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Historia pierwszej w Warszawie pracowni mikropaleontologicznej

Gawor-Biedowa Eugenia

Przegląd Geologiczny

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2020

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Vol. 68, nr 5

449--460

EN

Micropalaeontological Laboratory at the Polish Geological Institute in Warsaw was organized by Władysław Pożaryski in 1947. The studies were going towards the development of regional micropalaeontological stratigraphic schemes of Mesozoic deposits of Poland (excluding the Carpathians) and dating rocks, based on micropalaeontological analyses. Results of examination of a huge number of samples (over 90,000) have been the basis for biostratigraphical reports and monographs, diagnoses of many new taxa, and over 1000 archival collections of Mesozoic, Paleogene and Neogene microfaunas. The golden era of the Laboratory had lasted almost four decades.

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The position and age of flysch deposits in the Crimean Mountains (Southern Ukraine)

Oszczypko N., Ślączka A., Bubniak I., Olszewska B., Garecka M.

Geological Quarterly

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2017

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Vol. 61, No. 4

697--722

EN

The Crimean Mountains (CM) are regarded as part of the Alpine-Himalaya orogenic belt related to the collision of the Eurasian and African plates. Our research in the CM has allowed confirming the existence of at least two flysch formations of different ages: the Taurida Flysch Formation (Upper Triassic/Lower–? Middle Jurassic) and the Sudak Formation (uppermost Jurassic/Lower Cretaceous) in the western and eastern sectors of the CM, respectively. After the Middle Jurassic volcanism, the freshwater claystones with coal-bearing intercalations, as well as local alluvial fan conglomerates were deposited. Then, following the Oxfordian/Kimmeridgian marine transgression, three separated Tithonian/Berriasian carbonate platforms developed: Baydarska, Chatyr-Dag and Demerji/Karabi. At the turn of the Late Jurassic, the deep-water Sudak Basin (eastern sector of the CM) began to develop in the eastern periphery of the Demerji/Karabi carbonate platform. This basin, dominated by turbiditic deposition, was probably connected with the Great Caucasus sedimentary system. Finally, distal flysch sedimentation in the Sudak Basin was followed by debris-flow deposits, with huge blocks of Upper Jurassic limestones. These blocks were derived from destruction of the Karabi carbonate platform. During the Berriasian/Valanginian, the eastern sector of the CM began to subside. As a result, both carbonate platforms (western CM) and the debris flow fans of the Sudak Basin (eastern CM) were overlain by marly shales and/or distal turbidites. This type of deposition lasted until the Aptian/Albian. In the post-Albian period, the Alushta-Salgir tectonic zone was transformed into a SE-dipping thrust fault with at least 10 km amplitude of overthrusting.

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Towards an integrated Jurassic biostratigraphy for eastern Greenland

Kelly S. R. A., Gregory F. J., Braham W., Strogen D. P., Whitham A. G.

Volumina Jurassica

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2015

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Vol. 13, no. 1

43--64

EN

The thick and relatively complete Jurassic succession of eastern Greenland provides a unique biostratigraphic record for the North Atlantic region. The main biostratigraphic control for the succession has been provided by molluscs, especially ammonites and to a lesser extent by bivalves and belemnites. The late John Callomon and colleagues recognised 93 Boreal ammonite-bearing horizons in the Mid to Late Jurassic. This provides a reliable backbone to the biostratigraphy of these strata, prompting a palynological colleague to comment that they are the “Policemen of Jurassic Stratigraphy”. Other biostratigraphically significant microfossil and palynological groups, can be calibrated against this standard, but on their own cannot achieve the same precision. The Early Jurassic of eastern Greenland does not have such fine control as later parts of the period. No single biostratigraphic group can be used successfully throughout the interval, and there are only three significant ammonite faunas during this period. Reliance on various different organisms is necessary to cope with the changing range of marine to non-marine environments. CASP field-work from 1990 to 2012 has resulted in the collection of much biostratigraphic material. In this article, published data are summarised together with previously unpublished data in the form of a unified table. The integrated chart shows detailed columns for the whole eastern Greenland Jurassic. It demonstrates the ammonite, palynological and microfossil events/biozones and horizons which are correlated by time. More limited information is available on belemnites, bivalves and macroflora. This is the first time such an integrated biostratigraphic scheme has been assembled for the Jurassic of eastern Greenland. It will be of value to the offshore oil-industry in the northern North Atlantic and on the Barents Shelf as well as to field geologists in Greenland.

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Nearness of Sets in Local Admissible Covers : Theory and Application in Micropalaeontology

Peters J.F.

Fundamenta Informaticae

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2013

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Vol. 126, nr 4

433--444

EN

This paper considers the nearness of sets in local descriptive admissible covers of nonempty sets and the problem of quantifying the nearness of such sets. A brief review of descriptive Efremovič spaces as well descriptive intersection and union provides a foundation for the study of descriptive admissible covers. Descriptively near sets in admissible covers contain sequences of points with members having similar descriptions. The motivation for this approach stems from the need to consider fine-grained neighbourhoods of points in admissible covers that facilitate highly accurate measures of nearness of tiny parts of sets of objects of interest. A practical application of local admissible covers is given in terms of micropalaeontology and the detection of minute similarities and differences in microfossils, useful in the study of climate change, mineral and fossil fuel exploration.

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Arthrodendron borberensis sp. nov., a large protist (Foraminifera) from the Pagliaro Formation (Paleocene), Northern Apennines, Italy

Uchman A., Kaminski M. A., Rattazzi B.

Geological Quarterly

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2012

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Vol. 56, No 1

215-224

EN

Arthrodendron borberensis sp. nov. is described from the Pagliaro Formation (Paleocene) of the Northern Apennines. Specimens of the new species are preserved on the sole of a turbiditic sandstone bed. Arthrodendron borberensis sp. nov. is characterized by its long chambers (some exceeding 10 mm in length), its generally straight course, and rare branching at an acute angle. This large foraminifer lived infaunally within the sediment and possibly as epifauna after exhumation by erosion, prior to the deposition of the host turbiditic sandstone bed. Assemblages of smaller agglutinated foraminifera (a flysch-type fauna) and trace fossils (Nereites ichnofacies) point to a deep-sea environment for the discussed protist

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Sedimentological and micropalaeontological evidence to elucidate post-evaporitic carbonate palaeoenvironments of the Saudi Arabian latest Jurassic

Hughes G., Naji N.

Volumina Jurassica

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2008

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Vol. 6, no. 1

61-73

EN

The Hith Formation forms the youngest lithostratigraphic unit of the Jurassic Shaqra Group. It represents the culmination of a succession of hypersaline and euryhaline cycles that characterise the Late Jurassic of Saudi Arabia. The Formation is poorly exposed in central Saudi Arabia, but it has been studied in detail in subsurface eastern Saudi Arabia where the upper carbonate member hosts an important hydrocarbon reservoir called the Manifa Reservoir. Chronostratigraphic control is absent from the formation itself, and the Tithonian age is suggested for the Hith Formation based on its stratigraphic position between the underlying Arab Formation of Late Kimmeridgian age, and the overlying Sulaiy Formation, of Late Tithonian to Berriasian age. The Hith Formation needs redefining in the light of new lithological evidence, and a tripartite member scheme is suggested. This includes the lower anhydrite-dominated member here termed the “anhydrite” member, and considered to represent hypersaline subaqueous deposition within a restricted deep lagoon during the lowstand systems tract of the Manifa sequence. A “transitional“ member consists of interbedded anhydrites and carbonates and approximates with the transgressive zone. The overlying “carbonate” member represents the results of a prograding shallow, normal salinity marine succession related to the highstand systems tract. Interbedded carbonates within the evaporites are interpreted to represent superimposition of a higher frequency, possibly 4th order eustatic cyclicity. The “carbonate“ member hosts the Manifa Reservoir, and here proposed as the Manifa Member, consist of five parasequences, each of which represents a shoaling-upwards cycle with a succession of up to five repeated lithofacies and biofacies that commences with a stromatolitic, microfaunally-barren unit followed by fine-grained grainstones with a monospecific but abundant ostracod biofacies. A succession of coarse pelloidal grainstones with rare foraminifera, including Redmondoides lugeoni, Trocholina alpina with a variety of unidifferentiated valvulinids and miliolids then follows, that passes vertically into coarse ooid grainstones, with rare Redmondoides lugeoni, forming the uppermost part of each parasequence.

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Oxfordian biofacies and palaeoenvironments of Saudi Arabia

Hughes G., Al-Khaled M., Varol O.

Volumina Jurassica

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2008

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Vol. 6, no. 1

47-60

EN

The Hanifa Formation in Saudi Arabia consists of a succession of carbonates, over 100 m thick, that were deposited during the Late Jurassic. It consists of two depositional sequences represented by the lower Hawtah Member and an upper Ulayyah Member, respectively. The Hawtah Member is assigned an Early (?) to Middle Oxfordian age, based on brachiopod, nautiloid and coccolith evidence. The Ulayyah Member is assigned a Late Oxfordian age based on ammonite, nautiloid, coccolith and foraminiferal evidence. Detailed study of the microbiofacies and lithology of the late highstand succession of the Ulayyah sequence in 41 cored wells distributed across the Kingdom was aimed at determining the most suitable locations for porous and permeable grainstone accumulation as lithofacies hosts the Hanifa Reservoir elsewhere in the region. A range of palaeoenvironments has been determined, based on integrated biofacies and lithofacies, that include shallow lagoon packstones and foraminiferal dominated grainstones and deep lagoon wackestones and packstones with Clypeina/Pseudoclypeina dasyclad algae. In addition, a series of basin-margin, shoal-associated biofacies are present that include stromatoporoid back-bank packstones and grainstones with the branched stromatoporoid Cladocoropsis mirabilis, bank-crest grainstones with encrusting and domed stromatoporoids. A few wells also proved the presence of intrashelf basin-flank mudstones and wackestones containing sponge spicules, deep marine foraminifera and coccoliths. This study provided control to delimit an intrashelf basin with an irregular margin situated in the east-central part of the Saudi Arabian portion of the Arabian Plate carbonate platform during Late Oxfordian. The basin is flanked by a belt of stromatoporoid banks that pass laterally into a back-bank facies before developing into a lagoon facies. There is no evidence for the shoreline of this basin, although the presence of rare charophytes in the northwest testifies to possible proximity of fluviatile input. The grainstone dominated basin margin facies presents good hydrocarbon reservoir facies and its juxtaposition to intrashelf basinal sediments with potential source rock character provides exciting new prospects in areas hitherto uninvestigated for hydrocarbon reservoirs.

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Biofacies and palaeoenvironments of the Jurassic Shaqra Group of Saudi Arabia

Hughes G.

Volumina Jurassica

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2006

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Vol. 4, no. 1

89-90

EN

The Jurassic succession in Saudi Arabia consist of eight formations, of which most are carbonate and some are partly evaporitic, and is of economic importance because it hosts twelve hydrocarbon reservoirs, including the Arab-D reservoir within the world’s largest oilfield at Ghawar. The Minjur-Marrat formational boundary marks the Triassic/Jurassic boundary, of which the Marrat is dated as Toarcian. A significant unconformity separates the overlying Dhruma Formation, of Bajocian to Bathonian age. The Tuwaiq Mountain Formation, of Callovian age, overlies the Dhruma Formation, with reduced unconformity duration. The Hanifa Formation, of Oxfordian age, is separated from the Tuwaiq Mountain Formation by a minor unconformity, as are the successive Jubaila, Arab and Hith formations, of Kimmeridgian to Tithonian age. The Jurassic/Cretaceous boundary is currently placed at the Hith-Sulaiy formational contact. Intensive analyses of the carbonates reveals variably rich micropalaeontological biofacies that contain foraminiferal species of potential palaeoenvironmental significance, especially when applied to cored mudstone to grainstone repeated successions of which the hierarchy is often difficult to elucidate. A combination of semi-quantitative micropalaeontological and macropalaeontological analysis of closely-spaced thin sections from these carbonates reveals clearly defined microbiofacies cycles. Their stacking order provides clearly defined palaeoenvironmental trends that subdivide the succession into potential parasequences, transgressive and highstand systems tracts. The Shaqra Group spans at least 38 Ma, and qualifies as a second order depositional sequence, within which the lithostratigraphic units of formation identity fall into third order sequences. The extensive duration of unconformities spanning the Hettangian-Sinemurian and the Aalenian-Bajocian need explaining, especially when compared to the relatively minimal interformational unconformities that characterize the Bajocian-Tithonian succession. Eustatic sea-level data indicates that the Hettangian to Early Pliensbachian is characterized by a relatively insignificant sea level variation when compared with the gradual rise from the Late Bajocian to the Kimmeridgian. The mid Bajocian event approximates with the global increase in percent dolomite in abiotic muds, and may be associated with a transitional icehouse-greenhouse phase, for which post Bajocian eustatic falls would be expected to display increasing greenhouse affinity. Preservation of calcitic ooids within the Middle and Late Jurassic carbonate reservoirs within Saudi Arabia, together with excellent intergranular porosity testify to the calcitic oceanic conditions associated with greenhouse times. The biofacies approach to elucidating palaeoenvironmental variations of the Shaqra Group provides significant insights to the Jurassic history of the Arabian Plate, as well as serving to explain the origin and stratigraphic location of hydrocarbon reservoirs.