scholarly journals A re-evaluation of the Italian historical geomagnetic catalogue: implications for paleomagnetic dating at active Italian volcanoes

Solid Earth ◽  
2011 ◽  
Vol 2 (1) ◽  
pp. 65-74 ◽  
Author(s):  
F. D'Ajello Caracciolo ◽  
A. Pignatelli ◽  
F. Speranza ◽  
A. Meloni
Keyword(s):  
Geomagnetic Field ◽  
Substantial Agreement ◽  
Virtual Geomagnetic Pole ◽  
Before And After ◽  
Geomagnetic Pole ◽  
Paleomagnetic Dating ◽  
Original Observation ◽  
The 19Th Century ◽  
Westward Drift ◽  
Corrected Curve

Abstract. Paleomagnetism is proving to represent one of the most powerful dating tools of volcanics emplaced in Italy during the last few centuries/millennia. This method requires that valuable proxies of the local geomagnetic field (paleo)secular variation ((P)SV) are available. To this end, we re-evaluate the whole Italian geomagnetic directional dataset, consisting of 833 and 696 declination and inclination measurements, respectively, carried out since 1640 AD at several localities. All directions were relocated via the virtual geomagnetic pole method to Stromboli (38.8° N, 15.2° E), the rough centre of the active Italian volcanoes. For declination-only measurements, missing inclinations were derived (always by pole method) by French data (for period 1670–1789), and by nearby Italian sites/years (for periods 1640–1657 and 1790–1962). Using post-1825 declination values, we obtain a 0.46 ± 0.19° yr−1 westward drift of the geomagnetic field for Italy. The original observation years were modified, considering such drift value, to derive at a drift-corrected relocated dataset. Both datasets were found to be in substantial agreement with directions derived from the field models by Jackson et al. (2000) and Pavon-Carrasco et al. (2009). However, the drift-corrected dataset minimizes the differences between the Italian data and both field models, and eliminates a persistent 1.6° shift of 1933–1962 declination values from Castellaccio with respect to other nearly coeval Italian data. The relocated datasets were used to calculate two post-1640 Italian SV curves, with mean directions calculated every 30 and 10 years before and after 1790, respectively. The curve comparison suggests that both available field models yield the best available SV curve to perform paleomagnetic dating of 1600–1800 AD Italian volcanics, while the Italian drift-corrected curve is probably preferable for the 19th century. For the 20th century, the global model by Jackson et al. (2000) yields more accurate inclination values, while the declinations from our drift-corrected curve seem to better represent the local field evolution, at least for the first half of the century.

scholarly journals A re-evaluation of the Italian historical geomagnetic catalogue: implications for paleomagnetic dating at active Italian volcanoes

2011 ◽  
Vol 3 (1) ◽  
pp. 19-42
Author(s):  
F. D'Ajello Caracciolo ◽  
A. Pignatelli ◽  
F. Speranza ◽  
A. Meloni
Keyword(s):  
Geomagnetic Field ◽  
Data Sets ◽  
Virtual Geomagnetic Pole ◽  
Data Set ◽  
Before And After ◽  
Geomagnetic Pole ◽  
Paleomagnetic Dating ◽  
Corrected Data ◽  
Original Observation ◽  
Corrected Curve

Abstract. Paleomagnetism is proving to represent one of the most powerful dating tools of volcanics emplaced in Italy during the last few centuries/millennia. This method requires that valuable proxies of the local geomagnetic field (paleo)secular variation ((P)SV) are available. To this end, we re-evaluate the whole Italian geomagnetic directional data set, consisting of 833 and 696 declination and inclination (respectively) measurements carried out since 1640 AD at several localities. All directions were relocated via virtual geomagnetic pole method to Stromboli (38.8° N, 15.2° E), rough centre of the active Italian volcanoes. For declination-only measurements, missing inclinations were derived (always by pole method) by French data (for period 1670–1789), and by nearby Italian sites/years (for periods 1640–1657 and 1790–1962). Using post-1805 declination values, we obtain a 0.46 ± 0.19 °/yr westward drift of the geomagnetic field for Italy. Original observation years were modified considering such drift value to derive a drift-corrected relocated data set. Both data sets were found to be in substantial agreement with directions derived from the field models by Jackson et al. (2000) and Pavon-Carrasco et al. (2009). However, the drift-corrected data set minimizes the differences between the Italian data and both field models, and eliminates a persistent 1.6° shift of 1933–1962 declination values from Castellaccio with respect to other nearly coeval Italian data. The relocated data sets were used to calculate two post-1640 Italian SV curves, with mean directions calculated every 30 and 10 years before and after 1790, respectively. Curve comparison suggests that the regional model by Pavon-Carrasco et al. (2009) yields the best available SV curve to perform paleomagnetic dating of 1600–1800 AD Italian volcanics, while the Italian drift-corrected curve is probably preferable for the XIX century. For the XX century, the global model by Jackson et al. (2000) yields more accurate inclination values, while the declinations from our drift-corrected curve seem to better represent the local field evolution, at least for the first half of the century.

The paleomagnetism and U–Th dating of three Canadian speleothems: evidence for the westward drift, 5.4–2.1 ka BP

1982 ◽  
Vol 19 (10) ◽  
pp. 1985-1995 ◽  
Author(s):  
Alf. Latham ◽  
H. P. Schwarcz ◽  
D. C. Ford ◽  
G. W. Pearce
Keyword(s):  
Field Vector ◽  
Western Canada ◽  
Magnetic Signal ◽  
Virtual Geomagnetic Pole ◽  
Left Handed ◽  
Cave Deposits ◽  
Activity Ratios ◽  
Geomagnetic Pole ◽  
Dating Method ◽  
Westward Drift

Three speleothems from western Canada have been analyzed for their paleomagnetism and U–Th activity ratios. These cave deposits do not appear to show the kind of depositional effects on the recorded magnetic signal as is often the case with sediments. In addition the signal may be referred directly to geographic coordinates so that virtual geomagnetic pole plots may be constructed. This in turn has allowed assessment of any possible bias of the paleofield.The U–Th activity ratios of two flowstones from the Crowsnest Pass area of British Columbia indicated ages greater than the 350 ka dating limit of the dating method. One of the samples was reversely magnetized. Besides their use in the study of the ancient field, these samples have useful geomorphic applications. A stalagmite from Vancouver Island was shown to have recorded [Formula: see text] clockwise loops of the field vector in the period 5.4–2.1 ka BP. This implies a mainly westward drift of the paleofield for this period; the corresponding VGP's were mostly far-sided and slightly left-handed.

scholarly journals Lost in Migration – Mirandese at a Crossroads

2019 ◽  
Vol 5 (1) ◽  
pp. 488-495
Author(s):  
Cláudia Martins ◽  
Sérgio Ferreira
Keyword(s):  
Minority Language ◽  
Three Dimensions ◽  
Highly Qualified ◽  
Linguistic Rights ◽  
The Bible ◽  
Literary Forms ◽  
Before And After ◽  
The 1960S ◽  
The One ◽  
The 19Th Century

AbstractThe linguistic rights of Mirandese were enshrined in Portugal in 1999, though its “discovery” dates back to the very end of the 19th century at the hands of Leite de Vasconcellos. For centuries, it was the first or only language spoken by people living in the northeast of Portugal, particularly the district of Miranda do Douro. As a minority language, it has always moved among three dimensions. On the one hand, the need to assert and defend this language and have it acknowledged by the country, which proudly believe(d) in their monolingual history. Unavoidably, this has ensued the action of translation, especially active from the mid of the 20th century onwards, with an emphasis on the translation of the Bible and Portuguese canonical literature, as well as other renowned literary forms (e.g. The Adventures of Asterix). Finally, the third axis lies in migration, either within Portugal or abroad. Between the 1950s and the 1960s, Mirandese people were forced to leave Miranda do Douro and villages in the outskirts in the thousands. They fled not only due to the deeply entrenched poverty, but also the almost complete absence of future prospects, enhanced by the fact that they were regarded as not speaking “good” Portuguese, but rather a “charra” language, and as ignorant backward people. This period coincided with the building of dams on the river Douro and the cultural and linguistic shock that stemmed from this forceful contact, which exacerbated their sense of not belonging and of social shame. Bearing all this in mind, we seek to approach the role that migration played not only in the assertion of Mirandese as a language in its own right, but also in the empowerment of new generations of Mirandese people, highly qualified and politically engaged in the defence of this minority language, some of whom were former migrants. Thus, we aim to depict Mirandese’s political situation before and after the endorsement of the Portuguese Law no. 7/99.

scholarly journals Paleomagnetic study of basaltic rocks from Baengnyeong Island, Korea: efficiency of the Tsunakawa–Shaw paleointensity determination on non-SD-bearing materials and implication for the early Pliocene geomagnetic field intensity

2019 ◽  
Vol 71 (1) ◽  
Author(s):  
Hyeon-Seon Ahn ◽  
Yuhji Yamamoto
Keyword(s):  
Dipole Moment ◽  
Mean Value ◽  
Good Precision ◽  
Dipole Strength ◽  
Virtual Geomagnetic Pole ◽  
Early Pliocene ◽  
Basaltic Rocks ◽  
Geomagnetic Pole ◽  
Bearing Materials ◽  
Fitting In

AbstractFinding the statistical intensity signatures of the Earth’s magnetic field over geologic time has helped understanding of the evolution of the Earth’s interior and its interactions with other integral parts of Earth systems. However, this has been often hampered by a paucity of absolute paleointensity (API) data, which are difficult to obtain primarily because of non-ideal magnetic behaviors of natural materials. Here, we present new API determination data with paleodirectional and rock magnetic analyses from basaltic rocks probably aged ~ 4‒5 Ma in Baengnyeong Island, Korea. Paleodirectional analysis obtained an overall mean direction of D = 347.3° and I = 38.3° (α95 = 4.9°, k = 113.4) corresponding to a virtual geomagnetic pole at 342.1° E and 70.2° N. Comprehensive rock magnetic analyses identified Ti-poor titanomagnetite with, in part, multi-domain (MD) particles as a main carrier of remanent magnetization. The Tsunakawa–Shaw (TS) method yielded 12 qualified API estimates with a high success rate, efficiently removing possible MD influences, and resulted in a mean value of 13.1 μT with good precision (1.7 μT, standard deviation). The Thellier method of the IZZI protocol with pTRM checks, coupled with the use of a bootstrap approach instead of the “conventional best-fitting” in API determination, gave 6.6‒19.7 μT as a 95% confidence interval of its mean API estimate, which supports the reliability of our TS-derived API mean estimate; but it is not considered in the final mean value because of the relatively large uncertainty. The virtual dipole moment corresponding to the TS-derived API mean, 2.9 (± 0.4) × 1022 Am2, is somewhat lower than the expectations of the past few Myr averages. Combined with a global API database, our new data implies a larger dispersion in the dipole moment during the early Pliocene than previously inferred. This also suggests that the issue of whether the early Pliocene average dipole strength was moderately high (> 5 × 1022 Am2) or consistent (4‒5 × 1022 Am2) should be discussed further.

scholarly journals Characterization and Identification of Varnishes on Copper Alloys by Means of UV Imaging and FTIR

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 298
Author(s):  
Miriam Truffa Giachet ◽  
Julie Schröter ◽  
Laura Brambilla
Keyword(s):  
Copper Alloys ◽  
Analytical Techniques ◽  
Experimental Methodology ◽  
Artificial Ageing ◽  
Non Invasive ◽  
Uv Imaging ◽  
Before And After ◽  
The Comparative Study ◽  
The 19Th Century ◽  
Analytical Tools

The application of varnishes on the surface of metal objects has been a very common practice since antiquity, both for protective and aesthetic purposes. One specific case concerns the use of tinted varnishes on copper alloys in order to mimic gilding. This practice, especially flourishing in the 19th century for scientific instruments, decorative objects, and liturgical items, results in large museum collections of varnished copper alloys that need to be preserved. One of the main challenges for conservators and restorers deals with the identification of the varnishes through non-invasive and affordable analytical techniques. We hereby present the experimental methodology developed in the framework of the LacCA and VERILOR projects at the Haute École ARC of Neuchâtel for the identification of gold varnishes on brass. After extensive documentary research and analytical campaigns on varnished museum objects, various historic shellac-based varnishes were created and applied by different methods on a range of brass substrates with different finishes. The samples were then characterized by UV imaging and infrared spectroscopy before and after artificial ageing. The comparative study of these two techniques was performed for different thicknesses of the same varnish and for different shellac grades in order to implement an identification methodology based on simple non-invasive examination and analytical tools, which are accessible to conservators.

Geochronological and paleomagnetic studies of small carbonatite intrusions of the Udzha uplift (Tomtor massif, northeast of the Siberian platform)

2021 ◽  
Author(s):  
Aleksandr Pasenko ◽  
Ivanov Alexey ◽  
Malyshev Sergey ◽  
Travin Alexey
Keyword(s):  
Siberian Platform ◽  
Conclusive Evidence ◽  
Snowball Earth ◽  
Paleomagnetic Data ◽  
Russian Science ◽  
Virtual Geomagnetic Pole ◽  
River Bank ◽  
High Temperature Component ◽  
Geomagnetic Pole ◽  
Temperature Component

<p>Paleomagnetic data obtained from Neoproterozoic glacial and glacier-associated sedimentary rocks indicate that they were formed at near equatorial latitudes. Based on these data, the Snowball Earth hypothesis was proposed [Kirschvink, 1992]. According to this hypothesis, during the Neoproterozoic glaciations, the entire planet (including the oceans) was completely covered with ice. Although evidence is emerging that does not support this hypothesis, there is still no conclusive evidence that it is not true [Sansjofre et al., 2011].</p><p>It is worth noting that the Snowball earth hypothesis is based on paleomagnetic data. At the same time, the available paleomagnetic data for the Neoproterozoic-Early Cambrian [Meert, Van der Voo, 2001; Shatsillo et al, 2005; Abrajevitch, Van der Voo, 2010; Pavlov et al., 2018] difficult to interpret in terms of the Geocentric Axial Dipole hypothesis. This imposes serious restrictions on the possibility of correctly constructing paleomagnetic reconstructions.</p><p>For the development and testing of a model of the geomagnetic field of the Neoproterozoic, it is necessary to obtain a lot of high-quality paleomagnetic data. Data from well-dated magmatic bodies are especially valuable.</p><p>Within the framework of this work, we obtained paleomagnetic data from three carbonatite dikes (7 to 30 cm thickness) exposed in the Udzha river bank on the Udzha uplift in the northeastern part of the Siberian platform. These dikes are associated with the large alkaline Tomtor massif located 15 km to the west. Ar/Ar dating of phlogopite megacrysts gives an intrusion age of the dikes of 706.1±8.8 Ma. Coordinates of the virtual geomagnetic pole, calculated from the direction of the high-temperature component of magnetization: Φ=-20.7°; Λ=88.6°; Α95=3.4°.</p><p>Our report will present preliminary interpretation of these data, as well as their comparison with paleomagnetic data on close-aged objects in Siberia.</p><p><em>The research was supported by the Russian Science Foundation grant (19-77-10048).</em></p><p>References:</p>

scholarly journals Leucistic Woodcock (Scolopax rusticola L.) occurrences in Hungary from the second half of the 19th century to the present day

2019 ◽  
Vol 27 (2) ◽  
pp. 100-114
Author(s):  
Attila Bende ◽  
Angéla Király ◽  
Richárd lászló
Keyword(s):  
Large Scale ◽  
Sample Collection ◽  
Hungarian Literature ◽  
Scolopax Rusticola ◽  
Large Scale Analysis ◽  
Genetic Abnormalities ◽  
Before And After ◽  
Colour Changes ◽  
The 19Th Century ◽  
White Colour

Abstract Publications about curiosities are known in the Hungarian and international ornithological literature since the 1800s. Although studies explaining the processes of pigmentation dysfunctions have been known since the mid-nineteenth century, these specimens still appear only as curiosities in the professional press and the terminology used to specify them is generally incorrect. The analysed genetic abnormalities causing white colour varieties in Woodcock (albinism, leucism, Ino) are due to mutations. By briefly describing the biological background of the defects, this work helps detect colour changes. In this article, we provide a broad overview of partially or completely white Woodcocks (n = 23 expl.) found in international (8 countries) and Hungarian literature. We have supplemented the literature background with our own studies. The large-scale analysis of the variability of colours and patterns was made possible by the countrywide wing sample collection within the biometric module of Woodcock Monitoring, which has been running under the coordination of the Hungarian Hunting Conservation Association since 2010. Within this framework, 12,078 samples were analysed between 2010–2018. We found that pigment deficiency occurred in the sample set only with a proportion of 0.01%. Based on the Hungarian literature and our own samples, we presented the known occurrences on maps of the state territory with boundaries before and after 1921, indicating the causes of patterns of occurrence by migration and frequencies of occurrence.

Hegel, China, and the 19th Century Europeanization of Philosophy

2018 ◽  
Vol 45 (1-2) ◽  
pp. 18-37
Author(s):  
Justin E. H. Smith
Keyword(s):  
19Th Century ◽  
Chinese Philosophy ◽  
Western Philosophy ◽  
Late 19Th Century ◽  
Nationalist Discourse ◽  
Before And After ◽  
The 19Th Century ◽  
The Way

I clarify Hegel’s role in the Europeanization of philosophy over the course of the 19th century. I begin with an investigation of the way non-Western philosophy was conceptualized in Europe before, and after, I move on to a consideration of the debates about philosophy that emerged in late 19th century China because of European attempts, such as that of Hegel, to circumscribe the geographical and civilizational scope of this discipline. How may we see the emergence of a distinctly modern, generally nationalist, discourse about “Chinese philosophy” within China as a reflection of larger global processes then taking place?

CULTURE OF TURKISTAN IN THE SECOND HALF OF THE XIX CENTURY

2021 ◽  
Vol 4 (7) ◽  
pp. 15-22
Author(s):  
Zebiniso A. Akhmedova ◽  
Keyword(s):  
19Th Century ◽  
Social Economic ◽  
Diplomatic Relations ◽  
Political Situation ◽  
Cultural Life ◽  
The Social ◽  
Before And After ◽  
Xix Century ◽  
The 19Th Century ◽  
The Military

The article analyzes the culture of Turkestan in the second half of the 19th century. The social, economic, politicaland cultural life of Bukhara during the Mangit dynasty is revealed. Clarified trade and diplomatic relations between Bukhara and Russia.On the basis of the works of Ahmad Donish, the economic and political situation in Bukhara, as well as relations with neighboring countries, are studied. The author draws attention to the military-bureaucratic colonial system of tsarism in Turkestan and reveals the reasons for the emergence of ideas of national liberation in the country. Examples are used to analyze the life of Bukhara before and after the invasion of tsarism

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