Collaborative Research: An Asthenosphere-Lithosphere Probe in North America: An International Multi Scale-Seismic Experiment

9419021 1995年，加拿大岩石探测计划计划建立大陆规模的活动震源扩展扩展地震剖面，探测阿尔伯塔平原下的太古宙上地幔，探测的中点在梅迪辛哈特地块上方，梅迪辛哈特地块自元古代以来一直处于高位。这个DeepProbe剖面以卡尔加里附近为中心，沿着科迪勒拉西部的前部和内部有2500公里的口径。加拿大人将发射两个密集的接收器排列，每个大约600公里长，从卡尔加里向南延伸到美国，直到科罗拉多州和怀俄明州的边界。该项目是美国3个综合地震实验的组成部分，这些实验将补充加拿大的努力，利用类似的实验方法，但解决美国境内不同的构造和地质问题。这3个实验是：1)主动源扩展扩展大口径地幔探头，2)被动远震记录，3)地壳折射剖面。所考察的大范围尺度允许对完整的地壳-地幔系统进行地球动力学评估。美国的实验将调查科罗拉多高原/南落基山脉之下的显生宙软流圈和受显生宙构造作用改造的太古宙-元古界岩石圈。***

9419021 Levander In 1995 the Canadian Lithoprobe program plans a continental scale active source expanding spread seismic profile to probe the Archean upper mantle beneath the Alberta Plains, with the midpoint of the probe over the Medicine Hat Block, a crustal block which has been high standing since the Proterozoic. This DeepProbe profile, centered near Calgary, has a 2500km aperture along the front and interior of the western Cordillera. The Canadians will shoot into 2 dense receiver spreads, each roughly 600km long, extending from Calgary southward into the US to the Colorado-Wyoming border. This project is a component of a suite of 3 integrated US seismic experiments which will complement the Canadian effort, making use of similar experimental methodologies, but addressing different tectonic and geologic problems within the US. The 3 experiments are: 1) an active source expanding spread large- aperture mantle probe; 2) passive teleseismic recording and 3) a crustal refraction profile. The wide-range of scales examined permits geodynamic evaluation of a complete crust-mantle system. The US experiments will investigate Phanerozoic asthenosphere and Archean-Proterozoic lithosphere modified by Phanerozoic tectonism beneath the Colorado Plateau/Southern Rocky Mountains. ***