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在对生、运、储、聚(圈)、散(盖、保)诸成藏要素与天然气富集关系剖析的基础上指出，天然气的生成和保存条件是决定其可能的富集规模和分布规律的全局性、战略性的制约因素，即生成、保存条件越好的盆地或地区，天然气富集的程度将越高。而运移、储集和圈闭条件虽然是天然气成藏至关重要、甚至是必不可少的成藏要素，但它们主要是决定气田(藏)的具体位置及最大的可能规模，因此，可视为是局域性和战术性的从属要素。对天然气富集主控因素的这一认识，将有助于结合含气区或含气盆地天然气的生成和保存条件，从宏观上评价天然气的有利探区和大中型气田的有利勘探方向。

Analysis of the Main Control Factors of Natural Gas Enrichment

Based on analysing the relationship between natural gas enrichment and the factors related to the formation of natural gas pools,such as generation,migration,reservoir,accumulation (trap) and preservation of natural gas,it is pointed out that the conditions of gas generation and preservation are the main control factors determining the enrichment scale and distribution regularity of natural gas on the whole,which means the better the conditions of gas generation and reservation are,the higher the degree of gas enrichment is.Although the conditions of migration,accumulation and trap are essential,or evenabsolutely necessary,for the formation of gas pool,they mainly determine the concrete location and the possible maximum scale of gas field or gas pool.Therefore,they can be regarded as local and tactical assistant factors.The cognition for the main control factors of gas enrichment will redound to evaluating the favorable exploration regions of natural gas and the favorable exploration direction for large and middle size gas fields,if combining with the conditions of gas generation and preservation for a given gas bearing region or a basin.