【作者】 李海鹏；

【导师】 冯文光； 杨宇；

【作者基本信息】 成都理工大学 ， 油气田开发工程， 2009， 硕士

【摘要】 在油气开发策略上,我国大多数油田采用注水开发方式。目前,我国大多数注水开发油田已经进入高含水阶段。高含水期采油面临着油井产水量大幅度增加、产油量递减、生产成本上升、钻调井和作业措施效果逐步变差的问题,油田后期开采的难度越来越大。围绕油田特高含水期压力下降、含水上升、产量减小、可采储量采出程度高以及开发效果差等主要问题,以分析剩余油分布规律、提出挖潜增产策略为目的,通过油藏工程方法及油藏数值模拟技术研究,提出了一套特高含水期油藏剩余油分布评价的研究思路和方法。本文通过对赵凹区核三段Ⅳ3~1层系地质背景、钻井、测井、生产及开发简况等资料的收集、整理及处理,从单井研究入手,综合运用水驱曲线、产量递减曲线等油藏工程方法和油藏数值模拟技术,研究特高含水期剩余油分布规律。通过井网适应性评价,结合油藏剩余油的分布特征,提出了特高含水期油田剩余油挖潜措施及方法优选。首先赵凹油田储层属于近物源陡坡型扇三角洲沉积,通过渗透率的差异情况和隔夹层的发育情况,研究完成了储层的非均质性评价,结果表明储层层间和平面非均质性严重,而层内非均质性相对较弱;接着通过耗水率等水驱效果评价指标建立了边水油田特高含水期开发效果评价体系,认为Ⅳ3~1油藏目前注水效果变差,要保证开发效果必须做好稳油控水工作。利用童氏图版法、水驱曲线及广义水驱曲线法和递减曲线法等建立了Ⅳ3~1层系的可采储量标定体系,综合评价认为标定最终采收率结果真实可信。又分别通过产量递减曲线及水驱曲线、相渗曲线分析研究了Ⅳ3~1层系的含水上升规律,与实际生产过程中的含水变化规律对比基本一致;在建立核三段Ⅳ3~1层系的数值模拟模型时,考虑到由实验室实测求取的油水相渗曲线,受岩心非均质性、润湿性和流体饱和历史等的影响而不具有代表性;而生产数据能综合反映油藏及水驱油过程的复杂性,故本次研究使用了利用水驱特征曲线计算相对渗透率曲线的方法,并将计算结果首先应用于上述利用相渗曲线预测含水上升规律的研究,使预测结果与实际情况更加相符;进一步又将该计算结果应用于本次数模研究,对油藏原始地质储量,平均地层压力,日产油,综合含水率等开发指标进行了拟合,拟合效果好,整体拟合误差小于7.5%,单井拟合符合率达84%,表明该油藏数值模拟模型能反映实际油藏状况,模拟剩余油分布可靠,可以作为预测的基本模型。同时在研究剩余油的分布规律时,按小层划分为强、中、弱不同的水淹区域进行分析,结果表明Ⅳ3~1层系受沉积相、储层非均质性、原始油分布特征和井网条件的影响,剩余油主要呈零散分布,D1-D3小层水淹严重,剩余储量少,D4-D7四个小层砂体发育范围小,平面水淹程度和水淹范围也随之减小,剩余油储量相对较大。最后通过对核三段Ⅳ3~1层系井网适应性进行分析,认为目前井网基本达到了经济合理井网密度;但由于油砂体分布系数小,导致采油井单向受效井层多,主力油层水驱程度高,而非主力油层水驱控制程度相对较低,压力场注入能力、产液量不合理,井间存在窜流,注水效果差的情况;结合剩余油的影响因素,综合对核三段Ⅳ3~1油藏剩余油分布特点的认识,提出了剩余油挖潜方法及建议,并设计了3个开发方案,在对该3个方案进行优选后,最终确定方案3为最优方案。课题研究与生产实践紧密结合,将研究成果及时应用于生产实践,在赵凹油田核三段Ⅳ3~1油藏起到了很好的稳油控水效果,为同类油藏开发调整及措施挖潜提供了成功实例。更多还原

【Abstract】 On the strategy of the exploration, most of oil field in china use the methods of water flood. At present,most of oil field in china using waterflood development at high water-cut period.Oil recovery at high water-cut period encountered many troubles such as water production rising greatly, oil production declining, production cost rising, drill or readjust well and development effect deteriorated.Exploitation become difficult at the late stage of oil field development.The pressure and production decline, water cut and degree of reserve recovery is high, and effect of development change into bad at extra high-water cut period. In order to analyze the remainling oil distribution and pull out stimulation of further exploitation,through reservoir engineering and the fine reservoir numerical simulation, some important thinkings and methods of remainling oil distribution were elicited.This text through collecting the materials of geology background, drilling,logging and production,start from studying the single well reservoir, a combined application of reservoir engineering and the fine reservoir numerical simulation is applied to study the distribution of the remaining oil. Through analysing the well pattern and the character of remaining oil distribution, a measurement of further exploitation for oil reservoir at extra-high water-cut period has been put forward and optimized.First, the evaluation on heterogeneity of zhao ao oil-field reservoir which is a steep slope fan delta sedimentary has been completed by studying on permeability contrast and interbed development.The results showed that interlayer heterogeneity and plane heterogeneity of this reservoir were stronger than its in-layer heterogeneity.And then,development effect evaluation system in ultra-high water cut period of edge water reservoir was established by using a series of evaluating indexes about waterflooding effect, for instance water consumption rate and so on. It is suggested that the effect of development of IV31 reservoir is getting worse, so stabilizing oil production and controlling water cut should be done in order to ensure development effect.Calibration system on recoverable reserves of IV31 layer series was established by using Tong’s chart method,water drive curves,generalized water drive curve method,production decline curve method and so on. Conclusively, it is suggested that the calibration results of ultimate recovery are believable.At last,accoding to production decline curves,water drive curves and relative permeability curves, analysis and study on incremental rules of water cut of IV31 layer series was carried out,which is basically identical to incremental rules of water cut in practical production process.Because the relative permeability measured in the lab doesn’t have representativeness as the homogeneity,wettability of the core and the time of the core saturated, however, the performance data could comprehensively reflect the reservoir and the process of the displacement of oil by water, the author calculated the permeability ratio curve by using the water driving characteristic curve during this research. And first taking the calculated result into the forcasting of the water ascending law, and the result is accordant to the actual situation.Then taking the result into the numerical simulation, and have matched the original geologic reserve, the average reservoir pressure,the daily oil production and the composite water cut,the effectiveness of the application is satisfied.The entire fit error is smaller than 7.5 percents,and the single well matching coincidence rate is 84 percents.At the same time,when studying the regular pattern of remainling oil distribution, the author according to the level of water out, divide three different areas. And the result indicate that because of the precipitation facie,the aeolotropism of reservoir,the distribution of original oil and the feature of well pattern,the remainling oil distribute straily. Subzone D1 to D3 flooding seriously,the remaining reserves is little;The sand body morphology of subzone D4 to D7 is small,and flooding softly,so the remaining reserves is high.At last,the author through analysing the well pattern account that now the well pattern is the economic rational well spacing density;But because the distribution factor of the reservoir sand is small,so the waterflood efficiency of the major reservoir is high,and opposite the non-major reservoir is low. The injection capacity and the well fluid is inconsistency,the flood effectiveness is bad.Associate with the affecting factor of the remaining oil and the pattern of the remaining oil,the author proposed some methods about the further exploitation of remainling oil,and at the same time designed three development plans.Passed ingoing analysis and optimize, finally we have choosed the third plan as the best plan.Through comprehensive evaluation we realizing that the combination of research and practice, put outcome of investigation into practice of production can make a good effect to freeze the production of oil and decrease the water-cut. This set a good model for the production of same type reservoir.更多还原