scholarly journals Detailed clay mineralogy of the Triassic-Jurassic boundary section at Kendlbachgraben (Northern Calcareous Alps, Austria)

Clay Minerals ◽  
2012 ◽  
Vol 47 (2) ◽  
pp. 177-189 ◽  
Author(s):  
N. Zajzon ◽  
F. Kristály ◽  
J. Pálfy ◽  
T. Németh
Keyword(s):  
Large Scale ◽  
Volcanic Ash ◽  
Clay Mineralogy ◽  
Volcanic Glass ◽  
Mass Extinctions ◽  
Humid Climate ◽  
Central Atlantic Magmatic Province ◽  
Central Atlantic ◽  
Moderate Climate ◽  
Shape And Size

AbstractThe Triassic-Jurassic boundary (TJB) is marked by one of the five largest Phanerozoic mass extinctions. To constrain existing models for TJB events, we obtained a stratigraphically highly resolved dataset from a marine section at Kendlbachgraben, Austria.The topmost Triassic Kössen Formation contains low to medium-charged smectite and vermiculite as alteration products of mafic-ultramafic minerals. The clay minerals in the boundary mudstone are kaolinite ⩾ illite + muscovite ⨠ smectite > chlorite. Predominant kaolinite suggests humid climate and abundant terrigenous input. In the lowermost Jurassic, the clay mineral pattern changes to illite + muscovite ⨠ kaolinite ⨠ smectite, which reflects change to less humid and more moderate climate.The topmost Kössen Formation also contains clay spherules. Their composition, shape and size indicate that they are alteration products of airborne volcanic glass droplets solidified in the air, settled in the sea and altered rapidly with negligible transport in terrestrial or marine environments. Our data are consistent with sudden climatic change at the TJB, as a result of large-scale volcanic activity of the Central Atlantic Magmatic Province which produced distal airfall volcanic ash.

Deep CO2 from the Central Atlantic Magmatic Province during the end-Triassic mass extinction

2021 ◽  
Author(s):  
Manfredo Capriolo ◽  
Andrea Marzoli ◽  
László E Aradi ◽  
Sara Callegaro ◽  
Jacopo Dal Corso ◽  
...  
Keyword(s):  
Mass Extinction ◽  
Melt Inclusions ◽  
Environmental Changes ◽  
Analytical Techniques ◽  
Global Scale ◽  
Large Igneous Province ◽  
Mass Extinctions ◽  
Basaltic Rocks ◽  
Central Atlantic Magmatic Province ◽  
Central Atlantic

<p>Throughout Earth’s history, the coincidence in time between Large Igneous Province eruptions and mass extinctions points out a potential causality, where volcanic degassing may drive the global-scale climatic and environmental changes leading to biotic crises. The volcanic activity of the Central Atlantic Magmatic Province (CAMP, ca. 201 Ma), one of Earth’s most voluminous Large Igneous Provinces, is synchronous with the end-Triassic mass extinction event, among the most severe extinctions during the Phanerozoic. Combining different in situ analytical techniques (optical microscopy, confocal Raman microspectroscopy, EMP, SEM-EDS, and NanoSIMS analyses), bubble-bearing melt inclusions within basaltic rocks revealed the abundance of CO<sub>2</sub> (up to 1.0 wt.%) in CAMP magmas [1]. Gaseous CO<sub>2 </sub>and solid elemental C, alternatively preserved by gas exsolution bubbles within melt inclusions mainly hosted in clinopyroxene crystal clots, represent direct evidence for large amounts of volcanic CO<sub>2</sub> (up to 10<sup>5</sup> Gt) emitted into Earth’s surface during the entire CAMP activity [1]. The entrapment conditions of these melt inclusions within clinopyroxene aggregates constrain the degassed CO<sub>2</sub> to a mantle and/or lower-middle crustal origin, indicating a deep source of carbon which may favour rapid and intense CAMP eruption pulses. Each magmatic pulse may have injected CO<sub>2</sub> into the end-Triassic atmosphere in amounts similar to those projected for the anthropogenic emissions during the 21<sup>st</sup> century [1]. Therefore, volcanic CO<sub>2</sub> degassed during CAMP eruptions likely contributed to end-Triassic global warming and ocean acidification with catastrophic consequences for the biosphere.</p><p> </p><p>[1] Capriolo et al. (2020), Nat. Commun. <strong>11</strong>, 1670.</p>

scholarly journals Massive methane fluxing from magma–sediment interaction in the end-Triassic Central Atlantic Magmatic Province

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Manfredo Capriolo ◽  
Andrea Marzoli ◽  
László E. Aradi ◽  
Michael R. Ackerson ◽  
Omar Bartoli ◽  
...  
Keyword(s):  
Mass Extinction ◽  
Environmental Changes ◽  
Global Climate ◽  
Large Igneous Province ◽  
Mass Extinctions ◽  
Quartz Crystals ◽  
Global Climate Changes ◽  
Central Atlantic Magmatic Province ◽  
Basaltic Magmas ◽  
Central Atlantic

AbstractExceptional magmatic events coincided with the largest mass extinctions throughout Earth’s history. Extensive degassing from organic-rich sediments intruded by magmas is a possible driver of the catastrophic environmental changes, which triggered the biotic crises. One of Earth’s largest magmatic events is represented by the Central Atlantic Magmatic Province, which was synchronous with the end-Triassic mass extinction. Here, we show direct evidence for the presence in basaltic magmas of methane, generated or remobilized from the host sedimentary sequence during the emplacement of this Large Igneous Province. Abundant methane-rich fluid inclusions were entrapped within quartz at the end of magmatic crystallization in voluminous (about 1.0 × 106 km3) intrusions in Brazilian Amazonia, indicating a massive (about 7.2 × 103 Gt) fluxing of methane. These micrometre-sized imperfections in quartz crystals attest an extensive release of methane from magma–sediment interaction, which likely contributed to the global climate changes responsible for the end-Triassic mass extinction.

Morphology, internal architecture and emplacement mechanisms of lava flows from the Central Atlantic Magmatic Province (CAMP) of Argana Basin (Morocco)

2011 ◽  
Vol 357 (1) ◽  
pp. 167-193 ◽  
Author(s):  
Hind El Hachimi ◽  
Nasrrddine Youbi ◽  
José Madeira ◽  
Mohamed Khalil Bensalah ◽  
Línia Martins ◽  
...  
Keyword(s):  
Lava Flows ◽  
Central Atlantic Magmatic Province ◽  
Central Atlantic ◽  
Internal Architecture

scholarly journals Динаміка розмірів сільськогосподарських полів як функція їх розмірів та форми

2007 ◽  
Vol 7 (3) ◽  
pp. 14-31
Author(s):  
O.V. Zhukov ◽  
V.O. Sirovatko ◽  
N.O. Ponomarenko
Keyword(s):  
Regression Analysis ◽  
Large Scale ◽  
Remote Sensing Data ◽  
Field Size ◽  
Agricultural Fields ◽  
Distribution Law ◽  
Administrative Area ◽  
Log Normal ◽  
Shape Characteristics ◽  
Shape And Size

<p>We estimated the size and shape characteristics of agricultural fields within the administrative area and identified patterns of the margin trends from 1950-1960 till the present time. Here we considered large-scale soil maps for the area of Vasilkovsky district of the Dnepropetrovsk region, which were drawn up in 1950-1960. To assess the landscape metric we used FRAGSTATS program which allow to make conformity assessment of the observed distributions of field sizes regards the normal, exponential, log-normal, gamma, Weibull, and Pareto distributions. We also used Box-Cox transformation to convert the experimental data into the normal distribution law for the further application of the transformed data in regression analysis. We estimated that the area of agricultural fields ranged from 1.20 to 269.00 hectares during the period of large-scale mapping in 1950-1960. The variation limits of the field sizes based on the results of remote sensing data and in our time they are 2,.5-266.57 hectares. Area of the fields in different periods strongly correlate and are statistically significant (<em>r</em> = 0.98, <em>p</em> = 0.00). Field sizes currently associated with the field sizes in the 50-60 years of linear regression. Shape parameters and field sizes significantly correlated, therefore, to establish the main trends of varying shape and size of fields, as well as for non-multicollinearity variables for regression analysis, we performed a multivariate factor analysis. An important aspect of the structuring of the agri-landscape is the location of settlements and, therefore, the fields distance from them. In results obtained indicate that the processes increase and decrease the size of fields in agricultural production are determined by various factors. Aspects of the shape and size of the fields associated with the dynamics of the processes that lead to variations in field areas. Fields that have shown a tendency to change their size, have different characteristics of forms and size from the stable fields. Typically, variable field size is smaller and more complex shapes.</p>

Sign in / Sign up

Export Citation Format

Share Document