地面微地震有源噪声自动识别与匹配压制方法

微地震监测技术通过对非常规储层压裂改造引发的震源点进行成像，实时提供压裂施工过程中产生的裂隙高度、长度、宽度和方位角等信息，为致密储层压裂提供指导，以提高油气采收率。在地面布设站点进行监测时，因微地震信号传播距离较远、近地表吸收衰减严重、地面有源噪声较多，微地震数据具有信号能量弱、噪声干扰强和信噪比低等特点，严重制约微地震事件的定位精度。噪声源多分布于地表，根据有源噪声与由储层向上传播的微地震事件在能量、频率、传播速度和源位置等方面的差异，本文提出微地震有源噪声自动识别与匹配方法。综合长短时窗能量比与微地震量板方法，自动识别有源噪声干扰，并进行噪声源位置和传播速度的三维最优并行搜索；利用同时确定的最优噪声源位置和传播速度对微地震数据进行动校正处理，得到噪声标准道，通过能量自适应匹配处理压制有源噪声。正演模拟数据和实际微地震数据去噪效果证明，本文方法能有效压制有源噪声，显著提高微地震数据品质，为后续微地震事件精确定位奠定了基础。

Microseismic active noise automatic identification and matching denoising

Microseismic data is characterized by weak energy and low S/N due to a long transmission distance, heavy subsurface absorption, and strong surface active noise, which seriously reduce the location accuracy of microseismic events.Since the active noise at the surface is different from microseismic events in the propagation direction, energy, frequency, velocity and source location, we propose a method of active noise automatic identification and matching denoiseing.According to the long-short window energy ratio and microseismic template chart method, the active noise can be automatically identified.The three-dimensional optimal parallel search for active noise source location and velocity are conducted at the same time, and the position of the active noise and noise propagation velocity are simultaneously determined.The optimal noise source location and velocity value are used in microseismic data processing to calculate the noise standard.Finally the active noise energy adaptive matching method is used to suppress noise.Tests on model and real data show the proposed method can effectively suppress the active noise, and improve the microseismic data quality, which effectively establish the foundation of subsequent precise location of events.