Vista Clara systems are the world’s only NMR logging tools that can be deployed using Direct Push technology from industry leader, Geoprobe Systems®.
Geoprobe® pioneered Direct Push Subsurface Sampling Technology in 1987. A direct push machine “pushes” tools and sensors (soil probes) into the ground without the use of drilling to remove soil and make a path for the tool. Geoprobe® direct push machines rely on a relatively small amount of static (vehicle) weight combined with percussion as the energy for advancing a tool string. Direct push tools do not remove cuttings from the probe hole but depend on compression of soil or rearrangement of soil particles to permit advancement for the tool string. Direct push tools or soil probes are advanced as far as possible using only the static weight of the carrier vehicle. Percussion is applied as required when advancing soil probes through sands, gravels, hard pans, high friction clays, tills, fill materials, and surface frost.
Deployment of Vista Clara Javelin and Dart tools in a Direct Push process provides rapid NMR logging results without the cost and hassles of pre-drilling boreholes in each situation.
Key advantages of direct push measurements also include:
- Ability to acquire downhole data with high efficiency and minimal footprint (small rig)
- Minimized environmental disturbance:
- No generation of drill cutting (which may be contaminated)
- No need to install permanent well (which could be a long-term liability)
- Very high quality NMR data because there is not disturbance from an oversized bit
Direct Push combined with the unique value of Vista Clara NMR measurement adds significant value above what can be achieved using other direct push tools, including:
- Direct measurement of total volumetric water content (or porosity if saturated)
- Estimation of mobile, capillary and clay bound water content. Mobile water content directly correlates to effective porosity
- Estimation of hydraulic conductivity over a range of 5-6 orders of magnitude, with maximum range up to 1000 m/day
- Measurement of all of the properties above at a resolution of 9 inches (25 cm)
- Vertical resolution of <4inches (<10cm)
- Deployment through Geoprobe’s standard 2.25 inch (57mm) direct push tooling.