The magmatic evolution of the late Miocene laccolith–pluton–dyke granitic complex of Elba Island, Italy

2002 ◽  
Vol 139 (3) ◽  
pp. 257-279 ◽  
Author(s):  
A. DINI ◽  
F. INNOCENTI ◽  
S. ROCCHI ◽  
S. TONARINI ◽  
D. S. WESTERMAN

Since late Miocene time, post-collisional extension of the internal parts of the Apennine orogenic belt has led to the opening of the Tyrrhenian basin. Extensive, mainly acidic peraluminous magmatism affected the Tuscan Archipelago and the Italian mainland during this time, building up the Tuscan Magmatic Province as the fold belt was progressively thinned, heated and intruded by mafic magmas. An intrusive complex was progressively built on western Elba Island by emplacement, within a stack of nappes, of multiple, shallow-level porphyritic laccoliths, a major pluton, and a final dyke swarm, all within the span from about 8 to 6.8 Ma. New geochemical and Sr–Nd isotopic investigations constrain the compositions of materials involved in the genesis of the magmas of Elba Island compared to the whole Tuscan Magmatic Province. Several distinct magma sources, in both the crust and mantle, have been identified as contributing to the Elba magmatism as it evolved from crust-, to hybrid-, to mantle-dominated. However, a restricted number of components, geochemically similar to mafic K-andesites of the Island of Capraia and crustal melts like the Cotoncello dyke at Elba, are sufficient to account for the generation by melt hybridization of the most voluminous magmas (c. εNd(t) −8.5, 87Sr/86Sr 0.715). Unusual magmas were emplaced at the beginning and end of the igneous activity, without contributing to the generation of these hybrid magmas. These are represented by early peraluminous melts of a different crustal origin (εNd(t) between −9.5 and −10.0, 87Sr/86Sr variable between 0.7115 and 0.7146), and late mantle-derived magma strongly enriched in incompatible elements (εNd(t) = −7.0, 87Sr/86Sr = 0.7114) with geochemical–isotopic characteristics intermediate between contemporaneous Capraia K-andesites and later lamproites from the Tuscan Magmatic Province. Magmas not involved in the generation of the main hybrid products are not volumetrically significant, but their occurrence emphasizes the highly variable nature of crust and mantle sources that can be activated in a short time span during post-collisional magmatism.

Author(s):  
Lotte Melchior Larsen ◽  
David C. Rex ◽  
W. Stuart Watt ◽  
Philip G. Guise

NOTE: This article was published in a former series of GEUS Bulletin. Please use the original series name when citing this article, for example: Melchior Larsen, L., Rex, D. C., Watt, W. S., & Guise, P. G. (1999). 40Ar–39Ar dating of alkali basaltic dykes along the southwest coast of Greenland: Cretaceous and Tertiary igneous activity along the eastern margin of the Labrador Sea. Geology of Greenland Survey Bulletin, 184, 19-29. https://doi.org/10.34194/ggub.v184.5227 _______________ A 380 km long coast-parallel alkali basalt dyke swarm cutting the Precambrian basement in south-western Greenland has generally been regarded as one of the earliest manifestations of rifting during continental stretching prior to break-up in the Labrador Sea. Therefore, the age of this swarm has been used in models for the evolution of the Labrador Sea, although it has been uncertain due to earlier discrepant K–Ar dates. Two dykes from this swarm situated 200 km apart have now been dated by the 40Ar–39Ar step-heating method. Separated biotites yield plateau ages of 133.3 ± 0.7 Ma and 138.6 ± 0.7 Ma, respectively. One of the dykes has excess argon. Plagioclase separates confirm the biotite ages but yield less precise results. The age 133– 138 Ma is earliest Cretaceous, Berriasian to Valanginian, and the dyke swarm is near-coeval with the oldest igneous rocks (the Alexis Formation) on the Labrador shelf. A small swarm of alkali basalt dykes in the Sukkertoppen (Maniitsoq) region of southern West Greenland was also dated. Two separated kaersutites from one sample yield an average plateau age of 55.2 ± 1.2 Ma. This is the Paleocene–Eocene boundary. The swarm represents the only known rocks of that age within several hundred kilometres and may be related to changes in the stress regime during reorganisation of plate movements at 55 Ma when break-up between Greenland and Europe took place.


Religions ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 545
Author(s):  
Gary Carville

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.


Author(s):  
Anders Raustorp ◽  
Andreas Fröberg

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.


2009 ◽  
Vol 28 (1) ◽  
pp. 53-66 ◽  
Author(s):  
Thijs R. A. Vandenbroucke ◽  
Sarah E. Gabbott ◽  
Florentin Paris ◽  
Richard J. Aldridge ◽  
Johannes N. Theron

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.


2013 ◽  
Vol 10 (4) ◽  
pp. 95-97
Author(s):  
Mahesh Jayaram ◽  
Ranga Rattehalli ◽  
Lindsay Moran ◽  
John Mwanza ◽  
Paul Banda ◽  
...  

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.


Author(s):  
Andrew S. Cohen

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.


2020 ◽  
Vol 105 (12) ◽  
pp. 1841-1856 ◽  
Author(s):  
Yonghua Cao ◽  
Christina Yan Wang ◽  
Bo Wei

Abstract Oxygen fugacities (fO2) of mantle-derived mafic magmas have important controls on the sulfur status and solubility of the magmas, which are key factors to the formation of magmatic Ni-Cu sulfide deposits, particularly those in convergent margin settings. To investigate the fO2 of mafic magmas related to Ni-Cu sulfide deposits in convergent margin settings, we obtained the magma fO2 of several Ni-Cu sulfide-bearing mafic-ultramafic intrusions in the Central Asian Orogenic Belt (CAOB), North China, based on the olivine-spinel oxygen barometer and the modeling of V partitioning between olivine and melt. We also calculated the mantle fO2 on the basis of V/Sc ratios of primary magmas of these intrusions. Ni-Cu sulfide-bearing mafic-ultramafic intrusions in the CAOB include arc-related Silurian-Carboniferous ones and post-collisional Permian-Triassic ones. Arc-related intrusions formed before the closure of the paleo-Asian ocean and include the Jinbulake, Heishan, Kuwei, and Erbutu intrusions. Post-collisional intrusions were emplaced in extensional settings after the closure of the paleo-Asian ocean and include the Kalatongke, Baixintan, Huangshandong, Huangshan, Poyi, Poshi, Tulaergen, and Hongqiling No. 7 intrusions. It is clear that the magma fO2 values of all these intrusions in both settings range mostly from FMQ+0.5 (FMQ means fayalite-magnetite-quartz oxygen buffer) to FMQ+3 and are generally elevated with the fractionation of magmas, much higher than that of MORBs (FMQ-1 to FMQ+0.5). However, the mantle fO2 values of these intrusions vary from ~FMQ to ~FMQ+1.0, just slightly higher than that of mid-ocean ridge basalts (MORBs) (≤FMQ). This slight difference is interpreted as the intrusions in the CAOB may have been derived from the metasomatized mantle wedges where only minor slab-derived, oxidized components were involved. Therefore, the high-magma fO2 values of most Ni-Cu sulfide-bearing mafic-ultramafic intrusions in the CAOB were attributed to the fractionation of magmas derived from the slightly oxidized metasomatized mantle. In addition, the intrusions that host economic Ni-Cu sulfide deposits in the CAOB usually have magma fO2 of &gt;FMQ+1.0 and sulfides with mantle-like δ34S values (–1.0 to +1.1‰), indicating that the oxidized mafic magmas may be able to dissolve enough mantle-derived sulfur to form economic Ni-Cu sulfide deposits. Oxidized mafic magmas derived from metasomatized mantle sources may be an important feature of major orogenic belts.


2018 ◽  
Vol 39 (1) ◽  
pp. 56-63
Author(s):  
Patricia J. Scott ◽  
Kelsey G. McKinney ◽  
Jeff M. Perron ◽  
Emily G. Ruff ◽  
Jessica L. Smiley

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.


Author(s):  
Ramin Tavakoli Kolagari ◽  
DeJiu Chen ◽  
Agnes Lanusse ◽  
Renato Librino ◽  
Henrik Lönn ◽  
...  

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.


2020 ◽  
Vol 35 (6) ◽  
pp. 1089-1098
Author(s):  
Erik Mooi ◽  
Vishal Kashyap ◽  
Marc van Aken

Purpose This paper aims to consider the impact of contractual and normative governance mechanisms on recommendation intent in a context of healthcare and professional lighting where repeat business from a customer is absent. The authors suggest both contractual and normative governance can create recommendation intent, but only when sufficient customer value is created. Design/methodology/approach The authors draw on a combination of survey and archival data from the supplier and customer in the medical equipment and advanced (business) lighting systems industries. The authors analyze the data using seemingly unrelated regression and mediation tests. Findings Contracts and relational norms can increase customer recommendation intent, but only when the supplier creates customer value. Practical implications The paper’s findings suggest that customers of business solutions are more likely to recommend their supplier when contracts are relatively detailed and when buyers and suppliers attempt to craft strong relational norms, despite service solutions being delivered during a relatively short time span. Originality/value The extant research on business solutions has focused on extended relationships between exchange partners with a high likelihood of repeated transactions. The authors demonstrate how to govern relationships in a solutions context where the likelihood of repeat business from the same customer is low using contractual and normative governance.


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