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尼日尔三角洲盆地的石油储量资料呈现出一种具有坡折的双峰对数正态分布,它反映出勘探程度的变化、远景的好坏和大油田的分布。有几个异常储量区是以20万桶/平方公里的临界石油储量密度选定值圈定的。这里的五个主要高产中心(储量衬度>3)呈弧形带(高产带)状排列。这条弧形带与现在的海岸线位置相一致。这条高产带是洋壳和大陆壳之间的过渡带,亦是一条以构造活动性递增为特点的薄弱地带。在尼日尔三角洲体系穿过该带期间,它主要是一建设性的三角洲体系和至少由五个现在圈定为高产中心的复合三角洲组成。在高产带以外破坏作用为主的地方可导致复合三角洲的消失。在这些地区内,主要储量集中带的分布范围是受迭复在生长断层活动区上的支叉河道迁移和伸展控制的。高产带和岸外带与形成三角洲中心地热最小值的高地热带相合。这种相合性再加上沉积物自北向南时代逐渐变新,表明每单位深度的成熟度在岸外带和中心三角洲鼻部比高产带要低。这表明,岸外带和中心三角洲鼻部与高产带相比,前者碳氢化合物层位较深且量少,而后者相反。这些因素和勘探的深度较浅可能是造成目前高产带南部缺乏高产中心的原因。
The Niger Delta Basin oil reserves data show a bimodal lognormal distribution with slope break, which reflects changes in exploration level, long-term prospects and the distribution of large oil fields. There are several anomalous reserves that are delineated by the selected value of the critical oil reserve density of 200,000 bbls / km2. The five major high-yield centers here (reserves contrast> 3) are arcuate bands (high-yield bands). This arc is consistent with the current coastline. This high-yield zone is a transition zone between the oceanic crust and the continental crust. It is also a weak zone characterized by tectonic activity. During the passage of the Niger Delta system through the belt, it consisted mainly of a constructive delta system and a composite delta of at least five now delineated as high-yield centers. Where the damaging effects outside the high-yield zone dominate can lead to the disappearance of compound deltas. Within these areas, the distribution of major reserve belts is governed by the migration and extension of the tributary channels overlaying the active area of the growing fault. The high-yielding belt and offshore belt coincide with the high geothermal zone that forms the minimum geothermal heat in the center of the delta. This consistency, combined with the gradual change of sediments from north to south, indicates that the maturity per unit depth is lower in the offshore zone and in the central delta nose than in the high-yield zone. This indicates that the former has a deeper and lower hydrocarbon layer than the high-yield zone in the offshore zone and the central delta, while the latter is opposite. The shallowness of these factors and exploration can be responsible for the current lack of productive centers in the southern high yield zone.