Landslides caused by earthquakes 1984 book 2

Waterlevel changes rapid lowering of water levels can trigger landslides, especially along dams, coastlines, reservoirs, and rivers. Damage caused by earthquake landslides authorstream. Previous studies of worldwide earthquakes indicated that landslides occurred no farther than 36 miles from the epicenter of a magnitude 5. Researchers develop model for predicting landslides caused. For the western flank of the southern alps, new zealand, hovius et al. The examples underline the potential for the quantitative prediction of patterns of seismically triggered and induced landsliding, use of observed landslide patterns for study of earthquake mechanisms, and inclusion of. Beginning in 1984, syntheses of worldwide and national data on earthquakeinduced landslides have defined their general characteristics and relations between their occurrence and various geologic and seismic parameters. An earthquake can cause a slope to become unstable by the inertial loading it imposes or by causing a loss of strength in the slope materials. Twenty three people were killed, at least 167 injured, and more than 400 homes were. Fourteen types of landslides were identified in the earthquakes.

The discovery that the cascadia landslides were caused by a distant earthquake was an accident, johnson said. The additional use of geographic information system gis processing and digital mapping since about 1989 has greatly facilitated the level of analysis that can applied to mapped distributions of landslides. One of largest landslides known, green lake slide, is cubic kilometers in volume. The earthquakes of 1949, 1965, and the nisqually earthquake of 2001 produced numerous landslides throughout the puget sound region. The two blocks on a fault do not wait for an earthquake to be moved, it moves constantly without fault movement. Correlations between magnitude m and landslide distribution show. For sale by the books and openfile reports section, u. The earthquake left at least 29 people dead or missing, making it the deadliest earthquake in 1984. Landslides, earthquakes, and erosion sciencedirect. Investigating landslides caused by earthquakes a historical. Us geological survey, professional paper 1551c, pp. Download citation investigating landslides caused by earthquakes a historical. Signals of large landslides have been recorded by seismic networks around the world, and overall force estimates have been previously determined for large landslides using longperiod waves. Keefer 1984 classified earthquakeinduced landslides into three main.

What makes this new study so unique is that it provides direct observational evidence from the largest earthquake to occur in more than 100 years in the eastern u. Each type of earthquakeinduced landslide occurs in a particular. Most of the landslides were concentrated in a km 2 area that included the santa susana mountains and the mountains north of the santa clara river valley. Landslides can be triggered by an earthquake, either by an increase in shear stress or due to decrease in soil strength. Many human caused landslides can be avoided or mitigated. Arial calibri default design rapid changes on earth. Distant earthquakes can cause underwater landslides. The 17 january 1994 northridge, california, earthquake m w 6. An average of 2550 people are killed by landslides each year in the united states.

This sample of 40 events was supplemented with intensity data from several hundred united states earthquakes to study relations between landslide distribution and seismic. This sample was supplemented with intensity data from several hundred us earthquakes to study relations between landslide distribution and seismic parameters. R geological survey, 345 middlefield road, ms 998, menlo park, california 94025 abstract data fro 4m0 historica worldwidl earthe quakes were studied t o determine th e characteristics, geologi environmentsc an hazardd, of s landslides caused by seismic events. Why do earthquakes trigger catastrophic landslides. Earthquake shaking can cause landsliding on many scales, as some of these examples show. Similarly, amongst the earthquakes in the database of rodr. Pdf characteristics of seismically induced landslides in. The study area is situated on the northwestern part of the indian plate. Beginning in 1984, synthesis of worldwide and national data on earthquakeinduced landslides have defined their general characteristics and relations between their occurrence and various geologic and seismic parameters.

Landslides triggered by the 1994 northridge, california. Landslides triggered by earthquakes in the central mississippi. Landslides kill more americans than earthquakes, but you. Analysis of landslides triggered by october 2005, kashmir. These materials and the predominant types of landslides in each are. Rapid prediction of the magnitude scale of landslide events. Most landslide fatalities are from rock falls, debrisflows, or volcanic debris flows called lahars. In the loma prieta, california, earthquake of october 17, 1989. We mapped landslides triggered by the earthquake in the field and from 1. For example, overall only large earthquakes typically m w. Hillside slid away from beneath this fourhundredfoot section of a union pacific railway branch line at tumwater, near olympia, washington, during the. Bulletin of the geological society of america 1984. The size, distribution, and mobility of landslides caused by the 2015.

Models of the triggering of landslides during earthquakes. Earthquakes are one of the main triggers that cause landslides. Landslides are particularly common in heavily forested areas of the northwest, triggered by rainfall and by earthquakes. Seismic landslide hazard for the cities of oakland and. Earthquake ground motion and patterns of seismically. Landslides, earthquakes, and a murderous tsunami all. However, the volume of instability can sometimes reach several. Landslides and mudslides can result from both volcanoes. According to the method proposed by keefer 1984, the magnitude scale of an. But scientists are wondering whether the findings could also shed light on the triggering of fast.

Earthquake triggered landslides have caused significant loss of life throughout history table 1. Before 1783, historical accounts of the occurrence of landslides in earthquake are typically so incomplete and. Landslides are frequently triggered by strong ground motions. Regional distribution and characteristics of landslides generated by the earthquake. A total of around 2500 landslides were triggered due to earthquake and.

The greatest losses of human life were due to rock avalanches, rapid soil flows, and rock falls. Landslides triggered by earthquakes in the central. Worldwide, landslides caused by earthquakes kill people and damage structures at higher rates than in the united states. Stress will build up until rocks cannot handle it and the blocks will spring back into place producing an earthquake. Map showing maximum distance at which landslides could have occurred during the 181112 earthquakes 2 3. Continued landsliding adds to the total erosion caused by an earthquake, reducing or possibly canceling seismic surface uplift. The most abundant of these were rock falls, disrupted soil slides, and rock slides. Detailed onsite investigation is required to determine the. Each type of earthquake induced landslide occurs in a particular. A more comprehensive definition which helps to distinguish landslides from the other geomorphological processes is the downward or outward movement of a mass of slopeforming material under the influence of gravity, occurring on.

The 1984 otaki earthquake hit nagano prefecture, japan on september 14, 1984, at 08. Earthquakeinduced landslides geotechnical photo album. They noted that the powerlaw tail is the most important part of the frequencyarea. The term landslide encompasses the downward lateral movement of earth materials due to gravity keefer, 1984. Data from 40 historical worldwide earthquakes were studied to determine the characteristics, geologic environments, and hazards of landslides caused by seismic events. Landslides triggered by the 3 august 2014 ludian earthquake in. Earthquakes, volcanoes, landslides magma is a landslide is a volcano is. Sensitive instruments installed on and near the slowmoving landslide in maca, peru, have allowed scientists to observe the response of the landslide to earthquakes. They are commonly a result of building roads and structures without adequate grading of slopes, poorly planned alteration of drainage patterns, and disturbing old landslides. Seismic recordings of landslides caused by typhoon talas. In our flybys, the landslides begin just south from cape campbell, becoming more intense south of the clarence river, with several large 100,000 500,000 m3 landslides disrupting both state highway 1 and south island main trunk railway e. The 17 january 1994 northridge, california, earthquake m6.

Landslides associated with earthquakes can contribute substantially. Mmvisee keefer 1984 and cotecchia 1987 for the effect of earthquakes. The term landslide includes a wide range of ground movement. Earthquake induced landslides in the himalayan mountains. Fourteen types of landslides were identified in the earthquakes studied. Widespread rockfalls also are caused by loosening of rocks as a result of ground shaking. Bulletin of the geological society of america 95, 406421 varnes d.

Generalized structure and stratigraphy of the bluffs 3 5. Earthquakes intense shaking during earthquakes can cause the ground to fail. Landslides caused by earthquakes gsa bulletin geoscienceworld. Solid rock and bowls of jello living with earthquakes. The first historical inventory includes 44,724 landslides in the umbria area of italy estimated to have occurred in the last 510 ky thousand years.

Over the years, the interactions between land, ocean, biosphere and atmosphere have increased, mainly due to population growth and anthropogenic activities, which have impacted the climate and weather conditions at local, regional and global scales. The slide movements of about a meter caused extensive disruption to the station. The working party on world landslide inventory 1990 defines a landslide simply as the movement of a mass of rock, earth, or debris down a slope q. A total of 36 earthquakes worldwide are included, the new database having about the same number of earthquakes as reported by keefer. The grades of the selected shakemaps data table 2 show that none of them. Keeper, landslides caused by earthquakes, geological society of america bulletin, vol. Environmental news network landslides and earthquakes. This study focuses on the highfrequency waveforms and presents signals of 18 landslides caused. However, the volume of instability can sometimes reach. This paper traces the historical development of knowledge derived from these investigations.

I n some earthquakes, landslide s have denuded thousand osf square kilometres. Structure contour map of the mississippi embayment 3 4. A new classification of earthquakeinduced landslide event sizes. Damage caused by landslides during earthquakes david petley robert parker, nick rosser, alex densmore durham university, united kingdom huang runqiu, chengdu university of technology, china allahbuksh kausar, geological survey of pakistan lin jiunchuan, national taiwan university. The worldwide death toll per year due to landslides is in the thousands. Scientists had placed ocean bottom seismometers off the washingtonoregon coast to detect tiny earthquakes, and also to measure ocean temperature and pressure at the same locations. Landslides and volcanic activity landslides due to volcanic activity are some of the most devastating types. Inventory of landslides triggered by the 1994 northridge.

Earthquake induced landslides have been documented from as early as 372 bc keefer, 1984 and have caused tens of thousands of deaths and billions in economic losses keefer, 1984. Muzaffarabad and balakot, the two most densely populated cities suffered most of the damage. Landslides, in and of themselves, constitute a major geologic hazard. Landslides are caused when the destabilizing forces acting on the earth of a hillside are greater than the stabilizing forces, meaning that one force overrides the other. Massive utah landslide triggered earthquakes live science. The main goal of the classification of earthquaketriggered landslide events is. In this section, we quantify erosion based on a event and historical landslide inventories, b earthquake triggered landslides, c aftershocks, and d seismicity on a global scale. The models of jibson and others 1998 and wilson 1993 are wellused alternatives among a number of viable models.