Middle–Upper Jurassic (Upper Callovian–Lower Kimmeridgian) stable isotope and elemental records of the Russian Platform: Indices of oceanographic and climatic changes

2013 ◽  
Vol 107 ◽  
pp. 196-212 ◽  
Author(s):  
Hubert Wierzbowski ◽  
Mikhail A. Rogov ◽  
Bronisław A. Matyja ◽  
Dmitry Kiselev ◽  
Alexei Ippolitov
Keyword(s):  
Stable Isotope ◽  
Upper Jurassic ◽  
Climatic Changes ◽  
Russian Platform ◽  
Upper Callovian ◽  
Lower Kimmeridgian

MIDDLE – UPPER JURASSIC (UPPER CALLOVIAN TO LOWER KIMMERIDGIAN) CARBON ISOTOPE CHEMOSTRATIGRAPHY FROM CENTRAL SAUDI ARABIA

2016 ◽  
Author(s):  
Hassan Eltom ◽  
◽  
Luis A. Gonzalez ◽  
Eugene C. Rankey ◽  
Stephen T. Hasiotis ◽  
...  
Keyword(s):  
Saudi Arabia ◽  
Carbon Isotope ◽  
Upper Jurassic ◽  
Upper Callovian ◽  
Lower Kimmeridgian

A revision of the rare genusCyclolampas(Echinoidea) using morphometrics with description of a new species from the upper Callovian of Burgundy (France)

2013 ◽  
Vol 87 (1) ◽  
pp. 105-122 ◽  
Author(s):  
Thomas Saucede ◽  
Alain Bonnot ◽  
Didier Marchand ◽  
Philippe Courville
Keyword(s):  
New Species ◽  
Upper Jurassic ◽  
Systematic Position ◽  
Linear Measurements ◽  
Systematic Revision ◽  
Fourier Shape Analysis ◽  
And Migration ◽  
A New Species ◽  
Upper Callovian ◽  
Test Shape

The discovery of a new species,Cyclolampas altusnew species in the upper Callovian of Burgundy (France) leads to the systematic revision of the rare echinoid genusCyclolampasPomel, 1883. Two morphometric approaches are used jointly to describe and quantify variations in test shape: the analysis of linear measurements and the Elliptic Fourier shape analysis. Both analyses yield congruent results that highlight the amplitude of within-species variations and quantify the part due to allometry. Along with the description ofC. altus, the systematic position of species formerly assigned to the generaPygorhytisPomel, 1883 andCyclolampasis amended. Previously attributed to the genusPygorhytis,Cyclolampas castanea(Desor, 1858) is reassigned to the genusCyclolampason the base of new observations. Conversely, the examination of the Bajocian speciesPygorhytis kiliani(Lambert, 1909) andPygorhytis gillieroniDesor in Desor and de Loriol, 1872, which were previously assigned toCyclolampasnow supports their taxonomic reassignment to the genusPygorhytis. Finally, the two speciesCyclolampas verneuili(Cotteau, 1870) andCyclolampas cotteauiMintz, 1966 (nomen nudum) are considered junior synonyms of the genus type speciesCyclolampas voltzii(Agassiz, 1839). The questioned origin date of the genus, estimated either to the Bajocian or to the Oxfordian, is now clearly established to be upper Callovian. These new results fit well with the overall scheme of atelostomate echinoid evolution and migration to deep-sea environments during the Middle and Upper Jurassic.

Sur la presence de dolomite dans les 'terres noires' de l'anticlinorium de Laragne (Hautes-Alpes); interpretation paleo-oceanographique

1965 ◽  
Vol S7-VII (5) ◽  
pp. 769-772
Author(s):  
Philippe Artru
Keyword(s):  
Middle Jurassic ◽  
Upper Jurassic ◽  
Low Ph ◽  
Dolomite Formation ◽  
Upper Callovian ◽  
Lower Bathonian

Abstract Middle Jurassic (Bathonian) and upper Jurassic (Callovian-lower Argovian) dark-colored shales and marls of Hautes-Alpes, France, locally known as the 'terres noires,' contain abundant microcrystalline dolomite in the lower (Bathonian) part. Mixed detrital sediments and carbonates in the lower part contrast with essentially terrigenous strata in the upper (Callovian-Oxfordian) part. The Bathonian depositional basin was isolated by sills and probably contained magnesium-rich waters of low pH; at the beginning of the upper Jurassic the basin became more open and dolomite formation ceased.

Late Barremian–early Aptian climate of the northern middle latitudes: Stable isotope evidence from bivalve and cephalopod molluscs of the Russian Platform

2013 ◽  
Vol 44 ◽  
pp. 183-201 ◽  
Author(s):  
Yuri D. Zakharov ◽  
Eugenij Y. Baraboshkin ◽  
Helmut Weissert ◽  
Irina A. Michailova ◽  
Olga P. Smyshlyaeva ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Russian Platform ◽  
Middle Latitudes ◽  
Isotope Evidence

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.

scholarly journals A Flow Model and a Time Scale for the Ice Core from Camp Century, Greenland

1969 ◽  
Vol 8 (53) ◽  
pp. 215-223 ◽  
Author(s):  
W. Dansgaard ◽  
S. J. Johnsen
Keyword(s):  
Steady State ◽  
Stable Isotope ◽  
Time Scale ◽  
Flow Model ◽  
Ice Core ◽  
Climatic Changes ◽  
Horizontal Velocity ◽  
Measured Temperature ◽  
The Core ◽  
Vertical Strain

A flow model is described for the Camp Century area in Greenland. The horizontal velocity profile along the core is assumed to be uniform from the surface down to y = 400 m above the bottom. Below this level, the horizontal velocity vx, is assumed to decrease proportionally to y. Furthermore, at a given y, vx is assumed to be proportional to the distance x from the ice divide. The resulting vertical strain-rate under steady-state conditions gives the age of the ice as a function of y. The flow model has explained the measured temperature profile, and the time scale has been verified by comparison between observed stable isotope variations and past climatic changes (at least 70 000 years back in time) estimated by other methods.

THE KIMMERIDGIAN MARL IN THE TIMOR SEA: RELEVANCE TO REGIONAL GEOLOGICAL EVOLUTION AND POSSIBLE HYDROCARBON PLAYS

1995 ◽  
Vol 35 (1) ◽  
pp. 152
Author(s):  
J. D. Gorter ◽  
A.S. Kirk
Keyword(s):  
Upper Jurassic ◽  
Secondary Porosity ◽  
Condensed Section ◽  
Timor Sea ◽  
Time Structures ◽  
Sequence Boundaries ◽  
Shelf Margin ◽  
Tectonic Movements ◽  
Lower Kimmeridgian

Lower Kimmeridgian marls in the Sahul Syncline have a distinct seismic character and can be used to define the limits of depocentres, but the reflector is difficult to map in the Vulcan Sub-basin. The top of the carbonate is an unconformity in shelfal areas and on uplifted structures, but in the depocentres, where a distinctive and thin limestone is present at the top of the marls, there is no evidence of missing section. The limestone, which is interpreted to reflect the paraconformity of the 139 Ma Type 1 sequence boundary, consists of the amalgamated condensed highstand overlying the 139.5 Ma condensed section, and the condensed transgressive systems tract of the overlying C. perforans shelf margin wedge.The underlying Upper Jurassic section is an important source interval in the Vulcan Sub-basin and the regional extent of the reflector may approximate the area in which Oxfordian source beds were deposited. Regional isochore mapping may also delineate areas of potential silled, fault-bounded depocentres within the greater Sahul Syncline that were in existence during latest Callovian to early Kimmeridgian time. Structures located within the fetch of these depocentres should be ideally placed to trap migrating hydrocarbons sourced from restricted marine shales of Oxfordian age.Erosion accompanying the 138 Ma lowstand has removed some or all of the marls and the C. perforans sediments from structures uplifted during the contemporaneous mid-Kimmeridgian tectonism. Major sea level falls, probably also associated with tectonic movements at the 136, 135 and 134 Ma sequence boundaries, could have led to further erosion or non-deposition on high blocks. Given sufficient time and suitable lithology, fresh water diagenesis and leaching of these marls may have led to the development of secondary porosity with later sealing by post-Kimmeridgian shales, especially where the interval contains coarser clastics as along the flank of the Flamingo High.

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