低煤阶 meaning in Chinese

low coal rank

Determination of transmittance for low rank coal
低煤阶煤的透光率测定方法
Experimental study on physical modeling of hydrodynamic condition in low - rank coalbed methane reservoir
低煤阶煤层气藏水动力条件的物理模拟实验
The analysis considered the improvement of the coalbed physical property by heat in structural movements in high coal rank reservoirs and the important role of biogas and free gas in low rank cbm reservoirs
在分析过程中考虑了构造热事件对高煤阶煤层气藏物性的改造作用和生物气、游离气在低煤阶煤层气成藏过程中的作用。
The differences between high and low coal rank reservoirs are analyzed from such aspects as the conditions of the coalbed methane ' s fountain , the coalbed adsorption capacity , the hydrogeologic and physical property of coal beds , and the reservoir forming process
摘要从煤层气成藏的气源条件、煤层的储集能力、煤层的物性、煤层的水文地质条件和成藏过程等方面，分析了高煤阶煤层气和低煤阶煤层气成藏的差异性。