地震属性技术在煤田断层识别中的应用

摘要

Minor fault is essential in coal safety production. Can or cannot interpret structural forms of minor fault is the kernel always need to be solved in coal seismic prospecting. The seismic attribute technologies such as ant tracking, coherent energy gradient, vari⁃ance cube etc. with their differentiated attribute extraction and analytic capacities have greater indicative of faults, and become general technical means in fault interpretation at present. Taking a prospecting area in Huainan as an example, introduced features and effects of four kinds of seismic attribute technologies in fault interpretation. The variance cube attribute determines tectonic framework in the area, interprets three sets of fault with different trends;the coherent energy gradient can clearly indicate fault trend, for faults with dip 150o, definition of their coherent energy gradient slices reflected faults is higher than other azimuth slices;the spectral decomposition attribute fault identification ability is associated with frequency, high frequency spectral decomposition attribute slices can differentiate more easily;the ant tracking attribute can depict strata discontinuity more exquisite, clearly identified minor faults with displacement about 5m in the area.%小断层是影响煤炭安全生产的一个重要因素。能否准确解释小断层的构造形态一直是煤炭地震勘探需要解决的核心问题。地震属性技术如蚂蚁追踪、相干能量梯度、谱分解、方差体等以其差异化的属性提取和分析能力，对断层具有较强的指示性，已成为当前断层解释中的常规技术手段。以淮南某工区为例，介绍了四种地震属性技术在断层解释的特点与效果：方差体属性确定了本区大的构造格局，解释本区发育三组不同方向的断裂；相干能量梯度可以明示断层方向，对于倾向为150°的断层，其同方位的相干能量梯度切片比其它方位切片反映的断层清晰度高；谱分解属性对断层的识别能力与频率有关，高频率的谱分解属性切片更容易分辨小断层；同样蚂蚁追踪属性对地层不连续性刻画的更细腻，在本区对5m左右小断层都有清晰辨别。