共查询到20条相似文献，搜索用时 15 毫秒
1.
Baisakhi Das Rima Chatterjee Dip Kumar Singha Rajan Kumar 《Journal of the Geological Society of India》2017,90(1):32-40
Seismic attributes such as: amplitude envelope, instantaneous phase and cosine of instantaneous phase of 2D post-stack seismic data facilitates structural and stratigraphic interpretation of shallow marine offshore, Krishna-Godavari basin. Two seismic sections namely, X and Y oriented N-S passing through wells W-1 andW-2 respectively are considered for seismic attribute analysis and porosity prediction. The gamma ray log trend indicates deposition of cleaning upward sediment. Coarsening upward, clayey-silty-sandy bodies, making a series of about 50-60 m thickness, have been evidenced from the gamma ray log. An extensional structural style comprising growth faults is associated with the progradational style of deposition. Four seismic zones have been distinguished. These zones differ in amplitude, frequency and continuity of the reflectors. Channel sands of Cretaceous age of Raghavapuram shale are identified in well log, seismic section and its acoustic impedance section. Major stratigraphic horizons along with faults extending to basement are marked with the help of attribute analysis. Porosity is mapped from transformation of acoustic impedance. The shales/unconsolidated sediments measure a high porosity with low impedance and the more porous sands are in an intermediate range. The predicted impedance and porosity values may be erroneous beyond the drilled depth because of non availability of well log data for calibration. 相似文献
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在二维地震区、井控程度低及曲流河三角洲前缘沉积等复杂岩性储层中,实施水平井储层钻遇率较低。三维地质模型迭代更新与地质–工程一体化相结合的水平井地质导向技术应用逐渐广泛。鄂尔多斯盆地东南缘上古生界煤系发育山西组山2 3亚段北岔沟砂岩等多套致密砂岩储层,其中,大宁–吉县区块砂岩层厚度较薄、纵向岩性复杂、横向变化快、微幅构造发育,基本无出发井且末端井较远(大于1 500 m),水平井导向难度大。为了提高低勘探程度区水平井钻探效果,通过标志层识别与厘定、煤岩层对比、资料精准分析与补充、储层顶底特征识别等方法开展研究。首先,总结研究区煤层与炭质泥岩的快速区分方法,解决现场岩性识别困难的难题,构建研究区地层格架;而后,基于测井、地震、地质多种资料的地层精细对比,厘定1个Ⅰ级标志层及3个Ⅱ级标志层,在山2 3亚段进一步确定2个Ⅱ级标志层。最后,提出着陆点控制技术、水平段钻遇率提高技术与钻头出层判断方法,形成了三角洲前缘亚相储层水平井地质导向技术。将该技术应用于DJ-P37井区,累计完钻34口,平均砂岩钻遇率78.30%,取得了良好的钻探效果,可为类似区域煤系水平井钻进提供技术借鉴。 相似文献
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Wellbore attributes (i.e., deviation, casings and plugging characteristics) for 85 wells in the St. Lawrence Lowlands basin of southern Quebec were compiled from drilling reports and abandonment programs to provide an overview of the abandoned well characteristics and to establish a diagnosis on the long-term reliability of the completion and abandonment practices carried out by the companies since the beginning of oil and gas exploration. Using these data, the conventional and unconventional wells were divided into four categories: (1) conventional wells drilled before 1950, (2) conventional wells drilled between 1950 and 1970, (3) conventional wells drilled after 1970 and shale gas wells (all drilled after 2000). Very little information was available for wells drilled before 1950. More information was available for the wells drilled from 1950 to 1970 which is considered a transition period between old and modern technology. Conventional and unconventional wells drilled after 1970 were generally well documented and their attributes corresponded to API standards. A decision tree, inspired from the methodology proposed by Watson and Bachu (SPE Drill Complet 24(1):115–126, 2009. https://doi.org/10.2118/106817-PA), was then created to assess the potential of leakage of each of the conventional and unconventional wells using the compiled attributes. The factors defining the probability of well leakage were wellbore deviation, height of cement in casing annuli (partially or fully cemented), type of abandonment plugs (cement or mechanical plugs) and drilling date (before or after 1970). Among the 85 wells assessed by this tree, the probability of leakage was higher than 50% for 55 wells (65% of wells). Wellbore deviation and lack of information on the construction and abandonment methods were respectively the primary and secondary causes of high probability of leakage of these wells. 相似文献
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【研究目的】陆相页岩油是中国能源重要的接替领域,长水平井精确钻探是实现页岩油商业开发的关键技术。但由于陆相页岩具有黏土矿物含量高、非均质性强、层理发育等特点,导致水平井井壁失稳严重、薄目标靶层精确导向困难等钻探技术难题。【研究方法】以松辽盆地南部青一段页岩为研究对象,综合利用地球化学、地球物理、岩石力学、地应力分析等手段,开展地质工程一体化研究。【研究结果】青一段上部页岩为层理型页岩不适合作为水平井穿行层段,青一段中下部纹层状页岩中的含油薄砂条兼具含油性、可钻性、可压性,可作为穿行目标层;页岩地层需选择强抑制KCL聚胺钻井液体系和油基钻井液体系实施水平井钻探,泥浆密度窗口随水平应力差和井轨迹倾角的增大而增高;测井GR和录井总烃可以精确反映目标靶层岩性非均质变化,结合高精度地球物理,可实时精确调控钻井轨迹。【结论】经应用实践,吉页油1HF井沿1.94m超薄目标靶层安全钻进1252m,钻遇率100%,实现了陆相页岩油长水平段精确钻探的技术突破,为吉页油1HF井获得高产工业油流奠定了基础,对中国同类型陆相页岩油长水平段精确钻探具有引领和借鉴意义。 相似文献
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横观各向同性水敏性地层斜井眼坍塌压力确定 总被引：1，自引：0，他引：1
在以泥页岩为目标储层的非常规油气藏水平井开发中, 钻遇井壁的稳定性问题突出, 一方面是由于在设计钻井液密度时简单采用各向同性介质模型和Mohr-Coulomb强度准则, 另一方面则是由于选用的钻井液性能欠佳, 难以保证建井全过程的井壁稳定。为此, 将地层视为横观各向同性介质, 采用Mogi-Coulomb强度准则判别岩石基体和层理面的稳定性, 同时考虑泥页岩水化作用对岩石力学强度参数的影响, 建立了水敏性地层井壁稳定分析模型, 分析了坍塌压力随井斜、方位、钻井液性能、钻井时间等因素的变化规律。研究结果表明:对于具有显著层理面结构的泥页岩地层, 采用横观各向同性模型比各向同性介质模型更能描述强度的各向异性;采用Mogi-Coulomb准则比Mohr-Coulomb强度准则得到的坍塌压力值与实际吻合程度更高, 在保证井壁稳定的前提下有利于降低钻井液密度, 实现钻井提速;提高钻井液封堵能力、减小泥页岩吸水扩散能力, 有利于延长坍塌周期。利用东濮、威远、焦石坝等工区多口页岩气水平井的实钻资料对本文方法进行了验证, 证实本文方法确定的钻井液密度窗口下值更能满足安全钻井需求。 相似文献
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Haris Ahmed KHAN Ali Asghar SHAHID Muhammad Jahangir KHAN Taher ZOUAGHI Maria Dolores ALVAREZ Syed Danial Mehdi NAQVI 《《地质学报》英文版》2023,97(1):256-268
This research is focused on the analysis of the sequence stratigraphic units of F3 Block, within a wave-dominated delta of Plio–Pleistocene age. Three wells of F3 block and a 3D seismic data, are utilized in this research. The conventional techniques of 3D seismic interpretation were utilized to mark the 11 surfaces on the seismic section. Integration of seismic sequence stratigraphic interpretation, using well logs, and subsequent 3D geostatistical modeling, using seismic data, aided to evaluat... 相似文献
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潘庄地区煤层气U型水平井技术工艺研究 总被引：2，自引：0，他引：2
我国已在多个地区进行了20余口煤层气U型水平井施工,但总体尚处于勘探实验阶段。为了研究潘庄地区煤层气U型水平井施工技术工艺,以寺河井田西区煤层气U型水平井为例,分析了实验区地质条件的可行性,重点研究了钻井技术工艺并初步考察了产气效果。结果表明：潘庄地区3#煤层含气量大、构造及水文地质条件简单,煤层产状稳定且厚度较大,原生结构煤体发育,比较适合U型水平井的施工。煤层气U型水平井具有技术工艺复杂、增产效果明显的特点,先进的工具仪器和技术工艺为煤层气U型水平井施工成功提供了技术保障,其最高产气量达到22 000m^3/d,相当于5-6口普通高产垂直井的产气效果,可为煤矿区煤层气抽采利用提供关键技术支撑。 相似文献
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Incised-valley shale systems are renowned as the fruitful exploration domains. However, the stratigraphic heterogeneity is significant, and thus, identifying the porous compartments within the thin-bedded and fractured shale system is one of the unconventional stratigraphic challenges. We present an innovative scheme for the exploration of the porous unconventional resources within the south Indus basin, Pakistan. The continuous wavelet transforms (CWT) exclusively detects the porous shales within the complete fractured system as compared to the full spectrum seismic data interpretation tool. The seismic amplitude, instantaneous frequency, and reflection strength tools show some tuning effects due to lithology and fluids. However, the tuning block of 28 Hz envelope sub-bands in conjunction with instantaneous phase tool accurately mark out the shale-plugged pinch out reservoirs. The synthetic wedge model based on the conventional seismic wavelet resolves the shale bed (incised-valley shale-filled lens) of about 23 m thickness, but shows limited imaging capability due to frequency band limitation for the porous shale locale. The acoustic impedance based on instantaneous spectral porosity modeling using the tuning volume of 28 Hz CWT has spectacularly resolved the thin-beds (gas shows) within the porosity range of 20 to 30%, which may have implications for future exploration of unconventional stratigraphic plays. 相似文献
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地质导向技术在煤层气水平井施工中的应用 总被引：1，自引：0，他引：1
施工煤层气水平井时,运用地质录井资料、气测资料及伽马测量曲线等地质导向技术控制井眼轨迹在目标煤层中的延伸,能够保证煤层钻遇率符合设计要求。分析了地质导向技术在煤层气水平井水平段施工的导向措施,总结了地质录井、气测和伽马测量等方法的导向特点及作用。通过HCMS-2水平井应用实例,提出了综合运用地质导向技术施工煤层气水平井的具体方法和做好地质导向工作的认识。 相似文献
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为满足鄂尔多斯盆地苏里格气田水平井部署、水平井地质导向及跟踪分析的需求,作者运用岩心观察、薄片鉴定、垂向层序和测井相分析等手段,以辫状河沉积模式为指南,汲取有关的露头和现代沉积定量储集层沉积学成果,对苏里格中部水平井开发区盒8下亚段沉积微相和砂体展布进行了精细描述。在相标志、微相特征和沉积层序研究基础上,以研究区密集井区剖面详细对比、砂体储集层厚度统计为依据,并运用水平井水平段录井资料,综合分析估算出研究区盒8下亚段储集砂体规模参数。作者拟定了沉积亚相、微相划分的3项指标(砂/地比、测井曲线、储渗砂体)。精心编制的砂层组沉积微相和砂体展布图,为水平井部署和地质导向提供了有力支撑。 相似文献
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安塞油田坪桥水平井区沉积微相三维建模研究 总被引：4，自引：0，他引：4
以安塞油田坪桥水平井区为例,探讨了应用水平井和露头资料及标点过程(示性点过程)方法进行沉积微相三维建模的思路与方法,同时对研究区三角洲前缘分流河道的定量结构模式进行了深入的研究。研究表明,坪桥水平井区三角洲分流河道单砂体宽度一般为40～100m左右。砂体结构呈两种模式,其一为“迷宫状”,砂体离散地分布于湖相泥岩中,其二为“拼合板状”,多个砂体在侧向上叠置而形成连片分布的砂体,但部分单砂体间可被泥质或钙质薄层侧积层所隔挡。应用水平井资料和露头资料,可有效地提取三维建模所必须的地质统计学参数。研究表明,采用标点过程方法,可建立符合地质实际的沉积微相三维模型。 相似文献
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探讨苏里格气田水平井地质三维导向技术,为水平井规模化开发提供新的思路和技术。以区域地质背景、区块砂体展布规律为基础,由常规二维地层对比求取地层视倾角发展为地层三维空间对比求取真倾角,精细对比地层及储层展布情况,并结合辫状河沉积微相及其发育特征和随钻参数分析评价开展水平井地质导向分析。研究区盒8段辫状河道主要发育河道充填、心滩微相、废弃河道、越岸沉积4种微相;以沉积微相分析技术为基础的地质三维导向能够有效保证水平段钻遇率。在储层三维空间对比闭合基础上,形成了以沉积微相赋存规律、砂体地质规模及特征分析为核心的水平井地质三维导向技术,完善了水平井地质导向方法。 相似文献
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Stratigraphic and structural interpretative studies have been carried out within the paralic sequence of Agbada Formation in the Niger Delta Basin. The method of study involved integrating sequence stratigraphic techniques with well logs, biostratigraphy, and 3D regional seismic data obtained from several producing fields in the Coastal Swamp depobelt of the onshore Niger Delta Basin. This was targeted at establishing regional sequence stratigraphic and structural framework from well log correlation and seismic mapping so as to better define hydrocarbon leads. Well log correlation using stratigraphic bounding surfaces such as maximum flooding surfaces (MFSs) and sequence boundaries (SBs) indicates that the stratigraphic package was deposited within the Middle to Late Miocene (8.5 to 12.1 Ma) age. Recognized depositional sequences revealed differential thickening and thinning of the associated system tracts (lowstand system tract (LST), transgressive system tract (TST), and highstand system tract) (HST)). This observed stratal behavior has been attributed to the influence of syndepositional tectonic structures that characterize the Coastal Swamp depobelt, which lies within the extensional zone. Flattening of MFSs at various ages indicates observable basinward shift of the depositional center. The genetic units of LST and HST serve as good hydrocarbon reservoir whereas HST and TST constitutes mainly the source and seal packages rocks in the area. Structural interpretation revealed the occurrence of simple/faulted rollover anticline, collapsed crest, regional hanging wall and footwall, horst block, and subdetachment fault structural styles that constitute the key hydrocarbon entrapment mechanisms. Structural top maps show fault-dependent closures which dominate the extensional zone, which could form possible hydrocarbon leads and prospects that should be targeted during exploration studies for development. 相似文献
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针对碎软煤层地面煤层气难以抽采,水平井钻进容易塌孔的问题,在借鉴页岩气和致密气开发先进技术的基础上,研究碎软低渗煤层顶板分段压裂水平井技术。通过优化煤层顶板水平井钻进、定向射孔和分段压裂等工艺流程,从地面抽采碎软煤层中的瓦斯气体。运用该技术在安徽淮北芦岭井田开展了LG01水平井组试验。试验结果表明:LG01水平试验井组日产气量超过1.0×104 m3,与同一井田的压裂直井相比,相当于4口以上直井的产量,实现了碎软煤层从地面高效抽采煤层气的目的。 相似文献
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直井开发煤层气钻井和压裂成本高,控制面积小,单井产气量低;煤层内水平井钻进难度大,风险高,薄煤层中井眼轨迹控制难度大,钻井液有害固相对储层伤害严重,采收率低。基于此,分析贵州织金区块煤系地质构造,提出在煤系地层内稳定的非储层内布水平井,通过压裂造缝沟通水平井上下煤层同时开发多层煤层的新思路。与常规开发方式相比,非储层内水平井具有钻井风险小、储层伤害小、单井产量高的优点,同时还可以开发煤系致密气和页岩气,提高非常规天然气利用率。研究非储层内水平井开发贵州织金煤层气技术,为解决贵州煤系地层煤层多而薄、层间距小等特性煤层气开发难题以及综合利用煤系气提供新的方式。 相似文献
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涪陵页岩气田是我国第一个投入商业化开发的国家级页岩气示范区,与北美相比,涪陵地区地表条件、地质条件和页岩气储层特征更加复杂、储层埋藏更深,开发初期钻井机械钻速低、钻井周期长、成本高。为此开展了涪陵页岩气田水平井组优快钻井技术研究,形成了集水平井组钻井工程优化设计、水平井优快钻井技术、国产低成本油基钻井液、满足大型压裂要求的长水平段水平井固井技术、山地特点“井工厂”钻井技术以及绿色环保钻井技术为核心的页岩气水平井组优快钻井技术体系。在涪陵页岩气田推广应用了290口井,完井256口,平均单井机械钻速提高了182%,平均单井钻井周期缩短了55%,平均单井钻井成本降低了34%。为涪陵页岩气田年50亿m3一期产能建设的顺利完成提供了强有力的技术支撑,对我国页岩气规模开发提供了重要的借鉴和引领作用。 相似文献
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通过对威远地区14口评价井或导眼井五峰组—龙马溪组地层开展系统的笔石生物地层、岩相地层、测井响应、地球化学、元素地球化学等特征分析,证实了威远地区五峰组—龙马溪组古隆起的发育,指出古隆起发育控制页岩的厚度及岩相展布,明确优质页岩展布受古隆起发育控制,并提出水平井井位优化部署建议。主要结论如下:1）从生物地层、岩性地层、电性特征、地层厚度等方面证实在Z4-Z1—WY1—W5—WX井一带存在（水下）古隆起;2）不同时期地层分布及岩相主要受古隆起发育控制,隆起区及周边地层厚度薄,黏土矿物或碳酸盐矿物含量高,坳陷区沉积厚度大,硅质矿物含量高;3）威远地区五峰组页岩沉积期物源多来自其西部或北部,鲁丹阶早期以生物成因石英为主,物源较少,鲁丹阶晚期物源可能来自川南的黔中古陆,不同的物源方向意味着沉积体系的变化;4）鲁丹阶早期（LM1~LM3）地层储层品质最优,产量高,其储层参数平面展布受隆起发育控制,拗陷区域储层品质最好。建议以鲁丹阶早期地层为目标靶体实施水平井,优先部署该层段厚度较大区域水平井,尽量避开隆起发育区。 相似文献
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通过录井、测井、地震、野外剖面与岩心资料的深入剖析, 探讨中上扬子地区下志留统页岩段的沉积相与总有机碳的关系, 预测页岩气有利勘探区。中上扬子地区下志留统龙马溪组为一套20～268 m厚的黑色页岩夹灰绿色泥质粉砂岩沉积, 在等时框架内自下而上可识别出2个三级层序即SQ1与SQ2, 它们分布稳定、可对比性好。下部层序(SQ1) 的海侵体系域(TST)发育一套有利于页岩气形成的富有机质页岩, 此时期呈现出“北面向次深海敞开、东西南三面受古陆围限、陆棚广布”的沉积格局, 深水陆棚相广泛发育, 面积为255000 km2, 平均厚度35 m。受海平面下降的影响, 从下部层序至上部层序水体变浅, 岩相从深水陆棚相黑色页岩向中-浅水陆棚相沙纹层理粉砂质页岩转变。岩相的发育受海平面升降、古陆、海底地形、物源供给等因素的影响, 岩相类型有碳质或硅质或钙质页岩、纹层状页岩、生物扰动粉砂质页岩、沙纹层理的粉砂质页岩、块状砂岩或介壳灰岩薄夹层5类。研究表明, 沉积相对富有机质页岩的形成具有内在的控制作用, 高TOC含量页岩发育于深水陆棚相、中陆棚相和潟湖相中。目前, 已有多口井在龙马溪组页岩获得工业气流, 揭示了该区良好的页岩气勘探前景;综合分析认为涪陵-赤水-仁怀、威远-长宁、鄂西-渝东为中上扬子地区下志留统页岩气勘探的主要方向和有利目标区。 相似文献