Pressure—temperature—time ( P — T — t ) histories of erogenic belts

1987 ◽  
Vol 321 (1557) ◽  
pp. 27-45 ◽  
Keyword(s):  
Thermal Relaxation ◽  
Granite Gneiss ◽  
Crustal Thickening ◽  
Crustal Extension ◽  
Gneiss Domes ◽  
Short Time Span ◽  
Differential Uplift ◽  
Metamorphic Terranes ◽  
Short Time ◽  
Temperature Time

Thermal modelling shows that a cycle of crustal thickening and erosion reproduces many of the characteristics of medium-pressure metamorphic terranes. In contrast, the structural and metamorphic features of high-pressure terranes suggest rapid exhumation, possibly tectonically as fault-bounded blocks. Low-pressure metamorphism requires an augmented heat supply. Such terranes are characterized by granite—gneiss domes, and evidence of crustal extension, and hence may be the result of the mechanically likely orogenic sequence of early thickening followed by extension. Whether earlier isograd sequences are extended, condensed, or reset depends upon the relative rates of deformation and thermal relaxation, and when the deformation occurs relative to the thermal peak of metamorphism. Detailed determinations of relations between deformation events and metamorphism is made difficult by the contrast between continuous metamorphic evolution and short time-span deformation events. Combined microstructural and geochronological studies, together with a consideration of the distribution of isograds will give most information on complex, polymetamorphic histories, and allow distinction between regional and local features, especially those due to differential uplift.

scholarly journals Use of thermal modeling to assess the tectono-metamorphic history of the Lugo and Sanabria gneiss domes, Northwest Iberia

2009 ◽  
Vol 180 (3) ◽  
pp. 179-197 ◽  
Author(s):  
James E. Alcock ◽  
José R. Martínez Catalán ◽  
Ricardo Arenas ◽  
Alejandro Díez Montes
Keyword(s):  
Thermal Relaxation ◽  
Thermal Response ◽  
Crustal Thickening ◽  
Gneiss Domes ◽  
Metamorphic History ◽  
Thrust Sheets ◽  
History Of ◽  
Granite Magmatism ◽  
Geochronological Evidence ◽  
Northwest Iberia

Abstract The Lugo and Sanabria domes in Northwest Iberia have well constrained metamorphic and structural histories. Both occur in the Iberian autochthon and resulted from late-Variscan extensional collapse following crustal thickening related to the Variscan collision. The two domes developed beneath large thrust sheets, are cored by sillimanite-orthoclase anatectic gneiss, preserve evidence of a steep thermal gradient (≈ 1 °C MPa−1), and exhibit a distinct decrease in metamorphic grade to the east in the direction of nappe movement. Geochronological evidence indicates that the lower crust melted within ≈ 30 Ma of initial crustal thickening and that dome formation occurred within 50 Ma. The histories of the two domes are considered as the basis for one-dimensional finite-difference models of thermal response to changes in crustal thickness. Results from thermal models suggest that thickening was limited to the crust, provide a numeric explanation for timing and nature of granite magmatism, and indicate that high-temperature metamorphism and crustal anatexis may result directly from thermal relaxation, eliminating the need for significant mantle thermal contribution. Also, the models show that small differences in thickness of large, wedge-shaped thrust sheets can explain distinct P-T paths experienced by different limbs of the domes.

Gneiss Dome Formation in the Himalaya and southern Tibet

2019 ◽  
Vol 483 (1) ◽  
pp. 401-422 ◽  
Author(s):  
Micah J. Jessup ◽  
Jackie M. Langille ◽  
Timothy F. Diedesch ◽  
John M. Cottle
Keyword(s):  
Tibetan Plateau ◽  
Late Miocene ◽  
Shear Zones ◽  
Crustal Thickening ◽  
Southern Tibet ◽  
Gneiss Domes ◽  
Time Deformation ◽  
Temperature Time ◽  
The Himalaya ◽  
Parallel Extension

AbstractGneiss domes in the Himalaya and southern Tibet record processes of crustal thickening, metamorphism, melting, deformation and exhumation during the convergence between the Indian and Eurasian plates. We review two types of gneiss domes: North Himalayan gneiss domes (NHGD) and later domes formed by orogen-parallel extension. Located in the southern Tibetan Plateau, the NHGD are cored by granite and gneiss, and mantled by the Tethyan sedimentary sequence. The footwall of these were extruded southwards from beneath the Tibetan Plateau and subsequently warped into a domal shape. The second class of domes were formed during displacement on normal-sense shear zones and detachments that accommodated orogen-parallel extension during the Late Miocene. In some cases, formation of these domes involved an early stage of southwards-directed extrusion prior to doming. We review evidence for orogen-parallel extension to provide context for the formation of these gneiss domes. Compilations of pressure–temperature–time–deformation data and temperature–time paths indicate differences between dome types, and we accordingly propose new terminology. Type 1 domes are characterized by doming as an artefact of post-high-temperature exhumation processes in the Middle Miocene. Type 2 domes formed in response to exhumation during orogen-parallel extension in the Late Miocene that potentially post-dates south-directed extrusion.

scholarly journals ‘Scrupulous and Timid Conformism’: Ireland and the Reception of the Liturgical Changes of Vatican II

Religions ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 545
Author(s):  
Gary Carville
Keyword(s):  
Vatican Ii ◽  
Time Span ◽  
Second Vatican Council ◽  
The People ◽  
Vatican Council ◽  
Short Time Span ◽  
Irish Catholics ◽  
Catholic Tradition ◽  
Short Time ◽  
The Church

The Second Vatican Council and, in particular, its Constitution on the Sacred Liturgy, changed much in the daily life of the Church. In Ireland, a country steeped in the Catholic tradition but largely peripheral to the theological debates that shaped Vatican II, the changes to liturgy and devotional practice were implemented dutifully over a relatively short time span and without significant upset. But did the hierarchical manner of their reception, like that of the Council itself, mean that Irish Catholics did not receive the changes in a way that deepened their spirituality? And was the popular religious memory of the people lost through a neglect of liturgical piety and its place in the interior life, alongside what the Council sought to achieve? In this essay, Dr Gary Carville will examine the background to the liturgical changes at Vatican II, the contribution to their formulation and implementation by leaders of the Church in Ireland, the experiences of Irish Catholic communities in the reception process, and the ongoing need for a liturgical formation that brings theology, memory, and practice into greater dialogue.

scholarly journals A 20-Year Follow-Up Study of Objectively Measured Physical Activity

2021 ◽  
Vol 18 (6) ◽  
pp. 3076
Author(s):  
Anders Raustorp ◽  
Andreas Fröberg
Keyword(s):  
Physical Activity ◽  
Early Adolescence ◽  
Total Sample ◽  
Short Time Span ◽  
Steps Per Day ◽  
Objectively Measured ◽  
Short Time ◽  
Objectively Measured Physical Activity

Background: The objectives of this study were to explore the effect of time, long-term tracking, and the proportion of objectively measured physical activity (PA) from early adolescence to the mid-thirties. Methods: PA was measured as mean steps per day (SPD) with pedometers during 2000 (T1), 2003 (T2), 2005 (T3), 2010 (T4), 2016 (T5) and 2020 (T6). Data from 64 participants (n = 32 males) were analysed from their early adolescence (T1) to their mid-thirties (T6). Results: SPD decreased in the total sample and among males and females (all, p < 0.001). Males took more mean SPD than females during T1 (p = 0.002), whereas females took more mean SPD during T2 (p = 0.009) and T6 (p = 0.008). Males’ mean SPD tracked between T1 and T2 (p = 0.021), T2 and T3 (p = 0.030), T3 and T4 (p = 0.015) and T4 and T5 (p = 0.003). Females’ mean SPD tracked between T3 and T4 (p = 0.024) and T5 and T6 (p < 0.001). In the total sample, more mean SPD were found on weekdays compared to weekend days at T3 (p = 0.017) and T5 (p < 0.001). Conclusions: SPD decreased between T1 and T6. Mean SPD tracked low-to-moderate in the short time span. From late adolescence to the mid-thirties, more mean SPD was observed during weekdays compared to weekend days.

scholarly journals Chitinozoans and the age of the Soom Shale, an Ordovician black shale Lagerstätte, South Africa

2009 ◽  
Vol 28 (1) ◽  
pp. 53-66 ◽  
Author(s):  
Thijs R. A. Vandenbroucke ◽  
Sarah E. Gabbott ◽  
Florentin Paris ◽  
Richard J. Aldridge ◽  
Johannes N. Theron
Keyword(s):  
South Africa ◽  
New Species ◽  
Black Shale ◽  
Time Span ◽  
Northern Africa ◽  
Short Time Span ◽  
Short Time ◽  
A New Species

Abstract. Isolated chitinozoans from the Soom Shale Member of the Cedarberg Formation, SW South Africa are described and provide a date of the latest Hirnantian–earliest Rhuddanian. The recovered chitinozoans are typical of the latest Ordovician Spinachitina oulebsiri Biozone, although an earliest Silurian age is possible. They indicate a very short time span (less than 1 Ma) across the Ordovician–Silurian boundary. This is currently the highest biostratigraphical resolution attainable for the Soom Shale Lagerstätte. Correlation of the Soom Shale chitinozoans with identical assemblages in post-glacial, transgressive deposits of Northern Africa is possible; both faunas occur in shales that overlie glacial diamictites of the Hirnantian glaciation. A new species, Spinachitina verniersi n. sp. is described.

scholarly journals Rapid tranquillisation: practice in Zambia, before and after training

2013 ◽  
Vol 10 (4) ◽  
pp. 95-97
Author(s):  
Mahesh Jayaram ◽  
Ranga Rattehalli ◽  
Lindsay Moran ◽  
John Mwanza ◽  
Paul Banda ◽  
...  
Keyword(s):  
Evidence Base ◽  
Sub Saharan Africa ◽  
Collaborative Partnerships ◽  
Inappropriate Use ◽  
Short Time Span ◽  
Safety Awareness ◽  
Before And After ◽  
Sub Saharan ◽  
Therapeutic Doses ◽  
Short Time

The evidence base for rapid tranquillisation is small in higher-income countries but is even smaller in sub-Saharan Africa. We initiated the first ever survey on the use of rapid tranquillisation in Zambia in 2009; a further survey was then done in 2010, after a programme of teaching and training. It demonstrated an overall improvement in clinical practice, safety, awareness and use of medications within therapeutic doses. It also led to a reduction in inappropriate use of medications. These improvements in practice occurred within a short time span and with minimal effort. Further international collaborative partnerships are required to build stronger mental health infrastructure in Zambia.

The Physical Environment of Lakes

2003 ◽  
Author(s):  
Andrew S. Cohen
Keyword(s):  
Water Column ◽  
Hydrological Cycle ◽  
Biological Information ◽  
Lake Basin ◽  
Physical Processes ◽  
Sediment Types ◽  
Short Time Span ◽  
Heat Penetration ◽  
Short Time ◽  
Inputs And Outputs

Before discussing paleolimnological archives, we need to consider those aspects of limnology that regulate how information is produced, transmitted, and filtered through the water column. Although many limnological processes leave behind sedimentary clues of their existence or intensity and are thus amenable to paleolimnological analysis, others leave little or no detectable trace. Our consideration of limnology here emphasizes the former. Throughout the next three chapters we will examine the properties of lakes, the implications of these properties for paleolimnology, and the types of physical, chemical, and biological information that can be transcribed into sedimentary archives. Physical processes in lakes are of interest because they act as intermediary hydroclimate filters between external forcing events of interest, like climate, and the paleolimnological record. For example, understanding the hydrology of a lake is important because water inputs and outputs, which are often controlled by climate, determine lake levels, which in turn are recorded by ancient shoreline elevations, or indirectly by salinity indicators. Light and heat penetration regulate the distribution of organisms and the mixing of the water column, recorded by the distribution of various fossils, sediment types, and geochemical characteristics of sediments. Also, current and wave activity affect the transport of sedimentary particles and therefore the distribution of sediment types around a lake basin. Understanding these physical processes therefore provides us with a means of linking sedimentological, geochemical, and paleobiological records of lake deposits to the external environment. Water enters and exits lakes through a variety of paths that comprise part of the earth’s hydrological cycle. The lake components of this cycle include a series of inputs and outputs of water, which in combination with the morphometry of the lake basin, collectively determine the lake’s level. Inputs include precipitation, surface runoff from rivers, and groundwater discharge into the lake. Outflows include surface outflow, evaporation, evapotranspiration losses from emergent aquatic plants, groundwater recharge, and hydration reactions with underlying sediments. If water inputs and outputs for a lake are equal over a short time span, the lake surface elevation will remain constant. This is approximately the case in most lakes that are surficially open basins.

The Revised Role Checklist: Improved Utility, Feasibility, and Reliability

2018 ◽  
Vol 39 (1) ◽  
pp. 56-63
Author(s):  
Patricia J. Scott ◽  
Kelsey G. McKinney ◽  
Jeff M. Perron ◽  
Emily G. Ruff ◽  
Jessica L. Smiley
Keyword(s):  
Occupational Therapists ◽  
Occupational Performance ◽  
Human Occupation ◽  
Retest Reliability ◽  
Short Time Span ◽  
Model Of Human Occupation ◽  
Feasibility Test ◽  
Test Retest Reliability ◽  
Short Time ◽  
Role Engagement

The Role Checklist is used by occupational therapists across the globe. Developed in 1981 and consistent with the Model of Human Occupation (MOHO), until recently, the Role Checklist was not updated. This is of concern as the Role Checklist originally was established to measure role performance. In 2008, Kielhofner, in the fourth edition of A Model of Human Occupation, differentiated occupational performance in 10 roles which clearly fall into occupational participation in the Role Checklist Version 3. The objective of the study was to describe changes and establish utility, feasibility, and reliability of the Role Checklist Version 3. The Role Checklist Version 3 was administered electronically to N = 114 occupational therapists and students. A short time span was used due to sensitivity to history bias. Test–retest reliability using Cohen’s Kappa and Cronbach’s alpha mirrored analysis done on the original version. Qualitatively, nine themes emerged regarding utility and feasibility. Test–retest reliability is acceptable to excellent for present role incumbency (κ = 0.74-1.00), desired future role engagement (κ = 0.44-1.00), and satisfaction with performance (α = 0.77-0.98). Participants (91%) found it useful for treatment planning and 75% would recommend Version 3 over the original Role Checklist. Data support the Role Checklist Version 3 as a reliable, electronic instrument feasible for occupational therapists to measure participation.

scholarly journals The First Find of Cr2O3 Eskolaite Associated with Marble-Hosted Ruby in the Southern Urals and the Problem of Al and Cr Sources

Minerals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 101
Author(s):  
Aleksander Kissin ◽  
Irina Gottman ◽  
Sergei Sustavov ◽  
Valery Murzin ◽  
Daria Kiseleva
Keyword(s):  
Granite Gneiss ◽  
Southern Urals ◽  
X Ray Diffraction ◽  
The Southern Urals ◽  
Near Surface ◽  
X Ray ◽  
Gneiss Domes ◽  
Electron Probe Microanalyzer ◽  
Formation Zone ◽  
First Time

The results of the study of eskolaite associated with marble-hosted ruby found for the first time in the Kuchinskoe occurrence (Southern Urals) are presented. Here, eskolaite was located on the surface and near-surface regions of ruby crystals. Eskolaite diagnostics was confirmed by powder X-ray diffraction (URS-55). The morphology and chemical composition of eskolaite and associated ruby was studied using a JSM-6390LV scanning electron microscope and a Cameca SX 100 electron probe microanalyzer. The eskolaite crystals were hexagonal and tabular, up to 0.2 mm in size. Ruby mineralization was formed during prograde and retrograde dynamothermal metamorphism. The eskolaite associated with the prograde stage ruby contained Al2O3 (9.1–23.62 wt %), TiO2 (0.52–9.66 wt %), V2O3 (0.53–1.54 wt %), FeO (0.03–0.1 wt %), MgO (0.05–0.24 wt %), and SiO2 (0.1–0.21 wt %). The eskolaite associated with the retrograde stage ruby was distinguished by a sharp depletion in Ti and contained Al2O3 (12.25–21.2 wt %), TiO2 (0.01–0.07 wt %), V2O3 (0.32–1.62 wt %), FeO (0.01–0.08 wt %), MgO (0.0–0.48 wt %), and SiO2 (0.01–0.1 wt %). The associated rubies contained almost equal amounts of Cr2O3 (2.36–2.69 wt %) and were almost free from admixtures. The identification of the eskolaite associated with the marble-hosted rubies from the Kuchinskoe occurrence is a new argument in favor of introduction of Al and Cr into the mineral formation zone. The mineralization was localized in the metamorphic frame of the granite gneiss domes and was formed synchronously with them.

scholarly journals Model-Based Analysis and Engineering of Automotive Architectures with EAST-ADL

2015 ◽  
Vol 3 (2) ◽  
pp. 25-70 ◽  
Author(s):  
Ramin Tavakoli Kolagari ◽  
DeJiu Chen ◽  
Agnes Lanusse ◽  
Renato Librino ◽  
Henrik Lönn ◽  
...  
Keyword(s):  
Description Language ◽  
System Description ◽  
Architecture Description Language ◽  
Model Based ◽  
Technology Products ◽  
Short Time Span ◽  
Development Processes ◽  
Architecture Description ◽  
Short Time ◽  
Model Based Analysis

Modern cars have turned into complex high-technology products, subject to strict safety and timing requirements, in a short time span. This evolution has translated into development processes that are not as efficient, flexible and agile as they could or should be. This paper presents the main aspects and capabilities of a rich model-based design framework, founded on EAST-ADL. EAST-ADL is an architecture description language specific to the automotive domain and complemented by a methodology compliant with the functional safety standard for the automotive domain ISO26262. The language and the methodology are used to develop an information model in the sense of a conceptual model, providing the engineer the basis for specifying the various aspects of the system. Inconsistencies, redundancies, and partly even missing system description aspects can be found automaticlally by advanced analyses and optimization capabilities to effectively improve development processes of modern cars.

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