坡折带地震定量识别方法

A seismic quantitative identification method of slope break belt

根据坡折带坡度的变化特征,结合地貌学中坡度理论,将坡度和坡向作为一种层面属性,建立了一种基于精细地震解释层位和坡度属性的坡折带定量识别方法,并综合采用理论数学曲面模型、地层倾角测井、地层厚度等值线、地震属性等资料对该方法进行了验证。对准噶尔盆地车排子地区下白垩统清水河组坡折带的定量识别结果表明,该方法计算的地层坡度与井下地层倾角测井资料所反映的地层倾角一致,所识别的坡折带分布区与该地区地层厚度变化趋势和已发现的地层岩性油气藏分布范围相符合,且利用坡度属性识别坡折带效果优于地层倾角属性,该方法能量化几何参数包括坡折带的坡度、高差、水平宽度、坡脚、坡折等。

Based on the slope variation characteristics of slope break belt and slope theory in geomorphology, a method, which can quantitatively identify the slope break belt based on the precise seismic horizon data and slope and aspect attribute, was established, and the mathematic surface model, dip logging, seismic attributes, and formation thickness contours were used to verify this method. Then, this method was used to quantitatively identify the distribution range and geometric parameters of the slope break belt in the Lower Cretaceous Qingshuihe Formation in Chepaizi area of Junggar Basin, NW China, the results show that the formation slope calculated by this method is consistent with that reflected by the dip logging data, the distribution range of the slope break belt identified by this method is in line with the trend of the formation thickness and the distribution range of the discovered stratigraphic-lithologic reservoir, and the slope attribute is better than formation dip attribute in identifying the slope break belt. The geometric parameters of the slope break belt which this method can identify are the accurate location of slope break and slope toe, the value of the slope and the height difference and width between the slope break and slope toe.