurassic ◽  
Morphological Characters ◽  
Yixian Formation ◽  
Liaoning Province ◽  
Tergal Glands ◽  
The Family ◽  
Left And Right ◽  
First Time

Abstract Although cockroaches were the dominant insects in various Paleozoic and Mesozoic insect assemblages, their general morphology was extremely conservative. One of the most common of them, the Jurassic-Cretaceous family Mesoblattinidae, is described here for the first time on the basis of completely preserved specimens. Ninety-two specimens of Perlucipecta aurea gen. et sp. n. reveal details of head, mandible, male tergal glands and terminal hook; cercal, leg and antennal sensilla. Its congener, P. vrsanskyi is described from the same sediments of the Yixian Formation (Upper Jurassic-Lower Cretaceous). The forewing venation variability of P. aurea, analysed for the first time in this family is nearly identical (CV = 6.23 %) with variability of two species of family Blattulidae that occur at the same locality (CV = 6.22 %; 5.72 %). The transitional nature of morphological characters represented by asymmetry between left and right wings (simple/branched forewing SC and hind wing M) in P. aurea documents the phylogenetic relation between the families Mesoblattinidae and Ectobiidae

scholarly journals Biostratigraphy of Upper Jurassic of the Valy clay pit (Samarskaya Luka) by ammonites, ostracods and dinocysts

2021 ◽  
Vol 66 (3) ◽  
Author(s):  
Mikhail A. Rogov ◽  
◽  
Julia N. Savelieva ◽  
Olga V. Shurekova ◽  
◽  
...  
Keyword(s):  
Upper Jurassic ◽  
Ecological Analysis ◽  
Central Russia ◽  
Short Time ◽  
First Time ◽  
The Village ◽  
Upper Kimmeridgian ◽  
Biostratigraphic Units ◽  
Lower Kimmeridgian ◽  
Samarskaya Luka

The results of integrate biostratigraphic study of Upper Jurassic deposits of the clay pit near the village of Valy (Syzran district, Samara region) are presented. For the first time a bed-by-bed description was made and the subdivision of the section into zones, subzones and biohorizons by ammonites was established. Bauhini and Kitchini zones (Bayi subzone) are established in the Lower Kimeridgian, while Upper Kimmeridgian is represented by Autissiodorensis zone only. In the Lower Volgian Sokolovi and Pseudoscythica zones were recognized, while the Middle Volgian is represented by the Panderi zone. The age of the regionally developed unconformity at the base of the Trazovo Formation has been clarified. As in the sections located to the south from studied section, this unconformity is located in the base of the Autissiodorensis zone, overlying different Oxfordian and lower Kimmeridgian. For the first time for Kimmeridgian of Central Russia in the marlstone band of the Kitchini zone (bayi biohorizon) solitary corals conditionally attributed to the genus Trochocyathus were found. Along with corals other warm-water taxa (belemnites Hibolithes, rare ammonites Taramelliceras) were found in the same bed, suggesting deposition of this bed during the short-time warming event. 6 biostratigraphic units (zone and beds with fauna) were recognized by ostracods, along with 2 dinocyst-based units (assemblage and zone) which are compared with the stratigraphic subdivisions by these groups, previously proposed for the Kimeridgian and Volgian stages of the Russian Platform. The paleo-ecological analysis has allowed to assume, that sediments have accumulated in the conditions of warm shallow eutrophic basin with depth to 50 m, with gradual increase of eutrophy through time. At some levels, short-term episodes of severe shallowing or freshening are recorded by ostracods.

The Highlander Field, Block 14/20b, UK North Sea

1991 ◽  
Vol 14 (1) ◽  
pp. 323-329 ◽  
Author(s):  
M. WHITEHEAD ◽  
S. J. PINNOCK
Keyword(s):  
Lower Cretaceous ◽  
Upper Jurassic ◽  
Oil Accumulation ◽  
Shallow Marine ◽  
Oil Development ◽  
The North ◽  
Recoverable Reserves ◽  
Fault Block ◽  
The Witch ◽  
Clay Formation

AbstractHighlander Field, discovered in 1976, is a small oil accumulation located 7½ miles northwest of the Tartan Platform and 114 miles northeast of Aberdeen in UK Block 14/20b. The Field lies on the NW-SE-trending Claymore-Highlander Ridge which forms the southern margin of the Witch Ground Graben. Upper Jurassic sandstones of the shallow marine Piper Formation and deeper marine turbidites (the 'Hot Lens Equivalent') within the Kimmeridge Clay Formation form the principal reservoirs. An additional important reservoir occurs within Lower Cretaceous turbidite sandstone and a small crestal accumulation occurs in Carboniferous deltaic sandstone. The structure is a tilted NW-SE-trending fault block downthrown to the northeast. The sandstone reservoirs all dip to the south and southwest and become thin due to onlap or truncation to the north. The Field has a combined structural-stratigraphic trap configuration. Seal is provided by Upper Jurassic siltstone and Lower Cretaceous calcareous clay stone. The accumulations have been sourced from the Kimmeridge Clay Formation in adjacent basins. Eight wells delineate the structure and production is currently 30 000 BOPD. Ultimate recoverable reserves are 70 million barrels of crude oil. Development has been achieved utilizing an innovative remote subsea system, connected to the Tartan Platform 7½ miles to the southeast.

The Evolution of the Popocatépetl Volcanic Complex: Constraints on Periodic Edifice Construction and Destruction by Sector Collapse

2021 ◽  
pp. jgs2021-022
Author(s):  
Guillem Gisbert ◽  
Hugo Delgado-Granados ◽  
Martin Mangler ◽  
Julie Prytulak ◽  
Ramón Espinasa-Pereña ◽  
...  
Keyword(s):  
Aerial Imagery ◽  
Volcanic Complex ◽  
Sector Collapse ◽  
Content Type ◽  
Digital Elevation ◽  
History Of ◽  
Supplementary Material ◽  
Complex Constraints ◽  
Elevation Model ◽  
First Time

Popocatépetl is one of the most active volcanoes in North America. Its current predominantly mild activity is contrasted by a history of large effusive and explosive eruptions and sector collapse events, which was first summarised by Espinasa-Pereña and Martin-Del Pozzo (2006). Since then, a wealth of new radiometric, geophysical and volcanological data has been published, requiring a re-evaluation of the evolution of the Popocatépetl Volcanic Complex (PVC). Herein, we combine existing literature with new field observations, aerial imagery and digital elevation model interpretations to produce an updated and improved reconstruction of the growth and evolution of the PVC through all of its history. This will be fundamental for the assessment and mitigation of risks associated with potential future high-magnitude activity of the PVC. The PVC consists of four successive volcanic edifices separated by three sector collapse events producing avalanche deposits: Tlamacas (>538 - >330 ka, described here for the first time), Nexpayantla (∼330 - >96 ka), Ventorrillo (∼96 ka - 23.5 ka) and Popocatépetl (<23.5ka) edifices. The newly described Tlamacas collapse propagated towards ENE forming part of the Mayorazgo avalanche deposit.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5709190

scholarly journals Biostratigraphic partition of the Upper Jurassic and Lower Cretaceous (Oxfordian - Lower Berriasian) deposits of the Crimean Mountains for foraminiphers

2018 ◽  
Keyword(s):  
Lower Cretaceous ◽  
Upper Jurassic ◽  
Lower Zone ◽  
Crimean Mountains ◽  
Lower Upper ◽  
Characteristic Features ◽  
Lower Berriasian ◽  
Cretaceous Deposits ◽  
Lower Kimmeridgian

Introduction. Upper Jurassic and Lower Cretaceous deposits in the Crimean Mountains are widespread and are represented by all stages ‑ Oxfordian, Kimmeridgian, Tithonian, and Berriasian. These deposits have been unevenly studied. The most studied deposits are the Oxfordian, Tithonianian and Berriasian stages. The biostratigraphic division of the Upper Jurassic and Lower Cretaceous deposits of the Mountain Crimea is based on "Stratigraphic scheme of the Upper Jurassic and Lower Cretaceous deposits of the Mountain Crimea" 2013. Purpose. Detailed biostratigraphic devision of the Upper Jurassic and Lower Cretaceous (Oxfordian ‑ Lower Berriasian) of the Mountain Crimea as results of foraminiferal analysis. Results of the study. There are five foraminiferal complexes in sections that characterize Upper Jurassic (Lower Upper Oxfordian, Lower Kimmeridgian, Upper Tithonian) and Lower Cretaceous (Lower Berriasian) age. Analysis of foraminiferal complexes allowed us to establish biostratigraphical zones in each section: oxfordiana in the Lower Oxfordian Lenticulina quenstedti-Globuligerina; in the Upper Oxfordian Lenticulina russiensis-Epistomina uhligi; in the Upper Tithonian Anchispirocyclina lusitanica-Melathrokerion spirialis; in the Lower Berriasian (lower zone) Protopeneroplis ultragranulatus-Siphoninella antiqua and layers in the Lower Kimmeridgian with Epistomina praetatariensis-Globuligerina parva. Specified foraminiferal zones were traced by us in different structural-facial zones (zone Lenticulina quenstedti-Globuligerina oxfordiana ‑ in Sudak-Feodosia; zone Lenticulina russiensis-Epistomina uhligi ‑ in Ai-Petri-Babugansk and Sudak-Feodosia; strata layers with Epistomina praetatariensis-Globuligerina parva ‑ in Sudak-Feodosia; zone Anchispirocyclina lusitanica-Melathrokerion spirialis ‑ in Sukhorychensk-Baidar, Demerdzhi-Karabijskaya and Sudak-Feodosiya; the zone of Protopeneroplis ultragranulatus-Siphoninella antiqua in Demerdzhi-Karabijskaya and Sudak-Feodosiya). Characteristic features of each foraminiferа zone include a complex of species, disappearing species, and species that continue to exist, as well as particular features of the complexes. According to lithological peculiarities and paleontological characteristics, suite and sub suite are defined. Conclusions. As a result of the study, the biostratigraphic characteristics of the sections have been specified and the paleontological characteristics of the Upper Jurassic and Lower Cretaceous deposits of the Mountain Crimea have been supplemented.

Lusitanisuchus, a new generic name for Lisboasaurus mitracostatus (Crocodylomorpha: Mesoeucrocodylia), with a description of new remains from the Upper Jurassic (Kimmeridgian) and Lower Cretaceous (Berriasian) of Portugal

2004 ◽  
Vol 41 (10) ◽  
pp. 1259-1271 ◽  
Author(s):  
Daniela Schwarz ◽  
Regina Fechner
Keyword(s):  
Early Cretaceous ◽  
Lower Cretaceous ◽  
Upper Jurassic ◽  
Skull Reconstruction ◽  
First Time ◽  
Lusitanian Basin

Lusitanisuchus mitracostatus is a small mesoeucrocodilian crocodylomorph from the Upper Jurassic (Kimmeridgian) of Guimarota–Leiria in Portugal, which was originally described as an anguimorph lizard (Lisboasaurus mitracostatus Seiffert, 1970) based on jaw fragments and isolated teeth. A recent reexamination of the crocodylomorph material of Guimarota yielded new skull and dentary remains assignable to Lusitanisuchus mitracostatus. The new skull material not only enables for the first time a skull reconstruction of this taxon, but also leads to renaming and reclassifying Lisboasaurus mitracostatus. Teeth of Lusitanisuchus are also reported from the locality Porto Dinheiro–Lourinhã, Early Cretaceous (Berriasian) of Portugal. The presence of this crocodylomorph taxon in two Portuguese localities suggests its occurence in the Lusitanian Basin during the Kimmeridgian to the Berriasian.

scholarly journals New palynological data for Toarcian (Lower Jurassic) deep-marine sandstones of the Western Caucasus, southwestern Russia

Geologos ◽  
2018 ◽  
Vol 24 (2) ◽  
pp. 127-136 ◽  
Author(s):  
Anna A. Goryacheva ◽  
Svetlana O. Zorina ◽  
Dmitry A. Ruban ◽  
Alexei A. Eskin ◽  
Konstantin I. Nikashin ◽  
...  
Keyword(s):  
International Research ◽  
Lower Jurassic ◽  
Research Community ◽  
Dinoflagellate Cysts ◽  
Western Caucasus ◽  
Greater Caucasus ◽  
Palynological Data ◽  
The Western Caucasus ◽  
First Time

Abstract Information on Jurassic palynomorphs from the Greater Caucasus is potentially of great importance, but its availability to the international research community is severely limited. New palynological data for Toarcian deposits of the Western Caucasus are recorded in the present paper. Particularly, dinoflagellate cysts are described for the first time from the Bagovskaja Formation; palynomorphs are found in sandstone levels within this unit. The most representative assemblage includes pollen (with predominant bisaccate pollen), spores (Cyathidites being commonest), and dinoflagellate cysts amongst which the predominant taxon is Nannoceratopsis spiculata. The dinocyst assemblage implies a late Toarcian age for the upper part of the Bagovskaja Formation. On the basis of these new palynostratigraphical results, the range of the formation is extended; previously, only the lower part had been dated on ammonite evidence.

Rare bryozoans from the Gault Clay Formation (Lower Cretaceous, upper Albian) of Kent, England

2020 ◽  
Vol 296 (1) ◽  
pp. 201-209
Author(s):  
Paul D. Taylor
Keyword(s):  
Early Cretaceous ◽  
Late Cretaceous ◽  
Lower Cretaceous ◽  
Spiral Pattern ◽  
Southern England ◽  
Vertical Walls ◽  
Clay Formation ◽  
First Time

Relatively few bryozoans have been recorded to date from the Gault Clay Formation of southern England, yet the Albian (late Early Cretaceous) age of this unit makes it potentially of importance in understanding the roots of the major radiations of cheilostome and cyclostome bryozoans during the Late Cretaceous. Two bryozoan genera are here described for the first time from the Gault Clay on the basis of single specimens from the upper part of this unit at Paddlesworth (Kent), recently discovered in the collection of the late Joe Collins. A colony of the cheilostome Wawalia crenulata that preserves the putative ancestrula reveals two novel features: a spiral pattern of early budding and the presence of pyrite-filled lacunae in the thick vertical walls of the zooids. The second bryozoan is a branch fragment of the erect eleid cyclostome genus Biforicula. Representing the oldest record of this genus, it is described as Biforicula collinsi sp. nov.

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