准东火14井北断块速度分析及正演模型的应用

Velocity Analysis of North Fault block in Well Huo-14 and Application of Its Forward Model in Jundong Field of Junggar Basin

火14井北断块位于准噶尔盆地东部卡拉麦里山前二叠纪平地泉期前陆盆地的深凹陷,现今主体处于石炭系火山岩逆掩推覆体之下。由于断块上覆火山岩高速层呈北厚南薄的楔状展布,复杂的速度变化制约了断块内构造形态的认识。运用正演模型技术,验证了火14井北断裂的可靠性,同时也证实该断块圈闭的可靠性。为了准确刻划断块内部形态,进行了速度谱精细解释,建立了主要目的层平均速度场。通过异常速度分析,提高了速度分析精度,落实了断块内构造形态。

The north fault block in Well Huo-14 is located in deep sag of the Permian foreland basin of Kalamaili foothill in eastern Junggar basin, in which the main body is under the overthrust nappe of Carboniferous volcanic rocks. The overlying strata of volcanic rocks with high velocity spread in wedge shape being thick in north and thin in south, so they assume varied complex velocities that affect proper understanding of its inner structures. The forward model technique is applied to prove the existence of the north fault block and the trap shaped by the fault block. In order to describe the inner configuration accurately, a detailed interpretation has been made of its velocity spectrum, setting up average velocity fields for major strata. The abnormal velocity analysis verifies both the interpretation accuracy and the structural configuration within the fault block.