复合钻井条件下粉砂岩与盐膏岩的准确识别

Accurately distinguishing siltstone and salt gypsum rock under combination drilling condition

由于复合钻井技术的推广,特别是PDC钻头的应用,给现场地质录井带来了技术挑战,该文针对东濮凹陷油气藏的重要标志层—盐膏岩,在PDC钻头条件下与粉砂岩岩屑不易识别的问题,从PDC钻头的破岩机理、盐膏岩的地质录井特征,以及盐膏岩与粉砂岩的组成成份入手,总结出稀盐酸、稀氢氟酸滴定与烘烤三种不同的粉砂岩与盐膏岩鉴别方法,该方法适用于现场地质录井,为现场地质人员提供了经验。

Combination drilling technology and the application of PDC bit have brought about technical challenge to wellsite geological logging.According to the problem that salt gypsum rock,which is the important reference mark of Dongpu sag reservoir,is difficult to distinguish with siltstone cuttings under PDC drilling condition,the paper from the viewpoint of the rock breaking mechanism of PDC bit,geological logging characteristics of salt gypsum rock and the composition of salt gypsum rock and siltstone,summarized three distinguishing methods: diluted chlorhydric acid titration, diluted hydrofluoric acid titration and baking out.These methods are suitable for wellsite geological logging and provide the experience for wellsite geologists.