厚黄土区地震勘探数据采集试验

Seismic Prospecting Data Acquisition Test in Loess Thick Region

宁中煤田九龙川矿井,属陇东黄土高原,黄土厚深度达270m。为提高该区地震勘探资料质量,进行了数据采集试验:首先进行低降速带调查及微测井,确定该区速度分层及深度;然后根据潜水位深度及硬土层深度,分别进行了单井不同深度、单井不同药量、多井组合、组合井不同药量等激发方式的试验,以及不同频率的检波器及同一频率检波器组合接收方式的试验。最终确定了该区的数据采集参数为单井深度为12m、6井组合、药量2kg的激发方式及60Hz检波器3串2并组合接收方式。通过在该区的地震勘探数据采集参数试验,发现10Hz检波器组合接收的地震资料,叠加后的剖面分辨率在局部地段甚至优于60Hz,但60Hz检波器采集的数据整体信噪比较高。

The Jiulongchuan coalmine of the Ningzhong coalfield is situated in the Longdong loess plateau with loess thickness 270m. To improve seismic prospecting data quality, has carried out data acquisition test. Firstly carried out low deceleration zone investigation and micro-logging to determine velocity layering and depth in the area, then according to phreatic water level and hard soil depth to carry out single hole different depths, charges and multihole assemblage assembled holes different charges shooting mode tests respectively; as well as different frequency geophones and same frequency geophone assemblages receiving mode test. Finally have determined data acquisition parameters in the area are single-hole depth 12m, 6 holes assemblage, charge 2kg shooting mode and 60Hz geophone 3 series 2 parallels assemblage receiving mode. Through seismic prospecting data acquisition parameter test, has found that the 10Hz geophone assemblage received seismic data, section resolution after stacking even better than 60Hz geophone assemblage in local areas, but the overall signal to noise ratio is higher of the data acquired by the later.