Faunal dynamics of foraminiferal assemblages in the Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland

2012 ◽  
Vol 62 (3) ◽  
pp. 403-419 ◽  
Author(s):  
Jolanta Smoleń
Keyword(s):  
Sedimentation Rate ◽  
Middle Jurassic ◽  
Taxonomic Diversity ◽  
Feeding Strategies ◽  
Type I ◽  
Type Ii ◽  
Low Oxygen ◽  
Sedimentary Environments ◽  
South Central ◽  
Bottom Waters

ABSTRACT Smoleń, J. 2012. Faunal dynamics of foraminiferal assemblages in the Bathonian (Middle Jurassic) ore-bearing clays at Gnaszyn, Kraków-Silesia Homocline, Poland. Acta Geologica Polonica, 62(3), 403-419. Warszawa. The faunal dynamics of benthic foraminifera in the Middle Jurassic ore-bearing clays of Gnaszyn (Kraków- Częstochowa Upland, south-central Poland) are used to reconstruct sedimentary environments. Two types of foraminiferal assemblages, distinct in their quantitative and qualitative composition, were distinguished; type I assemblages, characterizing intervals between horizons with sideritic concretions; and type II assemblages, characterising horizons with sideritic concretions. Benthic foraminifers were further subdivided into eight ecological morphogroups, based on their morphological features and micro-habitats. Type I assemblages consist mostly of plano/concavo-convex, small-sized epifaunal morphotypes, with a restricted occurrence of shallow infaunal forms and a scarcity of deep infaunal taxa, which suggests low-oxygen conditions in both sediment and bottom waters, and a high sedimentation rate in an outer shelf environment. Type II assemblages are characterized by high taxonomic diversity, high specimen abundance and variability of epifaunal and infaunal morphotypes representing a mixed group of specialized feeding strategies. This suggests optimum living conditions controlled by a lower sedimentation rate, relatively well-oxygenated bottom waters and sufficient or high food supply.

scholarly journals PETROLEUM POTENTIALITY AND PETROPHYSICAL EVALUATION OF THE MIDDLE-JURASSIC SARGELU FORMATION, NORTHERN IRAQ

2020 ◽  
Vol 53 (2D) ◽  
pp. 77-93
Author(s):  
Wrya Mamaseni
Keyword(s):  
Middle Jurassic ◽  
Vitrinite Reflectance ◽  
Black Shales ◽  
Type Ii ◽  
Low Oxygen ◽  
Reservoir Properties ◽  
Organic Matter Quality ◽  
High Hydrogen ◽  
Log Data ◽  
Northern Iraq

This study indicates the source rock evaluation and reservoir properties of the Middle-Jurassic Sargelu Formation in two selected sections (well Atrush-3 and Warte outcrop) northern Iraq. The well log data display that the shale includes 30% of the upper part of the Sargelu Formation. This extraordinary ratio of shale content has negative impacts on the reservoir properties in this part of the formation. The lower part of the formation has a good porosity ratio that reaches 15% as calculated from the log data. The porosity is obtained from analyzed core samples support the same conclusion that obtained in the log data analysis and it is measured at 9-17.5% for interval 1282-1301 m in Atrush-3 well and 5-7.9% in the interval 54-75 m Warte section. The formation has very good organic matter quality for black shales as the average total organic carbon (TOC) measured from the pyrolysis assessments is about 2.61 wt% in both the well and the section. The low oxygen index (average 26 mg CO2/g TOC) and high hydrogen index (average 423 mg HC/g TOC) indicate the variation of the kerogen class from type II in the Atrush-3 to type II-III in the Warte section. These two forms of kerogen can produce oil and condensate gas in a suitable state. Pristine/phytane (Pr/Ph) ratios are less than one (0.67-0.83) and this reveals the anoxic condition for the formation. The colors of the palynomorphs in the examined samples under the microscope changes from yellowish brown to brown (TAI=+2, -3), and the average Tmax and vitrinite reflectance are 444 oC and 0.80, respectively. Sargelu Formation is located within the mature and oil window. This is also supported by the carbon preference index which is around one (average 0.98).

Neogene Metasomatism in the Subcontinental Lithosphere beneath SE Asia—Evidence from Modal and Cryptic Phosphorus Enrichment in Peridotites and Pyroxenites from Southern Laos

2019 ◽  
Vol 60 (12) ◽  
pp. 2413-2448 ◽  
Author(s):  
Jürgen Konzett ◽  
Christoph Hauzenberger ◽  
Kurt Krenn ◽  
Bastian Joachim-Mrosko ◽  
Roland Stalder ◽  
...  
Keyword(s):  
Oscillatory Zoning ◽  
Type I ◽  
Carbonate Apatite ◽  
Type Ii ◽  
Secular Evolution ◽  
Rock Types ◽  
South Central ◽  
Calcic Amphibole ◽  
Component Type ◽  
Basaltic Melts

Abstract Metasomatism is the prime process to create compositional heterogeneity of the upper mantle. Mineralogical and mineral chemical changes of the mantle triggered by metasomatism can be used to deduce the nature of the metasomatic agent(s) and to constrain the timing of metasomatism. This information is vital for an understanding of the secular evolution of a given mantle segment and the magmatic processes occurring therein. For this study spinel-lherzolites and -websterites were collected from ∼16 Myr old alkali-basaltic lava flows that were extruded on the Bolaven Plateau in south–central Laos. These xenoliths are fragments of the shallow continental lithosphere of the SE Asian peninsula and originate from a mantle segment that acted as source for Cenozoic basaltic volcanism in the wake of the India–Asia collision. In both rock types modal metasomatism formed apatite ± whitlockite ± phlogopite ± calcic amphibole ± calcite ± orthopyroxene. The principal metasomatic phase is apatite, which appears in three varieties. Type-I apatite is ±inclusion-free and associated with phlogopite, calcic amphibole, calcite and lamellar orthopyroxene. It is high in Na and low in P and shows low analytical totals indicating a type-B carbonate–apatite component. Type-I apatite presumably precipitated from a P-alkali-rich mixed H2O–CO2 fluid with low large ion lithophile element (LILE)–light rare earth element (LREE) contents. Type-II apatite shows a spongy texture and has lower Na and higher P contents with higher analytical totals. Crosscutting discontinuous zones of type-II characteristics within type-I apatites indicate type-II formation through an exchange Na+ + CO32– = PO43– + Ca2+ by a later fluid with lower aCO2. REE-rich type-III apatite is the youngest type and formed by infiltration of basaltic melts as part of spongy rims around clinopyroxene. One lherzolite contains whitlockite in addition to apatite. Whitlockite formation is ascribed to a short-lived metasomatic event involving a fluid with extremely low aH2O. Disequilibrium between whitlockite and the bulk assemblage is indicated by hydrous silicates in the immediate vicinity of whitlockite and by substantial H2O contents of 250–370 µg g–1 in clinopyroxenes and 170–190 µg g–1 in orthopyroxenes. High-density (1·15–≥1·17 g m–3) CO2–fluid inclusions in the whitlockite-bearing sample provide evidence for the presence of low-aH2O fluids at mantle depths. The spinel-herzolites may also show cryptic metasomatism evidenced by P zoning in olivine, which is characterized by P-poor (<20–130 µg g–1) cores and P-rich (170–507 µg g–1) rims, the latter in part with oscillatory zoning on a µm scale. Element correlations indicate [4]Si4+ + [6](Mg, Fe)2+ = [4]P5+ + [6]Li+, 2 [4]Si4+ + 4 [6](Mg, Fe)2+ = 2 [4]P5+ + 3 [6](Mg, Fe)2+ + [6]vac and/or 5 [4]Si4+ = 4 [4]P5+ + [4]vac as major P incorporation mechanisms. High P–T experiments conducted at 2 GPa and 950–1050 °C yield apatite-saturated P contents of olivine in the range ∼360–470 µg g–1. Most P concentrations in olivines from the xenoliths including those in the P-rich rims, however, are significantly lower than the apatite-saturated values, which indicates disequilibrium uptake of P during growth of the P-rich rims by dissolution–reprecipitation. Diffusion modeling indicates that the P zoning must have formed within decades prior to the eruption of the host basalts. This is consistent with the preservation of Li disequilibrium partitioning between olivine and pyroxenes in some of the xenoliths. All metasomatic phenomena were assigned to two metasomatic events, both of which were in close temporal relation with the eruption of the xenolith host basalts: an older event-1 formed type-I apatite, hydrous silicates, calcite and orthopyroxene and caused the modification of type-I apatite composition towards that of type-II. It is also likely to be responsible for whitlockite formation and P zoning in olivine. A younger event-2 comprises all paragenetic, textural and compositional modifications of the xenolith assemblages associated with the infiltration of basaltic melts.

scholarly journals Foraminiferal stratigraphy and palaeoecological implications in turbidite-like deposits from the Early Tortonian (Late Miocene) of Greece

2007 ◽  
Vol 26 (2) ◽  
pp. 145-158 ◽  
Author(s):  
H. Drinia ◽  
A. Antonarakou ◽  
N. Tsaparas ◽  
M. D. Dermitzakis
Keyword(s):  
Habitat Preferences ◽  
High Energy ◽  
Environmental Stability ◽  
Ecological Niches ◽  
Feeding Strategies ◽  
Sedimentary Environments ◽  
Bottom Waters ◽  
Broad Variety ◽  
Consistent Picture ◽  
Of Greece

Abstract. The Lower Tortonian Ag. Giannis section, in Gavdos Island, Greece, consists of an outer neritic to upper bathyal, marly hemipelagic sequence which is interrupted by thick turbidite-like sandy deposits. During deposition of the marly intervals, reworking was considerably reduced.This paper contributes to knowledge concerning benthic foraminiferal response to dynamic sedimentary environments. Important palaeoecological information for benthic foraminiferal assemblages was gathered and analyzed in order to create a regionally consistent picture of the palaeoenvironment. Samples were analyzed statistically in order to identify the different palaeoenvironmental settings during turbiditic sedimentation. Undisturbed basal marls of the section are characterized by the predominance of a diversified Uvigerina striatissima assemblage typified by a broad variety of morphotypes with different inferred habitat preferences and feeding strategies, indicating rather well-oxygenated bottom waters. This environmental stability was subsequently disrupted by recurrent deposition of turbidite-like sands. A low-diversity Valvulineria complanata-Globobulimina sp. assemblage is dominant in this part of the succession, as these specialized endobenthic species could keep pace with high-energy sedimentary settings. Just above the turbidites, a “recolonization” fauna (Bolivina alata assemblage), composed entirely of infaunal elements is observed, indicating a nutrient-rich substrate. This oligotypic fauna is later replaced by a more diversified microfauna capable of occupying a wider range of ecological niches.

Heat-Etching with a Bullivant Type II Simple Freeze-Cleave Device

1970 ◽  
Vol 28 ◽  
pp. 106-107 ◽  
Author(s):  
Ronald S. Weinstein ◽  
N. Scott McNutt
Keyword(s):  
New Zealand ◽  
General Hospital ◽  
Massachusetts General Hospital ◽  
Type I ◽  
Type Ii ◽  
Collaborative Effort ◽  
Temperature And Pressure ◽  
The University

The Type I simple cold block device was described by Bullivant and Ames in 1966 and represented the product of the first successful effort to simplify the equipment required to do sophisticated freeze-cleave techniques. Bullivant, Weinstein and Someda described the Type II device which is a modification of the Type I device and was developed as a collaborative effort at the Massachusetts General Hospital and the University of Auckland, New Zealand. The modifications reduced specimen contamination and provided controlled specimen warming for heat-etching of fracture faces. We have now tested the Mass. General Hospital version of the Type II device (called the “Type II-MGH device”) on a wide variety of biological specimens and have established temperature and pressure curves for routine heat-etching with the device.

Labelling of non-A, non-B hepatitis infected chimpanzee hepatocytes with nuclease-gold conjugates

1984 ◽  
Vol 42 ◽  
pp. 250-251
Author(s):  
G. D. Gagne ◽  
M. F. Miller ◽  
D. A. Peterson
Keyword(s):  
Endoplasmic Reticulum ◽  
Experimental Infection ◽  
Uranyl Acetate ◽  
Type I ◽  
Cellular Injury ◽  
Type Ii ◽  
Tubular Structures ◽  
Type Iii ◽  
Type Iv ◽  
Infected Chimpanzee

Experimental infection of chimpanzees with non-A, non-B hepatitis (NANB) or with delta agent hepatitis results in the appearance of characteristic cytoplasmic alterations in the hepatocytes. These alterations include spongelike inclusions (Type I), attached convoluted membranes (Type II), tubular structures (Type III), and microtubular aggregates (Type IV) (Fig. 1). Type I, II and III structures are, by association, believed to be derived from endoplasmic reticulum and may be morphogenetically related. Type IV structures are generally observed free in the cytoplasm but sometimes in the vicinity of type III structures. It is not known whether these structures are somehow involved in the replication and/or assembly of the putative NANB virus or whether they are simply nonspecific responses to cellular injury. When treated with uranyl acetate, type I, II and III structures stain intensely as if they might contain nucleic acids. If these structures do correspond to intermediates in the replication of a virus, one might expect them to contain DNA or RNA and the present study was undertaken to explore this possibility.

Comparative surface and ultrastructural views of methylotrophic bacteria by TEM, STEM, SE, and freeze-etch electron microscopy.

1987 ◽  
Vol 45 ◽  
pp. 792-793
Author(s):  
T.A. Fassel ◽  
M.J. Schaller ◽  
M.E. Lidstrom ◽  
C.C. Remsen
Keyword(s):  
Cytoplasmic Membrane ◽  
Structural Features ◽  
Methylotrophic Bacteria ◽  
Type I ◽  
Type Ii ◽  
Membrane Complex ◽  
Oxidation Of Methane ◽  
Methane Oxidizing Bacteria ◽  
Wall Structures ◽  
Methylomonas Albus

Methylotrophic bacteria play an Important role in the environment in the oxidation of methane and methanol. Extensive intracytoplasmic membranes (ICM) have been associated with the oxidation processes in methylotrophs and chemolithotrophic bacteria. Classification on the basis of ICM arrangement distinguishes 2 types of methylotrophs. Bundles or vesicular stacks of ICM located away from the cytoplasmic membrane and extending into the cytoplasm are present in Type I methylotrophs. In Type II methylotrophs, the ICM form pairs of peripheral membranes located parallel to the cytoplasmic membrane. Complex cell wall structures of tightly packed cup-shaped subunits have been described in strains of marine and freshwater phototrophic sulfur bacteria and several strains of methane oxidizing bacteria. We examined the ultrastructure of the methylotrophs with particular view of the ICM and surface structural features, between representatives of the Type I Methylomonas albus (BG8), and Type II Methylosinus trichosporium (OB-36).

OPTICAL STUDIES OF TYPE I AND TYPE II RECOMBINATION IN GaAs-AlAs QUANTUM WELLS

1987 ◽  
Vol 48 (C5) ◽  
pp. C5-525-C5-528 ◽  
Author(s):  
K. J. MOORE ◽  
P. DAWSON ◽  
C. T. FOXON
Keyword(s):  
Quantum Wells ◽  
Type I ◽  
Type Ii ◽  
Optical Studies

An old friend is better than two new ones? Approaches to market research in the context of digital transformation for the antitrust laws enforcement

2020 ◽  
pp. 37-55 ◽  
Author(s):  
A. E. Shastitko ◽  
O. A. Markova
Keyword(s):  
Business Models ◽  
Rapid Development ◽  
Digital Transformation ◽  
Market Definition ◽  
Type I ◽  
Type Ii ◽  
Digital Platforms ◽  
Advantages And Disadvantages ◽  
Pass Through ◽  
Type Ii Errors

Digital transformation has led to changes in business models of traditional players in the existing markets. What is more, new entrants and new markets appeared, in particular platforms and multisided markets. The emergence and rapid development of platforms are caused primarily by the existence of so called indirect network externalities. Regarding to this, a question arises of whether the existing instruments of competition law enforcement and market analysis are still relevant when analyzing markets with digital platforms? This paper aims at discussing advantages and disadvantages of using various tools to define markets with platforms. In particular, we define the features of the SSNIP test when being applyed to markets with platforms. Furthermore, we analyze adjustment in tests for platform market definition in terms of possible type I and type II errors. All in all, it turns out that to reduce the likelihood of type I and type II errors while applying market definition technique to markets with platforms one should consider the type of platform analyzed: transaction platforms without pass-through and non-transaction matching platforms should be tackled as players in a multisided market, whereas non-transaction platforms should be analyzed as players in several interrelated markets. However, if the platform is allowed to adjust prices, there emerges additional challenge that the regulator and companies may manipulate the results of SSNIP test by applying different models of competition.

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