文章采用激光剥蚀-电感耦合等离子质谱仪(laser ablation inductively coupled plasma mass spectrometry,LA-ICP-MS)方法对苏北盆地高邮凹陷新生代辉绿岩4个样品进行锆石U-Pb年代学研究,获得的岩浆结晶年龄分别为(45.3±1.3)、(59.8±1.7)、(40.5±0.7)、(44.8±1.1) Ma,指示其形成时代为古新世和始新世,表明苏北盆地岩浆活动具有多期性的特点.苏北盆地在新生代时期的发育过程受郯庐断裂带及太平洋板块俯冲后撤的影响,总体上处于太平洋板块俯冲后撤形成的弧后拉张环境,其中早期岩浆活动明显受郯庐断裂带伸展活动的控制.锆石UPb年代学特征显示,在吴堡期2套辉绿岩就已经开始上升侵位,而并非是相关文献中的三垛期.此次工作获得的锆石年龄多集中于40.5～45.3 Ma,而其北西侧的渤海湾盆地新生代锆石年龄多集中于60～50 Ma,造成该现象的原因可能是太平洋板块俯冲后撤引起的弧后伸展区域变迁.

The shale from the Cretaceous Taizhou Formation is an important source rock in the Gaoyou Sag, Northern Jiangsu Basin. Fifty-three shale core samples analyzed for total organic carbon (TOC) and Rock-Eval pyrolysis analyses were used to evaluate the geochemistry of this shale. Twenty-one samples of them were analyzed using solvent extraction, extract fractionation, Gas Chromatography-Mass Spectrometer (GC-MS) of the saturated fraction, and organic petrology analyses. Based on the test results, the shale of the Taizhou Formation contains mainly Type II-III organic matter and is chiefly oil-prone and oil-gas-prone, as a fair to good oil-source rock with a small quantity of gas-source rock. Vitrinite reflectance, Rock-Eval pyrolysis, and biomarker suggest that in this sag, the shale of the Taizhou Formation is mainly in the early mature stage and within the oil window, so the shale generates chiefly liquid oil. The Gaoyou Sag is an oil-generating sag. The saturated fraction and biomarker composition of the shale provide evidence that the Taizhou Formation shale was formed mainly in a reductive sedimentary environment with anoxic fresh to low salinity water. The organic matter came chiefly from plankton and partly from land plants and bacterial organisms.

运用微量元素、X-衍射、岩石薄片分析和岩心观察描述等方法,开展伦坡拉盆地古近系沉积地球化学特征、岩石矿物特征和沉积相类型、沉积演化、沉积模式研究,分析湖盆咸化的沉积响应特征,研究认为:伦坡拉盆地古近系具有环境封闭、持续蒸发咸化的沉积水介质环境,导致盆地内形成大量的碳酸盐岩,并具有陆源碎屑与碳酸盐组份混合的岩石矿物特征.盆地周围受陆源淡水沉积体系控制,发育近源、延伸距离短、相带变化频繁的扇三角洲沉积;湖盆中央受半咸化-咸化水体的控制,发育湖相泥质岩、云坪、混合坪等弱水动力、细粒相带沉积类型;不同时期咸化程度不同,咸化程度越高,陆源体系对盆内沉积的影响越弱.

System comparative studys of the distributions and compositions of light hydrocarbons in crude oils from No.1 area and adjacent oilfields in Junggar basin show that abundant methyl cyclichexane exists in the crude oils with methyl cyclichexane index（MCHI） more than 50% and higher Pr/Ph ratio,which are very different from crude oils from Shixi and Mobei oilfields.This implies that terrestrial matter from higher plants plays a significant role during the generation of the crude oils from No.1 area,and it is consistent with the results of the literature by geochemistry methods of biomarkers and carbon isotope.According to the relationship between the 2,4-DMC5/2,3-DMC5 ratio and the temperature of oil generation,it suggests that the maturity of crude oils from No.1 area is higher than those from Shixi and Mobei oilfields,indicating higher maturity of the organic matter in main source rocks of central Junggar basin.Therefore,it′s very useful of the light hydrocarbon from crude oils for the study of its origin,causes and maturity.

In consideration of the characters of plane changes in structural-lithologic reservoirs and glutenite interbed of upper Tertiary of Dainan Formation in SB Oilfield of Gaoyou Sag of Subei Basin,which was controlled by fan-delta facies,the technical method and process of logging constraint inversion are established for 2nd member of Dainan Formation,including logging curve preprocessing,well-seismic calibration,wavelet extraction,low-frequency model establishment,and key parameter testing etc.It is found out through practical petroleum exploration that log constraint inversion is a useful method to reservoir quantitative prediction and description and it provides precise evidence for predicting the reservoir distribution and better exploration results are obtained in the studied area.

Gaoyou Sag is the area with the highest degree exploration and the greatest oil potential in Subei Basin.In order to reveal the key role of fault acting as vertical migration pathway or lateral sealing in hydrocarbon accumulation and distribution,the characteristics of fault sealing were comprehensively analyzed with the methods of lithology juxtaposition and shale smear in this paper.Result shows that lithology juxtaposition is the critical factor of fault sealing in the case of thick regional cap rock and large fault throw available.But when lithology juxtaposition does not match excellently,shale smear directly decides the fault lateral sealing.The quantitative estimation shows that the lower limit of shale gouge ratio(SGR) is more than 0.65 and fault has sealing capability which is in proportion to SGR.

Zhenwu oilfield,located at the mid-southern part of Gaoyou Sag of Subei basin,is the largest oil field that has been discovered in Subei basin,which has the characteristics of developed long,large oil-bearing area and high enriching-oil degree.The oilfield is located at the downthrow block of Zhen 2 fault in the southern part of the deep sag,and it is to hydrocarbon generating sags.The oil mainly distributes in three layers including the first member of the Sanduo Formation,the first second member of the Dainan Formation.Some petroleum also distributed in the first member of the Funing Formation.Reservoir rocks are mostly fine sandstone and anisometric sandstone.Combining with various geological features,the authors analyse accumulation period and the dynamic accumulation process of Zhenwu oil field by ways of structural evolution,crude oil features and fluid inclusion.The structural evolution history shows that fault activity is strong from Dainan Formation deposition to early Yancheng Deposition.Earth crust uplifted and formation eroded resulted in serious destruction of oil reservoir at the late of Sanduo Formation,then fault continued activity and petroleum migration.The sag continued to accept deposition and fault activity stops at the late of Yancheng Formation deposition,and the petroleum migration rate slowed down.It is favorable for petroleum reservation when the formation thickness was big at the late deposition.From the source rock evolution history ,there are two times of petroleum generation during which the source rock of the second member of the Funing Formation enter the sag is at a great quantity of petroleum generation at the late and last stage of Sanduo Formation when the source rock of the fourth member of the Funing Formation had not reached oil threshold and only generated a little petroleum,so it was the oil mainly generated by the source rock of the second member of the Funing Formation.But most of the reservoirs were damaged by the influence of the regional tectonic activities at the late of Sanduo period.When the Yancheng Formation was depositing,the source rock of second fourth member of the Funing Formation again reached maturation which result in secondary hydrocarbon generation.Meantime,the characteristics of fluid inclusions in Zhenwu oil field show that it mainly developed one phase of fluid inclusion which organic inclusion and its associated brine inclusion mostly develop at the quartz secondary outgrowth cementation and there is only one peak temperature area.Associated with burial history of individual well,the authors find that the time of petroleum migration and accumulation was the time of the second member of Sanduo Formation deposition which had a certain difference with accumulation time inverted by structural evolution and source rock evolution.At last,with the analysis of petroleum dynamic accumulation process by ways of accumulation periods,the authors reach conclusion that there were two accumulation periods in Zhenwu oilfield,firstly,the second member of the Funing Formation generated,migrated and accumulated before the late of Sanduo Formation,but the next structural uplift at the late of Sanduo Formation damaged the early oil reservoirs.At the Early-Middle of Yancheng Formation,it mainly is the time of the fourth member of the Funing Formation reburied and secondary oil generation,which is the essential period of petroleum migration and accumulation.From the the late of Yancheng Formation on,it is the essential period of petroleum preservation.

Gaoyou Depression was an important oil-bearing area in Subei Basin.There faults were developed,the oil distribution of the Eocene epoch had obvious zoning characteristics in each area,the difference in fault activity ratios(FAR) was important for Eocene oil migration and accumulation.Through modeling the history of oil-generation for the source rock and studying the history of the oil filling,the major hydrocarbon filling stages for Eocene reservoirs were determined.In addition,the control function of faults in different areas on Eocene hydrocarbon accumulation was integrally analyzed at the major hydrocarbon filling stage by using faulting activity ratios(FAR).Studies show that the oils in the deep-sag are generally distributed near weak active faults(FARs 10m/Ma),while intense activity fault surfaces(FARs25m/Ma)is the beneficial petroleum migration area,which is non-beneficial for hydrocarbon accumulation.At the same time,the fault activities are lower in the northern slope(FARs5m/Ma),which are not good for oil migration upward along the fault surfaces linearly.Therefore,oil in this area can only migrate upward spirally by the effective collocation of faults and sands,and then accumulate in the Eocene traps.

介绍了江苏油田复杂小断块油气藏滚动勘探开发一体化工作流程形成的思路、特点及相应的关键技术,同时还对该套技术的应用效果进行了分析