Occurrence and significance of smectite in the Pliensbachian (Lower Jurassic) at Lókút (Bakony Mts., Hungary)

AbstractAlthough the Mesozoic rocks of the Transdanubian Range have been the subject of a multitude of different studies, mineralogical research is largely underrepresented. The clay mineralogy of Lower Jurassic (especially the Pliensbachian and Toarcian) strata was broadly investigated earlier; however, systematic high-resolution clay mineralogical studies remain scarce. Here we present a mineralogical study focusing on the Upper Pliensbachian strata of the Lókút-Hosszúárok section, located near the Eplény Manganese Ore Field. We identified dioctahedral smectite, randomly interstratified illite/smectite, illite as 10 Å phyllosilicate, quartz and cristobalite. Based on our new results we propose that the smectite was formed by aging of Mg or Fe hydroxide-silica precipitates. The smectite and cristobalite were presumably formed from the siliceous tests of radiolarians, whose abundance was controlled by a local upwelling system. The occurrence of Pliensbachian smectite in the Lókút outcrop shows similarities with the Úrkút smectites known from both Pliensbachian and Toarcian strata, which implies that similar processes controlled the sedimentation during the Pliensbachian as well as during the black (gray) shale-hosted ore accumulation in the Eplény and Úrkút basins.

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High-Resolution Pixel LED Headlamps: Functional Requirement Analysis and Research Progress

Applied Sciences ◽

10.3390/app11083368 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3368

Author(s):

Liping Wang ◽

Jianshe Ma ◽

Ping Su ◽

Jianwei Huang

Keyword(s):

High Resolution ◽

Functional Diversity ◽

Traffic Safety ◽

New Technologies ◽

Light Distribution ◽

Research Progress ◽

Requirement Analysis ◽

Functional Requirement ◽

Traffic Conditions ◽

The Subject

High-resolution pixel LED headlamps are lighting devices that can produce high-resolution light distribution to adapt to road and traffic conditions, intelligently illuminate traffic areas, and assist drivers. Due to the complexity of roads and traffic conditions, the functional diversity of high-resolution pixel LEDs headlamps and traffic safety has come into question and is the subject of in-depth research conducted by car manufacturers and regulators. We summarize the current possible functions of high-resolution pixel LED headlamps and analyze ways in which they could be improved. This paper also discusses the prospect of new technologies in the future.

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High resolution integrated microbiostratigraphy of the Lower Jurassic (late Pliensbachian–early Toarcian) of central Italy

Journal of Micropalaeontology ◽

10.1144/jm.17.2.153 ◽

1998 ◽

Vol 17 (2) ◽

pp. 153-172 ◽

Cited By ~ 18

Author(s):

Raffaella Bucefalo Palliani ◽

Emanuela Mattioli

Keyword(s):

High Resolution ◽

Evolutionary History ◽

Central Italy ◽

Lower Jurassic ◽

High Potential ◽

Calcareous Nannofossils ◽

Calcareous Nannofossil ◽

Dinoflagellate Cyst ◽

History Of ◽

Global Events

Abstract. The integrated use of calcareous nannofossil and dinoflagellate cyst events in a study of the late Pliensbachian–early Toarcian interval in central Italy has yielded a high resolution biostratigraphy. The use of both the first and last occurrences of selected taxa belonging to the two phytoplankton groups allows the dating of the sediments with a very refined detail, even when lithologies are unfavourable to the preservation of one fossil group. The evolutionary history of calcareous nannofossils and dinoflagellate cysts during the early Jurassic and its links with global events are responsible for the high potential of this integrated biostratigraphy.

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The Impact of Agulhas Leakage on the Central Water Masses in the Benguela Upwelling System From A High‐Resolution Ocean Simulation

Journal of Geophysical Research Oceans ◽

10.1029/2018jc014218 ◽

2018 ◽

Vol 123 (12) ◽

pp. 9416-9428 ◽

Cited By ~ 4

Author(s):

Nele Tim ◽

Eduardo Zorita ◽

Franziska U. Schwarzkopf ◽

Siren Rühs ◽

Kay‐Christian Emeis ◽

...

Keyword(s):

High Resolution ◽

Water Masses ◽

Upwelling System ◽

Benguela Upwelling ◽

The Impact ◽

Ocean Simulation

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Clay mineral-grain size-calcite cement relationships in the Upper Cretaceous Chalk, UK: a preliminary investigation

Clay Minerals ◽

10.1180/claymin.2014.049.2.09 ◽

2014 ◽

Vol 49 (2) ◽

pp. 299-325 ◽

Cited By ~ 7

Author(s):

C. V. Jeans ◽

N. J . Tosca ◽

X. F. Hu ◽

S. Boreham

Keyword(s):

Particle Size ◽

Particle Size Distribution ◽

Trace Element ◽

Size Distribution ◽

Clay Mineral ◽

Preliminary Investigation ◽

Clay Mineralogy ◽

Minor Amount ◽

Dioctahedral Smectite ◽

Calcite Cement

AbstractThe idea is tested that the evolution of the Chalk’s clay mineral assemblage during diagenesis can be deduced by examining the relationships between its clay mineralogy, particle size distribution pattern, and the timing and trace element chemistry of the calcite cement. The preliminary results from five different examples of cementation developed at different stages of diagenesis in chalks with smectite-dominated clay assemblages suggest that this is a promising line of investigation. Soft chalks with minor amount of anoxic series calcite cement poor in Mg, Fe and Mn are associated with neoformed trioctahedral smectite and/or dioctahedral nontronite and talc. Hard ground chalk with extensive anoxic series calcite cement enriched in Mg and relatively high Fe, Mn and Sr are associated with neoformed glauconite sensu lato, berthierine and dioctahedral smectite, possibly enriched in Fe. The chalk associated with large ammonites shows extensive suboxic series calcite cement enriched in Mg, Mn and Fe that show no obvious correlation with its clay mineralogy. Nodular chalks with patchy suboxic series calcite cement enriched in Fe are associated with neoformed dioctahedral smectite, possibly enriched in Al, and berthierine. Regionally hardened chalk with extensive suboxic calcite cement and relatively high trace element contents contain pressure dissolution seams enriched in kaolin and berthierine. Laser-based particle-size distribution patterns suggest that each type of lithification has a typical complex clay mineral population, indicating that subtleties in mineralogy are not being identified and that there could be some control on the size and shape of the clay crystals by the different types of cementation.

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Climate Evaluation of a High-Resolution Regional Model over the Canary Current Upwelling System

Lecture Notes in Computer Science - Computational Science – ICCS 2019 ◽

10.1007/978-3-030-22747-0_19 ◽

2019 ◽

pp. 240-252

Author(s):

Ruben Vazquez ◽

Ivan Parras-Berrocal ◽

William Cabos ◽

Dmitry V. Sein ◽

Rafael Mañanes ◽

...

Keyword(s):

High Resolution ◽

Regional Model ◽

Upwelling System

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Interpretation of Extragalactic Jets

International Astronomical Union Colloquium ◽

10.1017/s0252921100086206 ◽

1986 ◽

Vol 89 ◽

pp. 425-437

Author(s):

Michael L. Norman

Keyword(s):

High Resolution ◽

Visual Inspection ◽

Physical Parameters ◽

Model Calculations ◽

Radio Jets ◽

Extragalactic Jets ◽

Self Consistent ◽

Interferometric Observation ◽

The Subject

The subject of this paper is the interpretation of extragalactic radio jets. In this paper I will focus on what we have learned about the nature of extragalactic jets on the basis of model calculations. By model I mean any set of calculations, whether analytic, semi-analytic or numerical, which, when carried through from their respective assumptions to their internally self-consistent conclusions, help place constraints on the physical parameters and processes in the jets and their associated radio lobes. In this field, a visual inspection of a modern high-resolution radio interferometric observation (see review by PERLEY in these proceedings) often leads to statements like “that looks just like such and such in Landau and Lifschitz; I betcha that’s what’s going on!” This I call a speculation, or, at best, a hypothesis. I am addressing here the step beyond hypothesis, namely modeling, which is necessary to confront not only the object in question, but more importantly, the hypothesis itself. In the end, we will remember only the hypotheses.

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UAV and LiDAR Data in the Service of Bank Gully Erosion Measurement in Rambla de Algeciras Lakeshore

Water ◽

10.3390/w12102748 ◽

2020 ◽

Vol 12 (10) ◽

pp. 2748

Author(s):

Radouane Hout ◽

Véronique Maleval ◽

Gil Mahe ◽

Eric Rouvellac ◽

Rémi Crouzevialle ◽

...

Keyword(s):

High Resolution ◽

Point Clouds ◽

Sediment Budget ◽

Lidar Data ◽

Different Types ◽

The Subject ◽

Geomorphological Changes ◽

Uncertainty Models ◽

Geological Formations ◽

Different Sources

The Rambla de Algeciras lake in Murcia is a reservoir for drinking water and contributes to the reduction of flooding. With a semi-arid climate and a very friable nature of the geological formations at the lakeshore level, the emergence and development of bank gullies is favored and poses a problem of silting of the dam. A study was conducted on these lakeshores to estimate the sediment input from the bank gullies. In 2018, three gullies of different types were the subject of three UAV photography missions to model in high resolution their low topographic change, using the SfM-MVS photogrammetry method. The combination of two configurations of nadir and oblique photography allowed us to obtain a complete high-resolution modeling of complex bank gullies with overhangs, as it was the case in site 3. To study annual lakeshore variability and sediment dynamics we used LiDAR data from the PNOA project taken in 2009 and 2016. For a better error analysis of UAV photogrammetry data we compared spatially variable and uniform uncertainty models, while taking into account the different sources of error. For LiDAR data, on the other hand, we used a spatially uniform error model. Depending on the geomorphology of the gullies and the configuration of the data capture, we chose the most appropriate method to detect geomorphological changes on the surfaces of the bank gullies. At site 3 the gully topography is complex, so we performed a 3D distance calculation between point clouds using the M3C2 algorithm to estimate the sediment budget. On sites 1 and 2 we used the DoD technique to estimate the sediment budget as it was the case for the LiDAR data. The results of the LiDAR and UAV data reveal significant lakeshore erosion activity by bank gullies since the annual inflow from the banks is estimated at 39 T/ha/year.

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Residence and fractionation of rare earth elements during kaolinization of alkaline peraluminous granites in NW Spain

Clay Minerals ◽

10.1180/claymin.2007.042.3.07 ◽

2007 ◽

Vol 42 (3) ◽

pp. 341-352 ◽

Cited By ~ 42

Author(s):

E. Galán ◽

J. C. Fernández-Caliani ◽

A. Miras ◽

P. Aparicio ◽

M. G. Márquez

Keyword(s):

Rare Earth ◽

Rare Earth Elements ◽

Dominant Role ◽

Clay Mineralogy ◽

Distribution Patterns ◽

Weathering Profile ◽

Nw Spain ◽

Peraluminous Granites ◽

Mineralogical Study ◽

Different Grain Size

AbstractA geochemical and mineralogical study has allowed us to address the factors controlling distribution pattern, residence and behaviour of rare earth elements (REE) during kaolinization of Variscan granitoids in NW Spain. Mineral composition of the deeply weathered samples is dominated by kaolinite, with minor amounts of quartz, muscovite-illite, alkaline feldspar and traces of resistant minerals (rutile, ilmenite, zircon and monazite). Variable amounts of Si, Na, Ca, K, Rb, Cs, Ba, U and P were lost from the weathering profile, as a result of feldspars, mica and apatite breakdown, whereas Al, Fe, Ti, Zr, Th, Hf and REE were concentrated in the residual kaolin. Chondrite-normalized REE patterns of the kaolins show an overall enrichment of light REE (LaN/SmN = 1.22–2.53), heavy REE depletion (GdN/YbN = 2.42–15.10) and a strong negative Eu anomaly (Eu/Eu* = 0.11–0.25), probably inherited from the parent granite. Nevertheless, the normalization to the parent granite reveals some REE fractionation and increasing positive Eu anomalies with advancing weathering, in response to the breakdown of feldspars. Different grain-size fractions show similar REE distribution patterns, but differ in concentration levels. Although the fine fractions are the most important REE reservoir, there is no positive correlation with clay mineralogy. The correlative behaviour among P2O5, Th and REE in the <2 mm fraction suggests that monazite plays a dominant role controlling the REE budget in the weathering profile.

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