906 resultados para SAN MARTIN, JOSE DE


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The initial objective of Part I was to determine the nature of upper mantle discontinuities, the average velocities through the mantle, and differences between mantle structure under continents and oceans by the use of P'dP', the seismic core phase P'P' (PKPPKP) that reflects at depth d in the mantle. In order to accomplish this, it was found necessary to also investigate core phases themselves and their inferences on core structure. P'dP' at both single stations and at the LASA array in Montana indicates that the following zones are candidates for discontinuities with varying degrees of confidence: 800-950 km, weak; 630-670 km, strongest; 500-600 km, strong but interpretation in doubt; 350-415 km, fair; 280-300 km, strong, varying in depth; 100-200 km, strong, varying in depth, may be the bottom of the low-velocity zone. It is estimated that a single station cannot easily discriminate between asymmetric P'P' and P'dP' for lead times of about 30 sec from the main P'P' phase, but the LASA array reduces this uncertainty range to less than 10 sec. The problems of scatter of P'P' main-phase times, mainly due to asymmetric P'P', incorrect identification of the branch, and lack of the proper velocity structure at the velocity point, are avoided and the analysis shows that one-way travel of P waves through oceanic mantle is delayed by 0.65 to 0.95 sec relative to United States mid-continental mantle.

A new P-wave velocity core model is constructed from observed times, dt/dΔ's, and relative amplitudes of P'; the observed times of SKS, SKKS, and PKiKP; and a new mantle-velocity determination by Jordan and Anderson. The new core model is smooth except for a discontinuity at the inner-core boundary determined to be at a radius of 1215 km. Short-period amplitude data do not require the inner core Q to be significantly lower than that of the outer core. Several lines of evidence show that most, if not all, of the arrivals preceding the DF branch of P' at distances shorter than 143° are due to scattering as proposed by Haddon and not due to spherically symmetric discontinuities just above the inner core as previously believed. Calculation of the travel-time distribution of scattered phases and comparison with published data show that the strongest scattering takes place at or near the core-mantle boundary close to the seismic station.

In Part II, the largest events in the San Fernando earthquake series, initiated by the main shock at 14 00 41.8 GMT on February 9, 1971, were chosen for analysis from the first three months of activity, 87 events in all. The initial rupture location coincides with the lower, northernmost edge of the main north-dipping thrust fault and the aftershock distribution. The best focal mechanism fit to the main shock P-wave first motions constrains the fault plane parameters to: strike, N 67° (± 6°) W; dip, 52° (± 3°) NE; rake, 72° (67°-95°) left lateral. Focal mechanisms of the aftershocks clearly outline a downstep of the western edge of the main thrust fault surface along a northeast-trending flexure. Faulting on this downstep is left-lateral strike-slip and dominates the strain release of the aftershock series, which indicates that the downstep limited the main event rupture on the west. The main thrust fault surface dips at about 35° to the northeast at shallow depths and probably steepens to 50° below a depth of 8 km. This steep dip at depth is a characteristic of other thrust faults in the Transverse Ranges and indicates the presence at depth of laterally-varying vertical forces that are probably due to buckling or overriding that causes some upward redirection of a dominant north-south horizontal compression. Two sets of events exhibit normal dip-slip motion with shallow hypocenters and correlate with areas of ground subsidence deduced from gravity data. Several lines of evidence indicate that a horizontal compressional stress in a north or north-northwest direction was added to the stresses in the aftershock area 12 days after the main shock. After this change, events were contained in bursts along the downstep and sequencing within the bursts provides evidence for an earthquake-triggering phenomenon that propagates with speeds of 5 to 15 km/day. Seismicity before the San Fernando series and the mapped structure of the area suggest that the downstep of the main fault surface is not a localized discontinuity but is part of a zone of weakness extending from Point Dume, near Malibu, to Palmdale on the San Andreas fault. This zone is interpreted as a decoupling boundary between crustal blocks that permits them to deform separately in the prevalent crustal-shortening mode of the Transverse Ranges region.

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Detailed oxygen, hydrogen and carbon isotope studies have been carried out on igneous and metamorphic rocks of the Stony Mountain complex, Colorado, and the Isle of Skye, Scotland, in order to better understand the problems of hydrothermal meteoric water-rock interaction.

The Tertiary Stony Mountain stock (~1.3 km in diameter), is composed of an outer diorite, a main mass of biotite gabbro, and an inner diorite. The entire complex and most of the surrounding country rocks have experienced various degrees of 18O depletion (up to 10 per mil) due to interaction with heated meteoric waters. The inner diorite apparently formed from a low-18O magma with δ18O ≃ +2.5, but most of the isotopic effects are a result of exchange between H2O and solidified igneous rocks. The low-18O inner diorite magma was probably produced by massive assimilation and/or melting of hydrothermally altered country rocks. The δ18O values of the rocks generally increase with increasing grain size, except that quartz typically has δ18O = +6 to +8, and is more resistant to hydrothermal exchange than any other mineral studied. Based on atom % oxygen, the outer diorites, gabbros, and volcanic rocks exhibit integrated water/rock ratios of 0.3 ± 0.2, 0.15 ± 0.1, and 0.2 ± 0.1, respectively. Locally, water/rock ratios attain values greater than 1.0. Hydrogen isotopic analyses of sericites, chlorites, biotites, and amphiboles range from -117 to -150. δD in biotites varies inversely with Fe/Fe+Mg, as predicted by Suzuoki and Epstein (1974), and positively with elevation, over a range of 600 m. The calculated δD of the mid-to-late-Tertiary meteoric waters is about -100. Carbonate δ13C values average -5.5 (PDB), within the generally accepted range for deep-seated carbon.

Almost all the rocks within 4 km of the central Tertiary intrusive complex of Skye are depleted in 18O. Whole-rock δ18O values of basalts (-7. 1 to +8.4), Mesozoic shales (-0.6 to + 12.4), and Precambrian sandstones (-6.2 to + 10.8) systematically decrease inward towards the center of the complex. The Cuillin gabbro may have formed from a 18O-depleted magma (depleted by about 2 per mil); δ18O of plagioclase (-7.1 to + 2.5) and pyroxene (-0.5 to + 3.2) decrease outward toward the margins of the pluton. The Red Hills epigranite plutons have δ18O quartz (-2.7 to + 7.6) and feldspar (-6.7 to + 6.0) that suggest about 3/4 of the exchange took place at subsolidus temperatures; profound disequilibrium quartz-feldspar fractionations (up to 12) are characteristic. The early epigranites were intruded as low-18O melts (depletions of up to 3 per mil) with δ18O of the primary, igneous quartz decreasing progressively with time. The Southern Porphyritic Epigranite was apparently intruded as a low-18O magma with δ18O ≃ -2.6. A good correlation exists between grain size and δ18O for the unique, high-18O Beinn an Dubhaich granite which intrudes limestone having a δ18O range of +0.5 to +20.8, and δ13C of -4.9 to -1.0. The δD values of sericites (-104 to -107), and amphiboles, chlorites, and biotites (-105 to -128) from the igneous rocks , indicate that Eocene surface waters at Skye had δD ≃ -90. The average water/rock ratio for the Skye hydrothermal system is approximately one; at least 2000 km3 of heated meteoric waters were cycled through these rocks.

Thus these detailed isotopic studies of two widely separated areas indicate that (1) 18O-depleted magmas are commonly produced in volcanic terranes invaded by epizonal intrusions; (2) most of the 18O-depletion in such areas are a result of subsolidus exchange (particularly of feldspars); however correlation of δ18O with grain size is generally preserved only for systems that have undergone relatively minor meteoric hydrothermal exchange; (3) feldspar and calcite are the minerals mos t susceptible to oxygen isotopic exchange, whereas quartz is very resistant to oxygen isotope exchange; biotite, magnetite, and pyroxene have intermediate susceptibilities; and (4) basaltic country rocks are much more permeable to the hydrothermal convective system than shale, sandstone, or the crystalline basement complex.

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An area of about 25 square miles in the western part of the San Gabriel Mountains was mapped on a scale of 1000 feet to the inch. Special attention was given to the structural geology, particularly the relations between the different systems of faults, of which the San Gabriel fault system and the Sierra Madre fault system are the most important ones. The present distribution and relations of the rocks suggests that the southern block has tilted northward against a more stable mass of old rocks which was raised up during a Pliocene or post-Pliocene orogeny. It is suggested that this northward tilting of the block resulted in the group of thrust faults which comprise the Sierra Madre fault system. It is show that this hypothesis fits the present distribution of the rocks and occupies a logical place in the geologic history of the region as well or better than any other hypothesis previously offered to explain the geology of the region.

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O estudo desenvolvido nesta tese teve por intenção investigar a relação entre a questão da arte e a história do ser, tal como esta irá progressivamente se construir na obra de Martin Heidegger, sobretudo a partir de meados da década de 1930. Com isso, pretendeu-se identificar e destacar o papel fundamental que a abordagem desta questão deteve para a chamada viragem (Kehre) e os rumos posteriores da obra deste filósofo, conduzindo seu pensamento para além dos limites da analítica existencial empreendida em Ser e Tempo (1927) e em direção à construção da chamada "história do ser" e à questão do acabamento da metafísica como niilismo, na última fase de seu pensamento e em obras como o Beiträge zur Philosofie (1938). Para tal, partimos da investigação do ensaio A origem da obra de arte, publicado em meados da década de 1930, devido ao caráter central (não apenas em sentido cronológico) que esse texto ocupa para a abordagem do problema, posto nele Heidegger empreender a revisão de conceitos como Zuhandenheit e Vorhandenheit, de modo a assim abrir lugar, em sua ontologia, para este ente que a obra de arte é, com isso permitindo que o acontecimento do ser pudesse vir a ser pensando em novas bases e em perspectiva histórico-hermenêutica.

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Ondoren aurkezten den lana bi helburu nagusi ditu. Alde batetik, Etika Finantzarioak gaur egun duen egoera aztertzea, eta bestalde analizatzea egin diren ikerketak zertan zentratu diren. Horretarako, lan hau oinarrituko da 205 ISI artikuluetan, Leire San-José (UPV/EHU) irakasleak zuzendutako Delphi baten parte direnak. Beraz lan honen zati adierazgarriena bi bloke nagusitan bananduko da. Lehenengoan, artikuluetatik atera ahal diren datu guztiz teknikoak analizatuko dira, esate baterako: publikazio urtea, zein herrialdeetan idatzi diren, zein hizkuntzetan, etab; batez ere ondorengo galderei erantzuna eman ahal izateko: noiz ikertu da gehien? Zein herrialdeetan? Zein gaiei eman zaie garrantzia handiagoa?... Bigarren atalari dagokionez, Etika Finantzarioa osatzen duten gaien gehiengoei buruz egin diren ikerketen azalpen eta komentarioak jorratuko dira. Baina aurrekoaz aparte, mapa kontzeptual bat aurkeztuko da, gai honen azpi-gai eta kontzeptu klabe bilduz; eta horrela, modu argiago batean ikusi ahal izateko Etika Finantzarioa zertan datzan, zeintzuk diren bere barnean dauden gai garrantzitsuenak, eta zein faktore nagusiak dauden gai honetan. Azkenengoz, ondorio batzuk aurkeztuko dira, horien artean gai honek etorkizunean ikertzeko duen ibilbidea egongo delarik.

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The disposal of sewage is the most important item in public sanitation. It is the most important present day problem in every city whether large or small. The direct cause of the majority of epidemics is the contamination of the water supply of the city by the excreta of man or animal. Public health varies directly as public sanitation, and if the public sanitation be good, the liability of sickness caused by contamination of the water supply is greatly lessened. When a city outgrows its sewerage system the public health becomes endangered. There are two causes for the increased amount of sewerage, increase in population and increase in industrial and manufacturing wastes. The main problem in this connection is the ultimate disposal of the matter which reaches the sewers.

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The aim of this paper is to analyse the recent evolution of the city of San Francisco to outline the major features that have made it possible this continuing process of creative innovation in the city. In order to meet this objective, the project is framed around answering two key research questions: (1) what are the main economic and social elements that characterise urban change in the city of San Francisco and (2) which is the role of public strategies in the continuing economic success of San Francisco. The paper concludes that the successful performance of San Francisco is the result of the actions taken by many agents in the city, but the role of public authorities, especially the City and County, must be stressed, both through direct intervention and by coordinating, fostering and supporting the private and non-profit sectors. This is especially relevant in a country like the US where private initiative has been seen in many occasions as the greatest driver of economic and social success. Yet, the performance of San Francisco City cannot be explained without the role played by the public sector, in coordination with the civil society

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En el presente Trabajo Fin de Grado, se trabajará sobre la Red Básica Municipal de Donostia/San Sebastián, donde el autor ha sido partícipe en la campaña de reposición de la Red. Nos remontaremos a los orígenes de la Red, explicando cómo nació la Red Básica Municipal de Donostia/San Sebastián y la metodología que se usó para los trabajos previos a su implantación. A lo largo del trabajo, se explicará la metodología de observación y cálculo que se ha empleado en la actual reposición de la Red, el cual ha sido desarrollado por la empresa Geograma S.L. para el Ayuntamiento de San Sebastián entre enero y mayo de 2014. Finalmente, se estudiará como metodología alternativa las observaciones RTK en Red (NRTK), con el fin de validar el método para trabajos de observación de Redes Urbanas de Referencias Topográficas.

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ENGLISH: The Inter-American Tropical Tuna Commission (IATTC) operates under the authority and direction of a convention originally entered into by Costa Rica and the United States. The convention, which came into force in 1950, is open to adherence by other governments whose nationals fish for tropical tunas and tuna-like species in the eastern Pacific Ocean (EPO). Under this provision Panama adhered in 1953, Ecuador in 1961, Mexico in 1964, Canada in 1968, Japan in 1970, France and Nicaragua in 1973, Vanuatu in 1990, Venezuela in 1992, and EI Salvador in 1997. Mexico withdrew from the IATTC in 1978 and Canada in 1984. The 58th meeting of the IATTC was held in San Jose, Costa Rica, on June 3-4, 1997. SPANISH: La Comisión Interamericana del Atún Tropical (CIAT) funciona bajo la autoridad y dirección de un convenio suscrito originalmente por Costa Rica y los Estados Unidos de América. El convenio, vigente desde 1950, está abierto ala afiliación de cualquier país cuyos ciudadanos pesquen atunes tropicales y especies afines en el Océano Pacifico oriental (OPO). Bajo esta estipulación, la República de Panamá seafilió en 1953, Ecuador en 1961, México en 1964, Canadá en 1968, Japón en 1970, Francia y Nicaragua en 1973, Vanuatu en 1990, Venezuela en 1992, y El Salvador en 1997. México se retiro de la CIAT en 1978, y Canadá en 1984. La CIAT celebró su 58' reunión en San Jose de Costa Rica el 3 y 4 de junio de 1997. (PDF contains 310 pages.)

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Pasai San Pedroko Herrikoplaza-ko inguruaren birplanteaketa erabilera berrien integrazioaren eta irisgarritasunaren hobekuntzaren bidez.