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or lateral spreading is likely to cause significant to major damage to affected buildings or infrastructure. For the Eugene/Springfield Metro Area, a DOGAMI study of areas with soil types prone to amplification of seismic ground motions found scattered pockets of moderate hazard soils scattered throughout the Eugene/Springfield Metro Area. In total, these areas cover perhaps 10% of the total area ((DOGAMI, Relative Earthquake Hazard Map of the Eugene-Springfield Metropolitan Area, Lane County, Oregon IMS-14, 2000). These DOGAMI maps of Relative Amplification Hazard Zones are shown below as Maps 6E and 6S, for Eugene and Springfield, respectively. There are significant portions of both Eugene and Springfield identified on Maps 6E and 6S as moderate amplification hazard. One area of high hazard was identified in the southwestern part of Eugene, in the vicinity of West 11th Avenue and Green Hill Road. Some of these moderate and high hazard areas for amplification may also be subject to liquefaction, settlement, and lateral spreading. However, specific areas potentially subject to these hazards have not yet been mapped. t0,3.2 Landslides Earthquakes can also induce landslides, especially if an earthquake occurs during the rainy season and soils are saturated with water. The areas prone to earthquake- induced landslides are largely the same as those areas prone to landslides in general. As with all landslides, areas of steep slopes with loose rock or soils are most prone to earthquake-induced landslides. Maps 4E and 4S (Chapter 8~ shows areas of the Eugene/Springfield Metro Area subject to earthquake-induced (and other) landslides, To date, relatively limited development has occurred in these high landslide potential areas although a few homes and streets/roads are located in these areas. See Chapter 8 for further discussion of landslide hazards, Dam Failures Earthquakes can also cause dam failures in several ways. The most common mode of earthquake-induced dam failure is slumping or settlement of earthfill dams where the fill has not been properly compacted. If the slumping occurs when the dam is full, then overtopping of the dam, with rapid erosion leading to dam failure is possible. Dam failure is also possible if strong ground motions heavily damage concrete dams. In a few cases, earthquakeqnduced landslides into reservoirs have caused dam failures. Earthquake-induced dam failures are addressed in more detail in Chapter 12 which covers dam failures that could affect the Eugene/Springfield Metro Area. 10.3,4 Tsunamis and Seiches Tsunamis, which are often incorrectly referred to as "tidal waves," result from 10-9