| 摘要 |
<p>Temporary blockage of fractures in the walls of a borehole at the lvel of a geological formation by injecting a suspension of a solid powdered, blocking agent in a carrier liquid, the blocking agent having a m.p. below the geo-temp. of the formation to be sealed off, or the equilibrium temp. of the formation established after the closure of the wall, and by carrying out the following successive operations:- (a) injection of a fluid refrigerant into the formation to lower its temp. to a value below the m.p. of the blocking agent, (b) injection of the carrier fluid/blocking agent mixture whereby the blocking agent totally seals off the fractures and is finely eliminated from it in contact with the carrier fluid by softening and then fusion when the formation heats up again and regains a temp. at least equal to the m.p. of the blocking agent. A prefd. blocking agent may include >=1 wax.</p> |
