POSSIBLE CRITERIA FOR PREDICTING EARTHQUAKE LOCATIONS AND THEIR APPLICATION TO MAJOR PLATE BOUNDARIES OF PACIFIC AND CARIBBEAN
POSSIBLE CRITERIA FOR PREDICTING EARTHQUAKE LOCATIONS AND THEIR APPLICATION TO MAJOR PLATE BOUNDARIES OF PACIFIC AND CARIBBEAN
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DOI：
10.1029/jb078i014p02547
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发表时间：
1973-01-01
影响因子：
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通讯作者：
OLIVER, J
中科院分区：
文献类型：
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作者：
KELLEHER, J;SYKES, L;OLIVER, J
这项研究提出了几个可能的标准，用于预测不久的将来沿着主要板块边界的大型浅源地震的位置，并为这些预测分配一个粗略确定的评级。这些标准，其中一些是由其他研究人员提出的，是基于过去大地震的时空模式，其破裂带的横向范围，以及破裂传播的方向。这些标准分两个阶段适用。将第一套标准应用于沿着从智利到日本的太平洋东部、北方和西北部边缘的主要板块边界，也应用于西经74°以东的加勒比海圈，结果沿每个边界沿着划定了几个特别地震潜力区。本文中使用“特殊地震潜力”一词仅用于表示满足某些特定标准的板块边缘部分。然而，如果标准是有效的，至少有一些，也许是大多数大型浅源地震在不久的将来在检查区将发生在这些位置附近。目前，该标准的有效性还没有完全确立，基于这些预测的深刻社会变革也是不必要的，但这里提出的预测至少可以作为在大地震发生前选择深入研究和仪器的地区的指导。在近年来大地震破裂带几乎覆盖了地震带而只剩下几个空区的地区，该判据更有用。在某些具备补充资料的领域，随后适用第二套补充标准时，特别注意第一套标准划定的某些领域。根据余震位置、强度、海啸描述和海岸隆起确定的大型浅源地震的破裂带往往覆盖板块边界，而没有明显的重叠。由于这种倾向，以填补板块边界，因为大地震占如此高的比例，总地震矩释放的地震带，该地区的部分，最近没有经历过大地震是可能的位置，为未来的地震。沿着千岛-堪察加半岛地区、阿拉斯加-阿留申岛弧和南美洲西部的大部分地区，“大”地震往往是破裂带有时延伸数百公里的大地震。然而，沿着美国中西部，大地震的破裂带不超过100-200公里。虽然沿着加勒比海环的沿着某些部分发生过断裂长达数百公里的大地震，但其他某些部分却没有已知的大地震历史。因此，在加勒比海圈周围没有可识别的大地震。在这项研究中，几乎所有的板块边界的广泛部分都倾向于被大型浅源地震的破裂带所覆盖。因此，在大多数情况下，周期性的大地震似乎会减轻这里所考虑的板块边界沿着段的构造应变，而不管可能存在的断层蠕动和小规模地震。因此，除非出现相反的有说服力的证据，否则以无震蠕动为特征的断层段仍应被认为是发生大地震的潜在地点。对于所有的岛弧研究，主震的震中往往位于余震区的内侧或向陆地一侧。由于大多数岛弧附近的大地震发生在倾斜的断层面上，这种现象表明...
This study presents several possible criteria for forecasting the locations of large shallow earthquakes of the near future along major plate boundaries and for assigning a crudely determined rating to those forecasts. These criteria, some of which were proposed by other investigators, are based on the past space‐time pattern of large earthquakes, the lateral extent of their rupture zones, and the direction of rupture propagation. The criteria are applied in two stages. Application of the first set of these criteria to major plate boundaries along the eastern, northern, and northwestern margins of the Pacific from Chile to Japan and also to the Caribbean loop east of about 74°W results in delineation of several areas of special seismic potential along each of the boundaries. The phrase ‘special seismic potential’ is used in this paper only to indicate those segments of plate margins that fulfill certain specific criteria. However, if the criteria are valid, at least some and perhaps most large shallow earthquakes of the near future within the zones examined will occur near these locations. At present the validity of the criteria is not firmly established, and profound social changes based on these predictions are uncalled for, but the forecast presented here can, at the very least, serve as a guide in selecting areas for intensive study and instrumentation prior to the occurrence of a major earthquake. The criteria have greater usefulness in those regions where the rupture zones of large earthquakes have nearly covered the seismic zone in recent years and only a few gaps remain. In certain areas where additional information is available the subsequent application of a second set of supplementary criteria focuses special attention on certain of the areas delimited by the first set of criteria. Rupture zones of large shallow earthquakes as determined from aftershock locations, intensities, tsunami descriptions, and coastal uplift tend to cover plate boundaries without significant overlap. Because of this tendency to fill in the plate boundaries and because large earthquakes account for such a high percentage of the total seismic moment released in a seismic zone, segments of the zone that have not experienced a large earthquake recently are likely locations for future shocks. Along the Kurile‐Kamchatka area, the Alaska‐Aleutian arc, and much of western South America, the ‘large’ earthquakes tend to be great earthquakes with rupture zones sometimes extending many hundreds of kilometers. Along western Middle America, however, the large earthquakes have rupture zones no larger than 100–200 km. Although great earthquakes with ruptures hundreds of kilometers in length have occurred along some segments of the Caribbean loop, certain other segments have no known history of great earthquakes. Thus there is no recognizable class of large earthquakes around the Caribbean loop. Nearly all the extensive parts of the plate boundaries examined in this study tended to be covered by rupture zones of large shallow earthquakes. Therefore tectonic strain along segments of plate boundaries considered here appears to be relieved in most cases by periodic large earthquakes, regardless of the possible presence of fault creep and small‐magnitude earthquakes. Thus fault segments characterized by aseismic creep should still be considered potential sites for large earthquakes unless persuasive evidence to the contrary is forthcoming. For all island arcs examined, the epicenters of the main shocks tended to be located near the inner or landward side of the aftershock zone. Since most large earthquakes near island arcs occur on dipping fault planes, this phenomenon suggests that …