硬岩地层爆破地震勘探的激发因素分析

Analysis on explosion parameters of blast seismic exploration in carbonatite rock

爆破地震勘探石油是一种重要的石油勘探方法,但受爆破参数、地质条件等影响.采用动力有限元软件ANSYS/LS-DYNA,研究了柱状、球状两种装药形状和爆炸当量等激发因素对碳酸盐岩岩石中爆炸应力波场特性和爆炸地震波能量衰减规律的影响,得到了爆炸参量对岩石应力、振动速度等的影响规律,并与爆破地震效应经验计算公式进行了对比分析.结果表明相同药量下球状装药爆炸时岩体中应力波强度较大,作用时间较长,而且药量增大时,装药形状的影响越来越明显;柱状、球状装药药量分别达到20kg、50kg时,能产生较好的爆破勘探激发能量和效费比.该结论可为优选适合西南地区碳酸盐地层地震勘探的激发因素提供技术途径和方法.图3,表5,参10.

Petroleum exploration with blasting seismic waves is an important method. But blasting seismic effects are influenced by blasting conditions and medium around. Effects of explosive configuration and quantity on properties of blasting stress waves and attenuating characteristics of blasting seismic waves in carbonatite rock were analyzed by numerical simulation with ANSYS/LS-DYNA software. The relationship of stress and vibration velocity and explosion parameters were attained. Results were compared with those calculated by empirical, formula. The analyses indicate that rock stress and loading time are bigger under spherical explosive configuration when explosive quantities of two configuration are equal. Intluence of explosive configuration on stress waves is affected and augmented by explosive quantity. The exploration energy and ratio of effect and expense is well produced when explosive quantity of cylindrical configuration is twenty kilograms and that of spherical configuration is fifty kilograms. The conclusion is a reference to select a proper method to seismic exploration in southwest region. 3figs., 5tabs., 10refs.