C/O log, Neutron-life log and Nuclear-magnetism log are familiar method to estimate production layer, but they are only used in some key wells as a result of high cost.

• 常见的产层评价方法有碳氧比测井、中子寿命测井、核磁测井等，但由于成本高只用于部分关键井，取样分析资料是有限的。