A comprehensive analysis of hydrocarbon accumulation conditions and typical reservoirs reveals that a large carbonate petroleum province is formed around the Manjiaer depression in the Tarim Basin and it consists of Ordovician non-structural petroleum reservoirs. Multi-type litho-stratigraphic reservoirs are stacked vertically and connected laterally along the paleo-uplift slopes, with a large area. Reservoirs are intensively heterogeneous, extensively developed and distributed in layers along the top of different-scale sequence boundaries. Hydrocarbon phase and physical properties are diverse and the distribution pattern is "lower gas, upper oil". The oil/gas/water output alters greatly and declines quickly, and 20%-30% high-efficiency wells provide more than 70% of the production. The stable paleo-uplift, widely developed heterogeneous reservoir, multi-stages of hydrocarbon accumulation are the basic forming and distribution conditions of the large carbonate petroleum province. The paleo-uplift near the hydrocarbon kitchen is developed stably and controls the reservoir distribution, migration and accumulation. The special characteristics of carbonate reservoirs result in the wide and discontinuous distribution of irregular fracture-cavity hydrocarbon pools. The enrichment of hydrocarbon is controlled by reservoirs, which are the main controlling factors of the formation and distribution of the large petroleum province. Multi-stages of accumulation and adjustment of hydrocarbon are universal and result in the wide distribution and diversity of oil and gas.%成藏地质条件与典型油气藏综合研究表明,塔里木盆地以奥陶系碳酸盐岩非构造油气藏群为主体,形成大面积复合连片的环满加尔碳酸盐岩大油气区.碳酸盐岩大油气区多类型岩性—地层油气藏纵向叠置、横向连片,沿古隆起斜坡广泛分布；储集层非均质强、大面积展布,沿不同级别层序界面近层状分布；油气相态与物性多样,呈“下气上油”的分布特性；碳酸盐岩油气水产出变化大、递减快,20％～30％的高效井支撑70％以上油气产量.稳定的古隆起、广泛发育的非均质储集层与多期成藏等3大要素的配置控制了塔里木盆地碳酸盐岩大油气区的形成与分布.邻近烃源灶的古隆起长期稳定发育,是大油气区储集层发育的地质基础与油气运聚的指向区；储集层特性造成不规则的缝洞型油气藏群大面积断续分布,油气的富集受控于储集层,储集层是大油气区形成与富集的关键；碳酸盐岩多期油气充注与调整具有普遍性,造成含油气的广泛性与油气性质的多样性.
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