Abstract: The paper titled "a new method for compaction correction", which was issued on Experimental Petroleum Geology (2000,Vol.22,No.2),has arosed some attention.In order to make the method more clear and more understandable,the related principle,concepts,calculating methods and characteristics of density-depth curves wers explicated.In processing of compaction correction,the paleo-porosity-depth function is not the same of the present porosity depth function,and the density-depth function shows same property.Parameter Δ γ is very important to the mew method for compaction correction,which is based on the principle keeping the formation grain volume and mass constant.