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高分辨声波测井能以极小的间距对地层进行采样.两个采样点之间的变化经常是很大的。分层的精细程度可与测井采样相同甚至更好.对于地震波传播,薄层介质可用等效均匀横向各向同性 TI 介适当质当平均值来表示,这种做法的前提是假设声波测井每个数据点所反映的是各向同性地层。这个假设往往在一个区域中因有很多薄泥岩层而不能成立,尽管如此,我们还是能在等效介质中得到准确的纵波和横波时差值.在变化剧烈的剖面中.在高分辨声波和密度测井曲线旁边,我们显示了计算出的长波的纵波和横波时差以及各向异性估算值,水平、垂直应力和声波偏移曲线,即从平均时差减去累计声波时差就得到了传播时差.纵波偏移值为正,上限值为1.5μs/ft,横波上限值为2.5μs/ft,当有比测井采样间距更薄的层或有一些明显的层内各向异性存在时(例如泥岩),以均匀介质为等效介质的各向异性将导致对实际各向异性情况的低估.由多分量多偏移距 VSP 测量得到的数据将提供非垂直资料,该资料是建立与声测井和地震观测最相吻合的缓慢变化的等效 TI 介质所必须的.
High-resolution sonic logging allows the formation to be sampled at very small intervals, and the variation between the two sampling points is often large. Stratification can be as fine as well logging samples or even better. For seismic wave propagation, thin-layer media can be characterized by equivalent homogeneous transverse-isotropic TI media as an average, assuming that acoustic logging Each data point reflects an isotropic formation. This assumption is often not possible with many thin mudstone layers in a region, but nevertheless we can obtain accurate P-wave and S-wave time differences in equivalent media. In highly variable sections, high-resolution acoustic waves and Next to the density log, we show the calculated longitudinal and transverse wave time and anisotropy estimates, horizontal and vertical stress, and acoustic wave offset curves for the long wave, ie, the propagation time difference is obtained by subtracting the cumulative acoustic wave time difference from the average time difference. The longitudinal wave offset is positive with an upper limit of 1.5 μs / ft and a transverse wave upper limit of 2.5 μs / ft. When there is a thinner layer than the well sampling interval or with some significant intra-layer anisotropy Such as mudstone), the anisotropy of a homogeneous medium as an equivalent medium will lead to an underestimation of the actual anisotropy. The data measured by the multi-component multi-offset VSP will provide non-vertical data that is used to establish harmony with the sound Logging and seismic observations are most consistent with slowly changing equivalent TI media.