CONTROLED DEVELOPMENT AND EXPLORATION

COMBINING SURFACE AND SUB-SURFACE GEOLOGY WITH STATE OF THE ART SEISMIC EVALUATION

The decision to drill a well for oil and/or gas is the culmination of researching and evaluating all available geological and geophysical (seismic) data that points to the probable existences of a sub-surface geological trap containing hydrocarbons (oil & gas). By utilizing all these scientific disciplines the overall reward to risk becomes extremely attractive.

Surface & Sub-Surface Geology - Since the birth of the oil & gas industry in Titusville, PA in the 1860's, the many decades of mapping the Surface features of rock and sedimentary formations has led to many major field discoveries within the US. The art of Sub-Surface geology is that information derived from previously drilled wells and when combined with Surface geology the success factor is enhanced. The old well data gives the geologist/geophysicist measurements of the underlying rock formation as to the electrical, acoustical, attitudes and radioactive nature of each rock strata penetrated by the old well.

Seismic Surveys - This method identifies geological structures by measuring the reflective properties of sound waves to subterranean or sub sea rock strata. An energy source transmits an acoustic energy pulse into the ground sending sound waves downward. Depending upon the geological formations encountered, part of the energy is transmitted to deeper layers, while the remainder is reflected back to the surface. Sensitive receivers called seismometers (land-based) or hydrophones (submerges underwater) receive and record the signals. The information is transmitted, amplified, filtered, digitized and recorded on magnetic tape for interpretation by geoscience's experts.

2-D Seismic - By far the most common seismic method utilized creates a 2 dimentional picture of the underlying rock strata. This picture created by energy reflected from density changes in rock can define potential traps for the accumulation of oil and/or gas.

2-D Picture of Rock Strata

3-D seismic is an indispensable tool in exploring for new discoveries. Geophysicists interpret the seismic data to locate structures that mat contain oil and gas deposits. Reservoir size, shape and depth estimates as well as porosity and fluid content can be derived from results.

Exploratory Drilling

The only way to confirm the presence of hydrocarbons from a promising structure is to drill. These wells are known as "exploration wells' or 'wildcat wells'. Determining the optimum placement of an exploratory well depends upon the characteristics of the underlying geological formations, surface terrain and environmental impact criteria.

Typically, an exploration well takes about one to two months to complete, but drilling to deeper depths may increase drilling time to several months, Tests are conducted to determine the presence and potential volume of hydrocarbons, flow rates, formation pressures and commerciality.

Stepout or Appraisal Wells

If the results from an exploratory well are positive, more wells - called stepout or appraisal wells - are drilled to determine the size and extent of the field. Directional or horizontal drilling may be drilled from the original exploration well to reduce the operation's environmental footprint.

Production Wells

Once a field is determined to be commercially viable, production wells are drilled. The number of wells required to extract the available hydrocarbons varies depending upon the size and geology of the reservoir.