利用检波器串获取井口时间的方法探讨  

Approach to Obtaining the Up-hole Time Value in Seismic Exploration

作　　者：曹雄伟 司亚 陶林 谢廷益 李国圆 张学银 

机构地区：[1]东方地球物理勘探有限责任公司新兴物探开发处,河北涿州072750 [2]东方地球物理勘探有限责任公司装备服务处,河北涿州072750 [3]东方地球物理勘探有限责任公司采集技术支持部,河北涿州072750 [4]东方地球物理勘探有限责任公司国际勘探事业部,河北涿州072750 [5]东方地球物理勘探有限责任公司华北物探处,河北任丘062522

出　　处：《石油管材与仪器》2017年第6期75-78,86,共5页Petroleum Tubular Goods & Instruments

摘　　要：地震勘探中井口时间的大小取决于炸药的激发深度和地震波的传播速度,在巨厚腐殖质区域的井口时间可达到100 ms以上,超出了SHOTPROII爆炸机的接收时间范围,爆炸机无法接收到正确的井口时间。为了爆炸机获取正确的井口时间,提出了一种新的方法,在井口旁另外插一支SG10检波器,连接大线,直接用地震仪器接收,读取该道初至时间来修正爆炸机的井口时间。通过和正确的井口时间、最近道的初至时间对比,证明了该方法的可行性。随着腐殖质层厚度的加大,采集到的初至时间出现延迟,通过对地震波和对单支SG10检波器类型进行分析,出现初至延迟的原因是单支SG10检波器接收到的地震波初至能量弱,无法准确起跳。将单支SG10检波器改为单个JSX-2检波器,得到了正确的初至时间。随着腐殖质层厚度的继续加大,采集到的初至时间再次出现延迟,通过将单个JSX-2检波器改为1串(12个)SG10检波器,得到了正确的初至时间。The up-hole time value t in seismic exploration is up to the shooting depth and the near-surface velocity of each shooting well. Inthe thick humus area, the up-hole time value t may be more than 100 ms because of the low velocity layer, which beyond the range that theblaster can receive. In order to obtain the accurate t value, the paper give a new method, a geophone was planted near the shot and directlyconnected to the acquisition instrument by cable. The first break time of the geophone is equal to the up-hole time value t . It is proved thatthe method is useful to obtain the up-hole time value t by comparing with some up-hole time value t and the first break time of the nearesttrace. In some case, the up-hole time has delayed because of the thickness increasing of the humus area. By Analyzing seismic wave andthe type of single SG10 geophone, the reason for the initial delay is that the seismic waves received by the single SG10 detectors are tooweak to jump accurately. Though changing a single SG10 detector to a single jsx-2 detector, the right first time acquires. With the thicknessincreasing further of the humus area, the up-hole time delay appears again, the paper give a solution to use 12 geophones in series to getfirst break time, and can receive the right first break time.

关 键 词：地震勘探 井口时间 巨厚腐殖质 爆炸机 大线 最近道 

分 类 号：P631.4[天文地球—地质矿产勘探]