In the context of the evolving global energy landscape, tight gas fields have gained in-creasing significance due to their low-porosity and low-permeability reservoirs, where natural fractures play a critical role in improving permeability and enhancing storage capacity. Foreland basins, such as the Dibei area in the northern Kuqa Depression of the Tarim Basin, are typical hosts for tight gas reservoirs, but the complex fracture development induced by multiple tectonic movements restricts natural gas exploration. This study employs core observation, imaging logging analysis, and thin-section microscopy to characterize the genetic types and development features of natural fractures in the Ahe Formation. Results show that 54% of natural fractures in the Dibei area are structurally originated, predominantly high-angle and open. The highest fracture density (0.351 fractures/m), six times that of other regions, occurs in the upper horst zones. Three fracture patterns are identified, namely fault–fold, fault-related, and monocline types. Fault–fold fractures are most developed due to folding and thrusting, while monocline zones are poorly fractured. Structural fractures are best developed in horst crests with fault–fold patterns. Fracture development is jointly controlled by folds, faults, stress, and lithology, with distinct characteristics across different structural positions and lithological combinations. Clarifying the development characteristics and distribution patterns of natural fractures in the Ahe Formation of the Dibei area facilitates accurate evaluation of high-quality reservoirs, providing crucial geological basis for optimizing hydrocarbon sweet spots and refining accumulation models in the region.

The Jurassic Lianggaoshan Formation in the northeastern Sichuan Basin is a key exploration target for shale oil. However, due to limited exploration in this area, the shale reservoir characteristics remain unclear. Experiments such as X-ray diffraction mineral analysis, scanning electron microscopy analysis, high-pressure mercury intrusion, and low-temperature nitrogen adsorption were conducted to systematically study the storage space types and fractal features of the Lianggaoshan Formation shale reservoir. The primary mineral composition of the Lianggaoshan Formation reservoir in the northeastern Sichuan Basin is clay minerals, with an average content of 51.57%, followed by feldspar and quartz minerals at an average of 47.11%, while carbonate minerals are scarce, averaging 2.69%. The dominant storage space types mainly include interlayer pores of clay minerals, intergranular pores between quartz and feldspar, and micro-fractures. The low-temperature nitrogen adsorption curve of the Lianggaoshan Formation shale aligns with type Ⅳ in the classification system of the International Union of Pure and Applied Chemistry, indicating slit-type pores. Based on the morphology of mercury intrusion curves and reservoir physical properties, the reservoir is divided into four types. From type Ⅰ to type Ⅳ, drainage pressure and median pressure increase, whereas maximum mercury saturation decreases, leading to enhanced reservoir heterogeneity. The "FHH"model calculations show that the pore surface fractal dimension (DN1) is greater than the pore structure fractal dimension (DN2), indicating that the pore surface exhibits greater complexity than the internal pore structure. The average fractal dimension D1 of large pores, calculated using the water saturation method, averages 2.991 2, while that of small pores (D2) averages 2.679 2. The larger pores have a fractal dimension closer to 3 and exhibit a more concentrated distribution, indicating that highly heterogeneous large pores contribute more significantly to the reservoir. Correlation analysis shows that there is a correlation between D and the contents of minerals (quartz and clay minerals) as well as pore-throat struture parameters, proving that large pores are the main contributers to the shale reservoir space in the study area. Through qualitative and quantitative analyses, this paper conducts a reservoir evaluation of the Lianggaoshan Formation shale in the northeastern Sichuan Basin, offering insights for the subsequent evaluation and selection of favorable exploration intervals in this area.

In recent years, new breakthroughs have been made in the exploration and evaluation of the Yanchang 8 formation in the middle part of the western margin of the Ordos Basin, and a number of Wells have been tested to obtain high production, which has become a real development resource of the basin. However, the understanding of the Chang-8 series in the new area of the western margin is still weak, and the sedimentary and reservoir characteristics are not systematically studied. In this paper, the deposition and reservoir characteristics of Chang 8 strata in new area are studied in detail by means of outcrop, drilling core, cast thin section, conventional thin section, X-ray diffraction, scanning electron microscope and mercury injection. The results show that a multi-stage braided river delta plain superimposed sedimentary system is developed in the middle part of the western margin of the Ordos Basin, with large sand bodies in the west and thinning from west to east. The reservoir space is dominated by intergranular pores, and the pore types are mostly combination, mainly developed intergranular pores and feldspar dissolved pores, with an average porosity of 11.28

Deep reservoirs associated with gravity-flows are garnering considerable attention. Predicting reservoirs deposited by nearshore subaqueous fans is challenging and often underreported in seismic sedimentology analysis. Utilizing post-stack seismic attributes is a quick and straightforward method for quantitatively characterizing these reservoirs. However, reservoir prediction deteriorates when dealing with complex sedimentary volumes and intricate tectonic development. Spectral decomposition (SD) offers an alternative approach to optimize the seismic data. The frequency-dependent S-transform (ST) holds great potential in seismic interpretation. SD based on the ST was employed in the seismic sedimentary characterization of steep slope complex fan reservoirs. Three fourth-order sequence stratigraphic boundaries and three complex fans were ideally shown on seismic frequency decomposition profiles. A 20 Hz seismic sedimentology analysis frequency was determined by comparing three spectral decomposition results following the well-seismic reflection analysis. The internal architectures of fan deltas and the individual outlines of nearshore subaqueous fans were more distinguishable in 20-Hz frequency decomposition data than in full-frequency data. The progradation direction of steep slope fans can be better recognized in frequency decomposition profiles compared to full-frequency seismic data. Three factors influence the seismic sedimentary characterization and prediction of steep slope fans when employing SD. The ability of the ST to preserve phase is crucial for improving the imaging quality of the amplitude attribute. Sedimentary mechanisms control the sedimentary features of steep slope fans, impacting the imaging of seismic attributes. While channelized fan deltas can be better identified, unchannelized nearshore subaqueous fan deposits, which exhibit more heterogeneous sedimentary characteristics, present limitations. The unique volcanic evolution is another factor that impacts the image of the root-mean-square (RMS) attribute. Despite demonstrating excellent local adaptability in signal analysis, the S-transform cannot fully compensate for the combined effects of faults and sedimentary heterogeneity in nearshore subaqueous fans.

The Lower Ordovician Tongzi Formation containing abundant shoal sediments is the most promising stratum for the petroleum exploration in the Sichuan Basin. However, the current studies mainly focus on the central part of the Basin, the systematic analysis of the southeastern part with well-developed shoal facies is lacking. This paper aims to clarify the characteristics and genesis of the Tongzi Formation reservoir in Southeastern Sichuan Basin, following an analysis of sedimentary facies within the sequence stratigraphic framework. The research shows that the main types of reservoir rocks are oolitic, intraclastic and bioclastic dolostones. And the reservoir spaces consist mainly of intergranular (dissolved) pores, intercrystalline (dissolved) pores, intragranular dissolved pores and fractures. Among them, intergranular pores account for the highest proportion, which is followed by intragranular dissolved pores. In addition, most throats are necking and flaky which mainly connect intergranular and intercrystalline pores, respectively. The diagenetic sequence shows that penecontemporaneous karst well improved the porosity of the reservoir in the early-stage although the cementation and compaction reduced parts of pores. The reservoir formation is associated with the tectonic-depositional settings, diageneses and terrigenous contamination. Paleohighlands and submerged uplifts, forming in the early Ordovician amalgamation between Yangtze and Cathaysia blocks, accumulated shoal sediments as the material basis for the reservoir formation. Penecontemporaneous karst forming intragranular dissolved pores and the dolomitization aiding grainstones to resist the pressure solution are the key to increasing porosity and preserving pores. The absence of terrigenous contamination prevented intergranular pores from being strongly cemented, which resulted in the reservoir difference between the central and southeastern Sichuan Basin. The study can be used as a reference for the further exploration of Ordovician petroleum in the Sichuan Basin and other regions owning similar geological settings.

This study integrates field outcrop profiles, drilling cores, 2D seismic profiles, and 3D seismic data of key areas to analyze the Triassic tectonic-sequence stratigraphy in the Kuqa foreland basin, and investigates the impact of episodic thrust structures on sedimentary evolution and source rock distribution. (1) The Kuqa foreland basin has experienced stages of initial strong, weakened activities, relaxation and inactivity of episodic thrusting, resulting in the identification of 4 second-order sequences (Ehebulake Formation, Karamay Formation, Huangshanjie Formation, Taliqike Formation) and 11 third-order sequences (SQ1–SQ11) in the Triassic strata. Each sequence or secondary sequence displays a “coarse at the bottom and fine at the top” pattern due to the influence of secondary episodic thrust activity. (2) The episodic thrusting is closely linked to regional sequence patterns, deposition and source rock formation and distribution. The sedimentary evolution in the Triassic progresses from fan delta to braided river delta, lake, braided river delta, and meandering river delta, corresponding to the initial strong to the inactivity stages of episodic thrusting. The development stage of thick, coarse-grained sandy conglomerate reservoirs aligns with the strong to weakened thrust activities, while the source rock formation period coincides with the relaxation to inactivity stages. (3) Controlled by the intensity and stages of episodic thrust activity, the nearly EW trending thrust fault significantly thickened the footwall source rock during the Huangshanjie Formation, becoming the development center of Triassic source rock, and experienced multiple overthrust nappes in the soft stratum of the source rock, showing “stacked style” distribution. (4) The deep layers of the Kuqa foreland basin have the foundation and conditions necessary for the formation of substantial gas reservoirs, capable of forming various types of reservoirs such as self-generating and self-storing lithology, lower generating and upper storing fault block-lithology, and stratigraphic unconformity. This area holds significant importance for future gas exploration efforts aimed at enhancing reserves and production capabilities.

Deep to ultra-deep carbonate rocks have become a target for hydrocarbon exploration. The formation mechanisms of these deep to ultra-deep reservoirs are very complicated, and no consensus has yet emerged. This paper reports an investigation into the Middle Devonian Guanwushan Formation in the NW Sichuan Basin, China, which is a typical ultra-deep dolomite reservoir. Drilling-core and thin-section observations identified breccia matrix dolomite (MD) and interbreccia-filling dolomite (FD), of which the FD is commonly associated with sphalerite and barite. Geochemical analyses, including C and O isotopes, trace and rare earth element (REE) contents, and fluid inclusions, were conducted to investigate the origins of the different types of dolomite. Results indicate that the MDs generally retain the signature of syn-depositional seawater (relatively positive δ18O, low Fe and Mn, left-leaning REE patterns, and negative Ce anomalies), with involvement of meteoric water (relatively high Al, Ti and ΣREE). In contrast, the FDs were the diagenetic product of deep hydrothermal fluids (depleted δ18O, high Fe and Mn, and enrichment in MREEs), and the homogenization temperature of fluid inclusions is much higher than the normal burial geothermal temperature. The breccia dolomite reservoirs of the Guanwushan Formation were deposited as reef-core micro-facies and formed during the depositional to early diagenetic stages, and were the result of subaerial seawater dolomitization and meteoric water karstification. However, hydrothermal fluids subsequently modified the reservoir by cementation and filling. The Guanwushan Formation is a typical case of an ultra-deep carbonate reservoir that formed during the depositional to early diagenetic stages but was filled at the burial stage. Therefore, the favorable reservoir zones associated with deposition and early diagenesis should be the targets of future exploration. The findings of this study are expected to be of general significance for deep and ultra-deep oil and gas exploration in other regions and countries.

The Huayingshan tectonic belt in South China marks the tectonic boundary between the Xuefengshan intracontinental orogenic belt and the Sichuan Basin, and thus records interactions between the two domains. However, the processes of these interactions are still unclear due to the lack of knowledge about deformation patterns and timings. In this study, we present geometry and kinematics of the central Huayingshan tectonic belt in the Laogongqiao area (a critical location in the eastern Sichuan Basin) using field mapping, paleostress analysis and calcite U-Pb dating. Structural analysis indicates this belt is mainly featured by a southwestplunging anticlinorium and syntectonic northwest-verging imbricated thrust faults (D1) that are cut by a leftlateral transpressional fault (D2). Results of paleostress analysis and calcite U-Pb dating from fault zones further demonstrate two stages of deformation of the Huayingshan tectonic belt, in the Late Cretaceous (105-78 Ma) and Late Eocene-Early Miocene (38-19 Ma), respectively. The deformation scenarios are correspondingly interpreted to be associated with a) final termination of the northwestward propagation of the Xuefengshan intracontinental orogenic belt during the Cretaceous; and b) eastward extrusion, uplift and southeastward escape of the Tibetan Plateau during the Neogene. Thus, the Sichuan Basin, which lies between these two active areas, underwent compression and counterclockwise rotation during the Late Eocene-Early Miocene time. As a result of the conjugation, movement along the right-lateral Leibo fault led to partial division of the southern Huayingshan tectonic belt into a system of large folds, that in map view forms a splay diverging to southwest, by 19 Ma.

Table S1. Names of sections and boreholes in the Figure 1. This table comprise names of sections and boreholes which are used in the study and presented by numbers in the Figure 1. Table S2. Point-counting data of samples for the model sandstone petrology in the Xinjigu section. We obtain the modal framework grain compositons of 42 samples of medium- to coarse-grained sandstones from the Xinjigu section by point-counting standard thin sections according to the Gazzi-Dickinson method (Ingersoll et al., 1984). Table S2 documents the point-counting data of these sandstone samples. Table S3. Detrital zircon U-Pb dating from the measured Xinjigu section in the southwestern margin of the Sichuan Basin, western Yangtze region. We collected four sandstone samples from the lower Ordovician Hungshihyen Formation (XJG-102.4 and XJG-175) and upper Ordovician Taching Formation (XJG-806 and XJG-836) for zircon U-Pb dating. U-Pb geochronology of zircon was conducted by LA-ICPMS at the laboratory of carbonate sedimentary and diagenetic geochemistry, Southwest Petroleum University. Table S3 documents the data of detrital zircon U-Pb dating from these Xinjigu samples.

Amalgamation of the Yangtze and Cathaysia blocks in the context of Gondwana assembly in the early Paleozoic has been addressed for decades, but the far -field effects on the Yangtze Block during the amalgamation remain unclear. In this study, we outline the sequence stratigraphic framework of the Ordovician succession in the central-upper Yangtze Block and analyze provenance records in sandstone compositions, distributions, and detritus zircon U-Pb dating. The Ordovician succession in the central-upper Yangtze Block is subdivided into six third-order sequences, which were deposited mainly in a carbonate platform with restricted sediments in Tremadocian to early Floian stages, mixed terrigenous-carbonate deposits in mid-to late Floian stages, and open circulation sediments in Dapingian to middle Katian stages. These sequences show the central-upper Yangtze Block experienced syn-tectonic deformation with northeast-trending long-wavelength uplift and depression alternatively and the depocenter shifting from the east during Tremadocian to mid-Floian stages to the southwest in late Floian to early Hirnantian stages. Provenance data indicate that detritus in the Ordovician succession was mainly from the northern India and Kangdian paleohighland to the southwest of South China Block. Incorporating the depositional and deformation variations, we propose a retroarc foreland basin that was developed on the South China Block in response to final suturing between the South China Block and East Gondwana at Sanya suture zone. The South China Block was thus involved in the global tectonics of the Gondwana supercontinental cycle during the Ordovician.

课程思政建设是课程建设的重要内容之一,也是实现教书育人教育目标的重要途径之一.针对大学不同专业的特点如何进行与课程知识点有机融合的课程思政内容的建设,使其更有专业针对性是取得思政教育良好效果的关键之一.作为一个系统工程,课程思政建设过程中需充分结合专业与课程特点做好整体规划,并总结凝练出高质量、有针对性的专业课程思政元素,以确保专业课程的思政效果.在面向资源勘查工程专业的沉积岩与沉积相有关课程的课程思政建设过程中,结合专业的特点、课程的属性深入思考制定带课程思政元素的教学大纲,在大纲的指导下丰富完善课程思政的教学内容,并结合课程团队成员自身特色与优势,实施三者有机结合的课程思政实施方案,以期实现培养新时期具有强烈社会责任感和家国情怀、浓厚专业兴趣和强烈健康环保意识的地质勘探人才的目标.

通过岩心、岩屑和测录井资料,对四川盆地威远—高石梯地区二叠系栖霞阶层序地层特征进行了综合分析,指明了有利储层分布及控制因素.研究结果表明:①威远—高石梯地区二叠系栖霞阶可识别出2个Ⅰ型层序界面(梁山组底界面和栖霞组顶界面)和2个Ⅱ型层序界面(栖一段顶界面和栖二b段顶界面),据此将栖霞阶划分为层序SQ1,SQ2和SQ3,分别对应梁山组+栖一段、栖二b段、栖二a段.②研究区栖霞阶层序格架和平面分布特征显示,底部地层(SQ1)具有向沉积前古地貌高地超覆的特征,中上部地层(SQ2和SQ3)由沉积期地貌高地不断向低处迁移,呈现出"底超、中上部迁移"的层序充填规律.③研究区SQ2和SQ3高位体系域沉积时期,古地貌高地和坡折带发育厚度大、横向连续性较好的丘滩复合体,奠定了储层发育的物质基础,该时期海平面频繁升降,丘滩复合体发生高频暴露岩溶作用,使得储集性能得到改善,叠加白云岩化作用后形成抗压溶骨架,有利储层发育.④沉积相和岩溶作用控制了白云岩薄储层的发育和分布,栖霞阶沉积期高地和坡折带为下一步勘探的潜力区.

鄂尔多斯盆地奥陶系马家沟组广泛发育岩溶角砾岩,结构特征复杂.近期研究发现,这些角砾岩的组构和分布特征难以能单纯地用经典的风化壳岩溶模式解释,各类角砾岩的成因机理值得进一步探究.文中基于大量岩心及薄片观察,对苏里格气田东区奥陶系马家沟组上组合不同层位角砾岩进行归纳和判识,明确其空间展布和序列结构特征,分析形成机理.研究发现:(1)根据成因与发育环境,苏格里气田东区奥陶系马家沟组上组合角砾岩可划分为5类,分别是近原地解离角砾岩(B1)、近地表堆积角砾岩(B2)、洞穴堆积角砾岩(B3)、洞顶(壁)碎裂角砾岩(B4)和坍塌角砾岩(B5),它们具有纵向多层叠置、横向可对比的"准层状"特征;(2)不同类型角砾岩的纵向配置和演化与周期性的向上变浅沉积序列和暴露溶蚀有关,共归纳为3种类型,即B1主发育型、B2-B3-B4组合发育型、B5主发育型;(3)准层状角砾岩形成于早成岩期,受控于古地貌起伏背景下的高频海平面变化,由暴露溶蚀透镜体横向迁移连片和纵向多旋回叠置而成.研究结果不仅有助于了解鄂尔多斯盆地马家沟组多样化的岩溶角砾岩特征与成因,也为白云岩早成岩期岩溶研究提供了新的素材.

The reservoir rocks in the volcanic strata of the Jilin oil field are characterized by great complexity and diversity in composition and structure of lithology. To enhance the rate of lithology identification in subsurface is very laborious. However, lithology identification is often ignored in quantitative studies, though it is the basis for reservoir characterization. In this paper, an ensemble learning algorithm named gradient boosting decision tree (GBDT) was used to establish the classification model for the volcanic lithology identification of the Lower Cretaceous Yingcheng Formation in the Songliao Basin, NE China. At the same time, support vector machine (SVM), logistic regression (LR) and decision tree (DT) classification models were also adopted in contrast with the classification accuracy of GBDT model. Subsequently, the optimal key parameters for each model were determined by employing validation curves and GridSearchCv. These results indicate that the GBDT model is superior to the single classifier and can accurately distinguish the lithologic interface of breccia tuff and rhyolite. Moreover, it also has better recognition ability for thin layer. It was concluded that the ensemble learning algorithm GBDT has significantly enhanced the accuracy of lithology identification and can be used as a lithologic identification technology.

野外实践教学是学生德智体美劳培养的重要途径,在野外教学中开展课程思政是课程建设、人才培养质量提升的抓手之一.为保障国家能源战略安全、培养新时期地质类专业人才,在OBE理念指导下,针对地质类专业人才培养定位,以沉积相野外实习为载体,围绕培养学生的爱国情怀、专业自信、科研思维与创新意识、安全环保意识等方面进行了针对性的思想政治教育,学生在培养实践能力的同时,也得以全方位提高思想认识,坚定了为祖国找油气的信心.

In deep to ultra-deep sandstones, natural open fracture patterns strongly influence the directions, magnitudes, and heterogeneities of fluid flow. We present an analysis of the natural fracture patterns, critically-stress state, and productivity of 35 wells in the Keshen and Dabei gas fields of the Kuqa foreland thrust belt. Our results show that reservoir performance is governed by the critical stress that acts on existing fractures to enhance their permeability. There is a good correspondence between the critically-stressed fractures and the natural open fractures in cores. These open fractures have patterns of barren cement, quartz bridges, and slickensides. Barren cement and quartz bridges indicate the preservation of permeable fractures, while the slickensides indicate shear reactivation. Barren fractures developed due to extension at the late stage of structural activities. Quartz bridge can prop up fracture walls to preserve porosity and permeability when compression. Shear reactivations consist of strike-slip and dip-slip, which broke the gypsum and calcite seal. Shear-reactivated fractures could reflect stress state transition from thrust regime to strike-slip regime during rapid burial. Combined with the analysis of fracture morphologies and kinematics, we indicate that open fractures development may relate to folding and fault reactivation. Besides, our case indicates that the E-W open fractures in the Keshen field and NE-SW open fractures in the Dabei field are not consistent with the direction of modern-day maximum horizontal compressive stress (σHmax). We conclude that the quartz bridge and shear reactivation govern the persistence of open fractures in tight and ultra-deep sandstones, even if the open fractures are perpendicular to σHmax.

Middle Triassic marine carbonate successions deposited on the northwestern Yangtze passive continental margin preserve information about the initial collision between the South China Block (SCB) and the North China Block (NCB). We extracted data from 51 boreholes and 23 outcrops of the Middle Triassic Leikoupo Formation to interpret the spatio-temporal stratigraphic framework, depositional transition, and contractional deformation in the Upper Yangtze region. The sedimentological analysis indicates that the Leikoupo Formation may be divided into nine successions, which were overall deposited in restricted-evaporative marine platform and lagoon environments during the Anisian. From the thickness distributions of each sequence, the Upper Yangtze region is shown to have experienced northwest-southeast horizontal compression and vertical uplift, which drove northwestward migration of the coeval depocenters and marine regression. We propose that the marine deposits of the Leikoupo Formation and the contemporary paleo-uplifts can be considered products of the forebulge and backbulge depozones of a peripheral foreland basin. The Early Triassic passive continental margin in the Upper Yangtze region had thus transformed into a peripheral foreland basin in response to the collision between the SCB and NCB by the Anisian. The northwestward retreat of seawater with synchronous growth of the forebulge further supports the oblique suturing between the two rotating blocks. In response to continuous basin-ward thrusting of the Micangshan-Daba Shan and Longmen Shan belts, new transpressional flexural subsidence developed, leading to the formation of terrestrial deposits in the Late Triassic basin.

碳酸盐组分与陆源碎屑物的混合沉积(Mixed siliciclastic-carbonate sedimentation)在古气候、古环境重建方面具有重要作用,近年来受到国内外学者广泛关注.寒武纪沧浪铺早期,上扬子北缘靠近汉南古陆的浅水环境中混合沉积广泛发育,以石英、岩屑等陆源碎屑与碳酸盐的层内混合和间互沉积为主要特征.研究表明,以碎屑颗粒占主导的混积岩(郭家坝组顶部及阎王碥组底部)表现为灰质粉砂岩—泥岩互层,以及灰质粉砂岩—灰质泥岩的间互沉积,形成于陆棚和潟湖等相对低能环境.以碳酸盐占主导的混积岩(仙女洞组)主要发育"碳酸盐岩—混积岩"和"混积岩—混积岩"的沉积序列,表现为:1)泥晶灰岩—灰质泥岩互层,2)灰质岩屑细砂岩—砂质鲕粒灰岩互层,以及3)灰质细砂岩→砂质鲕粒灰岩→亮晶鲕粒灰岩的旋回,形成于台缘斜坡及台地边缘等高能环境.在沧浪铺期海退背景下,川北地区仙女洞组以碳酸盐占主导的混积体系具有"近源"沉积特点.陆源碎屑通过三角洲—河流入海口进入浅海环境,并经过沿岸流和波浪的搬运,对台地边缘相带的微生物丘、古杯丘和鲕粒滩为主的碳酸盐工厂造成影响,形成相缘渐变混合和原地沉积混合的混积类型,其发育与当时气候条件、陆源供给量、水动力条件及生物作用有关.而台缘斜坡—陆棚环境中,风暴、浊流等间断性事件对混积体系起着主要作用,易形成事件突变混合.因此,厘清以唐家河剖面为代表的川北寒武系混积特征及分布发育情况,对于认识上扬子地区北缘寒武纪早期古地理背景、古环境演化,以及混积岩储层发育特征等方面具有促进作用.

野外实践是面向油气勘探的工程类专业人才培养关键环节之一,在野外教学中以OBE理念为指导,针对野外重点教学内容进行了野外翻转课堂的设计与实践.在精心选取翻转课堂教学内容的基础上,组织落实课前、课中、课后三个教学阶段.通过此过程训练,学生的科研思维得以启发,研究能力得以提高,团队意识得以加强.

LA-ICP-MS zircon U-Pb isotopic data for the sandstone samples from the Middle to Upper Triassic successions in the northern Sichuan Basin and Zigui Basin. Four sandstone samples were collected from the lowermost Upper Triassic strata that unconformably overlie the Leikoupo Formation for detrital zircon analysis. The Upper Triassic Xujiahe Formation is generally considered to mark the transition from a marine platform to a terrestrial basin on the upper Yangtze Block (Meng et al., 2005). In the Guangyuan and Wangcang areas, we collected three sandstone samples from the lower portion of the Xujiahe Formation. At the Ma’antang train station, we collected one sandstone sample from the Ma’antang Formation, which is a transitional deposit from marine to terrestrial environments in front of Longmen Shan. The analysis was conducted with laser ablation inductively coupled plasma mass spectrometer (LA-ICPMS) at the Key Laboratory of Continental Collision and Plateau Uplift, Chinese Academy of Sciences (CAS). Analytical methods were described in detail by Cai et al. (2012) and are briefly described here. A total of 362 zircon grains from 4 samples produced data of sufficient precision for geochronological interpretation.