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解释海上地震资料时常见的问题是水底多次波与含构造信息及地层信息的一次反射波的干涉。在深水域有相当一部分一次反射波比一次简单水底多次波早到达,但弱的和深地壳反射往往被一次水底多次波淹没。为了获得更适于解释的剖面,研究了一种分两步处理的压制一次水底多次波的方法。第一步,为了消除地震子波的影响,即对资料进行子波整形,因而利用零次水底一次波及其一次水底多次波之间的关系,统计地求出地震反子波。这一子波处理提供了一种地下脉冲响应的带限估计。第二步,应用子波整形一次波能量的自褶积,确定性地估算和减去实际一次水底多次波。该法曾用于墨西哥湾深水域的野外资料。若输入的一次波和多次波的入射角不同,或者在倾斜界面的情况下,会引起不可补偿的旅行时误差,这些误差会降低压制多次波的能力,因此也限制了该法对共深度点叠加效果较差的低频信号的有效性。另外,弯曲界面也会使振幅预测产生一些问题。尽管如此,在经过倾角滤波的单道资料上,一次水底多次波得到明显地衰减(达18dB)。
A common problem when interpreting offshore seismic data is the interference of underwater multiples with a reflected wave that contains tectonic information and formation information. In the deep waters, a considerable part of the primary reflected wave arrives earlier than a simple underwater multiple, but weak and deep crustal reflections are often submerged by a submerged multi-wave. In order to obtain a more suitable interpretation of the profile, a two-step process to suppress the water bottom multiples of the method. The first step, in order to eliminate the influence of seismic wavelet, that is, the data wavelet shaping, and therefore the use of zero primary underwater and its primary underwater multiples of the relationship between statistically calculated seismic tonic wave. This wavelet processing provides a band-limited estimate of the underground impulse response. The second step is to apply the self-convolution of the primary energy of the wavelet shaping to deterministically estimate and subtract the actual primary underwater multiples. This method was used for field data in the deep waters of the Gulf of Mexico. If the angle of incidence of the incoming primary and multiple waves is different, or in the case of a tilted interface, an uncompensable travel-time error is caused which reduces the ability to suppress multiple waves and therefore limits the effect of this method on total The effectiveness of low-frequency signals with poorly-superimposed depth effects. In addition, bending the surface also causes some problems with the amplitude prediction. Nevertheless, a submerged multiple was significantly attenuated (up to 18 dB) on a single dip-dip filtered dataset.