地震道时间域频率属性特征和地层层序划分

在高分辨率地震勘探中，地震频率属性除了能反映地下不同级次的层序界面外，还携带着层序内部结构信息。本文试图应用时频分析技术研究地震道频率属性特征与层序内部结构的关系，提高对低级次层序单元的识别精度。研究表明，时间域频率值、频团能量、频支时间厚度的变化及分叉结构、横向展布规律和组合样式、多期时频层序的形成，与地层属性、沉积旋回间存在着较明显的对应关系。直接利用频率属性的各种特征，能够从不同角度更合理地划分多期次旋回的各类时频层序，可以较准确地分辨出较低级次的层序细节，从而实现对薄储层的高精度预测。

Frequency attributes characters of seismic traces in time domain and division of stratigraphic sequence.

In high-resolution seismic exploration, apart from reflecting the underground sequential interfaces in different levels, seismic frequency attribute also includes sequence-internal structural information. Using time-frequency filtering technique to study the relationship between the frequency attribute character of seismic traces and sequence-internal structures can improve identified precision of sequence strata. The study showed that the frequency value in time domain, energy of frequency cluster, variation of time thickness of frequency branch and its branched structure,lateral spreading regularity and array pattern and formation of multi-periodic time-frequency sequences have obviously corresponding relationship with stratigraphic attributes and sedimentary cycle. Directly using the variety of characters of frequency attributes can more reasonably divide different kinds of multi-periodic and multi-cyclic time-frequency sequences at a different angle,which can more accurately identify lower levels of sequential details and realize high-precise prediction of thin beds.