东濮凹陷深层气勘探新思路

东濮凹陷以深层天然气资源丰富而著称，但多年来的数十口深井钻探效果不理想。人们将其原因归结为“储集层物性差”，即便局部存在良好储集层也“难以捉摸”，这是以“深盆气”为模式，以岩性和小构造圈闭为对象进行钻探得出的结论。通过综合研究认为，东濮凹陷的洼陷带中存在规模较大的古构造，圈闭条件好，它们的形成时期与油气生成，运聚时期相匹配，因而较早捕获油气，并使圈闭范围内的储集层保留了较好的原始孔隙，减缓或抑制了

SOME NEW THOUGHTS FOR DEEP NATURAI, GAS EXPLORATION IN DONGPU SAG

Dengpu sag is well known for.its rich deep-lying natural gas resources. Explorations by drilling several dozen deep wells have been done in the past years, but with no satisfactory results. Deep-lying gas is difficult to be handled even in the area with locally better reservoir conditions. People attribute this to the poor physical properties of the reservoir rocks. The above recognition is just based on deep-hasin gas" pattern and drillings of lithological and small structural traps. ln this paper, we discussed the distribution rules of the physical properties of the deep reservoir rocks and got the conclusion that: The paleostructures in the sag are on a large scale with better sealing conditions, which are matched better with the timing for hydrocarbon generation and migration. Since hydrocarbons were captured in early stages, the reservoirs in the trap area had no environment for hydrochemical reaction which would retard and restrain the worsening of physical properties in the later period, and preserved the original better porosities. On the basis of all the above knowledegs, we put forward that the exploration of deep gas in the sag should mainIy be focused on the structural traps, and also point out that faulted zone of the placanticline in the south part of the western sag belt and the Lijia-Linzhai structure group should be the favorable areas for deep gas exploration.