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犁形正断层在沉积盆地形成中的重要性正在愈益明显。根据反射地震剖面和地面观测,可区分出以下四种发生类型:1.涉及基底的犁形正断层,这种基底伴有某些地壳减薄。这样的断层出现于裂谷形成期,这类裂谷常常先于被动陆缘的形成而出现(例如比斯开湾,加里西亚浅滩);2.表层松软沉积物的犁形正断层作用,与三角洲体系有关,或与和被动陆缘沉降相联系的漂移层系有关(例如墨西哥湾);3.与在活动陆缘产生的加积楔状体有关的犁形正断层作用(例如哥伦比亚);4.造山期和造山后的断层作用,它与造山系及其部分前沿地的引张及剪切有关(例如大盆地)。根据对大陆边缘和晚造山盆地的观测,正断层在“地槽”和褶皱带(例如阿尔卑斯)演化中的作用得到了被更好的理解。
The importance of plow-shaped normal faults in the formation of sedimentary basins is increasingly evident. Based on reflection seismic sections and ground observations, the following four types of occurrences can be distinguished: 1. Plow-shaped normal faults involving the basement with some crustal thinning. Such faults occur during the rift-forming period and such rifts often occur prior to the formation of passive margins (eg the Bay of Biscay, the Galician Shoal); 2. Plow-shaped normal faulting of loosely surfaced sediments and Delta system or related to drift stratigraphy associated with passive land-subsidence (eg the Gulf of Mexico); 3. plow-normal faulting associated with accretionary wedges generated at active margins (eg, Colombia); 4 The orogenic and post - orogenic faulting, which is related to the extension and shearing of the orogenic parts and some of their foreland (eg the Great Basin). Based on observations of the continental margin and the Late Paleozoic basin, the role of normal faults in the evolution of the “gnarls” and fold belts (eg the Alps) is better understood.