Timescales of plutonic-subvolcanic-volcanic connection in a Mio-Pliocene long-lived igneous system (Tuscany): zircon CA-ID-TIMS dating

2021 ◽  
Author(s):  
Gabriele Paoli ◽  
Andrea Dini ◽  
Maria Ovtcharova ◽  
Sergio Rocchi
Keyword(s):  
Full Range ◽  
Time Span ◽  
Crystallization Time ◽  
Geochronological Data ◽  
Peraluminous Granite ◽  
Granite Pluton ◽  
Icp Ms ◽  
Plumbing Systems ◽  
Deep Reservoir ◽  
Different Levels

<p>The genetic link between plutonic and volcanic realms is a key for understanding timescales of igneous plumbing systems, and precise geochronological records are pivotal in estimating the duration of processes at different levels in such plumbing systems. The Campiglia igneous complex, Tuscany, offers exposures of the full range of emplacement levels (plutonic, subvolcanic, volcanic) of mantle- and crust-derived magmas. Magma emplacement occurred astride the Miocene-Pliocene boundary. New high-precision U-Pb CA-ID-TIMS, zircon geochronological data, coupled with LA-HR-ICP-MS zircon dates for the whole Campiglia system define a short crystallization time span for zircon from the peraluminous granite pluton (~100 ka), intermediate for the shallow-level mafic porphyry (~450 ka), and longer for the rhyolite (~700 ka), at odd with what commonly expected. The oldest ages for the three units are the same, leading to hypothesize the occurrence of a bimodal deep reservoir remaining in melt-present conditions for some 700 ka. In this framework, early-crystallized zircons were cannibalized by younger melt batches that were sequentially extracted from the reservoir.</p>

User identification across online social networks in practice: Pitfalls and solutions

2016 ◽  
Vol 44 (3) ◽  
pp. 377-391 ◽  
Author(s):  
Azadeh Esfandyari ◽  
Matteo Zignani ◽  
Sabrina Gaito ◽  
Gian Paolo Rossi
Keyword(s):  
Social Networks ◽  
Online Social Networks ◽  
Full Range ◽  
Application Programming Interface ◽  
User Identification ◽  
Application Programming ◽  
Test Sets ◽  
Set Up ◽  
Different Levels ◽  
Programming Interface

To take advantage of the full range of services that online social networks (OSNs) offer, people commonly open several accounts on diverse OSNs where they leave lots of different types of profile information. The integration of these pieces of information from various sources can be achieved by identifying individuals across social networks. In this article, we address the problem of user identification by treating it as a classification task. Relying on common public attributes available through the official application programming interface (API) of social networks, we propose different methods for building negative instances that go beyond usual random selection so as to investigate the effectiveness of each method in training the classifier. Two test sets with different levels of discrimination are set up to evaluate the robustness of our different classifiers. The effectiveness of the approach is measured in real conditions by matching profiles gathered from Google+, Facebook and Twitter.

Shoulder examination: a systematic approach

2021 ◽  
pp. 1-15
Author(s):  
Akib M Khan ◽  
Angelos Assiotis ◽  
Mazin S Ibrahim ◽  
Andrew R Sankey
Keyword(s):  
Rotator Cuff ◽  
Systematic Approach ◽  
Healthcare Professionals ◽  
Full Range ◽  
Range Of Movement ◽  
Systematic Examination ◽  
Complex Joint ◽  
Different Levels ◽  
Shoulder Examination

The shoulder is a complex joint with static and dynamic stabilising structures working synchronously. These allow a full range of movement while preserving stability of the joint. Patients may present with pain, stiffness, weakness, deformity or instability. The authors suggest a systematic examination sequence to ensure that important pathology is not overlooked. Adopting this approach allows common pathologies, including tears of the rotator cuff, impingement and tendinopathy, to be easily identified. This shoulder examination sequence may be used by all healthcare professionals and can also act as a revision aid for those undergoing exams in this field, at different levels of training.

A geochronological framework for sedimentation and Mesoproterozoic tectono-magmatic activity in lower Belt–Purcell rocks exposed west of Kimberley, British Columbia

2015 ◽  
Vol 52 (7) ◽  
pp. 444-465 ◽  
Author(s):  
Christopher R.M. McFarlane
Keyword(s):  
British Columbia ◽  
Minor Component ◽  
Structural Level ◽  
Peraluminous Granite ◽  
Icp Ms ◽  
Ductile Shearing ◽  
History Of ◽  
Metamorphic Zone ◽  
A Minor ◽  
Plate Reconstruction

The Matthew Creek Metamorphic Zone (MCMZ) exposes what is inferred to be the lowest structural level of the lower Aldridge Formation in the Canadian portion of the Belt–Purcell Supergroup. Zircon, monazite, and titanite were dated using the U–Pb system by LA–ICP–MS. The detrital zircon populations of quartzite layers in these rocks define a provenance dominated by sources of Laurentian affinity with a minor component of non-North American ages between 1600 and 1490 Ma. Special attention was paid to monazite in sillimanite-grade metapelitic schists that was analyzed using in situ LA–ICP–MS techniques guided by BSE imaging and compositional mapping. Textural and geochronological evidence indicate that coupled dissolution–reprecipitation affected detrital monazite at 1413 ± 10 Ma. This was followed by prograde monazite growth at 1365 ± 10 Ma, synchronous with crystallization of the nearby Hellroaring Creek peraluminous granite at 1365 ± 5 Ma. Late-stage pegmatite emplacement and ductile shearing along the contact of the MCMZ and overlying rocks occurred at 1335 ± 5 Ma, interpreted as a period of post-collisional extension, core complex formation, exhumation, and decompression melting. The entire package was subsequently affected by a pervasive ∼1050 Ma hydrothermal overprint that partially reset U–Pb dates in monazite, zircon, and titanite contained in all lithologies examined. The lowermost Belt–Purcell stratigraphy in southeast British Columbia preserves a detailed record of sedimentary provenance and a long history of episodic collision and extension that must be reconciled with plate reconstruction models for the break-up of the Nuna supercontinent and assembly of Rodinia.

scholarly journals New U-Pb geochronological data on the age of volcanic-plutonic assemblage of Oloy belt, Alazey-Oloy fold system (West Chukotka)

2019 ◽  
Vol 487 (6) ◽  
pp. 653-658
Author(s):  
T. V. Kara ◽  
M. V. Luchitskaya ◽  
S. M. Katkov ◽  
E. A. Belousova
Keyword(s):  
Early Cretaceous ◽  
Late Jurassic ◽  
Volcanic Rocks ◽  
Volcanic Belt ◽  
Geochronological Data ◽  
Fold System ◽  
Hypabyssal Intrusions ◽  
Icp Ms ◽  
Age Limits ◽  
Felsic Volcanic

New U-Pb (SIMS and LA-ICP-MS) geochronological data for rocks of Egdygkych complex of hypabyssal intrusions, Nichan and Vukney plutons, and felsic volcanic rocks and tuffs from host strata of Oloy volcanic belt of Alasey-Oloy fold system are obtained. Concordant ages of Egdygkych complex rocks correspond to Early Cretaceous (Berriasian-Valanginian), those for host strata, to the end of Late Jurassic (Tithonian) - beginning of Early Cretaceous (Berriasian). New U-Pb geochronological data allow confidently to distinguish uniform volcanic-plutonic assemblage of Late Jurassic (Tithonian) - Early Cretaceous (Berriasian-Valanginian) age of Oloy volcanic belt. Obtained data more definitely determine age limits of Au-Mo-Cu mineralization, associated with contacts between rocks of Egdydkych complex and host volcanic-sedimentary rocks or contacts of separated intrusive phases.

scholarly journals Indicators of Mineral Metabolism Depending on the Body Mass Index

2021 ◽  
Author(s):  
Olga Marshinskaia ◽  
Tatiana Kazakova ◽  
Svetlana Notova ◽  
Marat Gedulianov
Keyword(s):  
Body Mass Index ◽  
Body Mass ◽  
Adolescent Girls ◽  
Mineral Metabolism ◽  
The Body ◽  
Orenburg Region ◽  
Daily Diet ◽  
Icp Ms ◽  
Elemental Status ◽  
Different Levels

n this study, the elemental status of the hair of adolescent girls in the Orenburg region (n=120) with different levels of body mass index was studied and their average daily diet was evaluated. A nutrition assessment program was used to study the diet. Estimation of the element status was carried out through the study of the chemical composition of the hair by ICP-AES and ICP-MS. It was found that there was a general imbalance of elements in the diet of all of the studied groups, and students with obesity had lower consumption levels of all elements, except Mg and Se. Similarly, obese students had lower levels of all elements in their hair except Se, P, and Zn. Thus, changes in the level of body mass index, as well as geochemical features of the territory of the Orenburg region, affect the content of most macro- and microelements. Keywords: metabolic syndrome, trace elements, body mass index

scholarly journals LA-ICP-MS U-Pb geochronology on monazite: Geologic “date” and geologic event duration. Comment on the paper by H.-J. Massonne, European Journal of Mineralogy, DOI:10.1127/ejm/2016/0028-2575

2020 ◽  
Vol 81 (2) ◽  
pp. 89-93
Author(s):  
Ivan Zagorchev
Keyword(s):  
Time Span ◽  
Single Sample ◽  
Metamorphic Event ◽  
Event Duration ◽  
Icp Ms ◽  
Geological Information

We comment here a paper that is entirely built on a single sample of metapelites belonging to the Lukovitsa Formation in the Pirin-Pangaion unit. Some discrepancies in the interpretations of the author in respect of the facts established by himself as well as to long-known geological information for the same rocks and locality are pointed at. We emphasize that the “monazite formation event” corresponds to the interval of ca. 62–24 Ma, i.e., to the whole time of Paleogene uplift of the unit and the intrusion and exhumation of the Spanchevo (ca. 57 Ma) and Teshovo (ca. 32 Ma) plutons. The pretended HP metamorphic event cannot be inscribed in this time span.

scholarly journals The measure matters: Language dominance profiles across measures in Spanish–English bilingual children

2012 ◽  
Vol 15 (3) ◽  
pp. 616-629 ◽  
Author(s):  
LISA M. BEDORE ◽  
ELIZABETH D. PEÑA ◽  
CONNIE L. SUMMERS ◽  
KARIN M. BOERGER ◽  
MARIA D. RESENDIZ ◽  
...  
Keyword(s):  
Language Proficiency ◽  
Full Range ◽  
Language Dominance ◽  
English Bilingual ◽  
Morphosyntactic Development ◽  
Comprehensive Picture ◽  
Short Test ◽  
Language Exposure ◽  
Language Measures ◽  
Different Levels

The purpose of this study was to determine if different language measures resulted in the same classifications of language dominance and proficiency for a group of bilingual pre-kindergarteners and kindergarteners. Data were analyzed for 1029 Spanish–English bilingual pre-kindergarteners who spanned the full range of bilingual language proficiency. Parent questionnaires were used to quantify age of first exposure and current language use. Scores from a short test of semantic and morphosyntactic development in Spanish and English were used to quantify children's performance. Some children who were in the functionally monolingual range based on interview data demonstrated minimal knowledge of their other languages when tested. Current use accounted for more of the variance in language dominance than did age of first exposure. Results indicate that at different levels of language exposure children differed in their performance on semantic and morphosyntax tasks. These patterns suggest that it may be difficult to compare the results of studies that employ different measures of language dominance and proficiency. Current use is likely to be a useful metric of bilingual development that can be used to build a comprehensive picture of child bilingualism.

The Duration and Geodynamics of Formation of the Angara–Vitim Batholith: Results of U–Pb Isotope (LA-ICP-MS) Dating of Magmatic and Detrital Zircons

2021 ◽  
Vol 62 (12) ◽  
pp. 1331-1349
Author(s):  
V.B. Khubanov ◽  
A.A. Tsygankov ◽  
G.N. Burmakina
Keyword(s):  
Drainage Basin ◽  
Detrital Zircons ◽  
Late Paleozoic ◽  
Metamorphic Rocks ◽  
Zircon Geochronology ◽  
Geochronological Data ◽  
Pb Isotope ◽  
Alluvial Deposits ◽  
Detrital Zircon Geochronology ◽  
Icp Ms

Abstract —We present results of U–Pb (LA-ICP-MS) dating of detrital zircons from the alluvial deposits of the Angarakan River (North Muya Ridge, northern Baikal region), whose drainage basin is composed mainly of granitoids of the Barguzin Complex, typomorphic for the late Paleozoic Angara–Vitim batholith (AVB). Three age clusters with peaks at 728, 423, and 314 Ma have been identified in the studied population of detrital zircons. It is shown that small outliers of igneous and metamorphic rocks, probably similar to the large AVB roof pendants mapped beyond the drainage basin, are the source of Neoproterozoic and early Paleozoic zircons. The late Paleozoic cluster comprises two close peaks at 314 and 28 Ma, which totally “overlap” with the time of the AVB formation and mark a granitoid source of the zircons. The results of detrital-zircon geochronology, together with the data on bedrocks, point to the prolonged (~40 Myr) formation of the AVB, but the intensity of magmatism during this period calls for additional study. Based on the analysis of published geological, geochemical, and geochronological data, we assume that the AVB resulted from the plume–lithosphere interaction that began in the compression setting and gave way to extension 305–300 Ma (the Carboniferous–Permian boundary), which caused replacement of “crustal” granitoids by granitoids formed from a mixed mantle–crustal source.

scholarly journals LA-ICP-MS and SIMS U-Pb and U-Th zircon geochronological data of Late Pleistocene lava domes of the Ciomadul Volcanic Dome Complex (Eastern Carpathians)

Data in Brief ◽  
2018 ◽  
Vol 18 ◽  
pp. 808-813 ◽  
Author(s):  
Réka Lukács ◽  
Marcel Guillong ◽  
Axel K. Schmitt ◽  
Kata Molnár ◽  
Olivier Bachmann ◽  
...  
Keyword(s):  
Late Pleistocene ◽  
Geochronological Data ◽  
Icp Ms ◽  
Eastern Carpathians ◽  
Lava Domes ◽  
Volcanic Dome
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