| 摘要 |
<p>The permeability of a siliceous formation is increased by injecting in sequence, a fluoboric acid solution followed by a mud acid (HCI/HF) solution. The method is particularly advantageous in formations which have a tendency to plug initially upon contact with mud acid, or with HCl commonly used as a preflush ahead of mud acid. When contacted initially with fluoboric acid, such formations show little or no plugging effects when subsequently treated with mud acid.</p> |
