Temporal-Spatial Variances of Holocene Precipitation at the Marginal Area of the East Asian Monsoon Influences from Pollen Evidence

The woodland-steppe ecotone in the. southern Nei Mongol Plateau is located at the northern edge of the east Asian monsoon influences. A marked southeastern - northwestern (SE - NW) precipitation gradient exists in this region. Quantitative reconstruction of palaeo-precipitation of this region is helpful to reveal the development of monsoon climate and to predict die future desertification. Based on modern vegetation and surface pollen studies, a pollen-precipitation transfer function in the study region was established. Pollen data from three sediment sequences within the ecotone were used to reconstruct palaeo-precipitation during the Holocene. The processes of precipitation changes in the three sequences were quite different. There was a tendency of precipitation declined from the onset of the Holocene to 1 100 a BP in Haoluku. But, in Liuzhouwan and Xiaoniuchang, both located south of Haoluku, the annual precipitation reached highest values during 7 800 - 6 200 a BP and 7 200 - 5 000 a BP, respectively. The influences of southwestern (SW) monsoon and the variances of topographical conditions have possibly caused these temporal-spatial variances.

Soil quality and sustainable land use in urban-rural marginal area: a case study of Kaifeng

By using the basic theories of physical geography, land resources and ecology, this article analyzes the soil quality of the rural-urban marginal area in Kaifeng. Computer techniques, based on soil samples analysis, are used to study soil quality changes in the Kaifeng’s rural-urban marginal area. While focusing on nutrient circle key links of input and output in soil, relying on numerous practical survey data, this article reveals clearly the impact of land use change on soil quality.

Early-Middle Paleozoic Andes-type Continental Margin in the Chifeng Area, Inner Mongolia: Framework, Geochronology and Geochemistry and Implications for Tectonic Evolution of the Central Asian Orogenic Belt

Three tectonic units have been recognized in the Chifeng area, Inner Mongolia, from north to south, including the Qiganmiao accretionary prism, Jiefangyingzi arc belt and Sidaozhangpeng molasse basin, which formed an Andeantype active continent margin during the early to middle Paleozoic. The Qiganmiao accretionary prism is characterized by a mélange that consists of gabbro, two-mica quartz schist and basic volcanic rock blocks and heterogeneously deformed marble matrix. Two zircon U-Pb ages of 446.0±6.3 Ma and 1104±27 Ma have been acquired and been interpreted as the metamorphic and forming ages for the gabbro and two-mica quartz schist, respectively. The prism formed during the early to middle Paleozoic southward subduction of the Paleo Asian Ocean(PAO) and represents a suture between the North China craton(NCC) and Central Asian Orogenic Belt(CAOB). The Jiefangyingzi arc belt consists of pluton complex and volcanic rocks of the Xibiehe and Badangshan Formations, and Geochronology analysis indicates that the development of it can be divided into two stages. The first stage is represented by the Xibiehe Formation volcanic rocks, which belong to the subalkaline series, enriched LREE and LILE and depleted HFSE, with negative Eu anomalies, and plot in the volcanic arc field in discrimination diagrams. These characters indicate that the Xibiehe Formation results from to the continental arc magmatic activity related to the subduction of the PAO during 400–420 Ma. Magmatism of the second stage in 380–390 Ma consists of the Badangshan Formation volcanic rocks. Geochemistry analysis reveals that rhyolite, basaltic andesite and basalt of the Badangshan Formation were developed in continental margin arc setting. Moreover, the basaltic andesite and basalt display positive Sr anomalies, and the basalt have very low Nb/La values, suggesting that fluid is involved in magma evolution and the basalts were contaminated by continental crust. The sequence of Sidaozhangpeng molasse basin is characterized by proximity, coarseness and large thickness, similar to the proximity molasses basin. According to our field investigation, geochronological and geochemical data, combined with previous research in this area, a tectonic evolutionary model for Andes-type active continental margin of the CAOB has been proposed, including a development of the subduction-free PAO before 446 Ma, a subduction of the PAO and arc-related magmatism during 446–380 Ma, and formation of a molasse basin during 380–360 Ma.

Petroleum geology controlled by extensive detachment thinning of continental margin crust: A case study of Baiyun sag in the deep-water area of northern South China Sea

The relationships between crustal stretching and thinning,basin structure and petroleum geology in Baiyun deep-water area were analyzed using large area 3D seismic,gravity,magnetic,ocean bottom seismic(OBS),deep-water exploration wells and integrated ocean drilling program(IODP).During the early syn-rifting period,deep-water area was a half-graben controlled by high angle faults influenced by the brittle extension of upper crust.In the mid syn-rifting period,this area was a broad-deep fault depression controlled by detachment faults undergone brittle-ductile deformation and differentiated extension in the crust.In the late syn-rifting period,this area experienced fault-sag transition due to saucer-shaped rheology change dominated by crustal ductile deformation.A broad-deep fault depression controlled by the large detachment faults penetrating through the crust is an important feature of deep-water basin.The study suggests that the broad-deep Baiyun sag provides great accommodation space for the development of massive deltaic-lacustrine deposition system and hydrocarbon source rocks.The differentiated lithospheric thinning also resulted in the different thermal subsidence during post-rifting period,and then controlled the development of continental shelf break and deep-water reservoir sedimentary environment.The high heat flow background caused by the strong thinning of lithosphere and the rise of mantle source resulted in particularities in the reservoir diagenesis,hydrocarbon generation process and accumulation of deep-water area in northern South China Sea.

江西九岭南缘古阳寨地区铍矿化伟晶岩独居石U-Pb定年及其地质意义

以江西九岭南缘古阳寨地区铍矿化伟晶岩为研究对象,选取规模较大的藏龙洞铍矿化伟晶岩脉,通过野外地质调查和LA-ICP-MS测定独居石U-Pb年龄测定,初步了解了九岭南缘古阳寨地区花岗伟晶岩地质特征。结果表明,九岭南缘古阳寨地区铍矿化伟晶岩成岩成矿年龄为(138.57±0.78) Ma,归属于早白垩世。铍矿化伟晶岩侵入于九岭南缘古阳寨中细粒含斑二云母二长花岗岩体内部,形成时代略晚于燕山期古阳寨岩体,显示两者在空间和时间上具有密切的成因联系,推测古阳寨地区铍矿化伟晶岩为古阳寨岩体二云母二长花岗岩结晶分异而成。建议针对古阳寨二云母二长花岗岩体内部和外接触带0~5 km范围内,加强调查力度,以期实现该区域内伟晶岩型铍矿找矿突破。

中国东西部陆相页岩油地质特征差异性分析及其对富集规律影响——以胜利探区为例

以胜利探区为例,系统对比研究了中国东西部陆相湖盆页岩油地质特征差异性及其对富集规律的影响。济阳坳陷沙四段上亚段—沙三段下亚段在古地貌、古气候、古水体介质等因素共同控制下,富有机质纹层状碳酸盐页岩大规模分布,富有机质黏土纹层成烃与富碳酸盐纹层成储协同演化为游离烃规模富集提供了有利条件。准噶尔盆地西北缘哈山地区风城组强裂陷作用导致强烈火山活动,在火山喷发物质与古气候共同影响下,富有机质纹层状含碱长英页岩相大规模分布,且成烃成储演化过程中形成较多的长英质矿物,并伴生大量的基质溶蚀孔和晶间孔,为页岩油富集奠定了重要基础。哈山地区在多期逆冲推覆过程中,准原地系统持续生烃、油多气少和相对较好的保存条件以及构造覆压、生烃增压作用产生的异常高压为页岩油高产提供了必要条件。准噶尔盆地东南缘(准东南)芦草沟组在海迹湖咸水环境下,受火山凝灰质与微生物作用影响,形成了富有机质纹层状页岩相夹贫有机质层状白云岩相的主要岩相组合类型。博格达山周缘山前构造带芦草沟组富有机质页岩均进入成熟演化阶段,胜利探区构造相对稳定区具备页岩油勘探前景。

塔里木盆地塔东地区油气地质条件与有利地质体资源潜力

大庆油田塔东探区主体位于塔里木盆地台盆过渡区满西台缘带,勘探程度低,资源潜力大。勘探主要集中在古城地区,未获规模突破。近年来通过老井复查、构造-岩相古地理研究,明确了台缘带油气基础地质条件,落实了成藏有利区带,拓展了塔里木盆地寒武系勘探新类型。结果表明:塔东探区发育玉满裂陷、玉都裂陷槽盆相,斜坡陆棚相等多套烃源岩;寒武系—中下奥陶统台缘带高能礁滩继承发育,多组走滑断裂控储、控藏、控富集;“黑被子”泥岩、“白被子”膏岩2套区域盖层分布广泛,源、储、盖紧密配置,具备规模成藏条件;纵向上,油气受走滑断裂及区域盖层控制,主要分布在中下奥陶统碳酸盐岩地层;横向上,以玉满、玉都裂陷槽为中心,油气规模富集;玉满奥陶系鹰山组上段断溶体、鹰山组下段礁滩-断溶复合体成藏条件优越,发育凝析气藏,是塔东最现实的效益勘探领域;寒武系盐下礁滩体、断控丘滩带源、储、盖配置好,资源潜力大,可作为增储上产的接替领域。塔东探区多领域均展现出万亿立方米的气资源规模,有望快速建成大庆油田稳油增气的重要基地。

吉林省石头口门地区早二叠世砂岩碎屑锆石U-Pb年龄及其地质意义

通过对吉林省石头口门地区早二叠世砂岩进行野外地质考察、薄片镜下观察和碎屑锆石U-Pb年代学研究,探讨其形成时代、物源及构造环境。长石岩屑杂砂岩的碎屑颗粒具有分选和磨圆度差以及成分复杂的特征,表明为近源快速堆积的产物。获得114颗碎屑锆石U-Pb年龄介于480~276 Ma,可划分出晚石炭世—早二叠世(322~276 Ma)和早石炭世(349~323 Ma) 2个主要年龄组,另有4个早古生代和中泥盆世年龄。通过区域岩浆事件对比,推测石头口门地区早二叠世砂岩的物源主要来自华北板块北缘晚石炭世—早二叠世活动陆缘型岩浆岩,少量来自研究区附近的早石炭世岩浆岩、早古生代岩浆弧、晚志留世—中泥盆世弧-陆碰撞岩浆岩以及华北板块前寒武纪变质基底。综合碎屑锆石年龄频谱、沉积以及构造背景资料分析,认为石头口门早二叠世砂岩应是活动大陆边缘环境下海底扇沉积序列的组成部分,并在古亚洲洋闭合过程中作为基质与一系列成分、规模和时代复杂的构造岩块或岩片共同构成了蛇绿混杂岩。

鄂尔多斯盆地府谷地区深部煤层气富集成藏规律及有利区评价

鄂尔多斯盆地东缘神府区块是典型深部煤层气田,资源丰富且勘探开发潜力巨大。2023年10月,神府深部煤层大气田成功申报探明地质储量超1100亿m^(3)。府谷地区位于神府区块中部,是最早深部煤层气生产试验区,但目前对其煤层气的富集成藏规律和勘探开发潜力的认识尚不清楚。综合应用地震、测井、钻井和煤岩测试等资料以查明该地区深部煤层气地质特征、富集成藏规律和有利区分布。结果表明:主力煤层4+5、8+9号煤发育稳定且厚度较大(4+5号煤:3.2~5.8 m;8+9号煤:8.7~13.5 m),有利层段主要分布在煤层中上部位置;宏观煤岩类型主要为光亮-半亮煤,煤体结构主要为原生-碎裂结构煤;受深成变质作用的影响,煤类以气煤、肥煤和焦煤为主,煤的变质程度处于热解生气的高峰期,煤储层表现出中-高含气量(4+5号煤:3.0~12.0 m^(3)/t;8+9号煤:7.5~18.5 m^(3)/t)和中-高含气饱和度(35.0%~115.0%)等特征;主力煤层属于低渗储层((0.01~0.09)×10^(-3)μm^(2)),孔隙结构主要以微孔和小孔为主。提出府谷地区煤层气为“挠褶-断层-水动力”富集成藏模式,煤层气富集区位于构造平缓区和斜坡带。建立深部煤层气地质-工程双甜点评价体系,识别出I类地质-工程甜点区位于东部和西南部,是研究区深部煤层气勘探开发首选区带。因此,该研究认识进一步丰富了深部煤层气富集成藏理论,对鄂东缘深部煤层气勘探开发实践具有重要指导意义。

南海北部陆缘盆地深水区油气勘探新认识及攻关方向

南海北部陆缘盆地深水区已成为我国海洋油气勘探增储上产的重要领域,但由于构造演化史复杂,该区不同凹陷的沉积—构造特征、烃源岩生烃—储层成岩演化和成藏模式均存在明显差异。为准确认识该区油气勘探潜力和方向,基于前人研究成果和勘探实践,在综合分析烃源岩、储层、差异成藏等地质条件的基础上,剖析了南海北部陆缘盆地深水区成藏特征、油气勘探作业面临的挑战,并指出了下一步油气攻关研究方向。研究结果表明:①受地壳拆离作用及强烈薄化影响,该区地层沉积特征特殊,岩石地球物理性质多样;②软流圈差异抬升形成深水区独特的高热流背景,促使区域性湖相、煤型及叠合型等3类烃源灶快速、高强度生烃,生烃门限变浅;③深水盆地群的演化和成盆规模差异大,构造演化控制了盆地几何形态和储集体时空展布,深水区独特的板块构造位置、复杂的构造演化史、温压变化剧烈的地质特征等控制了油气成藏模式。结论认为:①该区油气勘探面临地震资料解析度低、规模有效储层预测困难、勘探成本高等技术与经济的双重挑战;②需要创新形成高地温背景下优质储层差异化分布规律的研究思路;③亟需提升勘探设备能力建设,攻关高效地震采集、“重磁电震”地球物理一体化采集处理、双井架钻探作业、多井段“一趟钻”等勘探关键技术,为我国海洋深水油气勘探开发的高质量发展做好理论和技术支撑。

采煤沉陷区地裂缝对土壤含水率的影响

为了探究地裂缝对深层土壤含水率的影响,以陕北某煤炭基地煤矿区为研究对象,利用统计分析方法分析动态地裂缝和边缘地裂缝对浅层(0.1~0.3 m)和深层(0.5~6.0 m)土壤含水率的影响,并基于克里金插值法解析土壤含水率的时空变化规律.研究结果表明:①竖直方向上,深度为0~2.0 m时,动态地裂缝区和边缘地裂缝区的土壤含水率均低于未扰动区的值;深度为2.0~6.0m时,各区土壤含水率差异不明显,表明地裂缝对土壤含水率的影响深度约为0~2.0 m,即地裂缝对浅层土壤含水率的影响较大,对更深层土壤含水率的影响相对较小.②水平方向上,动态地裂缝区土壤含水率整体低于闭合区,而1年边缘裂缝区土壤含水率整体高于2年边缘裂缝区,表明地裂缝会对土壤含水率的空间分布产生较大影响.综合来看,地表塌陷与地裂缝的出现改变了土壤的结构状态,加速了土壤水分的蒸发,降低了土壤持水性.

上扬子南缘五峰组——龙马溪组页岩地球化学特征及其对风化、物源与构造背景的指示

为深入探讨上扬子地区南缘晚奥陶世—早志留世黑色页岩的物质来源、风化作用和源区构造背景,本文选取典型野外剖面,对五峰组—龙马溪组页岩主量、微量和稀土元素地球化学特征进行系统研究并探讨其地质意义。结果显示:上扬子南缘五峰组—龙马溪组黑色富有机质页岩具有与上地壳相似的贫高场强元素、富集大离子亲石元素特征,∑REE值(103.66×10^(-6)~295.98×10^(-6),平均180.57×10^(-6))整体较高,稀土元素标准化配分模式与上地壳极为相似,呈现“V”型向右倾斜、轻稀土元素富集、重稀土元素平坦、轻重稀土分异明显、Eu负异常明显的特征;特征微量、稀土元素含量及比值,如:La、Ce、La/Yb、Sc/Cr,均表现出与被动大陆边缘特征值相接近;样品成分变异指数ICV值(0.55~14.1,平均2.28)和Zr/Sc—Th/Sc图解指示物源为构造带首次快速沉积产物,不具备沉积再循环特征;较低的CIA值(54.89~71.61,平均65.27)、A—CN—K图解和K_(2)O/Al_(2)O_(3)—Ga/Rb图解表明物源受化学风化作用较小,沉积环境为寒冷、干燥环境;K_(2)O、Rb、Al_(2)O_(3)/TiO_(2)含量较高及Eu负异常指示其源岩以长英质火成岩及花岗岩类的偏酸性地质体为主;综合物源、构造背景判别图解,推断上扬子南缘五峰组—龙马溪组页岩主体形成于被动大陆边缘,物源主要来自于西侧康滇古陆新元古代早期地台盖层,黔中隆起次之,伴随扬子板块东南部中酸性火山物质涌入沉积。

基于二维超声的病灶边缘区影像组学特征对三阴性乳腺癌术后复发的鉴别诊断

目的探讨术前边缘区影像组学分析在三阴性乳腺癌(TNBC)术后复发的鉴别诊断价值。方法回顾性收集2016年1月至2022年6月在海安市人民医院进行TNBC手术切除的139例患者资料,并依据随访结果分为复发组和未复发组。所有患者均接受乳腺二维超声(2DUS)检查。使用Image J基于高频灰阶声像图勾勒病灶边缘区,并提取感兴趣区(ROI)。基于Pyradiomics提取影像组学特征,并运用组内相关系数(ICC)、单因素分析及最小绝对值收缩和选择算子(LASSO)和自相关矩阵进行特征降维。采用Pearson相关分析影像组学特征与Ki-67指数及复发时间的关系。采用多元logistic回归构建影像组学模型,采用ROC曲线、校准曲线及决策曲线评价影像组学模型预测效能。结果排除11例失访者,最终纳入128例患者。按照7∶3比例分为训练集90例和测试集38例。训练集边缘区影像组学特征降维后最终得到5个关键特征(X1:original_glszm_GrayLevelNonUniformity,X2:original_glcm_Contrast,X3:wavelet-HLL_gldm_LowGrayLevelEmphasis,X4:wavelet-HHH_glszm_GrayLevelNonUniformity,X5:wavelet-HHH_glrlm_GrayLevelNonUniformityNormalized)。相关性分析证实X1、X2、X4与Ki-67指数均呈正相关,与复发时间均呈负相关(均P<0.05);X3和X5与Ki-67指数均呈负相关,与复发时间均呈正相关(均P<0.05)。多元logistic回归模型显示X2(OR=1.126,95%CI:1.086~1.165)、X3(OR=1.100,95%CI:1.056~1.143)和X5(OR=1.142,95%CI:1.109~1.172)是TNBC是否复发的独立影响因素。影像组学模型在训练集AUC为0.892(95%CI:0.828~0.962),验证集AUC为0.873(95%CI:0.809~0.943)。校准曲线及决策曲线显示影像组学模型具有良好的校准度和临床实用性。结论病灶边缘区影像组学特征分析具有良好的鉴别诊断效能,可有效预测TNBC术后复发风险。

川东地区新钻区块礁滩沉积模式及有利相带——以板东南缘上二叠统长兴组为例

近年来,四川盆地东部武胜-石柱台内洼地两侧上二叠统长兴组礁滩气藏勘探开发不断突破,卧龙河南缘地区3口生物礁钻井已获天然气近5×10^(8)m^(3),与其相邻的板东南缘长兴组也发现大面积相同的礁滩地震异常体,但其“亚平行层状反射”特征与典型的生物礁地震响应特征具有明显差异,由于该区块钻井少(仅板东18井1口井),研究程度较低,对于该异常体是礁还是滩的地质认识仍然模糊不清。因此,亟待建立本区的沉积模式,为下一步的勘探部署提供理论依据。在对比分析卧龙河南缘及广安高带地区的薄片、测井曲线及地震资料的基础上,结合正演及古地貌分析,开展了本区沉积储层模式及有利相带预测的研究。结果表明:①板东南缘地区长二段岩性以生屑灰岩为主,长三段见生物礁灰岩,认为板东南缘地区具有生物礁和生屑滩纵向叠置发育的条件;②板东南缘台洼边缘前端长顶上隆、振幅减弱、内部断续及空白反射为生物礁的响应特征,台洼边缘后端长顶上隆、振幅减弱、内部亚平行层状反射为礁滩叠置体的响应特征;③恢复了长兴组古地貌,预测了礁滩体有利相带共8.8km^(2);④通过与邻区的井震对比及正演分析,建立了本区台洼边缘前端生物礁、台洼边缘后端礁滩叠置体的沉积模式。板东南缘地区长兴组礁滩沉积模式的建立对台洼礁滩气藏的勘探开发具有重要的指导意义。

鄂尔多斯盆地东缘康宁地区煤系致密气成藏条件与成藏特征

鄂尔多斯盆地作为上古生界的主要储层,为气藏的形成提供充足的气源。研究区气藏主要有上倾尖灭岩性气藏、岩性气藏及岩性-构造气藏。为深入了解上鄂尔多斯盆地东缘康宁地区的气藏特征,从鄂尔多斯盆地内选取一个区域作为研究区,描述气藏特征,明确气藏的分布规律,为天然气的开发利用提供支撑。

不同靶区边缘参数对乳腺癌根治术后容积弧形调强放射治疗计划质量的影响

目的探讨不同靶区边缘参数对乳腺癌根治术后容积弧形调强放射治疗(VMAT)计划质量的影响。方法回顾性分析2021年1月至2022年12月于医院行VMAT的14例乳腺癌根治术后患者的临床资料。所有患者均采用Monaco计划系统设计Tight组、Narrow组、Normal组3组不同靶区边缘参数的VMAT计划,并比较3组靶区剂量学指标[PTV的平均剂量(D_(mean))、最大剂量(D_(max)),2%PTV体积受照射剂量(D_(2%))、98%PTV体积受照射剂量(D_(98%))、50%PTV体积受照射剂量(D_(50%)),适形度指数(CI)、均匀性指数(HI)、剂量梯度指标(GI)]、危及器官(OARs)剂量学指标[患侧肺体积百分比(V_(5)、V_(20)、V_(30))和平均剂量(D_(mean)),健侧肺体积百分比(V_(5))和平均剂量(D_(mean)),心脏体积百分比(V_(5))和平均剂量(D_(mean)),脊髓最大剂量(D_(max))及健侧乳腺平均剂量(D_(mean))]及计划参数[计划控制点数(CP)、机器跳数(MU)和出束时间(T)]。结果Tight组的D_(mean)、D_(max)、D_(2%)、D_(50%)、HI、GI均低于Narrow组和Normal组,且Narrow组的D_(mean)、D_(2%)、D_(50%)、HI、GI均低于Normal组,差异有统计学意义(P<0.05);Narrow组和Normal组的D_(max)比较,差异无统计学意义(P>0.05);Tight组的D_(98%)和CI均高于Narrow组和Normal组,且Narrow组的D_(98%)高于Normal组,差异有统计学意义(P<0.05);Narrow组和Normal组的CI比较,差异无统计学意义(P>0.05)。Tight组的心脏V_(5)、D_(mean)和脊髓D_(max)均低于Narrow组和Normal组,且Narrow组低于Normal组,差异有统计学意义(P<0.05);Tight组和Narrow组的健侧乳腺D_(mean)均低于Narrow组,差异有统计学意义(P<0.05);3组其他OARs剂量学指标比较,差异均无统计学意义(P>0.05)。Tight组的CP、MU和T均高于Narrow组和Normal组,且Narrow组高于Normal组,差异有统计学意义(P<0.05);Tight组的MU高于Narrow组和Normal组,差异均有统计学意义(P<0.05);Narrow组和Normal组的MU比较,差异无统计学意义(P>0.05)。结论设计乳腺癌根治术后VMAT计划时,合理设置靶区边缘参数可改善剂量学特性,有助于提高放射治疗的精准性和治疗效果。

基于暂态稳定裕度灵敏度的多直流送出能力提升控制方法

多直流送端系统内某一直流线路发生闭锁故障后,可以通过对其他非故障直流进行紧急功率支援(emergency DC power support,EDCPS)控制来提升系统受扰后的稳定性。如何有效量化EDCPS对系统稳定性的改善效果,从而提高安稳控制的效率,目前缺少相应的指标;现有研究也尚未解决如何利用EDCPS最大程度提升多直流综合送出能力的问题。应用扩展等面积法(extended equal area criterion,EEAC)定量分析了EDCPS提升多直流送端系统暂态稳定性的机理;以两送出直流系统为例,推导了基于EEAC的暂态稳定裕度η对EDCPS的灵敏度公式;在此基础上,提出一种在不增加相关设备投入的前提下利用系统中现有稳控措施并结合暂态稳定裕度灵敏度的多直流送出能力提升控制方法,通过计算备选直流的暂态稳定裕度灵敏度,可以完整反映系统在遭受大扰动后的动态特性以及定量评估EDCPS对系统受扰后稳定性的改善效果,避免过去仅凭运行人员经验选取支援直流的问题,提高计算效率;最后,选取西北电网实际算例对所提出的多直流送出能力提升控制方法有效性进行仿真验证,以期为从事交直流混联电力系统稳定性分析与控制的学者和工程师们提供有益的参考。

Characteristics and genesis of clay minerals in the northern margin of the Qaidam Basin

In order to develop appropriate reservoir protection measures in the northern margin of the Qaidam Basin and improve its oil and gas recovery efficiency,characteristics of clay minerals from eleven clay rock samples from the northern margin of the Qaidam Basin were investigated using X-ray diffraction analysis,the Scanning Electron Microscope（SEM）and energy spectrum analysis.Clay mineral composition and distribution characteristics of the main hydrocarbon reservoirs,i.e.,from the Jurassic and Paleogene-Neogene,were explored.We analyzed the main factors which affected these attributes.The results show that the major clay minerals in the northern margin are chlorite,kaolinite,illite,smectite and illite/smectite inter-stratified minerals.Illite is the most widely spread clay mineral in this area. Chlorite is mainly found in the entire Neogene and in shallow horizons of the Paleogene.Smectite is enriched in the shallow Paleogene-Neogene.There are large amounts of kaolinite and illite/smectite inter-stratified minerals in the Jurassic.The major factors affecting the different development of clay minerals in the region are properties of parent rocks,paleoclimate and paleowater media conditions, diagenesis transformation,tectonic and terrain conditions.

Analysis of the Criticizes for Zootechnics Development in a Mountain Area of Italy

The paper considers the main causes of the difficulties of zootechnics in Friulian mountains （Italy）, evaluating different approaches. From the methodological point of view, there were analyzed the different aspects that causes the present crisis in this territorial contest and that, contextually, at the same time, prevent its recovery. The procedural pathway followed these steps： analysis, synthesis, comparison, deduction and induction. The results showed that there are technical, social, environmental, political and infra-structural aspects that cause this stated economical emergency for the compartment. A ＂new rural paradigm＂, in particular, the multi-functionality of the farm seems to be the road to the progress of mountain regions. Unfortunately, there are no definitive universal answers, hut individual solutions that should be investigated and calibrated for specific local resources.

准噶尔盆地西北缘哈山地区二叠系风城组页岩油储层特征及其控制因素

准噶尔盆地西北缘二叠系风城组蕴含丰富的页岩油资源,且在玛湖凹陷和乌夏地区的油气勘探取得重大突破,邻近的哈山地区也具有一定的勘探潜力。通过岩石薄片观察、扫描电镜分析、有机地球化学测试、XRD分析和储层物性分析等,对哈山地区风城组页岩油储层特征及其控制因素进行了研究。研究结果表明:(1)哈山地区风城组页岩油储层岩性主要为长英质页岩、钙质页岩和混积页岩,风城组页岩整体属于好—最好烃源岩,有机质类型以Ⅱ1型和Ⅱ2型为主,有机质主要处于未成熟阶段,部分推覆体下盘页岩有机质进入成熟早期阶段。(2)研究区页岩油储层孔隙度平均为2.32%,属于低孔储集层,储集空间以无机孔和微裂缝为主,有机质孔含量较低。(3)研究区风城组页岩油储层的发育主要受沉积相、成岩作用和构造活动的控制,其中沉积相不仅决定了岩石类型,还控制了有机质的富集程度;压实作用和胶结作用对储层物性具有负面影响,溶蚀作用可以大幅改善储集物性;构造活动形成的微裂缝不仅可以为页岩油赋存提供储集空间,还可以为油气运移提供通道,进而改善了页岩油储层的渗透性。