05.07.2009
Manufactured from coal, is a mixture of hydrogen, carbon monoxide, methane and other gases
A working shift for drilling crew or other oilfield workers. Some tours are 8 hours; the three daily tours are called daylight, evening (or afternoon), and graveyard (or morning). 12-hour tours may also be used; they are called simply day tour and night tour.
Total primary energy supply per capita is a common, albeit imperfect, measure of energy efficiency in a country. Total Primary Energy Supply per Capita refers to the Total Primary Energy Supply (TPES) per head of population. The ratio is expressed in tons of oil equivalent (toe) per person. TPES consists of primary energy production adjusted for net trade and stock changes. Production of secondary energy (e.g. oil/coal products, electricity from fossil fuels, etc.) is not included since the “energy equivalent” of the primary fuels used to create the secondary products or electric power has already been counted. TPES is expressed in tons of oil equivalent. > >
The total pore volume per unit volume of rock
Total Petroleum-initially-in-place is that quantity of petroleum which is estimated to exist originally in naturally occurring accumulations (equivalent to total resources)
Total Petroleum-initially-in-place is, therefore, that quantity of petroleum which is estimated, on a given date, to be contained in known accumulations, plus those quantities already produced therefrom, plus those estimated quantities in accumulations yet to be discovered.
Total Petroleum-initially-in-place may be subdivided into Discovered Petroleum-initially-in place and Undiscovered Petroleum-initially-in-place, with Discovered Petroleum-initially-in-place being limited to known accumulations. It is recognized that all Petroleum-initially-in-place quantities may constitute potentially recoverable resources since the estimation of the proportion which may be recoverable can be subject to significant uncertainty and will change with variations in commercial circumstances, technological developments and data availability. A portion of those quantities classified as Unrecoverable may become recoverable resources in the future as commercial circumstances change, technological developments occur, or additional data are acquired additional data are acquired.