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较大的隐伏在地堑内部的地垒,一些大的侵入体,形变的变质岩体。地壳和地幔的分界面以及在地壳中部的岩浆集聚地带的地质特征,可以由大陆反射部面测量协会(COCORP)在里约格兰德裂谷(Rio Grandl rift)上所进行的工作来说明。作为其规划的部分工作。即把先进的地震反射技术应用于研究大陆地壳上的一些主要的地质问题.该协会在一九七五年和一九七六年于新墨西哥洲的Socrro 附近收集了二十四次迭加的155公里地震反射资料.其中包括一条长八十公里的穿过该裂谷的横向剖面,它西起 Sierra Iucero,东至 Manyano 山区。迭加反射剖面表明至少三十五公里的深度.可得到相关的反射能量。从这些研究结果中可以看出,该裂谷内的前寒武系基底被大角度的正断层普遍破坏。这就导致了实际所存在的隐伏的地形。在 Albuquerque 盆地的西南部发现了一个大的隐伏地垒,它大概和附近的 Sierra ladron 地块是相关的。这个裂谷的西部边界是被一个以中等角度(约40°)向东倾斜的反射层所划分。这个顷斜面在 Monte largo 先把地槽的两边缘和地层表面相交。裂谷的东部边界是与一个大倾角带状带有关.这一地带被一个相关反射的断块所确定,一直延伸到地壳的基底。裂谷内的基底特征是.无相关的地震能量的地震透射带,可能是均匀的深层岩体以及主要是很多短的(不足5公里)不连续的反射层段的地带。后一种看法是指对相应构造大量的破坏,例如,在一个形变的变质岩体中也许得到这种现象。在地壳中部深度,强而复杂的 P 波反射层在深度和倾斜方面同以前确定的岩浆体相对应。合成地震记录及频谱研究表明观察到的波形和地壳中低速的局部熔融体物质是一致的,但是对这种物质又不是唯一的。地震剖面显示了在地壳底部分层反射带复杂的间断性.而不是经常从折射的结果推断出那种简单的莫氏界面模型。地壳中的构造变化是该协会用反射剖面绘制的,这种构造变化也许在里约格兰德裂谷的发展过程及后来发生的演变中起着重要作用。
Large hiding in the graben within the horst, some large intrusion, deformation of the metamorphic rock mass. The interface between the crust and the mantle and the geological features of the magmatic accumulation zone in the middle of the crust can be illustrated by the work carried out by the COCORP in the Rio Grand Rift. As part of their planning work. That is, to apply advanced seismic reflection techniques to study some of the major geological problems on the continental crust. The Society collected twenty-four superimposed 155 near Socrro in New Mexico in 1975 and 1976 Km seismic reflection data, including a length of 80 km across the rift in the horizontal section, it west of Sierra Iucero, east to the Manyano mountains. The superimposed reflection profile indicates a depth of at least 35 km and the associated reflected energy is obtained. From these results, it can be seen that the Precambrian basement within the rift is generally destroyed by the large-angle normal faults. This led to the existence of the hidden topography. A large hidden basement was discovered in the southwestern part of the Albuquerque Basin, presumably related to the nearby Sierra ladron massif. The western boundary of this rift is divided by a reflective layer that is slanted eastward at a moderate angle (about 40 °). This slope is where Monte largo first intersects both sides of the trench with the surface of the formation. The eastern boundary of the rift is associated with a large dip belt that is defined by an associated reflection block that extends to the crust’s basement. The basement feature within the rift is that of seismic transmission without associated seismic energy, a zone that may be homogeneous deep rock mass and mainly short (less than 5 km) discontinuous reflection intervals. The latter view refers to the corresponding construction of a large number of damage, for example, in a deformed metamorphic rock mass may get this phenomenon. At the depths of the central crust, a strong and complex P wave reflector corresponds to the previously identified magma in terms of depth and tilt. Synthetic seismograms and spectral studies show that the observed waveforms are consistent with low-velocity local melt matter in the crust, but not uniquely for this material. Seismic profiles show the complex discontinuity of the stratified reflection band at the bottom of the crust, rather than the simple Morse interface model often deduced from the refraction results. Structural changes in the crust were drawn by the association using reflection profiles that may play an important role in the development of the Rio Grande Rift and its subsequent evolution.