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{{publication  

{{publication  

  | image  = exploring-for-oil-and-gas-traps.png

  | image  = exploring-for-oil-and-gas-traps.png

  | series  = Treatise in Petroleum Geology

  | series  = Treatise in Petroleum Geology

  | title  = Exploring for Oil and Gas Traps

  | title  = Exploring for Oil and Gas Traps

  | isbn    = 0-89181-602-X

  | isbn    = 0-89181-602-X

}}

}}

In exploration, the general question is ''Where can we find substantial quantities of hydrocarbons that are economical to produce?'' To solve this problem, exploration geologists find and evaluate a prospect. In addition to helping evaluate petroleum charge, trap, and timing, the petroleum system concept can help in the exploration process by determining exploration intensity and assessing risk.

In exploration, the general question is ''Where can we find substantial quantities of hydrocarbons that are economical to produce?'' To solve this problem, exploration geologists find and evaluate a prospect. In addition to helping evaluate petroleum charge, trap, and timing, [[the petroleum system concept]] can help in the exploration process by determining exploration intensity and assessing risk.

==Play==

==Play==

==Exploration intensity==

==Exploration intensity==

In a petroleum province, drilling density usually indicates how intensively an area has been explored. Though this is a relative measure, a petroleum province having one exploratory well every square kilometer is well explored compared with a province that has one well every 100 km². Exploration intensity by province ranges from lightly to moderately to heavily explored. However, in a petroleum province with overlapping petroleum systems, the shallowest petroleum system may be heavily explored compared with the deeper petroleum systems. To determine level of exploration, each petroleum system in the province of interest should be mapped and the size and location of the commercial accumulations compared with the dry exploratory wells. The dry-hole ratio or success ratio determines exploration intensity and success.

In a petroleum province, drilling density usually indicates how intensively an area has been explored. Though this is a relative measure, a petroleum province having one exploratory well every square kilometer is well explored compared with a province that has one well every 100 km². Exploration intensity by province ranges from lightly to moderately to heavily explored. However, in a petroleum province with overlapping [[petroleum systems]], the shallowest petroleum system may be heavily explored compared with the deeper petroleum systems. To determine level of exploration, each petroleum system in the province of interest should be mapped and the size and location of the commercial accumulations compared with the dry exploratory wells. The dry-hole ratio or success ratio determines exploration intensity and success.

The graphs in the figure below conceptually summarize the exploration process relative to time. The top graph shows that a frontier petroleum province or petroleum system starts with only prospects (1.00 or 100%); with time, some or all (shown here) of those prospects become oil (gas) fields. The bottom graph shows that the highest percentage of the cumulative petroleum reserves are found early in the exploration process. The quicker we determine the size and extent of a petroleum system, the more likely we will be able to decide whether to continue drilling exploratory wells.

The graphs in the figure below conceptually summarize the exploration process relative to time. The top graph shows that a frontier petroleum province or petroleum system starts with only prospects (1.00 or 100%); with time, some or all (shown here) of those prospects become oil (gas) fields. The bottom graph shows that the highest percentage of the cumulative petroleum reserves are found early in the exploration process. The quicker we determine the size and extent of a petroleum system, the more likely we will be able to decide whether to continue drilling exploratory wells.

[[file:petroleum-systems_fig3-20.png|thumb|{{figure number|3-20}}]]

[[file:petroleum-systems_fig3-20.png|thumb|{{figure number|3-20}}]]

==External links==

==External links==