scholarly journals Geophysical monitoring of the Purace volcano, Colombia

1996 ◽  
Vol 39 (2) ◽  
Author(s):  
M. Arcila

Located in the extreme northwestern part of the Los Coconucos volcanic chain in the Central Cordillera, the Purace is one of Colombia's most active volcanoes. Recent geological studies indicate an eruptive history of mainly explosive behavior which was marked most recently by a minor ash eruption in 1977. Techniques used to forecast the renewal of activity of volcanoes after a long period of quiescence include the monitoring of seismicity and ground deformation near the volcano. As a first approach toward the monitoring of the Purace volcano, Southwest Seismological Observatory (OSSO), located in the city of Cali, set up one seismic station in 1986. Beginning in June 1991, the seismic signals have also been transmitted to the Colombian Geological Survey (INGEOMINAS) at the Volcanological and Seismological Observatory (OVS-UOP), located in the city of Popayan. Two more seismic stations were installed early in 1994 forming a minimum seismic network and a geodetic monitoring program for ground deformation studies was established and conducted by INGEOMINAS.

1921 ◽  
Vol 11 (1) ◽  
pp. 63-79
Author(s):  
Stephen Taber

Summary More than a hundred earthquakes have been recorded in southern California during the period February-September, 1920. These earthquakes have originated along several different faults in the vicinity of Los Angeles, but all of them are believed to have resulted from the adjustment of stresses set up in the region by the same general tectonic movements. The series of shocks felt in Los Angeles on July 16th originated along faults which cut Miocene and Pliocene rocks in the northern part of the city. The three strongest shocks on July 16th had epicentral intensities of between VI and VII in the Rossi-Forel scale; and they were felt over areas of from 500 to 2500 square miles. The known seismic history of southern California and the magnitude of the post-Pleistocene movements both indicate that the seismicity of the region is relatively high. There are many faults in the vicinity of Los Angeles; some of which are known to be active, while others are suspected of being active. Fortunately those within the city are short, while the longer ones are seven to thirty miles away, and are therefore less dangerous in so far as Los Angeles is concerned.


2007 ◽  
Vol 45 ◽  
pp. 66-72 ◽  
Author(s):  
Magnú s T. Guðmundsson ◽  
Þórdís Högnadóttir ◽  
Arnór Bergur Kristinsson ◽  
Snæbjörn Guðbjörnsson

AbstractThe Katla caldera is located under the Mýrdalsjökull ice cap and is one of the most hazardous volcanoes in Iceland due to major jökulhlaups that accompany eruptions. Subglacial geothermal activity is manifested in several 10–50m deep depressions (ice cauldrons) within and at the caldera rim and the total geothermal heat output is of the order of a few hundred megawatts. A short-lived but powerful pulse in geothermal heat output took place in 1999, probably including a minor subglacial eruption, when new ice cauldrons formed in three places and an unexpected jökulhlaup occurred. Following these events, a comprehensive monitoring program was set up for Katla, including ice surface elevation profiling from aircraft, to monitor variations in geothermal heat and detect signs of subglacial water accumulation. A radar altimeter coupled with a kinematic GPS is used, achieving an absolute elevation accuracy of 3m and internal consistency of 1–2 m. Profiles across the caldera are flown twice a year. An annual accumulation-ablation cycle in surface elevation with amplitude of 5–10m is observed. By removing this cycle from the data, changes due to subglacial geothermal activity are obtained. After the events in 1999, a decline in geothermal activity was observed. In 2001–03 some ice cauldrons expanded and deepened by 10–15 m, indicating renewed increase in geothermal activity. This trend is also apparent for 2003–05. The increase in geothermal power amounts to a few tens of megawatts. It is likely that the increased thermal output is related to increased seismicity and caused by magma inflow.


2012 ◽  
Vol 27 (1) ◽  
pp. 125-150
Author(s):  
ALBERTE MARTÍNEZ LÓPEZ ◽  
JESÚS MIRÁS-ARAUJO

ABSTRACTThe history of town gas is unique in the development of public services in urban areas. Indeed, gas was the subject of the first network infrastructure set up in cities. In Spain, its history is discontinuous because the networks were dismantled in the 1940s and 1950s. The purpose of this paper is to retrace the steps of the development of the gas network in a region where the Spanish gas companies took the form of early modern businesses. They contributed significantly to the dynamism of local financial markets, both in terms of enterprise configuration, technology dissemination and innovative management. However, the development of the gas industry remained subject to local conditions of supply and demand, to conflicts with local government and suffered from competition from electricity.


2011 ◽  
Vol 38 (1) ◽  
pp. 64-78
Author(s):  
Herwig Czech

AbstractThe Nazi drive for racial order led to the implementation of an authoritarian public health system which systematically subordinated the rights of the individual to the preventive protection of the Volksgemeinschaft. This article focuses on the example of Vienna in order to address the history of venereal disease control, public health politics towards prostitution and medical persecution of socially undesirable behavior under the influence of the biopolitical agenda of the Nazi regime. Combining sexual and racist motives, VD provided the regime with powerful images evoking a threat to the “purity” of the community. On one hand, forced laborers were subjected to a strict segregation from the local population because they personified the threat of infectious transgression. On the other hand, the concern with VD infections led to the stigmatization of women as sexually promiscuous and “antisocial.” At the same time, the authorities undertook the systematic reorganization of extramarital sex in the city. The network of brothels set up for this purpose not only served to minimize the dangers of VD; they channelled uncontrolled sexual activities by providing men with outlets for their sexual needs and by subjugating prostitution to the control of the authorities. This indicates that the whole realm of illicit sex was subjected to the principles of economic rationality, hygiene, discipline and visibility, thereby adding the brothel to the classic set of disciplinary institutions.


Author(s):  
G. Fangi

<p><strong>Abstract.</strong> What remains of Cultural Heritage in Syria? And in particular in Aleppo? Aleppo, according to UNESCO, is the oldest city in the world. The first settlements date back to 12,000 years ago, the first evidence of the city to 8,000. The A. visited the city in October 2018 at the invitation of the Syrian Trust for Development. He previously went to Syria for a photographic tour in 2010. It was a unique opportunity to document some noticeable buildings and monuments, later on affected by the war. When the war began in 2012, the A. retrieved the photographs and gave them to his students, who then ran some 28 projects of Cultural Heritage items. They are small monuments or small projects, neither complete not very accurate, but sometimes they are unique for the monuments that have already disappeared. In 2017 the book <i>Reviving Palmyra</i> was published, whose main author is the Finnish archaeologist Minna Silver. The book shows the results of the surveys of some monuments of Palmyra, including the Roman theater, the temple of Bel, the triumphal arch and the funerary tower of Al-Habel. The A. made an exibition of the these projects in Ancona, Italy, and produced a video of the exibition, which was then published online. Reme Sackr saw the video and invited the A. to visit Syria. She is a Syrian woman of the Syrian Trust for Development, a Syrian NGO for reconstruction of Syria. She is responsible for the Living Heritage Program inside the Trust, in practice responsible for the reconstruction and the restoration of the monuments in Syria. So in October 2018 the A. went to Aleppo, Syria, for a second time. The present paper shows some results and comparisons for same monuments before and after the war. The objects of the survey are some parts of the Citadel walls, the entrance tower of the Citadel, the southern tower, one mosque and the minaret of the Citadel mosque. One of the first monuments to be restored will be the minaret of the Great Omoyyad Mosque in Aleppo. Some monuments, the minority, are apparently in good condition, seemingly untouched by the war. Some are badly damaged and unsafe. They must first be made sade and subsequently restored. Finally, other monuments – and these are the majority – no longer exist because they have been destroyed to their very foundations. It seems that the war, besides the population, has particularly targeted monuments, perhaps because they represent the soul and history of a people and a country. For them the problem arises whether to reconstruct or not, and in case of reconstruction with which instruments and with which technique, if there are previous findings. This is precisely the case of the minaret. Here they will try to reconstruct the monument where it was, as it was and with the same materials, with possibly the same blocks in the same position they were in. For this task, however, their identification is necessary. The minaret is the most important monument in Syria, because it is the symbol of the country. It was built in 1092, and its restoration was completed in 2007. A special commission now follows the restoration work. It is composed by public, religious and technical-scientific authorities. They are the same university professors who carried out the restoration of 2007 and now curate the reconstruction. Work began in February 2018. The minaret stones were placed in the square of the mosque. Using a crane they raised the stones one by one, then photographed them from all positions. They then proceeded to the identification stage. A computer program was created in MATHLAB<sup>®</sup> which could carry out the first automatic selection of 6–8 possible candidates. The operator then manually selected the choosen one. Of the 1300 stones of the external face, 40&amp;thinsp;% have already been recognized. The high-resolution photographs of the A. of 2010 will help the identification. It is hoped to reach 70&amp;thinsp;%. Many blocks are no longer usable because they are broken, being limestone and therefore fragile. They no longer have the necessary resistance and will have to be replaced. A museum will be set up for the reconstruction of the minaret and the mosque. It is hoped to complete the work in two years. The surveying technique used by the A. is Spherical Photogrammetry. He published in 2018 <i>The book of Spherical Photogrammetry</i> a collection of related papers and experiences. This technique has been set up by the A. since 2006. It is based on spherical panoramas. These are cartographic representations on planes of spheres, on which the partially overlapping photographs taken from a single shooting point, are projected. Its main feature is the shooting speed. The technique is very much suitable for heritage documentation and the A. hopes to transfer it to the students of the local faculty of architecture. In this last mission, especially for the interiors, the A. made extensive use of Panono, a multi-image camera capable of covering 360°. These results prove undoubtedly that photogrammetry is an essential instrument for the 3D documentation and digital preservation of cultural heritage.</p>


2021 ◽  
pp. 026377582110626
Author(s):  
Caroline Keegan

In this paper, I develop a minor theory that blurs boundaries between prefigurative direct action and symbolic performance to reconsider strategies for resistance and world-building. Drawing on participant observation and interviews of economic justice organizers and activists in New Orleans in 2015, I examine two events through this minor theory: an immigration reform protest and a collaboratively written skit about income inequality. By emphasizing the performance of protest and the potential for protest through performance, I consider how these events empowered activists to make claims on spaces of the city, develop long-term embodied solidarities, disrupt dominant narratives, and en act more just alternatives. These events took place against the backdrop of intensifying racial and economic inequalities in post-Katrina New Orleans, following a long history of both repression and resistance in the city. Through performance-based direct actions, New Orleans’s economic justice movement moves beyond a reactive politics rooted in outrage and anguish toward a direct action politics constructive of a more just world.


2021 ◽  
Vol 12 (2) ◽  
pp. 228-246
Author(s):  
Gabriela Majewska

Plague city. Stockholm and the plague of 1710 The epidemic of plague in Stockholm between 1710 and 1711 was part of a great pandemic that devastated Eastern, Central, and Northern Europe in the first decade of the century and, at the same time, was the greatest demographic catastrophe in the history of the Swedish capital, as a result of which around 40% of the city’s population died. The first cases of plague appeared at the start of 1710; the peak of infections and deaths was in the autumn (October and November); in winter, the disease lessened and the last cases occurred in February 1711. It is estimated that the number of deaths reached 22,000. The suburbs and the poorest districts suffered most. Scarcity and famine, which struck Sweden at the end of the first decade of the XVIIIth century, fostered the rapid spread of the disease in the city and the high rate of mortality. The plague was also fostered by the effects of the war conducted by Charles XII and, particularly, the defeats suffered by the Swedish army and the seizure of the Baltic provinces by Peter the Great, which led to migrations from already plague-infected regions and worsened the already poor sanitary conditions in the city. Refugees from Estonia probably brought the plague to Stockholm. The Swedish authorities undertook measures against any epidemic as early as 1708 after receiving information about the spread of plague on the northern shores of the Baltic. These were limited to monitoring the movement of population. In 1709, quarantine was introduced for arrivals. After the first cases of plague in Stockholm regulations concerning people’s movements were made more strict, epidemic services were set up, and sanitary and public order directives were issued. Announcement of the plague was delayed until mid-September, when the number of deaths rose hugely, and it was obvious that the authorities were not in a position to control the spread of the epidemic. The city was closed, an ordinance against plague was issued regulating especially issues connected with health certificates, travel restrictions, maintaining cleanliness in houses and on the streets, compulsory registration and isolation of the sick, organization of interments, and the use of disinfectants and medicines. The reaction of the Stockholm authorities to the appearance of plague in the city reflected the actions of other Baltic cities struggling with plague at the same time.


2012 ◽  
Vol 4 (3) ◽  
pp. 232-239
Author(s):  
Rimkus Furuno ◽  
Mello de

The computational tools are evolving rapidly and continuously challenging the professionals involved in these technologies, which brings one to gain unmatched productivity and response, capable of reaching all strata of society. Today the challenge is to incorporate the human factor in this technological environment to achieve the results and low cost of deployment quickly. This work presents an ongoing study on the potential of these technologies to integrate the systems of documentation of historical and traditional build, with low implementation cost, a system for dissemination and preservation of the historical town of Laranjeiras (Sergipe - Brazil), forming specialized staff using the digital technologies applicable to the historical documentation. In this dynamic medium of exchange of information it is specifically proposed to evaluate the infrastructure involved and all the participants in the process. For this purpose a representative set of architectural history of the Laranjeiras city (Sergipe - Brazil), called the Trapiche's Quadroon, was selected and which was set up as a case study from which it has been intended to formulate guidelines to systematize information concerning the heritage of the city.


2009 ◽  
Author(s):  
Ferdinand Gregorovius ◽  
Annie Hamilton

2009 ◽  
Author(s):  
Ferdinand Gregorovius ◽  
Annie Hamilton

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