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An Approach Using Synthetic Seismograms and Newmark Analysis

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An Approach Using Synthetic Seismograms and Newmark Analysis PONTIFICIA UNIVERSIDAD CATOLICA DE CHILE ESCUELA DE INGENIERIA CO-SEISMIC LANDSLIDES: AN APPROACH USING SYNTHETIC SEISMOGRAMS AND NEWMARK ANALYSIS. CASE STUDY: COASTAL RANGE OF VALPARAÍSO, CHILE DOMINIQUE D. VALDIVIA LARENAS Thesis submitted to the Office of Research and Graduate Studies in partial fulfillment of the requirements for the Degree of Master of Science in Engineering Advisor: CARLOS MARQUARDT ROMÁN Santiago de Chile, (December, 2020) © 2020, Dominique Valdivia PONTIFICIA UNIVERSIDAD CATOLICA DE CHILE ESCUELA DE INGENIERIA CO-SEISMIC LANDSLIDES: AN APPROACH USING SYNTHETIC SEISMOGRAMS AND NEWMARK ANALYSIS. CASE STUDY: COASTAL RANGE OF VALPARAÍSO, CHILE DOMINIQUE DE LOURDES VALDIVIA LARENAS Members of the Committee: CARLOS MARQUARDT JORGE CREMPIEN SARA ELGUETA SERGIO SEPÚLVEDA LEONARDO VANZI Thesis submitted to the Office of Research and Graduate Studies in partial fulfillment of the requirements for the Degree of Master of Science in Engineering Santiago de Chile, (December, 2020) A María Ignacia y Emma, mis pequeñas sobrinas, cuyo futuro sea sustentable, resiliente y en igualdad ACKNOWLEDGEMENTS Quisiera agradecer a mis padres, Blanca y Carlos, por su apoyo constante e incondicional, sin ellos absolutamente nada de este trabajo sería posible. A mis abuelas, Emma y Herminda, a quienes admiro infinitamente, de ellas he aprendido y continúo aprendiendo. A mis hermanos Valeska y Carlos, y a sus respectivos compañeros de vida Roland y Carolina a quienes considero hermanos también, gracias por todos sus consejos y orientación a lo largo de mi camino universitario y del magíster. En especial quisiera agradecer a la Escuela de Ingeniería UC, donde conocí a grandes docentes que me confirmaron que la investigación y la docencia es mi camino por seguir. A Sara Elgueta, que por tantos años me transmitió su conocimiento, me permitió trabajar codo a codo y me brindó tantas oportunidades. A Carlos Marquardt que me acogió desde el primer día como su alumna, me permitió explorar y contribuir con ideas nuevas en este trabajo y me motivó constantemente. A Jorge Crempien, quien con paciencia y motivación me guio en gran parte de este trabajo. A Gonzalo Yáñez y Esteban Sáez, por permitirme ser parte del proyecto FONDEF +Andes 2.0, donde se gestó este trabajo. A José Cembrano, Gonzalo Yáñez y Gloria Arancibia por mostrarme lo bello de la geología y su apoyo constante durante el pregrado y postgrado. A Felipe, Javi y Ronny, por el apañe en terreno, a todo el grupo de Geociencias UC por el apañe en San Joaquín. A Rorro, gracias a este postgrado gané un gran amigo. A Laura, Cototo, Fran, Toti, por hacer siempre más ameno el trabajo diario en la salita de postgrado del DIM. A Claudio, Pato, Valeria, Marco y Daniel, por estar siempre dispuestos retroalimentar mis avances. A mis amigos de la vida Katherine y Chris, que me escucharon y soportaron mis locuras. A Lucho que apareció en la última etapa a apañar. A los funcionarios del DIM, quienes me acogieron desde el primer día, en especial a Cecilia Meza, quien siempre me orientó cuando lo necesité. Al DIEG, donde siempre estuvieron disponibles a ayudarme. A Danisa Herrera, quien siempre supo resolver mis dudas en la Dirección de Postgrado. A Andrew Hodgkin por ayudarme incondicionalmente en terreno, en gabinete y en la realización de esta tesis. A Kate Allstadt, Randy Jibson y Bill Murphy, que siempre estuvieron dispuestos a resolver mis dudas. A los profesores y asistentes de iRALL School 2019, que me brindaron la oportunidad de mirar de otra forma el estado del arte y me brindaron sugerencias que mejoraron mi trabajo. A los miembros de mi comisión, Leonardo Vanzi, Sergio Sepúlveda, Jorge Crempien, Carlos Marquardt y Sara Elgueta que me entregaron la retroalimentación y las sugerencias necesarias para mejorar aún más este trabajo. iii GENERAL INDEX Pág. DEDICATION........................................................................................................ iii ACKNOWLEDGEMENTS .................................................................................... iii INDEX OF TABLES ............................................................................................... vi INDEX OF FIGURES ............................................................................................vii ABSTRACT ............................................................................................................ ix 1 Introduction ................................................................................................... 10 1.1 Landslides caused by earthquakes: A brief review ................................. 11 1.2 Case Study: Coastal Range of Central Chile, Valparaíso Region, Chile .. 13 1.3 Research question and Hypothesis ......................................................... 13 1.4 Objectives.............................................................................................. 14 1.4.1 Main Objective ............................................................................ 14 1.4.2 Specific Objectives ...................................................................... 14 2 Geological Setting ......................................................................................... 15 2.1 Geomorphological Setting ..................................................................... 15 2.2 Stratigraphy ........................................................................................... 15 2.2.1 Paleozoic Units ...................................................................................... 16 2.2.2 Mesozoic Units ...................................................................................... 19 2.2.3 Cenozoic Units ...................................................................................... 20 2.3 Seismotectonic Setting ........................................................................... 25 3 Methodology ................................................................................................. 29 3.1 Conditioning factor of landslide hazard analysis .................................... 29 3.2 GIS based Spatial distribution analysis .................................................. 30 3.3 Broadband Synthetic Seismograms ........................................................ 33 3.4 Newmark Analysis ................................................................................ 35 4 Results: Paper submitted to Engineering geology ........................................... 38 iv 5 Discussion ..................................................................................................... 92 6 Conclussions .................................................................................................. 95 References .............................................................................................................. 96 Annex 106 v INDEX OF TABLES Pag. Table 1: Landslide Classification proposed by Hungr et al. (2013), after Varnes (1984) .................................................................................................................................... 11 Table 2: Hazard categorization based on dip and lithology of slope .............................. 29 Table 3: Values of input parameters of UCSB Broadband Synthetic seismograms........ 34 Table 4: Categorization of the hazard based on Newmark Displacement (Jibson and Michael, 2009) ............................................................................................................. 93 vi INDEX OF FIGURES Pag. Figure 1: Co-seismic Landslides and their subsequent hazards triggered by crustal earthquakes. (Modified from Fan et al., 2019) .............................................................. 12 Figure 2: Simplified Geological Map of Coastal Range of Valparaiso Region, Chile. Geological units of Paleozoic and Mesozoic ages are grouped by rock type. Sedimentary units of Neogene and Quaternary are shown in detail. Quaternary units from West to East are: Marine Terraces Deposits, Aeolian Deposits, Aeolian palaeodunes Deposits, Alluvial and Colluvial Deposits and Fluvial Deposits. ............................................................... 17 Figure 3: Block Diagram of Seismicity in Andean Subduction zone, between latitudes 30S and 35S. Historical megathrusts are shown with yellow lines of its rupture lengths in the area (Based on Ruiz & Madariaga (2018). Crustal seismicity is exhibited by the focal mechanisms of events between 1976 and 2018 (CMT Global Catalog, Ekström et al., 2012). The focal mechanisms in red corresponds to major events such as: Las Melosas Mw6.3 1958 (Sepúlveda et al, 2008), Mendoza 6.4Mw, Teno Mw6.5 2004, Pichilemu Mw7.0 and Mw6.9 2010 (CMT Global Catalog). Slab geometry based on SLAB1.0 USGS project. Internal structure of Lithosphere and Asthenosphere is based on thermal model of Valdenegro et al., (2019). Megathrusts faulting domains A, B C and D (Lay et al., 2012) are shown as yellow bold segments. ............................................................................. 27 Figure 4: Map of study sub-areas, where the Broadband synthetic seismograms and Newmark analysis where computed. The Marga-Marga and Aconcagua faults are shown. The hypothetic epicenters for strike-slip scenarios are shown as red stars. .................... 32 Figure 5: Newmark sliding block scheme. The problem is approximated by rigid sliding block with known cohesion, friction angle, bulk density, thickness, and saturated proportion. The component of acceleration-time history a(t) in dip and dip-direction is used in 1-D Newmark
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