2006-10-02 11:24:56 · 6 answers · asked by colinbrowning 1 in Science & Mathematics ➔ Earth Sciences & Geology
water, gas, or compaction (a new development, pumping in CO2)
2006-10-02 11:37:06 · answer #1 · answered by Robert A 5 · 0⤊ 0⤋
In some cases, water will seep through -- in fact in some oil wells, water is actively pumped under pressure to push the oil out. If water does not replace the oil, then the ground will eventually compact slightly.
2006-10-02 11:30:48 · answer #2 · answered by Vincent G 7 · 1⤊ 0⤋
A point to note is that the oil is not stored in a giant underground reservoir (even if these words are used!). It is absorbed into porous rock. Unlike coal mining, there is little risk of the ground above collapsing as the oil is removed. It's more like a domestic water well, where water from the surrounding soil/rock seeps into a hole drilled into the ground.
2006-10-05 23:42:08 · answer #3 · answered by DriverRob 4 · 0⤊ 0⤋
Usually when oil is formed gas seperates out and forms at the top and increases in pressure as the oil and gas are usually held in an airtight cavern. When we drill down we rupture that cavern hence why oil fountains out in hollywood movies. As the gas is also marketable it is usually syphoned out first and then as a previous answerer noted sea water is pumped in to force the oil out. As we all know oil and water don't mix and water is heavier than oil so sinks to the bottem and forces the oil up.
2006-10-02 22:20:07 · answer #4 · answered by STEVE MACK 2 · 0⤊ 0⤋
Oil is formed by the breakdown of plants over millions of years. It collects in rock basins such as lie under the North Sea. As they pump the oil or bring it up under natural pressure the oil around runs down and replaces it but eventually it runs out and in about 50 to 100 years time it will all be gone
2006-10-02 11:29:43 · answer #5 · answered by Maid Angela 7 · 0⤊ 2⤋
After 50 or 60 years..more oil.
2006-10-02 12:25:25 · answer #6 · answered by Robert Abuse 7 · 0⤊ 2⤋