Differences in the rupture process for very deep earthquakes at the Peru-Brazil and Peru-Bolivia borders 

Author(s):  
Elisa Buforn ◽  
Carmen Pro ◽  
Hernando Tavera ◽  
Agustin Udias ◽  
Maurizio Mattesini

<p>We analyze the differences in the rupture process for twelve very deep earthquakes (h>500 km) at the Peruvian-Brazilian subduction zone. These earthquakes are produced by the contact between the Nazca and the South America Plates. We have estimated the focal mechanism from teleseismic waveforms, using the slip inversion over the rupture plane, testing rupture velocities ranging from 2.5 km/s to 4.5 km/s, and analyzing the slip distribution for each  rupture velocity. The selected 12 earthquakes have occurred in the period 1994- 2016, with magnitudes between 5.9 and 8.2 and focal depth 500- 700 km. They can be separated in two groups attending to their epicentral location. The first group is formed by 9 events located, in the Peruvian-Brazil border, with epicenters following a NNW-SSE alignment, parallel to the trench. Their focal mechanisms present solutions of normal faulting with planes oriented in NS direction, dipping about 45 degrees and with vertical pressure axis. The second group is formed by three earthquakes located to the south of the first group in northern Bolivia. Their mechanisms show dip-slip motion with a near vertical plane, oriented in NW-SE direction and the pressure axis dipping 45º to the NE. The moment rate functions correspond to single ruptures with time durations from 6s to 12s, with the exception of the large 1994 Bolivian earthquake (Mw = 8.2) which presents a complex and longer STF. The different mechanisms for the two groups of earthquakes confirm the different dip of the subducting Nazca plate at the two areas, with the steeper part at the southern one.  </p>

2020 ◽  
Author(s):  
Carolina López Sánchez ◽  
Elisa Buforn ◽  
Maurizio Mattesini ◽  
Hernando Tavera

<p>The seismicity of Peru is associated with the subduction process of the Nazca plate under South America and characterized by the occurrence of shallow, intermediate and deep earthquakes. In this study, we focus our attention on the rupture process of earthquakes (Mw>6.0 ) that occurred during the period 2018-2019 at intermediate depth (50<h<200 km) and deep depth (500<h<700 km). Focal mechanisms have been estimated from slip inversion of body waves at teleseismic distances (Kikuchi and Kanamori, 1991). We investigate possible differences in the moment rate functions at different focal depths using our results and those provided by SCARDEC database. Furthermore, an estimation of the radiated seismic energy (E<sub>R</sub>) was provided from the direct integration of the velocity P wave recorded at teleseismic and regional distances, getting values between 10<sup>15 </sup>to 10<sup>16</sup> J. The data were corrected by geometrical spreading, anelastic attenuation, and free surface effect. These results are interpreted in terms of the seismotectonics of the region</p>


2018 ◽  
Vol 38 (2) ◽  
pp. 255-286
Author(s):  
Sam Edwards

This article examines how a post-1918 Edwardian commemorative aesthetic focused on the “English Garden” was deployed in the later twentieth century as a means to establish an “informal” Empire of memory. The result is an architectural irony and a landscape at odds with the moment that made it: the post-1945 cemeteries of the Imperial War Graves Commission (IWGC) expanded the now defunct Empire’s commemorative possessions just as the actual deeds to land were surrendered. The one exception to this story of contemporaneous political withdrawal and commemorative appropriation nonetheless proves the broader point. For after the bloody imperial war fought in the South Atlantic in 1982 the Commission, at the behest of the British government, built its first and last post-1945 overseas war cemetery. And just as had been the case sixty years earlier, the form and style of this cemetery ensured it became the last outpost of an Edwardian Empire of memory.


2021 ◽  
Vol 1 (1) ◽  
pp. 60-75
Author(s):  
Suradi Suradi ◽  

The Population and Civil Registration Office of South Lampung Regency is one of the South Lampung Regency Government Agencies that directly provides public services, as stated in the Decree of the South Lampung Regent Number 11 of 2003 concerning the Job Description of the Office of Population and Civil Registration of South Lampung Regency. In connection with the foregoing, the Department of Population and Civil Registration of South Lampung Regency has the responsibility to carry out the said public service which is also based on the goal of excellent service in order to create good governance. Community satisfaction in receiving service from the service is measured by understanding the dimensions of service quality that are closely related to community satisfaction, namely tangiables (physical evidence), relianility (reliability), responsiveness (responsiveness), assurance (guarantee) and empathy. The purpose of this study was to determine the forms of financial motivation implemented at the Department of Population and Civil Registration of South Lampung Regency, therefore the hypothesis proposed in this study was "There is a positive influence between financial motivation on employee performance". Meanwhile, the data collection method used is the method of observation, interviews, documentation and questionnaires. While the analysis used is qualitative and quantitative. From the calculation of the data analysis, it is obtained that r count 0.899 when consulted with the r value of the moment product label for N 49 both at a significant level of 5% = 0.325 and a significant level of 1% = 0.418 turns out that r count is greater than r table or r 0.899 > 0.325 and 0.899 > 0.418. Thus, it can be shown that there is a positive relationship between financial motivation and employee performance at the Department of Population and Civil Registration of South Lampung Regency. In other words, the better the financial motivation by the leadership to subordinates or employees, the better the employee's work performance will be. Keywords: financial motivation, employee achievement, population and civil registration services


2020 ◽  
Author(s):  
Constanza Rodriguez Piceda ◽  
Magdalena Scheck-Wenderoth ◽  
Maria Laura Gómez Dacal ◽  
Judith Bott ◽  
Claudia Prezzi ◽  
...  

<p>The Andean orogeny is a ~7000 km long N-S trending mountain range developed along the South American western margin. The formation of this mountain range is driven by the subduction of the oceanic Nazca plate beneath the continental South American plate, being the only known present-day case of subduction-type orogeny. In this tectonic setting, the intrinsic physical properties of the overriding plate govern the formation of zones of crustal strength and weakness and control the localization and the style of deformation. Furthermore, the dynamics of the subducting oceanic lithosphere is strongly conditioned by the properties of the continental counterpart. The southern segment of the Central Andes (29°S-39°S) is a suitable scenario to investigate the relationship between the two plates for several reasons. It is characterized by a complex deformation pattern with variations in horizontal shortening, crustal thickening and mean topographic elevation. In addition, the subduction angle changes at 33°S-35°S latitude from flat in the North to normal in the South. To gain insight into this geodynamic system, a detailed characterization of the lithosphere is needed. Therefore, we constructed a 3D model of the entire segment of the Southern Central Andes that is consistent with the available geological, seismic and gravity data in order to assess the geometry and density variation within the lithosphere. The derived configuration shows a spatial correlation between density domains and known tectonic features. It is also consistent with other independent observations such as S wave velocity variation and surface deformation. The generated structural model allows us to reach the first conclusions about the relationship between the characteristics of the overriding plate and the crustal deformation and dynamics of the subduction system. It is also useful to constrain thermomechanical experiments and therefore contributes to discussions about the crustal thermal and rheological fields within the region.</p>


1957 ◽  
Vol 94 (2) ◽  
pp. 89-103 ◽  
Author(s):  
C. B. Crampton

AbstractThe great majority of Moine lineations are mica structures, and together with a parallel preferred orientation of epidote [010]-axes, are directed mainly into the south-east quadrant. This orientation is retained within the crush zone alongside the Moine Thrust. The regional preferred orientation of muscovite [100]-axes and [001]-axes is consistent with north-east and south-west movements except within the crush zone where fabric reorientation suggests movements normal to this direction. The growth of albite textures and fabric is intimately associated with thrust plane movements, the preferred orientation of albite suggesting a south-east and north-west vertical plane of deformation.


2019 ◽  
Author(s):  
Eugenio E. Vogel ◽  
Felipe G. Brevis ◽  
Denisse Pastén ◽  
Víctor Muñoz ◽  
Rodrigo A. Miranda ◽  
...  

Abstract. Four geographical zones are defined along the trench that is formed due to the subduction of the Nazca Plate underneath the South American plate; they are denoted A, B, C and D from North to South; zones A, B and D have had a major earthquake after 2010 (8.0), while zone C has not, thus offering a contrast for comparison. For each zone a sequence of intervals between consecutive seisms with magnitudes ≥ 3.0 is formed and then characterized by Shannon entropy and mutability. These methods show correlation after a major earthquake in what is known as the aftershock regime but they show independence otherwise. Exponential adjustments for these parameters reveal that mutability offers a wider range for the parameters characterizing the recovery to the values of the parameters defining the background activity for each zone before a large earthquake. It is found that the background activity is particularly high for zone A, still recovering for Zone B, reaching values similar to those of Zone A in the case of Zone C (without recent major earthquake) and oscillating around moderate values for Zone D. It is discussed how this can be an indication for more risk of an important future seism in the cases of Zones A and C. The similarities and differences between Shannon entropy and mutability are discussed and explained.


2014 ◽  
Vol 1 ◽  
pp. 89-109
Author(s):  
Marcin Mikołajczyk

Greek diaspora in Poznan in the 18th and 19th century Poznań, one of the largest Polish cities, was frequently inhabited by citizens of other countries. One such nation were Greeks, who came to Poland for economic, political and geopolitical reasons. Ethnic origins of emigrants remains an interesting problem. The first information on Greeks in Poznań can be traced back to the 16th century. In the second half of the 17th century, the number of Greeks coming to the city increased. Emigrants occupied themselves mainly with (profitable) wine and Eastern goods trade. Greeks imported wine mostly from Hungary. From the moment they came, Greeks were considered unwelcome by local tradesmen. Municipal books and the books of the Merchants’ Guild are full of complaints on the incomers from the South. It was not until 1789, when the laws of the Commission of Good Order operating in Poznań, that the conditions of Greeks staying in Poznań had been regulated. The Poznań Greek community was established around 1750. Poznań Greeks were of the Christian Orthodox denomination. Services were held at home churches, the community also had its cemetery. The following people were the chaplains: Atanazy Korda, Konstantyn Chartofilax Okuta, Atanazy Sawicz and Zupanos. The Poznań Greek community was dissolved in 1909. The most well-known representative of the Poznań Greeks is Jan Konstanty Żupański, a bookseller and publisher.


2021 ◽  
Vol 7 ◽  
pp. 40-53
Author(s):  
T.N. Surin

The relevance of the work is caused by necessary regional analysis of magmatic evolution of the East Magnitogorsk belt and refnement of ideas on geodynamics of the South Urals. The geology and petrochemical-mineralogical features of the Sakhara dunite-clinopyroxenite-gabbro complex in the South Urals are characterized in the paper. Its late Frasnian age is substantiated. The composition of olivine, clinopyroxene and chromite in rocks of the complex are determined. The restite nature of dunites is proved. It is shown that rocks of the complex are similar to those of the Urals platinum belt and belong to Ural-Alaskan type. It is concluded that the complex formed in island-arc geodynamic setting and in the beginning of the formation of a mature island arc. The location of massifs of the complex is an additional argument in favor of a western dip (in the present-day coordinates) of a subduction paleozone at the moment of its formation. Crystallization diferentiation was a leading mechanism of petrogenesis of rocks of the complex.


Author(s):  
Katarina Mitrovic ◽  
Marija Koprivica

After two centuries of Bulgarian domination, Belgrade came under Byzantum empire rule in 1018. Together with other fifteen cities, Belgrade was mentioned as a bishop centre in a thorough act of the Ohrid Archbishopric, the first sigilion of Tzar Vasilije II Macedonian, from 1019. Belgrade episcopate also comprised Church centres in Gradac, Uzice, Bela Crkva and Glavetin with 40 clergymen and 40 village mayors, which means that it was one of the richest diocese of the Ohrid Archbisopric. Since Belgrade came under Byzantium rule, there have not been any big changes in the character of Church authorities as the Ohrid Archdiocese was established on the spiritual and cultural traditions of The first Bulgaran empire and Samuil`s state, its head was called an archbishop of Bulgaria and in terms of jurisdiction, it was completely independent of Contantinople patriarch. Short reign of Hungarian king Salomon in Belgrade (1071/72) did not lead to any changes in Church organistaion, although certain bishop Franco was mentioned by the King`s counselors. The consolidation of the Catholic Church organisation was enabled only from the fourth decade of the XIII century when Belgrade belonged to the Hungarian king. No later than the beginning of March 1232, according to the decision of the Pope Gregory IX of the Orthodox Eparchy, Belgrade and Branicevo were united with the newly established Episcopate of Syrmia which was founded as a missionary one with the clearly defined aim of the spread of Catholicism among the population of the other part of Syrmia (the regions on the south of the Sava, between the rivers of Drina and Kolubara) which, not long time ago, had been a part of the Diocese of Syrmia under the jurisdiction of the Ohrid Archbishopric. In the period of 1284-1389, Belgrade was under Serbian rule. King Dragutin built the Temple, the headquarters of the bishop of Macva of Serbian Church with the famous Icon of the Most Holy Mother of God, a well-known relic from the period of Byzantium rule, and some other churches, so there were many Orthodox priests in Belgrade and its surroundings. Episcopate of Macva Serbian Church was established in the period of 1284-1290, and it was situated on the country of Macva, i.e. Syrmia. The river Sava was on its northern border, the river of Drina was on the western one, while the Kolubara and the slopes of Avala and Kosmaj were on the eastern border, and the territory reached Crna Gora and Rudnik on the south. Its territory covered the regional unit of Macva only partially. On the basis of the data written down by the Archbishop Danilo II, an expert in Church issues of the time, it is quite uncertain whether there was a metropolitan`s residence in Belgrade. In order to solve the puzzle, some hypotheses were outlined in the reference to the political circumstances and Church practices. The firmly established organisation of the Serbian Church endangered the rights of Belgrade Diocese of the Roman Church; that is why the pope Nicholas IV (1288-1292) and John XXII (1316-1334) reacted in order to establish the Catholic jurisdiction. Although Belgrade bishops Martin and Benedict were mentioned in Latin sources from the nineties of the XIV century, Albensis capitulum, Magister Theodor Albensis Ecclesie Prepositus, Magister Demetrius Canonicus Albensis, those were only titlings. The moment of the formal establishment of the already founded clerical organisation was patiently awaited for. It happened after Belgrade had fallen under Hungarian rule again. Hungarian king Charles Robert was active in the strengthening of the position of the Roman Church. After 1319, the headquarters of the Macva bishop was relocated from Belgrade, but the Episcopate of Macva of the Serbian Church seemed to have continued its activities. The counties of Ub, Nepricava, Rabas, Pepeljevac, Ljig, Toplica, Upper and Lower Obna and the region of Crna Gora and Rudnik were under its jurisdiction, undoubtedly under the authority of the Serbian King. Most likely the Serbian bishop of Macva also had jurisdiction over the Orthodox clergy and the religious people in the regional units of Macva which were returned to Hungary in 1319.


1915 ◽  
Vol 9 ◽  
pp. 1-20 ◽  
Author(s):  
C. H. Firth

When I remembered that I had to address the Society to-day I thought at first of choosing some subject remote from the troubles of the moment, something analogous to my former addresses on the development of historical studies in England. But it was not possible to do so. The events which are in progress now have too absorbing an interest to permit us to abstract ourselves from them, for which of us is not in some way or other intimately affected by them? Besides that, these events have for any historian not merely the interest which all of us share, but an interest of a very special kind. The historian sees in action before his eyes the abstractions he has been reading about in books all his life: the struggle of races, the conflict of opposing ideas, the operation of economic laws, the development of historical tendencies, and perceives what these phrases really mean when they are translated into facts. There has been no such open conflict of ideals since the wars of the French Revolution. There has been no such huge conflict of races since the time when the Teutonic peoples moved westward to overthrow Roman civilisation and plant their own in its place. One of Milton's similes for the Satanic host pictures their coming:‘A multitude like which the populous North Poured never from her frozen loins to pass Rhene or the Danaw, when her barbarous sons Came like a deluge on the South, and spread Beneath Gibraltar to the Libyan sands.’


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