The profound connotation of the terminology“oil and gas preservation unit” and the role it plays in oil and gas exploration in marine strata in South China is very important.The paper“Concept of hydrocarbon preservation unit and its appraisal principles”by He Dengfa et al.(2004) has promoted propagation of this concept

but it incorrectly regarded the article by Ma Li et al.(1998) as the first paper putting forward this concept.The concept of“oil and gas preservation unit”and the originality of its connotation should belong to Mr.Li Shangwu and Dianqiangui Petroleum Exploration Bureau

but not to other people or organizations/units.