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用爆炸声源进行了海底反射特性的测量,获得了掠射角2°到85°之间的海底反射系数。应用一个多层的海底模型对海底反射系数进行了理论计算,在这个模型中,把最下层看成为固体的半无限空间。假设这些层是具有吸收的,而且各层之间有一个相互平行的分界面。对现场采集的底质样品测量了沉积物的声速,并应用于理论计算中,表明这一海区的海底是低声速沉积物,中间夹杂着一些薄的高声速层。在理论预言的一些角度上,示波器记录到的海底反射信号相对于入射波相位发生反转。将反射系数的理论值与实验值在1、2、和4千赫兹的频率上做了比较,一般说来,在整个范围内符合的较好。在贯穿角附近,发现测得的反射系数随着频率有一个奇异的增加,这大约可以用下层反射体的存在来解释。
The seafloor reflection characteristics were measured with an explosion source, and the seafloor reflection coefficient between 2 ° and 85 ° was obtained. A multi-layered submarine model is used to theoretically calculate the seafloor reflection coefficient. In this model, the lowest layer is considered as a solid semi-infinite space. It is assumed that these layers are absorbent and that the layers have a parallel interface with each other. Sediment velocity was measured on the sediment sample collected from the field and used in theoretical calculation. It shows that the seabed of this sea area is a low-sound-velocity sediment with a thin high-sound-velocity layer in between. In some aspects of theoretical predictions, the oscilloscope records the inverted seafloor signal relative to the incident wave phase. The theoretical and experimental values of the reflectance are compared at frequencies of 1, 2, and 4 kHz, and in general, it is better to be consistent over the entire range. Near the penetration angle, the measured reflection coefficient was found to have a singular increase with frequency, which can be explained by the presence of the underlying reflector.