“两宽两高”地震勘探技术及应用成效

"Two widths and two heights"seismic exploration technology and application results

宽方位、宽频带、高密度(简称“两宽一高”)地震采集技术在解决低信噪比地区勘探、复杂地质体成像等难题方面具有明显的技术优势。随着复杂地层岩性和非常规油气藏等隐蔽性油气藏勘探的不断深入,地震资料的保真度要求大幅度提高。提高保真度需要野外地震采集采用宽频超高灵敏度传感器,提高弱信号记录能力,消除激发和接收的组合效应以及解决从近地表至目标层的地层吸收衰减问题。为此,提出了宽方位、宽频带、高密度、高保真(简称“两宽两高”)的地震采集理念,经过多年实践与发展,形成了“两宽两高”单点三维地震勘探技术。高保真的核心是野外采用高灵敏度的检波器,提高数据记录动态范围,单点接收消除组合效应,既提高弱信号记录能力,又消除组合带来的检波器时差问题,降低近地表起伏和速度差异带来的静校正、速度拾取等影响保真度的问题。“两宽两高”地震勘探技术提出后,率先在长庆油田、辽河油田、四川油田等探区进行了试验,均取得了良好的应用效果。随着节点地震采集系统和“双高”地震处理、真地表地震成像等技术的全面推广应用,目前“两宽两高”地震勘探技术已成为中国石油陆上油气勘探开发的主要技术。

Wide azimuth,wide band and high density(referred to as"two widths and one heights")seismic acquisition technology has obvious technical advantages in solving exploration problems such as low signal-to-noise ratio area exploration and complex geologic body imaging.However,with the deepening of complex stratigraphic lithology exploration,unconventional oil and gas exploration and other hidden oil and gas reservoirs,the requirement of seismic data fidelity has been raised to an unprecedented level.To improve the fidelity,broadband ultra-high sensitivity sensors should be used in field seismic acquisition to improve the ability of weak signal recording.The second is to eliminate the effect of combination excitation and reception.The third is to solve the problem of formation absorption attenuation from near surface to target layer.For this reason,the concept of wide azimuth,wide band,high density and high fidelity(referred to as"two widths and two heights")seismic acquisition is put forward.After years of practice and development,a single point 3D seismic exploration technology of"two widths and two heights"is formed.The core of high fidelity is the use of high sensitivity detector in the field,improve the dynamic range of data recording,single point reception to eliminate the combination effect,improve the weak signal recording ability,and eliminate the combination caused by the geophone time difference,reduce the near surface fluctuation and speed difference caused by static correction,speed picking and other problems affecting the fidelity.After the"two widths and two heights"seismic exploration technology was put forward,it was first tested in Changqing oilfield,Liaohe oilfield,Sichuan oilfield and other exploration areas,and good application results were achieved.With the comprehensive promotion and application of nodal seismic acquisition system,"two heights"seismic processing,true surface seismic imaging and other technologies,the"two widths and two heights"seismic exploration technology has been fully promoted in PetroChina,and has become the main technology of onshore petroleum exploration and development of Petrochina.