Research on the fault controlling mechanism of geothermal water in Zhangzhou Basin

Fault has an important influence on the storage and movement of geothermal water. The Zhangzhou Basin is wholly located in a granodiorite rock mass. Due to the low permeability of granodiorite, faulted structure has an evident control action on the hydrothermal activity of geothermal fields. Hot springs in Zhangzhou Basin crack along Pingtan-Dongshan Fault to the northeastern direction and emerge along Fu'an-Nanjing Fault. Through measurement of the temperature of several hot springs in the Basin, we found the temperature along the northwestern direction of Zhangzhou-Tianbao Fault is high and the temperature gap between the two sides of Yangxi-Yuanshan Fault is huge; the estimation of geothermal reservoir temperature of geothermal water through quartz geothermometer indicates that the geothermal reservoir temperature of the northern area of Nanjing-Xiamen Fault is obviously higher than that of southern area. Such result indicates that Fault obviously obstructs underground heat source. Under the condition that the average geothermal gradient of the Zhangzhou Basin is set, the circulation depth of the geothermal water of the Zhangzhou Basin measured by geothermal reservoir temperature is 3 550-5 200 m and the circulation depth of the geothermal water of the north of Nanjing-Xiamen Fault is deeper than that of the South.

Vertical migration through faults and hydrocarbon accumulation patterns in deepwater areas of the Qiongdongnan Basin

In the Qiongdongnan Basin, faults are well developed. Based on the drilling results, the traps controlled two or more faults are oil-rich. However, when only one fault cut through the sand body, there is no sign for hydrocarbon accumulation in the sandstone. In terms of this phenomenon, the principle of reservoir-forming controlled by fault terrace is proposed, i.e., when the single fault activates, because of the incompressibility of pore water, the resistance of pore and the direction of buoyancy, it is impossible for hydrocarbon to accumulate in sandstone. But when there are two or more faults, one of the faults acts as the spillway so the hydrocarbon could fill in the pore of sandstone through other faults. In total five gas bearing structures and four failure traps are considered, as examples to demonstrate our findings. According to this theory, it is well-advised that south steep slope zone of Baodao-Changchang Depression, south gentle slope zone of Lingshui Depression, north steep slope zone of Lingshui Depression, and north steep slope zone of Baodao Depression are the most favorable step-fault zones, which are the main exploration direction in next stage.

GEOCHEMISTRY AND TECTONIC ENVIRONMENT AND RESERVOIR FORMATION OF MANTLE-DERIVED NATURAL GAS IN THE SONGLIAO BASIN, NORTHEASTERN CHINA

During several decades of exploration, a number of mantle-derived natural gas pools have been discovered in the vicinities of deep faults in the Songliao Basin, northeastern China. The natural gas in these pools has a δ13C1 value of ?16.50/00 to ?24.20/00, a reversed arrangement in the amount of carbon isotopes in methane and its endogamous products (namely, δ13C1 >δ13C2 >δ13C3 >δ13C4), a 3He/4He value of 1.97 to 2.34×10-6,and an Ar/36Ar value of 1063 to 1949. This indicates a mantle 40 source for the natural gas. The trace elements Cd, In, Te and Re, never found in organic-sourced hydrocarbons, are highly enriched in certain crude oils from the Basin; respectively, concentrations of these elements were found to be 751, 28, 16 and 323 times the average crustal values in China, and this also supports a mantle-derived natural gas origin. The characteristics of mantled-derived magmatic rocks, hydrothermal fluids and gaseous fractions distributed in and near the deep Songliao Basin faults indicate that rifting tectonics is providing the mechanisms for this outgassing of the mantle. Deep extensional (normal) faults provide pathways for upward movement of these materials, and in the Songliao Basin, these deep rift fault zones are associated with reservoir occurrence and cap rock seals, forming good sites for accumulation of mantle-derived natural gas. Furthermore, a layer of low velocity, low density and high conductivity in the deep crust has been identified as a potential reservoir for mantle-derived natural gas.

A Research on the 2014 Wenzhou M4.2 Earthquake in the Shanxi Reservoir

Complete records of more than 3,000 earthquake events in the Shanxi, Wenzhou reservoir earthquake sequence were recorded from August to November,2014 by the high-density,high-resolution monitoring stations of the Zhejiang Regional Digital Seismic Network and the reservoir earthquake monitoring network,with a maximum magnitude of M4. 2. Based on 3-D epicenter location, focal mechanism solutions, and in combination with the geological and tectonic characteristics of the reservoir area,the earthquake sequence is discussed in this paper. The linear fitting of the Hypo SAT location results show that the main shock occurred in the NW trending fault and the earthquake sequence is concentrated in bands along the active faults,with a strike of305 °,dipping SW with dip angle of 85 °. By using P-wave first motion symbols, we obtained the average focal mechanism of M ≥ 3. 5 earthquakes,with a strike 308 ° and dip 84 ° for nodal plane II. The field geological survey and research show that the strike,dip and rake of nodal plane II are roughly consistent with the occurrence of the Shuangxi-Jiaoxi fault. The comprehensive analysis reveals that the NW-trending Shuangxi-Jiaoxi fault is the seismogenic structure of the earthquakes.

Reservoirs properties of slump-type sub-lacustrine fans and their main control factors in first member of Paleogene Shahejie Formation in Binhai area, Bohai Bay Basin, China

High-yielding oil wells were recently found in the first member of Paleogene Shahejie Formation,the Binhai area of Qikou Sag,providing an example of medium-and deep-buried high-quality reservoirs in the central part of a faulted lacustrine basin.By using data of cores,cast thin sections,scanning electron microscope and physical property tests,the sedimentary facies,physical properties and main control factors of the high-quality reservoirs were analyzed.The reservoirs are identified as deposits of slump-type sub-lacustrine fans,which are marked by muddy fragments,slump deformation structure and Bouma sequences in sandstones.They present mostly medium porosity and low permeability,and slightly medium porosity and high permeability.They have primary intergranular pores,intergranular and intragranular dissolution pores in feldspar and detritus grains,and structural microcracks as storage space.The main factors controlling the high quality reservoirs are as follows:(1)Favorable sedimentary microfacies of main and proximal distributary gravity flow channels.The microfacies with coarse sediment were dominated by transportation and deposition of sandy debris flow,and the effect of deposition on reservoir properties decreases with the increase of depth.(2)Medium texture maturity.It is shown by medium-sorted sandstones that were formed by beach bar sediment collapsing and redepositing,and was good for the formation of the primary intergranular pores.(3)High content of intermediate-acid volcanic rock detritus.The reservoir sandstone has high content of detritus of various components,especially intermediate-acid volcanic rock detritus,which is good for the formation of dissolution pores.(4)Organic acid corrosion.It was attributed to hydrocarbon maturity during mesodiagenetic A substage.(5)Early-forming and long lasting overpressure.A large-scale overpressure compartment was caused by under-compaction and hydrocarbon generation pressurization related to thick deep-lacustrine mudstone,and is responsible for the preservation of abundant primary pores.(6)Regional transtensional tectonic action.It resulted in the structural microcracks.

深层-超深层致密储层天然裂缝分布特征及发育规律

天然裂缝是深层-超深层致密储层的有效储集空间和主要渗流通道,影响着致密储层油气的运移、富集、单井产能、开发方式及开发效果。通过对近年来致密储层裂缝研究成果总结和文献综述,分析了深层-超深层致密储层天然裂缝分布特征及发育规律。将致密储层天然裂缝分为大尺度裂缝、中尺度裂缝、小尺度裂缝和微尺度裂缝4个级别。不同尺度裂缝分布具有幂律分布的特点,裂缝尺度越大,数量越少;裂缝尺度越小,数量越多。大、中尺度裂缝主要起渗流作用,小尺度裂缝主要起渗流和储集作用,而微尺度裂缝主要起储集作用。在地层埋藏过程中的应力体制演化决定了不同时期天然裂缝的类型、产状及其力学性质;构造应力大小、岩石力学层的力学性质和厚度差异控制了多尺度裂缝的形成分布及其发育程度。构造变形导致不同构造部位的局部应力和应变分布产生差异,增强了裂缝发育的非均质性。逆冲断层通过控制其上盘地层变形控制了“裂缝域”的分布规律;走滑断层的组合样式、活动方式和岩石力学层共同控制了相关裂缝的三维空间展布。裂缝形成演化过程中的开启-闭合规律决定了裂缝的储集空间,记录了裂缝有效性的演化历史。

青藏高原东缘及邻区强震构造:专辑序言

青藏高原东缘由多个次级构造单元组成了独特的“多层次挤出-旋转活动构造体系”,是调节高原物质向东挤出的构造转换带,发育了高密度的活动断裂,强震频度高且强度大,而且地质地貌复杂,成为我国地震灾害问题最为突出的地区之一。近年来,伴随全国地震灾害风险普查、城市活断层探测、地震科学实验场建设、工程场地的地震安全性评价以及重大工程与城镇区的活断层鉴定与地壳稳定性评价等工作的深入开展,高精度遥感、构造地貌、古地震和第四纪年代学等方法的广泛应用,显著提升了青藏高原东缘及邻区强震构造的调查研究程度。为了及时交流这方面的最新研究成果,支撑区域防震减灾及重要工程和基础设施建设的地质安全评价等工作,《地震科学进展》编辑部组织了“青藏高原东缘及邻区强震构造”成果专辑,征集了活断层与地震、甘肃积石山地震以及相关领域的研究综述等代表性学术论文20余篇,本期《青藏高原东缘及邻区强震构造专辑Ⅰ》优选了10篇论文,后续还将推出《青藏高原东缘及邻区强震构造专辑Ⅱ》,希望这些成果可提升对区域强震活动特征与孕震构造机制的理解,并为区域强震危险性分析和有效防范强震灾害风险提供科学依据。

徐家围子断陷沙河子组主干断裂形成演化与地层剥蚀特征

主干断裂的活动控制着徐家围子断陷沙河子组的建造与改造。为了明确断裂活动,运用位移距离曲线方法系统分析了徐家围子断陷主干断裂的生长活动特征,通过不整合面下的同向轴特征分析了徐家围子断陷沙河子组沉积末期的剥蚀改造作用。结果表明:徐家围子断陷主干断裂分段特征明显,徐西断裂与宋西断裂在火石岭组沉积时期分别是数条分段的小断裂,在沙河子组沉积时期连通为整条断裂并持续控陷活动;徐中断裂在沙河子组沉积时期弱伸展弱控陷,在沙河子组沉积末期作为薄弱带发生压扭反转;徐东断裂带中的徐东正断层在沙河子组沉积时期弱控陷,徐东逆断层在营城组一段沉积末期的反转作用下形成;沙河子组沉积末期的反转作用对沙河子组厚度与构造格局产生明显改变,沿徐西断裂与宋西断裂存在较强的剥蚀,徐西断裂北端升平凸起尤为强烈,徐中断裂压扭反转产生一定的走滑分量并遭受剥蚀,徐东逆断层在营城组一段沉积末期的反转中形成,对沙河子组厚度无明显改变,但对徐东构造带构造格局产生明显影响。研究成果可为徐家围子断陷古构造恢复与进一步勘探提供理论参考。

托普台南区块断溶体油藏栅状断片结构数值模拟

塔河油田托普台南区块断溶体油藏开发初期产量高,后期暴性水淹和快速见水井多,产量递减快,针对此类特征,目前尚未建立较好的模拟方法。结合断溶体油藏岩溶特征、地震特征、实钻井井储关系以及三带结构提出断溶体油藏栅状断片结构,根据此认识,通过融合断层自动提取技术和蚂蚁体属性,得到断裂指示因子,用以刻画栅状断片储集体,利用张量属性刻画溶蚀孔洞型储集体,建立双重介质组分模型,开展数值模拟研究。结果表明:栅状断片结构是断溶体油藏的主要导流通道;断裂指示因子比断层自动提取技术和最大似然更适合表征栅状断片结构,并在通水源处与张量属性匹配度高,在其他区域匹配性差;与单重介质模型相比,基于栅状断片结构的双重介质模型拟合精度更高,更能反映断溶体油藏生产动态特征。

惠民凹陷江家店油田低序级断层精细解释及控藏作用

江家店油田地质构造复杂,内部断层十分发育,预示着其依旧有较大的油气勘探潜力。由于该区发育众多断距较小的低序级断层,且目前对低序级断层的识别和勘探研究程度较低,因此,需要对低序级断层的构造精细解释及其控藏作用进行研究。该区发育北东-南西向、近东西向以及南北向三组低序级断层,在二级、三级断层附近,低序级断层与主干断层以斜交式分布,远离二级、三级断层,低序级断层呈现不同方向分布。利用相干体切片方法能够识别出江家店油田低序级断层,通过对低序级断层的构造精细解释,进而分析该区成藏模式,主要有构造控制的层状油藏和构造-岩性油藏,此外有少量透镜体岩性油藏。低序级断层的精细解释及其控藏作用的研究对油气的勘探开发具有重要意义。

顺北中部超深层断控缝洞型油气藏储集体特征与实践应用

超深层碳酸盐岩储层非均质性强,其内部结构受地震资料精度限制,规模储层预测和分布认识存在难度。选取顺北中部北东向断裂体系的顺北4号断裂带为研究对象,开展断裂构造破碎成储物理模拟实验、井震精细标定、模型正演、储集体表征、储集体地质模型研究,提出断裂面附近发育多个由空腔、裂缝带组成的多组缝洞集合体,建立了走滑断裂栅状储集体结构模式,阐明走滑断裂栅状储集体的成因机制与主控因素,构建了断裂带规模储集体“一体多栅”结构模型,形成了断控储集体空间定位与“一井多控、一井一靶、一井多靶”分类井轨迹设计方案。成果应用指导了顺北4号、顺北8号断裂带钻井轨迹设计,实现了断控缝洞型复杂油气藏的“少井高产”,新增一个百万吨产能新阵地,对我国其他盆地超深层断控型油气藏的勘探具有一定指导与借鉴意义。

碳酸盐岩地层断裂结构特征及油气地质意义——以青州云门山地区下古生界断裂为例

为明确济阳坳陷下古生界碳酸盐岩地层断裂结构对油气成藏的控制作用,文中选取青州云门山地区碳酸盐岩露头断裂进行野外地质考察,利用岩心、野外露头、分析化验等资料,对碳酸盐岩地层断裂结构及其控藏作用进行系统研究,建立了多期方解石胶结、泥质充填和“三元”断裂结构,揭示了3种断裂结构差异化控藏作用。研究认为:多期方解石胶结断裂结构对油气具有垂向输导和横向封堵双重作用,控制油气沿大型油源断层两侧断块圈闭选择性成藏;泥质充填断裂结构对潜山油气成藏具有明显的封堵作用,控制油气在不同的断层-不整合油藏中大规模富集成藏;“三元”断裂结构具有破碎带和裂缝带输导、角砾岩带封堵的双重作用,控制油气主要沿油气来源方向的断层下盘呈梳状富集成藏。断裂结构差异化控藏模式将为济阳坳陷下古生界碳酸盐岩潜山油气勘探提供理论依据。

南苏丹境内裂谷盆地源上构造-岩性油藏成藏主控因素与成藏模式

以钻井、测井及三维地震资料等为基础,通过岩心分析、连井对比、油气运聚模拟、地震反演及多信息叠合等方法,从油源条件、储-盖组合和输导体系3个方面对南苏丹境内Melut和Muglad 2个裂谷盆地源上构造-岩性油藏成藏的主控因素进行了分析,并探讨了成藏模式。研究结果表明:①Melut和Muglad盆地均发育早白垩世第Ⅰ裂陷期优质烃源岩,厚度大、面积广、有机质类型好、成熟度适中,具有良好的油源条件;Melut盆地古近系Yabus组、新近系Jimidi组和Muglad盆地白垩系Aradeiba组发育三角洲相和河流相沉积,河道和水下分流河道微相砂体的含砂率、砂岩厚度均适中,且不同层序内河道的河型存在垂向演化,发育泛滥平原和水下分流间湾微相局部封隔带,形成多套源上砂泥互层储-盖组合,为形成规模构造-岩性圈闭提供了条件;边界控盆断裂与盆缘斜坡区控凹断裂是沟通主力烃源岩与源上目的层的主要油气垂向运移通道,源上层段发育的多期不整合面和富砂地层形成了多个侧向优势运移路径(输导脊),油源断裂与输导脊耦合控制Melut和Muglad盆地源上构造-岩性油藏的有利区带。②Melut盆地Yabus组、Jimidi组以及Muglad盆地Aradeiba组具备形成源上规模构造-岩性油藏的石油地质条件,成藏模式可分为“断裂垂向运移型”、“断裂垂向运移-不整合面侧向输导型”和“断裂垂向运移-连通砂体侧向输导型”3种。

渤海湾盆地廊固凹陷古近系沙河街组油藏单元精细表征

依据岩心相、测井相、岩屑分析化验等资料,利用点-线-面的油藏单元表征方法,对渤海湾盆地廊固凹陷古近系沙河街组的微构造、主力层油藏单元类型及油水连通关系进行了详细研究。研究结果表明:(1)廊固凹陷古近系沙河街组主要发育构造型油藏单元和“断砂配置”型油藏单元。安11井区Es_(4)^(上)-Ⅰ砂组1小层、2小层、3小层和4小层的油藏单元数量分别为6个、5个,3个和2个;安22井区Es3中-Ⅱ砂组3小层和7小层的油藏单元均为5个,其他小层油藏单元数量不等。(2)安11井区Es_(4)^(上)-Ⅰ砂组油藏单元砂体连通程度和流体连通程度均较高;安22井区Es_(3)^(中)油藏单元类型、空间分布特征均较为复杂,油藏单元砂体连通程度较高、流体连通程度相对较低。(3)在实施油藏单元作为开发单元后,安11井区和安22井区各小层的单井日产原油量均有增加。通过油藏单元的精细表征,不仅能发现勘探开发中的滚动评价目标,而且可为开发过程中动态储量及经济可采储量的标定提供准确的油层厚度、油藏边界及油藏分布范围等。

顺北地区碳酸盐岩断控缝洞体油气产能定量化估算技术

走滑断裂带及其控制的缝洞体是顺北地区奥陶系新的勘探领域,探索断控缝洞体储层单井产量多属性量化预测技术,为顺北地区断裂带井位部署与井轨迹优选提供科学依据和技术支撑。断控缝洞体储层中,断裂是油气运移通道,其纵向延伸和宽度是断裂的通源性,主干断裂与次级断裂平面交汇结构表征断裂的汇聚性,通源性和汇聚性表征成藏断裂特征。断控缝洞体中缝洞是储集空间的主体,断控缝洞体储层规模和断裂裂缝分布密度表征缝洞特征。断控缝洞体储层的单井产量既与断裂特征有关,更与缝洞特征有关。因此,量化的断裂特征和缝洞特征是单井产量量化预测的基础。地震数据及其多种属性的断层精细解释,量化后得到断裂特征值。结构张量属性圈定断控缝洞体储层范围,异常体振幅属性表征缝洞的分布及其体量,最大似然概率属性表征断裂裂缝分布密度,3种属性融合得到缝洞特征值。最后将量化的断裂特征值和缝洞特征值融合为断控缝洞体特征值,与实测钻井的年产液量进行统计分析,得到年产液量与断控缝洞体特征值的统计关系式,实现断控缝洞体储层单井产量的量化预测。

基于小波边缘分析与井-震联合建模的波阻抗反演技术在乌尔逊断陷储层预测中的应用

针对乌尔逊断陷构造复杂、储层横向非均质性强、含油砂体小而薄预测难的问题,应用小波边缘分析与井-震联合建模的波阻抗反演技术,从地震记录中直接提取反映构造和岩性变化的地震属性特征参数,与测井声波阻抗数据一起建立初始模型并参与波阻抗模型的扰动修改。此反演技术弥补了井间插值建模过程中井间高频成分的缺失和井间岩性的局部变化细节,避免了常规波阻抗反演过程中由于初始模型不准确而产生的错误信息,提高了地震资料识别“小而薄”砂体的分辨能力。结果表明:受东部物源控制,乌尔逊断陷铜钵庙断裂带发育扇三角洲-半深湖(深湖)沉积体系;受断裂坡折带影响,在铜钵庙断层的下降盘发育一系列扇三角洲前缘砂体。实际钻井结果与钻前预测对比表明,井点处砂体顶界构造深度的相对误差小于0.3%,砂体厚度的相对误差小于3.84%,预测精度满足精细储层预测要求。研究成果可为乌尔逊断陷精细油藏描述和井位部署提供依据。

基于1D-RSLBCNN的齿轮箱故障诊断

针对传统故障模型参数多,训练和检测时间长的问题,提出了基于残差结构和局部二进制卷积(1D-RSLBCNN)的齿轮箱故障诊断方法。其利用局部二进制卷积层来替代传统卷积层,在减少模型参数的同时,加快了训练速度和收敛速度;同时在网络模型中引入残差结构,避免了由于网络深度的增加引起的正确率饱和甚至下降的问题。实验结果表明,局部二进制卷积层的参数量为传统卷积层的1/3,诊断准确率更是高达99.7%。与其他模型相比,具有更稳定、可靠的预测精度。

基于多信息融合的自适应局部线性嵌入算法

局部线性嵌入算法LLE的降维性能与挖掘的流形结构密切相关,但LLE挖掘的流形结构单一,并且对邻域参数选取敏感,无法提取全面的流形局部结构,限制了LLE的降维性能。为此,本文提出基于多信息融合的自适应局部线性嵌入算法MIF-ALLE。MIF-ALLE首先利用切空间近似判据自适应选择邻域参数,获取更准确的局部邻域;然后,将局部邻域中蕴含的切空间角度信息与局部线性信息相融合,挖掘更全面的流形局部结构,降低局部低维嵌入的偏差;最后,在公开轴承数据集以及实验室提取的轴承数据集上进行实验验证。实验结果表明:MIF-ALLE可以挖掘更全面的流形结构,提取更显著的特征,轴承故障诊断准确率最高可达100%。

塔里木盆地顺北5号走滑断裂带分层分段特征及构造演化

塔里木盆地超深层断溶体油气藏主要沿走滑断裂带分布,远离断裂带地区油气勘探效果差,即走滑断裂带的活动规模控制了油气藏的规模。顺北5号走滑断裂带为超大型走滑断裂带,具有埋藏深,内部结构复杂,分层分段性极强的特点。通过高品质三维地震资料,对顺北5号走滑断裂带进行系统的几何学、运动学和动力学研究,提出以下认识:顺北5号走滑断裂带具有极强的分层性,可划分为5个构造层;该断裂带分段活动特征明显,南段和北段具不同的运动学特征,南段经历了5期演化,北段经历了4期演化。