The hydraulic profiling tool (HPT) has become one of the basic tools for investigation of soils and unconsolidated formations over the last 10 years. The HPT is advanced into the subsurface using direct push methods. Clean water is injected into the formation from a small screened port on the side of the probe as it is steadily advanced into the subsurface. A downhole pressure sensor detects the pressure required to inject the water into the formation while an up‐hole flowmeter monitors the water flow rate. An electrical conductivity (EC) array included in the lower end of the probe provides a simultaneous EC log of the bulk formation. The EC log, HPT pressure, and flow rate are logged and displayed onscreen as the probe is advanced. These logs enable the investigator to evaluate vertical changes in relative formation permeability at high resolution. Pressure dissipation tests may be performed at selected depths in coarse‐grained materials to determine the piezometric pressure in saturated formations. This enables the operator to define the piezometric profile and determine the piezometric surface without a well. Post processing of the log in the viewing software provides for calculation of the corrected HPT pressure (Pc) and estimation of hydraulic conductivity (Est. K) within limits (~0.1 to 75 ft/d). In clean, coarse‐grained materials the tandem EC log may be used to estimate groundwater specific conductance based on an Archie's Law model. Cross sections of HPT logs provide an efficient means to define hydrostratigraphy. When combined with contaminant logging tools such as the membrane interface probe (MIP) the HPT data may help to define contaminant migration pathways or contaminated low permeability zones that may result in back diffusion. The HPT can be a useful tool for many geoenvironmental investigations in unconsolidated formations.

中文翻译：

---

疏松地层水文地质调查的水力剖析工具

在过去的十年中，水压剖面工具（HPT）已成为研究土壤和非固结地层的基本工具之一。使用直接推动方法将HPT推进到地下。当水稳步进入地下时，会从探头侧面的一个小的筛孔将清洁水注入地层。井下压力传感器检测将水注入地层所需的压力，而井上流量计监测水流量。探针下端包含的电导率（EC）阵列可同时提供整体结构的EC log。随着探头的前进，将记录EC日志，HPT压力和流速并将其显示在屏幕上。这些测井资料使研究人员能够以高分辨率评估相对地层渗透率的垂直变化。可以在粗粒材料的选定深度进行压力耗散测试，以确定饱和地层中的压强压力。这使操作员无需井就可以确定测压轮廓并确定测压表面。在查看软件中对日志进行后期处理，可以计算出校正后的HPT压力（Pc），并估算出极限（〜0.1至75 ft / d）内的水力传导率（Est。K）。在干净的粗颗粒物料中，串联EC测井曲线可用于根据阿奇定律模型估算地下水比电导率。HPT测井的横截面为定义水文地层提供了一种有效的方法。当与污染物记录工具（例如膜界面探针（MIP））结合使用时，HPT数据可能有助于定义污染物迁移途径或受污染的低渗透率区域，这些污染可能导致反向扩散。对于未固结地层中的许多地质环境调查，HPT可能是有用的工具。