Geophysics
Exploration Geophysicists use geophysics to find oil and gas, where drilling rig, production platform, seismic ship are in background. A lot of preparation is required to get the energy source, recording devices, recording truck, trace the path of the energy, some reflected, some transmitted. In previous generations, they used to have wide, high-impact cut lines, Today, in environmentally sensitive areas, hand cut, low-impact cut lines are used; supported by helicopters, and hence not as much heavy equipment.
The NoDoC Cost Models offer cost data for estimating this aspect of the exploration process. The models use probability functions for estimation. Proven reserves exist where there is a sufficient body of supporting data from geology, geophysics, well tests, and field production to estimate the extent of the oil or gas contained in the body of rock. They are deemed, “commercially recoverable, from a given date forward, from known reservoirs and under current economic conditions, operating methods, and government regulations.” Proven reserves can be developed or undeveloped. Probable reserves are unproven reserves, but geological and engineering data suggest that they are more likely than not to be recoverable. Statistical methods are often used in the calculation of probable reserves, and the deciding criterion is usually that there should be at least a 50% probability that the quantities actually recovered will “equal or exceed the sum of estimated proved plus probable reserves.” Probable reserves can be in areas adjoining proven or developed fields or isolated from developed fields, but with drilling and testing data that indicates they are economic with current technology. Possible reserves are unproved reserves that are less likely to be recoverable than probable reserves, based on geological and engineering data analysis. Statistically, they are defined as reserves that, if recovered, have – at most – a 10% probability of equalling or exceeding the sum of the estimated proven, probable, and possible reserves. Possible reserves have few, if any, wells drilled; and the reservoir has not been produced, or even tested. However, the reservoir displays favourable geology and geophysics, and its size is estimated by statistical analysis. Possible reserves can also be in areas with good data to indicate that oil and gas are present, but they may not be commercially developable, or the technology to develop them may not exist (but such technology improvements can reasonably be expected in the future). Although this sounds very speculative, there is such a long history of oil and gas production that these estimates are regarded with a fair degree of confidence.
The NoDoC Cost Models offer cost data for estimating this aspect of the exploration process. The models use probability functions for estimation. Proven reserves exist where there is a sufficient body of supporting data from geology, geophysics, well tests, and field production to estimate the extent of the oil or gas contained in the body of rock. They are deemed, “commercially recoverable, from a given date forward, from known reservoirs and under current economic conditions, operating methods, and government regulations.” Proven reserves can be developed or undeveloped. Probable reserves are unproven reserves, but geological and engineering data suggest that they are more likely than not to be recoverable. Statistical methods are often used in the calculation of probable reserves, and the deciding criterion is usually that there should be at least a 50% probability that the quantities actually recovered will “equal or exceed the sum of estimated proved plus probable reserves.” Probable reserves can be in areas adjoining proven or developed fields or isolated from developed fields, but with drilling and testing data that indicates they are economic with current technology. Possible reserves are unproved reserves that are less likely to be recoverable than probable reserves, based on geological and engineering data analysis. Statistically, they are defined as reserves that, if recovered, have – at most – a 10% probability of equalling or exceeding the sum of the estimated proven, probable, and possible reserves. Possible reserves have few, if any, wells drilled; and the reservoir has not been produced, or even tested. However, the reservoir displays favourable geology and geophysics, and its size is estimated by statistical analysis. Possible reserves can also be in areas with good data to indicate that oil and gas are present, but they may not be commercially developable, or the technology to develop them may not exist (but such technology improvements can reasonably be expected in the future). Although this sounds very speculative, there is such a long history of oil and gas production that these estimates are regarded with a fair degree of confidence.
