Earthquake Of February Research Articles

On the magnetic precursor of the Chilean earthquake of February 27, 2010

Some recent publications reported on an anomalous geomagnetic disturbance that was observed three days before the strongest Chilean earthquake on February 27, 2010. The present paper analyzes in detail the data from magnetic station, photometers, and riometers in Canada, Chile, and Antarctica. The analysis unambiguously shows that the supposedly anomalous geomagnetic disturbance was not related to seismic activity and was caused by a standard isolated substorm.

The February 2014 Cephalonia Earthquake (Greece): 3D Deformation Field and Source Modeling from Multiple SAR Techniques

Online Material: Tables of moment tensor elements; SAR image pairs and coseismic displacement gradients; figures of InSAR data, model parameter tradeoffs, and observed and modeled displacements. On 26 January 2014 at 13:55 UTC, an M w 6.0 earthquake struck the island of Cephalonia, Greece, followed five hours later by an M w 5.3 aftershock and by an M w 5.9 event on 3 February 2014 at 03:08 UTC (National Observatory of Athens, Institute of Geodynamics [NOA‐GI]). The epicenter of the M w 6.0 event was relocated 2 km east of the town of Lixouri, and that of the M w 5.9 event at the tip of the Gulf of Argostoli, in the northern part of the Paliki peninsula (Fig. 1; Karastathis et al. , 2014; Papadopoulos et al. , 2014). Extensive structural damage and widespread environmental effects were induced throughout the Paliki peninsula and along the eastern coast of the Gulf of Argostoli (Valkaniotis et al. , 2014). Quays, sidewalks, and piers were damaged in the waterfront areas of the towns of Lixouri and Argostoli, the island capital, and liquefactions, road failures, rock falls, and small landslides were observed. Most of the latter effects took place in the aftermath of the 26 January 2014 event and were reactivated one week later by the 3 February earthquake. Figure 1. Location map showing the tectonic context of the Aegean Sea and the main faults on the island of Cephalonia. Colored rectangles and magenta triangles indicate the Synthetic Aperture Radar (SAR) frame coverage and the continuous Global Positioning System (cGPS) stations, respectively. Yellow stars indicate the relocated epicenters of the three largest events of the 2014 sequence (Karastathis et al. , 2014). Diverging and converging arrows in the top‐right map indicate approximate horizontal projections of the P axis (compression) and T axis (extension), respectively, based on figure 5b in …

“Great East Siberian” earthquake of February 1, 1725 (M = 8.2): Revision of the main parameters in the light of additional data and modern requirements

The earthquake of February 1 (January 21 in the Julian Calendar), 1725 was for a long time considered not only the earliest precisely dated historical seismic event in eastern Siberia, but also the most powerful earthquake for the entire period of recorded seismic events in the region: M = 8.2 (Novyi katalog…, 1977). The epicenter location (Stanovoy Upland) and the magnitude of the event were assessed on the basis of very scanty historical data, as well as using paleoseismogeological information. The February 1, 1725 event received the name “The Great East Siberian” earthquake and served for decades as decisive evidence for the assessment of the seismic hazard and seismic zoning of the northeastern flank of the Baikal rift zone. However, the solution of the focal parameters in the (Novyi katalog…, 1977) has caused serious doubts. In this paper a newly elaborated version is proposed that is based on a detailed reevaluation of the initially known macroseismic information, as well as additional historical data that previously had not come to the attention of seismologists. As the result, a different solution of the focal parameters (51.8° N; 113.0° E, eastern Transbaikalia) and a significantly lower magnitude (M = 6.0) compared with the parameters given in (Novyi katalog…, 1977) were obtained. The presented solution makes us more attentive to the estimates of seismic hazard in east Transbaikalia based on historical data, as well as to the historical data themselves.

Inelastic Dynamic and Non-Linear Static Seismic Performance of a Building with RC Walls that Collapsed in the Chile’s Earthquake of February 2010 and a Building with RC Concrete Frame Designed in the Mexico City

The objectives in this paper are the followings: evaluate the seismic performance of the three buildings and compare the elastic and inelastic seismic responses of the buildings, calculated with the records CCH-NS (Chilean earthquake 2010) and SCT-EW (Mexican earthquake 1985) of the cases of strengths elastic and inelastic with nominal strength and over-strength of each model. The building 1 is a real case of a concrete wall building that collapsed during the Chilean earthquake of February 27, 2010. The building 2 was analyzed and designed with the Chilean Norm “Seismic Design of Buildings” (NCH-433) and “Reinforced Concrete–Design and Calculus Requirements” (NCH-430). The analyses and design of the building 3 was realized with the Mexican Norms “Complementary Technical Norms for seismic design” (NTC-Seismic), “Complementary Technical Norms for Design and Construction of Concrete Structures” (NTC-Concrete) of the “Code of Constructions for the Federal District” (RCDF-04). The elastic and inelastic seismic responses of each building were calculated with the step by step dynamic method. Should be avoided that the fundamental period of vibration of the structures match with the dominant period of the ground (Ts). In the design of concrete structural walls is very important classified the walls according to its slenderness in order to recognize the behavior that will govern the wall, and with it determine the detailed of the steel reinforcement that could provide the best behavior when the wall be submitted to an important earthquake.

Outbreak of Paecilomyces variotii Peritonitis in Peritoneal Dialysis Patients after the 2010 Chilean Earthquake

Fungal peritonitis (FP) accounts for 3 - 6% of all peritonitis episodes in chronic peritoneal dialysis (PD), being associated with high morbidity and mortality. Mortality rates are in the range of 15 - 50%, and loss of the peritoneal membrane function can be over 40% (1). The most common cause of the disease is Candida species (C. albicans, C. parapsilosis, C. glabrata). Other yeasts and filamentous fungi such as Aspergillus, Paecilomyces, Penicillium, and Zygomycetes are found less frequently. The strongest risk factors for FP in PD patients are prolonged use of antibiotics and previous bacterial peritonitis (2). Other suggested risk factors are immunosuppression, malnutrition, bowel perforation, diverticulitis, and, possibly, certain comorbidities such as diabetes or neoplastic diseases (1). Paecilomyces spp is a filamentous fungus like the genus Penicillium and Aspergillus. It is found in soil and water and is one of the main dwellers of house dust. It is rarely associated with human infections. When a disease does occur, it is more often related to foreign bodies or immunosuppressed patients (3,4). After the earthquake of February 27, 2010, in Chile, there was an increase in the rate of FP from 1% to 6%, due to the appearance of 6 cases caused by Paecilomyces variotti (5). Here we describe the clinical characteristics and outcomes of 3 of these patients. Although there was no proof of the precise route of infection in our patients, in all 3 cases there was a major alteration in the storage of the PD fluid bags, resulting especially in exposure to excessive dust and destruction of the architecture of the storage holds. It is quite possible that in the context of a natural disaster like a big earthquake, the risk of infections associated with this fungus could increase because of the excessive dust in the environment.

Seismic Performance of a Six-Story Reinforced Concrete Masonry Building during the Canterbury Earthquake Sequence

During the Christchurch earthquake of February 2011, several midrise reinforced concrete masonry (RCM) buildings showed performance levels that fall in the range of life safety to near collapse. A case study of one of these buildings, a six-story RCM building deemed to have reached the near collapse performance level, is presented in this paper. The RCM walls on the second floor failed due to toe crushing, reducing the building's lateral resistance in the east–west direction. A three-dimensional (3-D) nonlinear dynamic analysis was conducted to simulate the development of the governing failure mechanism. Analysis results showed that the walls that were damaged were subjected to large compression loads during the earthquake, which caused an increase in their in-plane lateral strength but reduced their ductility capacity. After toe crushing failure, axial instability of the model was prevented by a redistribution of gravity loads.

El terremoto chileno del 27 de febrero de 2010: análisis preliminar de las consecuencias en la ciudad de Valdivia

El mayor sismo que haya afectado a la ciudad de Valdivia con posterioridad al famoso terremoto de 1960 fue el generado por el evento (Mw 8,8) del 27 de febrero de 2010 en la zona central de Chile. La intensidad asignada para la ciudad de Valdivia alcanzó el valor VI en la escala de Mercalli. Con el objeto de comprender la distribución espacial de los daños a la infraestructura urbana, se relacionó ésta con las condiciones locales de suelo. Los antecedentes de la historia sísmica y del desarrollo urbano de Valdivia proporcionan información valiosa que se agregó al análisis. La diferente severidad con la que el sismo repercutió en los diversos barrios de Valdivia, guarda una estrecha relación con las unidades geomorfológicas y los tipos de suelos de fundación existentes en la ciudad. Se pudo establecer una buena coincidencia con la respuesta sísmica de los suelos prevista para la ciudad en estudios previos.

The Christchurch earthquake stroke incidence study

We examined the impact of major earthquakes on acute stroke admissions by a retrospective review of stroke admissions in the 6weeks following the 4 September 2010 and 22 February 2011 earthquakes. The control period was the corresponding 6weeks in the previous year. In the 6weeks following the September 2010 earthquake there were 97 acute stroke admissions, with 79 (81.4%) ischaemic infarctions. This was similar to the 2009 control period which had 104 acute stroke admissions, of whom 80 (76.9%) had ischaemic infarction. In the 6weeks following the February 2011 earthquake, there were 71 stroke admissions, and 61 (79.2%) were ischaemic infarction. This was less than the 96 strokes (72 [75%] ischaemic infarction) in the corresponding control period. None of the comparisons were statistically significant. There was also no difference in the rate of cardioembolic infarction from atrial fibrillation between the study periods. Patients admitted during the February 2011 earthquake period were less likely to be discharged directly home when compared to the control period (31.2% versus 46.9%, p=0.036). There was no observable trend in the number of weekly stroke admissions between the 2weeks leading to and 6weeks following the earthquakes. Our results suggest that severe psychological stress from earthquakes did not influence the subsequent short term risk of acute stroke, but the severity of the earthquake in February 2011 and associated civil structural damages may have influenced the pattern of discharge for stroke patients.

Recovering from the earthquake

Purpose – Traumatic events can cause post-traumatic stress disorder due to the severity of the often unexpected events. The purpose of this paper is to reveal how conversations around lived experiences of traumatic events, such as the Christchurch earthquake in February 2011, can work as a strategy for people to come to terms with their experiences collaboratively. By encouraging young children to recall and tell of their earthquake stories with their early childhood teachers they can begin to respond, renew, and recover (Brown, 2012), and prevent or minimise more stress being developed. Design/methodology/approach – The study involved collecting data of the participating children taking turns to wear a wireless microphone where their interactions with each other and with teachers were video recorded over one week in November 2011. A total of eight hours and 21 minutes of footage was collected; four minutes and 19 seconds of that footage are presented and analysed in this paper. The footage was watched repeatedly and transcribed using conversation analysis methods (Sacks, 1995). Findings – Through analysing the detailed turn-taking utterances between teachers and children, the orderliness of the co-production of remembering is revealed to demonstrate that each member orients to being in agreement about what actually happened. These episodes of story telling between the teachers and children demonstrate how the teachers encourage the children to tell about their experiences through actively engaging in conversations with them about the earthquake. Originality/value – The conversation analysis approach used in this research was found to be useful in investigating aspects of disasters that the participants themselves remember as important and real. This approach offers a unique insight into understanding how the earthquake event was experienced and reflected on by young children and their teachers, and so can inform future policy and provision in post-disaster situations.

Innovations and lessons learned from the Canterbury earthquakes

Purpose– The purpose of this paper is to identify innovations and lessons learned from interviews with members of the multidisciplinary healthcare team who participated in the response to the 22 February earthquake, affecting the Canterbury region of New Zealand's South Island.Design/methodology/approach– Narratives from individual staff members who were associated with the Christchurch Hospital Emergency Department response were recorded and analysed. This data, together with other contextual documents have been used to identify the responses of healthcare workers to an unexpected natural disaster. Perspectives were sought from a range of individuals, including allied health professionals, social workers, Maori health workers, orderlies, medical and nursing staff.Findings– The individual as well as the organisational responses to the earthquake events are significant, and need to be considered in relation to future planning and responses. In particular, the importance of encouraging and supporting a culture which values innovation and responsiveness was identified. While specific, practical responses to the earthquake disaster are noted, it is also important to acknowledge the implication for individuals of an acute, unanticipated event.Research limitations/implications– The findings from this study have the potential to illuminate possible responses in other crisis situations, and to guide the development of targeted support measures in response to disaster events.Originality/value– Little documentation has occurred to date relating the experiences of health care responders who are not only reacting to a natural disaster, but are also part of it. This is a unique and valuable perspective that has relevance within a number of settings.

Acute Myocardial Infarction and Stress Cardiomyopathy following the Christchurch Earthquakes

BackgroundChristchurch, New Zealand, was struck by 2 major earthquakes at 4:36am on 4 September 2010, magnitude 7.1 and at 12:51pm on 22 February 2011, magnitude 6.3. Both events caused widespread destruction. Christchurch Hospital was the region's only acute care hospital. It remained functional following both earthquakes. We were able to examine the effects of the 2 earthquakes on acute cardiac presentations.MethodsPatients admitted under Cardiology in Christchurch Hospital 3 week prior to and 5 weeks following both earthquakes were analysed, with corresponding control periods in September 2009 and February 2010. Patients were categorised based on diagnosis: ST elevation myocardial infarction, Non ST elevation myocardial infarction, stress cardiomyopathy, unstable angina, stable angina, non cardiac chest pain, arrhythmia and others.ResultsThere was a significant increase in overall admissions (p<0.003), ST elevation myocardial infarction (p<0.016), and non cardiac chest pain (p<0.022) in the first 2 weeks following the early morning September earthquake. This pattern was not seen after the early afternoon February earthquake. Instead, there was a very large number of stress cardiomyopathy admissions with 21 cases (95% CI 2.6–6.4) in 4 days. There had been 6 stress cardiomyopathy cases after the first earthquake (95% CI 0.44–2.62). Statistical analysis showed this to be a significant difference between the earthquakes (p<0.05).ConclusionThe early morning September earthquake triggered a large increase in ST elevation myocardial infarction and a few stress cardiomyopathy cases. The early afternoon February earthquake caused significantly more stress cardiomyopathy. Two major earthquakes occurring at different times of day differed in their effect on acute cardiac events.

Ecologically Sustainable Water Management:Role Of The Academy To Face The Development?Pressures And Challenges – Experiences In Chile

The experience of the earthquake and tsunami of February 27, 2010 revealed a variety of shortcomings in ensuring the safety of the population, urban centers, coastal areas and land-use situations, which resulted in the loss of many lives and extensive damage to urban infrastructure and economic productivity, with signifi cant social impact. Because of its complex geography and the permanent risk of natural disasters (earthquakes, tsunamis, volcanic eruptions, and torrential river fl oods), as well vulnerability to climate change, Chile represents important academic challenges to defi ne research programs to provide preventive and mitigating actions to address this reality. It must be added that interventions with large-scale projects (hydropower, irrigation channels, civil works in areas with river fl ooding and along the coastline) as well as the intensive exploitation of natural resources (water, soil and vegetation) combine to form a complex environmental situations that is diffi cult to understand and manage. In response to this situation, the University of Concepcion through its Research Offi ce created the Reconstruction Program, composed of working groups in various fi elds to analyze the consequences of the seismic event and tsunami and develop proposals to address the reconstruction measures for the region, as well as to develop new approaches and tools to face this reality. From the academic point of view, this represents opportunities for international collaboration, both for scientifi c research and post-graduate studies.

The aftershock process of the February 21, 2008 Storfjorden Strait, Spitsbergen, earthquake

This study is concerned with the aftershock process of the Mw 6.1 Storfjorden Strait, Spitsbergen earthquake of February 21, 2008, which was the largest to have occurred in the West Arctic shelf during the entire history of instrumental observation. The aftershock sequence was fitted by relaxation models and the ETAS model and was found to be a combination of two processes, a relaxation process and a triggered one. We propose a hypothesis about the relationship between seismicity and disturbances of fluid dynamic equilibrium in the seafloor of the Storfjord Strait.

Impact of the Christchurch Earthquakes on Hospital Staff

On September 4, 2010 a major earthquake caused widespread damage, but no loss of life, to Christchurch city and surrounding areas. There were numerous aftershocks, including on February 22, 2011 which, in contrast, caused substantial loss of life and major damage to the city. The research aim was to assess how these two earthquakes affected the staff in the General Medicine Department at Christchurch Hospital. Problem To date there have been no published data assessing the impact of this type of natural disaster on hospital staff in Australasia. A questionnaire that examined seven domains (demographics, personal impact, psychological impact, emotional impact, impact on care for patients, work impact, and coping strategies) was handed out to General Medicine staff and students nine days after the September 2010 earthquake and 14 days after the February 2011 earthquake. Response rates were ≥ 99%. Sixty percent of responders were <30 years of age, and approximately 60% were female. Families of eight percent and 35% had to move to another place due to the September and February earthquakes, respectively. A fifth to a third of people had to find an alternative route of transport to get to work but only eight percent to 18% took time off work. Financial impact was more severe following the February earthquake, with 46% reporting damage of >NZ $1,000, compared with 15% following the September earthquake (P < .001). Significantly more people felt upset about the situation following the February earthquake than the September earthquake (42% vs 69%, P < .001). Almost a quarter thought that quality of patient care was affected in some way following the September earthquake but this rose to 53% after the February earthquake (12/53 vs 45/85, P < .001). Half believed that discharges were delayed following the September earthquake but this dropped significantly to 15% following the February earthquake (27/53 vs 13/62, P < .001). This survey provides a measure of the result of two major but contrasting Christchurch earthquakes upon General Medicine hospital staff. The effect was widespread with minor financial impact during the first but much more during the second earthquake. Moderate psychological impact was experienced in both earthquakes. This data may be useful to help prepare plans for future natural disasters. .

Neutron generation and geomagnetic disturbances in connection with the Chilean earthquake of February 27, 2010 and a volcanic eruption in Iceland in March–April 2010

The relationship between solar and geomagnetic activities in connection with seismicity and vol� canic eruptions on the globe during the period 1680-2010 is studied. The centennial cycles of terrestrial endogenous activity, related to solar and geomagnetic activity, are revealed; at the beginning of these cycles, solar cycles with small Wolf numbers were detected, while intensive seismic and volcanic activity was observed for several decades. A stable negative correlation between seismicity and volcanism, on the one hand, and solar and geomagnetic activity, on the other hand, were found. Experiments, which were simultaneously car� ried out at the Pushkov Institute of Geomagnetism, Ionosphere, and Radiowave Propagation, Russian Acad� emy of Sciences (IZMIRAN), Troitsk, Moscow oblast, and the Karymshina Complex Geophysical Observa� tory, Kamchatka Branch, Geophysical Survey, Russian Academy of Sciences, have verified the suggestion that disturbances in the geomagnetic field and neutron generation occur during the early stages of strong earthquakes. It is supposed that the mechanism of primary generation of terrestrial neutrons is related to nuclear reactions in the Earth's interior.

Lake sediments as natural seismographs: A compiled record of Late Quaternary earthquakes in Central Switzerland and its implication for Alpine deformation

AbstractCentral Switzerland lies tectonically in an intraplate area and recurrence rates of strong earthquakes exceed the time span covered by historic chronicles. However, many lakes are present in the area that act as natural seismographs: their continuous, datable and high‐resolution sediment succession allows extension of the earthquake catalogue to pre‐historic times. This study reviews and compiles available data sets and results from more than 10 years of lacustrine palaeoseismological research in lakes of northern and Central Switzerland. The concept of using lacustrine mass‐movement event stratigraphy to identify palaeo‐earthquakes is showcased by presenting new data and results from Lake Zurich. The Late Glacial to Holocene mass‐movement units in this lake document a complex history of varying tectonic and environmental impacts. Results include sedimentary evidence of three major and three minor, simultaneously triggered basin‐wide lateral slope failure events interpreted as the fingerprints of palaeoseismic activity. A refined earthquake catalogue, which includes results from previous lake studies, reveals a non‐uniform temporal distribution of earthquakes in northern and Central Switzerland. A higher frequency of earthquakes in the Late Glacial and Late Holocene period documents two different phases of neotectonic activity; they are interpreted to be related to isostatic post‐glacial rebound and relatively recent (re‐)activation of seismogenic zones, respectively. Magnitudes and epicentre reconstructions for the largest identified earthquakes provide evidence for two possible earthquake sources: (i) a source area in the region of the Alpine or Sub‐Alpine Front due to release of accumulated north‐west/south‐east compressional stress related to an active basal thrust beneath the Aar massif; and (ii) a source area beneath the Alpine foreland due to reactivation of deep‐seated strike‐slip faults. Such activity has been repeatedly observed instrumentally, for example, during the most recent magnitude 4·2 and 3·5 earthquakes of February 2012, near Zug. The combined lacustrine record from northern and Central Switzerland indicates that at least one of these potential sources has been capable of producing magnitude 6·2 to 6·7 events in the past.

Paleoseismic analysis of the San Vicente segment of the El Salvador Fault Zone, El Salvador, Central America

The El Salvador earthquake of February 13th 2001 (Mw 6.6) was associated with the tectonic rupture of the El Salvador Fault Zone. Paleoseismic studies of the El Salvador Fault Zone undertaken after this earthquake provide a basis for examining the longer history of surface rupturing earthquakes on the fault. Trenching at five sites along the San Vicente segment, a 21km-long and up to 2km-wide central section of the El Salvador Fault Zone, shows that surface fault rupture has occurred at least seven times during the past 8ka. Single-event displacements identified at each trench vary from several decimetres to at least 3.7m. Fault trace mapping, geomorphic analysis, and paleoseismic studies indicate a maximum magnitude for the El Salvador Fault Zone is c. Mw 7.6, with a recurrence interval of around 800yr. Earthquakes of Mw 6.6 or smaller, such as the February 2001 event are unlikely to be identified in the paleoseismic trenches, so our observations represent the minimum number of moderate to large earthquakes that have occurred on this part of the El Salvador Fault Zone. We observe significant variability in single-event displacement in the trenches, which we interpret as possible cascade rupture of several segments of the El Salvador Fault Zone. Combining displacements of river courses and the timing of events revealed in the trenches, we calculate a slip rate of c. 4mm/yr for El Salvador Fault Zone, identifying the fault zone as a major tectonic feature of the region, and a major source of seismic hazard and risk in El Salvador.

The Maule (Chile) earthquake of February 27, 2010: Development of hazard, site specific ground motions and back-analysis of structures

The Maule (Chile) earthquake of 27 February, 2010 has caused severe disruption and economic losses. With a magnitude of 8.8, it has been recorded as one of the largest earthquakes of the last century. The ground motion records from large subduction earthquakes, such as the Chile earthquake, are sparse. The number of accelerograms that recorded the strong ground motion was relatively few and only a few of these ground motions were released to engineering community. One of the objectives of this paper is to develop site specific ground motions that take into account the particular characteristics of this major earthquake. These are proposed to the engineering community as representative ground motions based on the best available data. The second objective of the paper is to investigate, using numerical tools, some typical failures observed in the engineered buildings and bridges. Although, in general engineered structures performed very well and the majority of failures, hence losses, were to non-engineered structures, some repeated deficiencies in structural design were observed. The developed hazard and site specific ground motions are used as inputs for inelastic dynamic analysis of advanced finite element building and bridge models. The results are processed to explain quantitatively the structural deficiencies observed in the field.

Historic and Traditional Structures during the 2010 Chile Earthquake: Observations, Codes, and Conservation Strategies

The Maule, Chile, earthquake of February 2010 affected the Central Valley stretching from north of Santiago to the Rio Bío-Bío in the south. The architectural heritage suffered considerable losses, with some buildings seriously damaged or partially collapsed even in Santiago and Valparaíso, areas less affected by the earthquake. Exposing the vulnerability of Chilean architectural heritage, this event has renewed the debate about the national attitude towards architectural preservation and conservation engineering. From the survey conducted by the authors, it emerged that many retrofit and repair techniques implemented following prior earthquakes in Chile resulted in ineffective performance in the February 2010 earthquake. Safety and preservation requirements that are regulated in countries with similar historic heritage are presented as viable alternatives to past approaches and are compared with the Chilean pre-code for earthen buildings, currently under development, which appears to embrace modern preservation philosophies. Suitable remedial strategies conclude the paper.

The Evolution of the Bío Bío Delta and the Coastal Plains of the Arauco Gulf, Bío Bío Region: the Holocene Sea-Level Curve of Chile*

ISLA, F. I.; QUEZADA, J. F.; MARTÍNEZ, C.; FERNÁNDEZ, A.; and JAQUE, E. 2012. The evolution of the Bío Bío delta and the coastal plains of the Arauco Gulf, Bío Bío region: The Holocene sea-level curve of Chile.Mid-Holocene highstands are characteristic of the Southern Hemisphere. The Chilean coast extends from 17°S to 56°S in a dominant microtidal regime; thus, it is an ideal place to test ages and altitudes of this highstand with minimal errors. However, coseismic events, the dynamic phenomena they triggered (tsunamis), and the behaviour of land in relation to the overriding of the South American Plate over the oceanic Nazca Plate, make it necessary to distinguish these effects from purely eustatic changes. To the south, the glacioisostatic uplift has been approximately measured. At 37°S, the Coronel coastal plain extends several kilometres inland. Its sediment availability has been related to the supplies of the Bío Bío River. From this beach-ridge plain, shell remains gave a radiocarbon age of 4370 ± 90 years before present (YBP), indicating a highstand not higher than 5 m. Further south, at the Carampangue coastal plain, southern coast of the Arauco Gulf, a radiocarbon age of 8010 ± 90 YBP marks the oldest age of this transgression. Some consequences of the earthquake and tsunami of February 27, 2010, are reported here. The radiocarbon ages of these plains permit completion of a Holocene sea-level curve. These Holocene sea-level data were compared to other regions of South America.