时域激电单极-偶极、偶极-单极排列测深法二维地电断面成像

介绍了不对称测深法装置的测深原理;在吉林某地进行了激电测深勘探,结果显示:正向单极-偶极和反向偶极-单极采集的视电阻率、视充电率原始数据在拟断面图的分布特征,和大地电磁测深原始数据受到的静态效应类似,视电阻率、视充电率受局部地形和电磁噪声的影响,在拟断面图中呈假的带状异常。正向单极-偶极、反向偶极-单极装置获取的视电阻率、视充电率数据也可分别进行二维反演,但联合单极-偶极/偶极-单极装置测深二维反演地质结果最好,具有采集的数据量大、激电信号强 、穿透深度大、勘探精度高等优点,根据视电阻率、视充电率二维反演在地电断面成像技术,能够准确确定电性异常体的空间分布,为钻探验证电异常提供准确的地球物理依据。

POLE-DIPOLE/DIPOLE-POLE ARRAY SOUNDING TWO-DIMENSIONAL GEOELECTRICAL SECTION IMAGING FOR TIME DOMAIN INEDUCED POLARIZATION METHOD

The double current supply, inline and combined pole-dipole/dipole-pole array for time domain induced polarization method is an unsymmetrical arrangement sounding technology composed of forward pole-dipole and reverse dipole-pole array. This paper shows the sounding principle with graphical representation. For collecting resistivity and chargeability raw data distribution features in the pseudosection with forward pole-dipole and reverse dipole-pole array, it is similar to MT in that MT raw data obtain "static state effect", and resistivity and chargeability raw data also obtain "partial topography " and "electromagnetism noise" effect and assumes "false belt anomaly" features. Forward pole-dipole and reverse dipole-pole array obtains resistivity and chargeability data and can respectively process two-dimension inversion, but only the combined pole-dipole/dipole-pole array can get the best geological effect, indicating that the strongpoint of the electrodes configuration array is that it can obtain massive collection data, strong induced polarization signal, larger penetration depth and highly surveying accuracy. With the electrical property parameters for resistivity and chargeability two-dimension inversion imaging techniques in the geoelectrical section, we can accurately determine the spatial distribution of the electric anomaly body and can also provide accurate geophysical basis for drilling verification of the electric anomaly.