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在常温常压条件对中国大陆科学钻CCSD主孔岩心的700样品进行了弹性波速度测量,并建立了主孔2000m的波速(Vp和Vs)连续剖面,为检验地球物理模型的合理解释提供了岩石物理学方面的宝贵资料。主孔中新鲜榴辉岩纵波速度(Vp)最大(7.86km/s),正副片麻岩波速最小,又分别为5.53km/s和5.71km/s,榴辉岩的波速随着退变质作用的增强而明显减小。主孔2000m总平均Vp速度为6.2km/s,它与地球物理探测方法获得的大别-苏鲁造山带上地壳具有6.2-6.3km/s 高速层结论是一致的。大部分岩石具有明显地震波各向异性。水饱和度使岩石纵波(Vp)速度和剪切波速度(Vs)分别增加19％和6％,而使Vp的各向异性降低3％-4％。不同岩性界面的反射系数(Rc)是产生地震反射的主要原因。金红石榴辉岩与片麻岩之间具有很高的反射系数(0.24-0.31)。韧性剪切带中糜棱岩化片麻岩和面理化榴辉岩使岩石各向异性和反射强度明显增加。岩石微裂隙与主孔原位波速变化有密切关系。饱水岩石速度(Vp和Vs)可以代表CCSD主孔原位状态的地震波速度。上述成果为本区地震反射体成因提供了重要的岩石物理性质约束。
The elastic wave velocities of 700 samples of the CCSD main hole of the Chinese mainland were measured at normal temperature and pressure conditions and the continuous velocity profiles (Vp and Vs) of the main hole at 2000m were established to provide reasonable explanations for geophysical models Invaluable information on petrophysics. The main eclogite possesses the largest (7.86km / s) P wave velocity and the smallest plutons (5.53km / s and 5.71km / s), respectively. Of the increase and significantly reduced. The total average Vp velocity at main site of 2000m is 6.2km / s. It is consistent with the conclusion that the crust in the Dabie-Sulu orogenic belt obtained by geophysical exploration has a velocity of 6.2-6.3km / s. Most rocks have significant seismic anisotropy. The water saturation increases the Vp and Vs by 19% and 6%, respectively, and decreases the Vp anisotropy by 3% -4%. The reflection coefficient (Rc) at different lithologic interfaces is the main reason for seismic reflection. Aucite eclogite and gneiss have a high reflection coefficient (0.24-0.31). Mylonitized gneisses and physicochemical eclogites in ductile shear zones increase rock anisotropy and reflection intensity significantly. Rock microcracks and the main hole in situ velocity changes are closely related. The water-saturated rock velocities (Vp and Vs) represent the seismic wave velocity in situ of the CCSD main hole. The above results provide important petrophysical properties for the genesis of the seismic reflector in this area.