Papers by Cristian Araya-Cornejo
Estudios Socioterritoriales. Revista de Geografía
Los Desastres Socionaturales son una realidad con que ha convivido el ser humano desde que tiene ... more Los Desastres Socionaturales son una realidad con que ha convivido el ser humano desde que tiene memoria. A pesar de los esfuerzos realizados para erradicarlos en Chile y el mundo, aún existen un sinnúmero de falencias técnicas, normativas, institucionales y éticas, que han hecho que persista un problema que muchos creyeron poder erradicar con los avances de la ciencia moderna y una gruesa institucionalidad, tanto nacional como internacional, reflejando un remanente utilitarista. El claro vacío ético en la discusión ha llevado a que, desde la academia y desde disciplinas como la Geografía se hayan realizado aportes que han superado la barrera técnico-científica, incluyendo conceptos provenientes del enfoque occidental rawlsiano de la justicia social. Si bien es un avance importante, debido a que es un problema global, se debe avanzar hacia una discusión que incluya todas las visiones y todos los componentes del problema, es decir, a la Tierra y su comunidad biótica. Este trabajo pro...
Bookmarks Related papers MentionsView impact
EGU General Assembly Conference Abstracts, Apr 1, 2017
Bookmarks Related papers MentionsView impact
AGU Fall Meeting Abstracts, Dec 1, 2020
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
We present evidence that suggests a new risk scenario for the Valdivia basin in south Chile, loca... more We present evidence that suggests a new risk scenario for the Valdivia basin in south Chile, located in the area of the magnitude 9.5 1960 earthquake. In 1960, three mass movements, triggered by the earthquake shaking, dammed the upper course of the San Pedro River and threatened Valdivia City until it was opened in a controlled manner by its inhabitants. Published historical accounts indicate that the 1575 earthquake, predecessor of the 1960 event, also triggered a mass movement that dammed the upper course of the river. However, here we reinterpret the published account and present new historical records, which we combined with satellite imagery and field surveys to show that the volume of the landslide in 1575 was smaller than the smallest of those of 1960, yet its outburst flood killed thousands of natives located downstream. Additionally, we characterized different mass movement deposits in the upper course of the San Pedro River, including both ancient and those formed in 1960...
Bookmarks Related papers MentionsView impact
Investigaciones Geográficas, 2016
Bookmarks Related papers MentionsView impact
cybertesis.uchile.cl
... gracias por todo. A los amigos y compañeros: Cecilia Aqueveque, Orlando Arévalo, Alberto Iria... more ... gracias por todo. A los amigos y compañeros: Cecilia Aqueveque, Orlando Arévalo, Alberto Iriarte, Pablo Iribarren, Alejandro Ortega, Marcela Rodríguez y Juan Pablo Valenzuela. Gracias por su apoyo y compañía. A todos ...
Bookmarks Related papers MentionsView impact
Natural hazards, Mar 10, 2024
Damming rivers by landslides and ensuing outburst flooding is a common and potentially hazardous ... more Damming rivers by landslides and ensuing outburst flooding is a common and potentially hazardous phenomenon worldwide, especially in tectonically active regions. Remarkable examples are the damming of the upper course of the San Pedro River (SPR) in south Chile during the 1960 Chile earthquake (M9.5) and its predecessor in 1575. Outburst floods following both events had tragic consequences for downstream communities. Here, we study both events from multiple sources of information, including previously published and newly found historical records, satellite imagery, LiDAR topography, and sedimentological and geomorphological field observations. We present the first detailed geomorphic map of the region. Morphological similarities between ancient deposits at the SPR and those associated with the 1960 earthquake suggest that the SPR has been dammed repeatedly in the past. The steep incision of the SPR and the sediments of glacio-lacustrine origin in the surrounding slopes facilitate the initiation of large landslides. The knowledge gained from studying these past events provides important implications for future risk assessments. We propose that besides large earthquakes, smaller and more frequent earthquakes as well as changes in land use, can also result in river-damming events.
Bookmarks Related papers MentionsView impact
Natural Hazards, 2024
Damming rivers by landslides and ensuing outburst flooding is a common and potentially hazardous ... more Damming rivers by landslides and ensuing outburst flooding is a common and potentially hazardous phenomenon worldwide, especially in tectonically active regions. Remarkable examples are the damming of the upper course of the San Pedro River (SPR) in south Chile during the 1960 Chile earthquake (M9.5) and its predecessor in 1575. Outburst floods following both events had tragic consequences for downstream communities. Here, we study both events from multiple sources of information, including previously published and newly found historical records, satellite imagery, LiDAR topography, and sedimentological and geomorphological field observations. We present the first detailed geomorphic map of the region. Morphological similarities between ancient deposits at the SPR and those associated with the 1960 earthquake suggest that the SPR has been dammed repeatedly in the past. The steep incision of the SPR and the sediments of glacio-lacustrine origin in the surrounding slopes facilitate the initiation of large landslides. The knowledge gained from studying these past events provides important implications for future risk assessments. We propose that besides large earthquakes, smaller and more frequent earthquakes as well as changes in land use, can also result in river-damming events.
Bookmarks Related papers MentionsView impact
This paper presents the geomorphological evolution of larger slide generated by the 1960 earthqua... more This paper presents the geomorphological evolution of larger slide generated by the 1960 earthquake, which dammed the San Pedro River, which was known locally as "Taco" 3. First, a geological and geomorphological characterization of the slide was made for years 1960 and 2010. After a comparative analysis between two topographic profiles obtained of Davis and Karzúlovic (1961), and two profiles derived from altimetry detail information from a survey conducted with LIDAR technology by 2010. It is further proposed by applying a diffusion equation, a representative rate of erosion for the Upper San Pedro River over the last 50 years. The results of this work together with the analysis of other historical evidence of landslides triggered by earthquakes, such as occurred in 1575, represent a valuable information for future of a paleosismolgical research of the Upper San Pedro River.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
Geophysical Research Letters, 2019
Bookmarks Related papers MentionsView impact
The relationships between beach ridge plain and superimposed coastal dunes are studied in La Trin... more The relationships between beach ridge plain and superimposed coastal dunes are studied in La Trinchera erg, Maule region, by means of surface geomorphology, drilling and sedimentary analysis. The underlying strand plain is composed by a set of multiple beach ridges, which represents a prograded shore plain. The superimposed dunes have been formed in three different pulses: old, middle and modern. The allostratigraphy and regional correlations support the model of alternate sediment decoupling for the formation of the old dune system and the model of sequential sediment sourcing for the construction of the middle and modern pulses.
Bookmarks Related papers MentionsView impact
Bookmarks Related papers MentionsView impact
El terremoto gigante de 1960, con una ruptura de 1000 km de largo entre las placas de Nazca y Sud... more El terremoto gigante de 1960, con una ruptura de 1000 km de largo entre las placas de Nazca y Sudamericana, produjo tres deslizamientos que represaron por dos meses el cauce del río San Pedro cerca de la desembocadura del lago Riñihue (llamados “tacos” 1, 2 y 3). El represamiento significó una seria amenaza para los asentamientos humanos localizados aguas abajo, incluyendo la ciudad de Valdivia. Afortunadamente, el desastre se evitó gracias a la apertura controlada del cauce. Existen evidencias históricas de la ocurrencia de un proceso similar gatillado por el terremoto de 1575 en el mismo sector. Sin embargo, en esa ocasión la represa acumuló agua durante cinco meses, colapsando catastróficamente y cobrando la vida de miles de indígenas. Trabajos previos han localizado, sobre la base de evidencia geomorfológica, las huellas de dicho deslizamiento. Se trata de un gigantesco escarpe con depósitos de deslizamientos, de 2.6 km de largo, emplazado en la ribera sur del río. En el present...
Bookmarks Related papers MentionsView impact
Geology, 2019
Bookmarks Related papers MentionsView impact
Geology, 2019
Subduction zone seismicity arises from megathrust, crustal, and intraslab earthquakes, and unders... more Subduction zone seismicity arises from megathrust, crustal, and intraslab earthquakes, and understanding the recurrence patterns of each type is crucial for hazard assessments. Lake sediments can record earthquakes from all three seismogenic sources. Here, we studied the turbidite record of Lo Encañado, an Andean lake located in central Chile. We show that Lo Encañado turbidites can be attributed to (1) subaquatic slope failure by earthquake shaking (coseismic phase), (2) floods or human impact, and (3) postseismic catchment response. All historical events with shaking intensities >VI (modified Mercalli intensity) have triggered coseismic turbidites, but only the intraplate earthquakes triggered subaerial slope failures followed by postseismic turbidites. We argue that this contrasting result is due to different spectra of seismic waves from these earthquake sources: higher-frequency accelerations from intraplate earthquakes are hardly attenuated in rocks around the lake, whereas lowerfrequency accelerations from megathrust earthquakes are amplified in soft lake sediments. We tested our findings by comparing acceleration response spectra of recent and historical intraslab and megathrust earthquakes along a longitudinal profile. Results suggest that the location of Andean lakes is ideal to distinguish earthquake sources.
Bookmarks Related papers MentionsView impact
Geophysical Research Letters, 2019
The tsunami observations produced by the 2018 magnitude 7.5 Palu strike‐slip earthquake challenge... more The tsunami observations produced by the 2018 magnitude 7.5 Palu strike‐slip earthquake challenged the traditional basis underlying tsunami hazard assessments and early warning systems. We analyzed an extraordinary collection of 38 amateur and Closed Circuit Television videos to show that the Palu tsunami devastated widely separated coastal areas around Palu Bay within a few minutes after the mainshock and included wave periods shorter than 100 seconds missed by the local tide station. Although rupture models based on teleseismic and geodetic data predict up to 5‐m tsunamis, they cannot explain the higher surveyed runups nor the tsunami waveforms reconstructed from video footage, suggesting either these underestimate actual seafloor deformation and/or that non‐tectonic sources were involved. Post‐tsunami coastline surveys combined with video evidence and modeled tsunami travel times suggest that submarine landslides contributed to tsunami generation. The video‐based observations have broad implications for tsunami hazard assessments, early warning systems and risk‐reduction planning
Bookmarks Related papers MentionsView impact
The analysis of satellite images together with field observations, allowed the identification and... more The analysis of satellite images together with field observations, allowed the identification and description of the geomorphological consequences of the Chilean tsunami of 2010 in La Trinchera. La Trinchera is a sandy coastline located in front of the area of the earthquake's maximum slip. The tsunami opened breaches and built fans in beach ridges and dunes; eroded vegetated dunes and formed pedestals; produced a retreat of the coastline of hundreds of meters; formed flood scours up to 350 m long in the southern bank of the Mataquito and Huenchullami rivers; and almost entirely eroded the sand spits of the Mataquito River estuary and part of the sand bar of Huenchullami river. Both the direct effects of the tsunami and the scope of the inundation were controlled by the dominant type of dune which corresponds to barchans and parabolic dunes. Since the tsunami several processes have been observed, such as proliferation of sand sheets, transformations in the morphology of dunes and rapid recovery of the sand spits of the Mataquito River estuary. All of these processes suggest an alteration in the exchange of sediment in the beach-dune system.
Bookmarks Related papers MentionsView impact
Uploads
Papers by Cristian Araya-Cornejo