新疆04井水位突降异常的机理分析

ANALYSIS ON MECHANISM OF SUDDENLY- LOWERING ANOMALY OF WATER LEVEL OF XINJIANG WELL 04

通过 0 4井地下水动力学条件和地球化学环境的综合分析 ,探讨了井水位突降异常变化的基本特征和相邻两井含水层孔隙压力动态的关系及相互作用过程。 4 b井喷 (溢 )水卸压是 0 4井水位突降的直接原因。当 0 4井的水位升高 ,水头高度达到并超过 4 b井井口的高度时 ,4 b井开始喷水卸压 ,水头损失造成孔隙压力的降低而形成降落漏斗 ,造成 0 4井水位突然下降 ,一旦 4 b井喷水停止 ,0 4井水位又开始上升并逐步恢复到正常水位高度。在 0 4井水位持续突降变化阶段 ,可通过统计突降过程参数 (如突降发生的频度、两次突降异常之间的时长等 )

From June 1992 to the end of Feb.2000, there were 172 suddenly lowering anomalies of water level appearing in Xinjiang Well 04. Combined with the data on ground water dynamic conditions and geological environment at Xinjiang Well 04, the authors studied the basic characteristics of this kind of anomalies and the interaction of aquifer pore pressure between two neighboring wells, Well 04 and Well 4b. It is thought that the water blowing and pressure unloading of Well 4b is the direct reason that cause the level dropping of Well 04. The change of water capacity and structural stress will change the pore pressure of water bearing medium, and which will make the level of Well 04 rise. When the water head is up to or beyond the height of Well 4b, Well 4b will begin to blow and unload pressure. The loss of water pressure makes the pore pressure drop and shapes “cone of influence” of the pressure, thus cause the sudden lower of water level in Well 04. Once Well 4b stops blowing, the level of Well 04 will begin to rise and return to normal. The authors think, even in the period that there is lasting suddenly lowering variation of water level of Well 04, the seismic anomaly can still be determined on the basis of the statistics of suddenly lowering process parameters.