Earthquakes and landslides

Alluvial fans cut by tectonic faults can also yield information on the frequency of earthquakes. An offset debris flow fan in Owens Valley (California) was dated with °Be by Bierman et al. (1995). Based on boulder ages from different parts of the flow and the record of three faulting events, the authors deduced earthquake recurrence intervals of 5800-8000 years for that location. Zreda and Noller (1998) measured C1 in a bedrock fault scarp at Hebgen Lake (Montana) and were able to extract the ages of six prehistoric 

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A specialty of geology concerned with earth processes, earth resources, and engineering properties of earth materials and relevant to (1) the protection of human health and natural ecosystems from adverse biochemical and/or geochemical reactions to naturally occurring chemicals or to chemical compounds released into the environment by human activities and (2) the protection of life, safety, and well-being of humans from natural processes, such as floods, hurricanes, earthquakes and landslides, through land-use planning. 

Extreme poverty is the daily reality of very many of the world s people Even without the effects of hurricanes, floods, earthquakes and landslides, the immediate prospects for both the urban and rural poor in many parts of the world are bleak, with little or no access to even the most basic of infrastructure, education and healthcare, and with little, or at best tenuous, legal tenure to land or property [10]. That this is a situation of major injustice, that engineers have the skills to ameliorate this injustice, and that this gives rise to at the very least an oppoitunity of professional capabilities, provide the basic motivations for taking an active role in such poverty reduction. 

Geological hazards vary in their nature and can be complex. One type of hazard, for example, an earthquake, can be responsible for the generation of others such as liquefaction of sandy or silty soils, landslides or tsunamis. Certain hazards such as earthquakes and landslides are rapid onset hazards and so give rise to sudden impacts. Others such as soil erosion and subsidence due to the abstraction of groundwater may take place gradually over an appreciable period of time. Furthermore, the effects of natural geohazards may be difficult to separate from those attributable to human influence. In fact, modification of nature by humans often increases the frequency and severity of natural geohazards, and, at the same time, these increase the threats to human occupancy. 

Song, L.S. 1994. Historical earthquake and landslide disaster. Earthquake Research in Shanxi, (2), 55-57. (in Chinese). 

ABSTRACT The probable overall interrelation between seismicity background and landslide activity was focused in this study. The comparative analysis of spatial-temporal distribution of earthquakes and landslides has been made in two earthquake and landshde-active areas in Kyrgyzstan Northern Tien-Shan and Western Tien Shan. Data on active faults, modem tectonic movements and earthquake sources mechanisms have been analyzed for the estimation of the geodynamic conditions of the study area. Atmospheric precipitations influence on the activation of the landslide processes was also taken into consideration. 

LESSLOSS. 2006. Risk Mitigation for Earthquakes and Landslides. Integrated Research Development Project of the European Commission. Deliverable 78 — Applications of probabilistic seismic assessment methods to selected case studies. Sub-Project 9 - Probabilistic risk assessment methods and applications, http //www.lessloss.org. 

Project LessLoss on Risk Mitigation for Earthquakes and Landslides, Sub-Project 10 -Earthquake disaster scenario predictions and loss modelling for urban areas, Sixth Framework Programme. 

Spence, R., Pitilakis, K., Kakderi, K., Ansal, A., Erdik, M., Costa, A.C., Sousa, M.L. 2006b. Revised Loss Estimates Based on Alternative Mitigation Actions and Evaluation, Deliverable 115, Project LessLoss on Risk Mitigation for Earthquakes and Landslides, Sub-Project 10 -Earthquake disaster scenario predictions and loss modelling for urban areas. Sixth Framework Programme. 

This chapter discusses several major related aspects of the geosphere. It considers destructive geospheric phenomena, especially volcanic eruptions, earthquakes, and landslides, and what can be done to cope with these often catastrophic phenomena. This chapter discusses preservation of the geosphere and modifications to it that can preserve and enhance geospheric quality, such as conversion of contaminated areas back to safe and prodnctive uses. In addition, the geosphere is considered in this chapter as a source of raw materials, especially essential elements and metals and the environmental and snstainability challenges posed by the acquisition of these materials from Earth. 

Several risk identification methods were put in place in the city prior to 2004. These include compilation of records of hazard events, generation of hazard maps, studies of physical and social vulnerability, and studies of environmental degradation. One of the means of reducing risk firom earthquakes and landslides in Bogota is the assessment of seismic risk of bridges, hospitals, and schools. This has become a core part of the city s economic and social development plan. Of these assessment programs, the best-known... 

Pain, C. F. (1972). Characteristics and geomorphic effects of earthquake initiated landslides in the Albert Range of Papua New Guinea. Eng. Geol. 6, 261-274. 

Risk is the probability of harm or loss and can be considered to be a product of the probability and the severity of specific consequences. Risk, as it relates to hazardous wastes and groundwater contamination, may be defined as the chance that humans or other organisms will sustain adverse effects from exposure to these environmental hazards. Risk is inherent in the life of all organisms—humans, animals, and plants. Tornadoes, landslides, hurricanes, earthquakes, and other natural disasters carry a risk of injury or death to any living thing in their path. Similarly, human-caused risks such as automobile accidents, plane crashes, and nuclear disasters occur with varying levels of severity. 

Other causes of waves include undersea landslides, volcanic eruptions, and movement along faults on the ocean floor. Fault movements can suddenly raise or lower the seabed, resulting in earthquakes and displacing water. The displaced water forms a gigantic wave called a tsunami (sometimes referred to as a seismic or tidal sea wave). 

Garwood, N. C., D. P. Janos, and N. Brokaw (1979). Earthquake-caused landslides A major disturbance to tropical forests. Science 205, 997-999. 

Comparisons of time-scales for various physical processes have been discussed by Lerman (1979) and Schwartzenbach and Imboden (1984). In general, physical processes in lakes have characteristic times in the range of 10 to 10 years. Oceanic processes span times from days to thousands of years (Broecker, 1974) and geological events may occur catastrophically (e.g. earthquakes or landslides exposing new weathering surfaces) or very slowly. 

Earthquakes cause ground movement that causes destruction of rigid structures and liquefaction i.e. the sudden loss of strength of water saturated sediment. The ground movements also trigger mass movements like mudflows and landslides. 

Khazai, B. and Sitar, N. 2004. Evaluation of factors controlling earthquake-induced landslides caused by Chi Chi earthquake and comparison with the Northridge and Loma Prieta events. Engineering Geology, 71, 79-95. 

ABSTRACT The question why our Earth s crust is not quiet has been asked by many people. Many answers or hypotheses to the question have been proposed over last several thousand years. The author has put forward a hypothesis of originality to answer the question. His hypothesis is that there is a thin spherical gas layer between the crust and mantle. It is of a thickness from several hundred meters to few kilometers. It separates and protects the cold crust rocks and the hot mantle and core materials. Leak, migration and expansion of the highly compressed and dense gas along deep faults and orogens in the crust into the middle and upper crust rocks cause the crust unstable. The physical and mechanical interactions and/or chemical reactions between the gas and the crustal rocks cause crustal unstable phenomena including earthquakes, volcanos, landslides and tsunamis. 

Yue, Z.Q. 2013a. Natural gas eruption mechanism for earthquake landslides Illustrated with comparison between Donghekou and Papandayan rockslide-debris flows, in Earthquake-induced Landslides, K. Ugai et al. (eds.), Springer-Verlage Berlin, Chapter 51 pp. 485-494. 

Wenchuan earthquake triggered tens of thousands rockfalls and landslides. Many of them were distribution in mountains and canyons areas. Based on the field investigation and monitoring it could get following conclusions ... 

The heavy rain that poured after the earthquakes on September 10 resulted in heavy mudflow. Consequently, 63 people were injured, 100,000 residents were displaced, traffic was brought to a halt, and economic losses skyrocketed in the earthquake-struck region Lei et al., 2012). Aside from the heavy rains, other conditions that caused the mudflow were the vast distribution of loose accretions of debris from the collapses and landslides triggered by the earthquakes and from the rock masses also shattered by the earthquakes. The heavy rain induced many new landslides and collapses from these shattered rock masses. The loose accretions of debris from the collapses and landslides were transported in large quantities to the Luoze River and then carried to the lower reaches by floods. The flood turned to heavy mudflow that hit the residential areas, especially Yiliang County Town. The streets were covered by mudflow accretions that were half a meter thick Lei et al, 2012). 

Correlations of earthquake-triggered landslides volume and seismogenie fault A ease study of the 12 May 2008 Wenehuan earthquake, China... 

Landslides occurred before earthquake should be exclude, and landslides occurred after the earthquake triggered by rainfall or other triggers also should be exclude. 

Rodriguez, C.E., Bommer, J.J., Chandler, R.J. 1999. Earthquake-induced landslides 1980-1997. Soil Dynamics and Earthquake Engineering, 18(5) 325-346. 

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