Directional drilling

When sowing crops, drilling in an east-west direction can provide better shadowing of interrow space and light interception by the crop. The occurrence of Apera spica-venti could be reduced more under erectophile cultivars drilled from east-west compared to north-south. The effect of planophile cultivars was similar in both drilling directions tested (Kbpke 2000). 

Subsequently the scientific research well was drilled as planned. When it penetrated Lower Ordovician carbonates it produced 16.3 x lO" m per day of natural gas. The scientific research well thus became the discovery well in this region. Since the well was drilled directly on the surface hydrocarbon gas anomaly, the soil gas survey traverse was thought to cross an apical or linear anomaly. Further work, however, was to reveal that the gas field has an annular anomaly. 

The principle is explained in Fig. 6.1. The tool-electrode is guided vertically and a force is acting on it in the drilling direction. The practical implementation of such a set-up is discussed later in Section 8.2. One important aspect is to reduce, as much as possible, the frictional forces that arise during the vertical guidance of the tool-electrode. 

Before Fermi and his team moved to Illinois they built one more exponential pile, this one loaded with cylindrical lumps of pressed uranium oxide three inches long and three inches in diameter that weighed four pounds each, some two thousand in all, set in blind holes drilled directly... 

Fossil remains are the remnants of plants and animals that lived during the time when the sediments that later became rocks were being deposited. For example, kettle bottoms are fossil trees that grew in ancient peat swamps and they occur in every U.S. coal basin, but are especially abundant in southern West Virginia and eastern Kentucky. Dinosaur footprints are another fossil remain found in the roof rocks of coal mines in Utah, Wyoming, and Colorado. Fossil r ains can fall without warning and should always be carefully supported. Roof bolt holes should never be drilled directly in fossil remains, because the vibrations could cause them to be dislodged. 

Once a suspected ore deposit has been found in a certain region, soil samples may be collected in a systematic grid over the area. The soil samples are analyzed for the elements most likely to be present in the potential ore deposit. Areas that have much higher concentrations of these elements may indicate the presence of ore directly below the surlace. Geologists may drill directly into the areas with high concentrations of these elements to obtain subsurfece samples to confirm the kinds of minerals and the elemental concentrations. This method, for example, found zinc deposits near Queensland, Australia. 

Instead of a straw cover the beet can be drilled direct into ploughed and furrow-pressed land. Compaction is avoided and the press helps to stabilise the top few centimetres of the soil. Direct drilling into the undisturbed soil, usually stubble, using precision drills modified for the pmpose, is sometimes used as a technique to prevent blowing. 

Spring greens are mainly drilled direct in August, transplanted in September or direct drilled in April to June at its final crop spacing 38 x 13 cm. 

Faces to be drilled usually required to be perpendicular to the drilling direction unless spot faced, and adequate clearance should be provided for. 

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