Mobility of Morocco

1980 ◽  
Vol 17 (11) ◽  
pp. 1546-1558 ◽  
Author(s):  
Bertrand Sichler ◽  
Jean-Louis Olivet ◽  
Jean-Marie Auzende ◽  
Hélène Jonquet ◽  
Jean Bonnin ◽  
...  
Keyword(s):  
Atlantic Ocean ◽  
Magnetic Anomalies ◽  
Resolving Power ◽  
Virtual Geomagnetic Pole ◽  
Geomagnetic Pole ◽  
History Of ◽  
The Times ◽  
Central Atlantic ◽  
Early Phases ◽  
Limited Motion

The mobility of Morocco relative to Africa during the early history of the Atlantic has long been debated: arguments have been developed from Atlantic kinematic considerations and from paleomagnetic results. Both types of arguments are reexamined here. Using a new model of the Atlantic Ocean evolution described elsewhere, it is shown that the reconstructions of the positions of Africa relative to North America before the Atlantic opening, and at the times of magnetic anomalies M22 and J, do not imply a major motion of Morocco independent of Africa during these periods of time. The corresponding geomagnetic paleopoles have been recomputed from sample sites located on both "mobile" Morocco and "stable" Africa. The results indicate that the virtual geomagnetic pole of "mobile" Morocco for the Liassic falls within the 95% confidence cone of "stable" Africa. It is thus concluded that no major movement has occurred between "mobile" Morocco and "stable" Africa during the early phases of opening of the central Atlantic Ocean. This is in accordance with the field geological observations on the South Atlas fault; however, limited motion along this lineament, as observed in the field, is still compatible with the above conclusion, owing to the limited resolving power of both kinematic and paleomagnetic methods.

The use of paleomagnetic data to delineate the history of the development of the Connemara Antiform

1977 ◽  
Vol 14 (11) ◽  
pp. 2601-2613 ◽  
Author(s):  
W. A. Morris ◽  
P. W. G. Tanner
Keyword(s):  
Curie Point ◽  
Tectonic Evolution ◽  
Sufficient Time ◽  
Virtual Geomagnetic Pole ◽  
Tilt Correction ◽  
Correct Sequence ◽  
Geomagnetic Pole ◽  
History Of ◽  
Extreme Care ◽  
Gabbro Intrusion

The tectonic evolution of the Connemara Gabbro Suite as deduced from careful tilt correction of the initial remanence directions, and interpretation of locally reset magnetizations is substantially in agreement with that based on purely geologic criteria. Fold tests of remanence suggest the gabbro bodies acquired their remanence after the F3 folding phase but before the F4, Connemara Antiform folding phase, sometime between 440–490 Ma. After unfolding both limbs of the antiform so that the remanences of the two limbs coincide, an antiformal structure still remains. Therefore, the F3 hinge surfaces were not coplanar at the time of gabbro intrusion, and the Connemara Antiform had already begun to develop before the members of the gabbro suite had had sufficient time to cool below the Curie point. During the development of the F4, localized remagnetization occurred at two particular periods.It was not possible to obtain a unique remanence direction by 'unfolding' the limbs of the F4 antiform about its eastward plunging axis; a virtual geomagnetic pole cannot be quoted. Much of current paleomagnetic research is aimed at defining paleopole positions, so that in cases where they are required extreme care must be exercised in applying geologically appropriate tilt corrections, and where more than one correction is required, they must be applied in the correct sequence.

“Sou Inglesa! Sou Inglesa!”: Memórias de uma Menina Anglo-Portuguesa (1907-1930)

2017 ◽  
pp. 141-155
Author(s):  
Miguel Alarcão
Keyword(s):  
Everyday Life ◽  
Social History ◽  
Travel Literature ◽  
Growing Up ◽  
Recent Past ◽  
Self And Other ◽  
Cultural Encounter ◽  
The Social ◽  
History Of ◽  
The Times

Textualizing the memory(ies) of physical and cultural encounter(s) between Self and Other, travel literature/writing often combines subjectivity with documental information which may prove relevant to better assess mentalities, everyday life and the social history of any given ‘timeplace’. That is the case with Growing up English. Memories of Portugal 1907-1930, by D. J. Baylis (née Bucknall), prefaced by Peter Mollet as “(…) a remarkably vivid and well written observation of the times expressed with humour and not little ‘carinho’. In all they make excellent reading especially for those of us interested in the recent past.” (Baylis: 2)

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.

The Gastropod Genus Bembicium Philippi

1958 ◽  
Vol 9 (4) ◽  
pp. 546 ◽  
Author(s):  
H Anderson
Keyword(s):  
Early Summer ◽  
Egg Masses ◽  
Estuarine Species ◽  
History Of ◽  
Living Species ◽  
The Times

A history of the nomenclature of the littorinid genus, Bembicium Phllippi, 1846, and its characters are given, and the anatomy of species of the genus is discussed. Three species are recognized and redescribed: a reef-living species, B. nanum (Lamarck); an estuarine species, B. auratum (Quoy & Gaimard); and the species B. melanostoma (Gmelin) which normally inhabits sheltered bays and inlets. Although all are intertidal animals, and show some measure of adaptability, each appears to be best suited to a particular habitat. B. melanostoma and B. nanum are usually found where the chlorinity of the water is close to that of the sea. B. auratum can withstand considerable variation in the chlorinity of its environment for periods of time which are not likely to be exceeded in its normal habitat. B. melanostoma mostly lives at higher tidal levels than B. nanum. In the aquarium B. nanum proved the most susceptible to desiccation. The egg masses of B. melanostoma contain fewer and larger eggs than those of B. auratum. In the laboratory spawning of B. auratum occurred during the spring and early summer. Under the same conditions specimens of B. melanostoma deposited eggs in October. The differences between the eggs and their development, and between the times of spawning of the two species collected from different littoral regions are also discussed.

scholarly journals The history of pharmacy in Adamów

2016 ◽  
Vol 29 (2) ◽  
pp. 79-85
Author(s):  
Andrzej Wrobel ◽  
Malgorzata Korzeniowska ◽  
Agnieszka Polak ◽  
Marcin Szczygiel ◽  
Rafal Wrobel
Keyword(s):  
World War Ii ◽  
World War I ◽  
World War ◽  
History Of ◽  
The Times ◽  
Polish Intelligentsia ◽  
History Of Pharmacy

AbstractThis is one of a series of articles about pharmacists in Lublin district, in the 19th and 20th c. The first recorded owner of the pharmacy in Adamów was Aleksander Biernacki (1851-1897), who passed it onto his son-in-law, Aleksander Rogoziński (1873-1941), and who, in turn, passed it onto his son, Stanisław Rogoziński (1913-1998), married to Tatiana (1918-1998). This family's history is an example of the history of Polish intelligentsia in the second half of 19th c., in the times of the Russian partition, World War I, 1918-1939, World War II and until contemporary times.

Deveolpment of Constitutional Law on the Territory of Ukranie (IX-XIII Centuries)

2021 ◽  
pp. 1006-1014
Author(s):  
Oksana Pylypchuk
Keyword(s):  
Eighteenth Century ◽  
Constitutional Law ◽  
Political Regime ◽  
Democratic State ◽  
History Of ◽  
The Times ◽  
Grand Duchy Of Lithuania ◽  
History Of Formation ◽  
Grand Duchy ◽  
Submission Date

The article is devoted to the history of formation and development of Ukrainian constitutionalism. It is shown that during the times of Kievan Rus and the Galicia-Volyn principality monarchical states with elements of a democratic state and political regime were formed on Ukrainian lands. It is highlighted that the formation of the Ukrainian nation and its path to its own state was carried out under the conditions of aristocratic democracy of the Grand Duchy of Lithuania and the Polish-Lithuanian Commonwealth. It is emphasized that the Ukrainian people in the XV century became part of a large European society, which became the basis for the emergence of constitutional ideas in the Ukrainian ethnic lands, the creation of the Cossacks and the revival of their own Ukrainian state in the former Kievan Rus. It is noted that the results of the development of Ukrainian constitutionalism in the eighteenth century was presented in the Constitution of Hetman P. Orlyk in 1710, which became one of the most democratic constitutions in Europe at that time. Fecha de envío / Submission date: 25/02/2021 Fecha de aceptación / Acceptance date: 19/04/2021

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>

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