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根据埋藏史、热史恢复，运用有机地球化学指标和稳定碳同位素比值，判断出莺－琼盆地 ＹＡ１３－１气田天然气的母质来自于以Ⅲ型干酪根为主的崖城－陵水组。有两个来源：一个是琼东南盆地崖南凹陷埋深在４４５０ｍ以下的烃源岩，另一个是莺歌海盆地埋深在４７００ｍ以下的烃源岩。通过流体包裹体分析，确定出天然气以水溶相在５．８～２．０Ｍａ和２．０Ｍａ至现在期间发生两次高峰运聚。梅山组碳酸盐岩和钙质泥岩具７～１０ＭＰａ的排替压力并发育有４９～６６ＭＰａ的异常超压，从而成为其有效盖层。陵水组储层因浅埋时间长，受大气淡水淋滤作用和有机酸对铝硅盐骨架颗粒和碳酸盐胶结物的溶解／沉淀，在后来的深埋过程中仍然保持平均１４，９％的孔隙率和２１３ｘ１０~（－３）μｍ~２的渗透率，披覆背斜的ＹＡ１３－１圈闭形成于１０．５Ｍａ，远远早于天然气的运聚时间。从而在生、运、聚、保和圈闭、储－盖层演化诸方面奠定了在ＹＡ１３－１地区形成我国迄今最大气田的必要条件。
According to burial history, thermal history restoration, using organic geochemical indicators and stable carbon isotope ratios, it is concluded that the parent material of YA13-1 gas field in Ying-Qiong Basin comes from Yacheng-Lingshui Formation, which is mainly Type III kerogen. There are two sources: one is a source rock buried below 4450m in the Yalong Sag, Qiongdongnan Basin, and the other is a source rock buried below 4700m in the Yinggehai Basin. Based on the analysis of fluid inclusions, it is confirmed that there are two peak transport and accumulation of natural gas in aqueous phase between 5.8 ~ 2.0Ma and 2.0Ma up to now. Meishan Formation carbonate rocks and calcareous mudstones with 7 ~ 10MPa displacement pressure and the development of 49 ~ 66MPa abnormal overpressure, which became effective cover. The reservoir of Lingshui Formation was still leveled off by the leaching of atmospheric freshwater and the dissolution / precipitation of organic acid on Al-Si-S framework particles and carbonate cements due to the shallow covering time. % Porosity and a permeability of 213x10 ~ (-3) μm ~ 2. The YA13-1 trapping trap was formed at 10.5Ma, much earlier than the natural gas migration and accumulation time. Thus laying the necessary conditions for the formation of the largest gas field in China so far in YA13-1 in terms of birth, transport, polygamy, preservation and trapping, and the evolution of the reservoir-cap rock.