Wells are drilled directionally for several purposes: • Increasing the exposed section length through the reservoir by drilling through the reservoir at an angle.• Drilling into the reservoir where vertical access is difficult or not possible. For instance an oilfield under a town, under a lake, or underneath a difficult-to-drill formation.
[pdf] Sonic drilling employs a high frequency, rotary vibratory drill that is designed to fluidize, overburden, and fracture rock faces. This process results in seamless casing advancement or continuous core samples that can be accessed without the application of drilling fluids.
[pdf] Directional boring costs $10 to $30 per linear foot or $1,000 to $9,000 total on average. Underground directional boring or horizontal directional drilling prices depend on the location and ground conditions.
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