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1976年—1978年间,澳大利亚矿产资源局在澳大利亚东部七北个地区的正常沉积盆地勘查期间,通过简单地把记录时间延长到16秒,在长达15公里连续剖面上记录到了深部地壳的反射资料。记录剖面上显示出强度、连续性、倾斜以及空间分布变化的许多波组。把较长的和较短的垂直测线剖面进行比较,有可能区分开一次反射波与绕射波、多次反射波和其它干扰波。根据反射波的特征,可以把反射波分成几个区带并可根据地壳的性质和结构来解释。大多数反射剖面都显示出,在沉积反射层下面有一个薄的<2—3秒>无反射区带,被一个厚的<9秒以上>由许多反射段组成的射区带所覆盖,反射段的厚度和分布都是变化的。这样,所得资料可以认为,整个澳大利亚东北部,在沉积层之下,上地壳的地震特征是相似的。另一方面,在佐治亚盆地和德拉蒙德盆地下面,更深处的地壳的地震特征和厚度与鲍温盆地和加利里盆地北部边缘下面的差异很大。可以得出结论:在沉积盆地勘探期间,使用现代多次共深度点覆盖技术,可以记录到质量高的深部反射;在长测线、交叉排列及扩展排列上记录的资料所提供的地壳和上地幔结构和成分的信息,其分辨率比以往可能得到的更高。一般说来,这样的信息在研究矿产及石油产区和岩石圈的演化时是很有价值的.
Between 1976 and 1978, the Australian Bureau of Mineral Resources recorded deep crusts on successive sections up to 15 kilometers by simply extending the recording time to 16 seconds during normal depositional basin exploration in seven northern regions of Australia Reflection of information. A number of wave sets showing changes in intensity, continuity, tilt, and spatial distribution were recorded on the profiles. By comparing longer and shorter vertical line profiles, it is possible to distinguish between primary reflected and diffracted waves, multiple reflected waves and other interfering waves. According to the characteristics of the reflected wave, the reflected wave can be divided into several zones and can be interpreted according to the nature and structure of the crust. Most reflection profiles show that there is a thin <2-3 second> non-reflective zone below the deposited reflector that is covered by a thick shot zone consisting of many reflective segments <9 seconds or more, the reflection The thickness and distribution of the sections vary. Thus, the data obtained suggest that the seismic characteristics of the upper crust beneath the sediments are similar across the northeastern Australia. On the other hand, beneath the Georgia basin and the Drummond basin, the seismic characteristics and thickness of the deeper crust are quite different from those below the northern edge of the Bowen and the Galilee basins. It can be concluded that during the exploration of the sedimentary basin, the use of the modern multi-point co-depth point (CDP) coverage technique allows for the recording of high-quality deep reflections; the data recorded on long-term alignment, cross-alignment and extension arrangements The information on the structure and composition of the crust and upper mantle has a higher resolution than ever possible. In general, such information is valuable in studying the evolution of mineral and oil-producing areas and the lithosphere.