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1956年,一家大石油公司在米德兰盆地北部构造隆起上钻了一口探测密西西比系的试验井。其主要目的层是致密的密西西比系碳酸盐岩。在钻穿二叠系狼营统期间,7288ft～7320ft井段有两次钻井中断记录。可见到该井段确有油气显示。 1992年,一家独立石油公司重新利用这口井,并用现代测井系列重新测井。上部层段的孔隙度范围为8%～10%,含水饱和度为16%～18%;下部层段孔隙度范围为10%～15%,含水饱和度为9%～11%。这些含水饱和度是假设m=n=2时,用Archie公式计算得到的。根据Asquith(1995年)研究出的用于确定孔隙类型的岩石物性交会图发现,狼营统孔隙发育段的主要孔隙是溶洞孔隙。一系列的岩石物性交会图,包括S_(wa)与S_(wr)和R_l/R_w与R_(SPI)/R等交会图,同产率指数(PRI)图一起表明两段地层都应该有产能。然而,深、浅电阻率孔隙度关系图表明烃的可动性可能很差。在两个孔隙发育段取的5块旋转井壁岩心发现,其孔隙类型为鲕穴孔隙。岩心分析表明孔隙度变化范围为6.9%～13.0%,渗透率为0.02mD～0.01mD。两孔隙发育段的钻杆测试(DST)只回收了69ft钻井泥浆。岩心数据和DST结果都与岩石物性资料一致,表明储层渗透率低导致了油气可动性极差。这口井最终被封堵弃井(P&A)。
In 1956, a large oil company drilled a test well to probe the Mississippi system in the tectonic uplift of northern Midlands. Its main target is a dense Mississippian carbonate rock. During drilling through the Permian wolf camp, there were two records of drilling interruptions in the 7288 ft ~ 7320 ft section. Can be seen that the wells do have oil and gas shows. In 1992, an independent oil company reused the well and re-logged it using modern logging tools. The porosity of the upper interval ranges from 8% to 10% and the water saturation ranges from 16% to 18%. The porosity of the lower interval ranges from 10% to 15% and the water saturation ranges from 9% to 11%. These water saturations are calculated using the Archie formula for m = n = 2. According to the cross-plot of petrophysics used to determine pore types developed by Asquith (1995), it is found that the major pore of the wolf camp pore development zone is the cave porosity. A series of cross-plot maps of petrophysical properties, including crossings of S wa and wr and R_l / R_w and R_sp / R, together with the PRI plots, indicate that both strata should have the capacity . However, the relationship between deep and shallow resistivity porosity shows that hydrocarbon mobility may be poor. The core of five rotating shaft cores taken from the two pore development sections found that the pore type is the ooze hole. Core analysis shows that the porosity ranged from 6.9% to 13.0% and permeability from 0.02mD to 0.01mD. The Drill Pipe Test (DST) of the two-pore development section only recovered 69 ft of drilling mud. Core data and DST results are consistent with petrophysical data, indicating that low reservoir permeability leads to very poor hydrocarbon mobility. The well was finally blocked off P & A.