The Late Jurassic climate in Central Asia was arid. The existence of the eolian deposits of the Junggar Basin in the southern Central Asia is contentious. In order for a better understanding of these eolian deposits,here we conducted detailed sedimentary investigations on the Upper Jurassic strata of the southern Junggar Basin. The eolian deposits of the Kalazha Formation underlie the Jurassic-Cretaceous unconformity. The sedimentary records extend ~100 km from east to west. The thickest eolian deposits are ~250 m in thickness. The Jiangong mine section exhibits approximately 10-meter-thick eolian deposits and several stages of gravely braided river deposits. The eolian sands show high compositional and textural maturity and are mainly composed of saltation grains. The eolian dune deposits show large-scale,high-angle cross-bedding and inverse-grading. The eolian sheet deposits develop low-angle oblique and parallel laminations with good lateral continuity. The river sands and coeval eolian sands have similar grain-size distribution and sediment sources. The paleo-wind direction is orthogonal to the river flow direction. These suggest that the eolian sands were sourced from river sands and the river sands were partly from the eolian dune field. The eolian-fluvial system was controlled by the Late Jurassic aridification and tectonic activities of the Tianshan orogen. The aridity caused the decrease of sediment supply and the rise of the base level,which caused the expansion of the eolian deposits. The tectonic reactivation of the Tianshan led to dropping of the base level,the formation of Kalazha alluvial conglomerates. The Jurassic to the Early Cretaceous sedimentary environments of the southern Junggar Basin witnessed two important changes: the marshy fluvial-lacustrine sedimentary system changed to eolian-alluvial system,and subsequently evolved to lacustrine-delta system. These climatic changes may be related to the Jurassic true polar wander and block of the moisture by the paleo-Tianshan.

Recent significant breakthroughs in natural gas exploration have been achieved in the shoal-facies dolomite reservoirs of Member 2 of the Middle Permian Maokou Formation in the Sichuan Basin. The distribution of these dolomite reservoirs is fundamentally controlled by the dynamic interplay between sedimentary evolution and tectonic-sedimentary differentiation during the Maokouan stage under the influence of the Emeishan mantle plume. Integrating field outcrops,drilling data,well logs,and conodont biostratigraphy,this study establishes the correlation between lithostratigraphic and biostratigraphic frameworks in the central-northern Sichuan Basin,investigates the coupling mechanism between Emeishan plume activity and Maokouan sedimentary evolution,and precisely constrains the timing of tectonic-sedimentary differentiation. Key findings include: (1)Pre-eruptive crustal uplift induced by the Emeishan mantle plume established a SW-high/NE-low carbonate ramp during the deposition of Member 1 to Lower Member 2 of Maokou Formation. Subsequent plume-driven tectonic activity transformed the ramp into a differentiated platform system during Upper Member 2 deposition,forming the Mianzhu-Pengxi intraplatform depression,Guangyuan-Kaijiang shelf,and the 400 km-long Jian'ge-Fengdu platform-margin belt. (2)Tectonic-sedimentary differentiation initiated within the Jinogondolella altudaensis conodont zone(263-262 Ma),with subsequent intensification of plume activity triggering northward expansion of the Guangyuan-Kaijiang basin facies. (3)Subaqueous volcanic eruptions likely occurred in southwestern Sichuan during the Maokouan stage,potentially developing an E-W trending intraplatform depression along the Dujiangyan-Jianyang area. (4)Prototypes of the Mianyang-Wusheng shelf and Kaijiang-Liangping intraplatform trough,characteristic of the Late Permian Changhsingian stage,were established no later than the depositional stage of the Upper Member 2 of Maokou Formation.

The southern Sichuan Basin represents the depocenter of the Silurian Longmaxi Formation,a regionally significant hydrocarbon source rock. The overlying Shiniulan Formation limestone has significant advantages for near-source hydrocarbon accumulation. However,no significant breakthrough has yet been achieved in the exploration of large-scale reservoirs in this interval. The study focuses on the geological and sedimentary characteristics of the Shiniulan Formation. Using drilling,core,outcrop,and 3D seismic data,the palaeogeomorphic framework and sedimentary evolution were reconstructed. The results show that the study area can be divided into three geomorphic units: the southern high zone,the central depression,and the northern high zone. These geomorphic features strongly control the spatial distribution of sedimentary facies within the Shiniulan Formation. The high zones are characterized by carbonate platform and reef deposits,which are the main targets for oil and gas reservoir prediction. The central depression dominantly consists of mudstone and mixed shelf deposits. The uplifts of the Chuanzhong and Qianzhong during the Early Silurian period shaped the palaeogeomorphy and sedimentary pattern of the Shiniulan Formation. The continuous activity of the Chuanzhong uplift and the enhanced terrestrial input from the Xuefeng ancient land and the falling sea-level led to the demise of the carbonate platform. These findings offer a theoretical framework and predictive insights for future hydrocarbon exploration and development in the Shiniulan Formation.

The shale of the Lower Cambrian Niutitang Formation is an important hydrocarbon source rock in the Middle and Upper Yangtze region. However,significant inconsistencies remain regarding the stratigraphic division and framework establishment of the Niutitang Formation in the Middle and Upper Yangtze region. Moreover,sequence stratigraphic studies focused specifically on the Niutitang shale are still limited. In this study,the stratigraphic framework and sedimentary evolution of the Lower Cambrian Niutitang shale in western Hubei Province were systematically analyzed using an integrated approach incorporating field outcrop observations,drilling core data,conventional and spectral logs,and geochemical proxies. Two third-order sequences are recognized within the Niutitang Formation shale in western Hubei Province. The first(Niu 1 Member)and second(Niu 2 Member)members each constitute a third-order sequence composed of a Transgressive Systems Tract(TST)and a Highstand Systems Tract(HST). Sequence stratigraphic correlation enabled the reconstruction of depositional environments and relative sea-level fluctuations,revealing four evolutionary phases during the Early Cambrian: a fluctuating transgressive stage,a fluctuating regressive stage,a rapid transgression,and a gradual regression. A comprehensive depositional model for the Niutitang shale is established,providing a theoretical foundation for predicting favorable reservoir intervals and guiding future shale gas exploration in the Central and Upper Yangtze region.

In recent years,sublacustrine fans have emerged as a prime focus for oil and gas exploration in the Ordos Basin due to their immense potential. However,their development is influenced by multiple factors,leading to distinct sedimentary evolution patterns under varying geological settings. This study focuses on the sublacustrine fan in the Chang 7 Member of Yanchang Formation in the Ordos Basin. By integrating core,well logs,and seismic data,a detailed analysis of the sedimentary evolution of the Chang 7₁ sequence unit's sublacustrine fan in the Qingbei area was conducted within a high-resolution sequence framework. The results show that the Chang 7₁ sequence unit can be systematically divided into five distinct fifth-order sequence units,based on lithological discontinuity surfaces within the fourth-order sequence. Notably,the crucial fifth-order sequence units,7₁-5 and 7₁-4,can be further subdivided into 10 sixth-order sequences. The present study successfully distinguished various sedimentary units within the sublacustrine fan,including gravity flow channel,channel-levee complex,levee,lobe,and lobe edge. Given the sedimentary background,the sublacustrine fan in the study area is interpreted to be mainly sourced from the braided river delta front. The results indicate that during periods of lake-level fall under warm and humid climatic conditions,increased terrigenous clastic input enhanced sediment suppy from the braided river delta front,and the accommodation space of the lake basin decreased,facilitating northeastward progradation of the sublacustrine fan,with expanding depositional lobes showing distinct lateral migration patterns.

To investigate the spatial distribution and depositional patterns of fine-grained lithofacies in the Chang 7₃ submember of the Triassic Yanchang Formation in the Longdong area of Ordos Basin, a series of flume simulation experiments were conducted. The experimental design consisted of 13 rounds grouped into three depositional stages. Quantitative data on the fine-grained depositional processes were acquired using a 3D scanner, 4K high-resolution video capture, and flow velocity sensors. The experimental results show that: (1)Four main lithofacies were identified in the experiments: tuff, fine- to very fine-grained sandstone, siltstone, and mudstone. Based on depositional environment characteristics, nine lithofacies assemblage types were recognized; (2)From the sediment source to the deep lacustrine area, a progressive fining trend in lithofacies is observed. Hydrodynamic energy decreases basinward, leading to reduced thicknesses of tuff and sandstone deposits and increased accumulation of mudstone; (3)The paleomorphology, hydrodynamics and material source control fine-grained sedimentary lithology distribution with remarkable regularity. The typical rock phases in the deep lake area are thick mudstone interbedded with tuff and thick mudstone interbedded with thin layer of siltstone; Hydrodynamic regime governs the types of fine-grained lithofacies assemblages. The scale of their development is influenced by the strength of sediment supply. In addition, the nature of paleogeomorphic units affects water energy distribution and sediment transport pathways, ultimately determining the spatial configuration of lithofacies assemblages. The experimental results provide a conceptual model of fine-grained deposition under deep-water conditions, offering valuable guidance for shale oil and gas exploration in the Chang 7₃ submember of the Yanchang Formation in the Longdong area, Ordos Basin.

Arid distributive fluvial systems (ADFS) have attracted considerable academic interest due to their large spatial extent and potential for hydrocarbon reservoir development. This study focuses on the arid distributive fluvial system, analyzing its dynamic evolution, depositional characteristics, and internal configuration through flume experiments. The findings are as follows: (1) In arid distributive fluvial systems, lobes act as the fundamental depositional building blocks, exerting primary control over system formation and evolution. (2) Based on their formation processes, lobes can be categorized into three types: lateral, oscillating, and accretionary. In cross-sectional view, these types display characteristic stacking patterns: lateral, irregular, and vertical, respectively. Lateral lobes develop primarily along the fan margins and are characterized by large area, length, and width, with high aspect and width-to-thickness ratios and a lobate geometry. Oscillatory lobes occur at the fan front, sharing similar dimensions and morphology. In contrast, accretionary lobes are smaller, develop near the fan apex, and exhibit lower aspect and width-to-thickness ratios, with a tongue-shaped geometry. (3) Throughout the evolution of the arid distributive fluvial system, a cyclical process of 'channel incision-lobe front accumulation-lobe lateral migration-lobe backward migration-channel re-incision' is observed, demonstrating regularity and periodicity at various stages of the system's evolution. These findings enhance the understanding of sedimentary processes, internal architectures, and spatial evolution within arid distributive fluvial systems, and offer guidance for reservoir prediction in analogous depositional settings.

The 5^th International Congress on Ichnology was successfully held in Florianopolis,Brazil,from April 14^th to 19^th,2024. A total of 128 abstracts were collected. Based on oral presentations,posters,geological field work,and thematic discussions,new progress and applications of ichnology theory were mainly concentrated on five aspects: (1)traditional ichnology,detailed study of trace fossils and ichnotaxonomy,exploring behavior of the trace-makers,and reconstructing palaeoenvironments and ecosystems;(2)quantitative analysis of trace fossils by interdisciplinary approaches;(3)research on tetrapod animals and dinosaur footprints in South America;(4)biological disturbance in the transformation of the oil and gas reservoir;(5)further development of neoichnology technologies.

Crabs serve as ecological engineers capable of sensitively reflecting and modifying sedimentary and ecological environments in which they reside. The sedimentary environment of the Pearl River Delta Plain is highly complex,which is characterized by a diverse and abundant crab population. This paper focuses on investigating the distribution and compositional characteristics of different crab species within the region,as well as their significance in indicating paleoenvironments. A total of 92 sampling points in the Pearl River Delta Plain were established to collect water samples,soil samples,and biogenic submerged burrow cores. Observations and photographic documentation were conducted to record the distribution and characteristics of crab traces at each sampling point. Subsequently,sedimentary environments and crab traces within the study area were analyzed using methods such as salinity measurement,granulometric analysis,CT scanning,and three-dimensional reconstruction. Key findings include: (1)The predominant crab species identified were Orisarma dehaani and Orisarma sinense from the family Grapsidae,Grapsoidea,and Paraleptuca splendida from the family Ocypodidae,Ocypodoidea. Crab traces included tracks,fodinichnia,waste trails,and burrows,with most burrows exhibiting I-and J-shaped configurations and a few Y-shaped structures. (2)Crab traces were predominantly distributed in intertidal zones influenced by tides,with the highest abundance observed in estuarine areas,and relatively fewer traces in diversion channels and coastal wetlands. (3)Through analogy,it was determined that the morphological characteristics and depositional environments of crab traces resemble those of the trace fossil Psilonichnus,which is primarily found in shallow marine firmground environments. Additionally,trace phases associated with crab traces include Glossifungites,Psilonichnus,and Skolithos. This study contributes modern sedimentological data for the Pearl River Delta Plain,reveals the paleoenvironmental significance of crab traces,and provides critical evidence for geological and ecological research.

The well Pingqiao 1 in the eastern Sichuan Basin achieved commercial gas flow in the Cambrian Xixiangchi Group,demonstrating significant exploration potential in this stratigraphic unit. Based on outcrop,core,thin section,logging and well-log data,the development and distribution of shoal reservoir in Xixiangchi Group has been studied by reservoir geology method. The results show that: (1)The tidal flat cycle,peritidal cycle and subtidal cycle are identified. Shoal deposits predominantly develop in the peritidal and subtidal cycles. Peritidal shoals are located at the middle-upper part of highstand system tracts where shallow-water conditions interacted with periodically exposed events,resulting in penecontemporaneous dissolution. Subtidal shoals formed in transgressive system tracts(TST)and lower HST high-energy zones,interfacing with low-energy deep subtidal environments without significant exposure-related dissolution. (2)The shoals in the eastern Sichuan Basin are developed in the eastern margin of the low-lying area of the platform,and are dominated by doloarenite and silt-fine crystal dolomite lithofacies. Reservoir spaces primarily consist of intergranular(dissolved)pores and intercrystalline(dissolved)pores. The average porosity and permeability are 3.24% and 1×10^-3 μm³,respectively,showing the characteristics of low porosity and permeability reservoirs. (3)The development of shoals in the peritidal cycle is affected by the paleogeomorphology,and whether it is dissolved by atmospheric fresh water in the quasi-contemporaneous period is the key to reservoir formation.

The physical properties of shale reservoirs are crucial to the enrichment mechanism of shale oil and gas. This study focuses on investigating the reservoir's physical properties and the key factors controlling various lithofacies of continental shale in the Jurassic Dongyuemiao shale in the eastern Sichuan Basin. On the basis of lithofacies division,the research employs core observation,scanning electron microscope,low-temperature nitrogen adsorption,and other methods to analyze the reservoir space type,physical properties,and the primary controlling factors. The study findings reveal that: (1)The Dongyuemiao Member shale in the eastern Sichuan Basin are primarily composed of clay minerals and quartz,followed by calcite,and minor amounts of feldspar,dolomite,pyrite,and rhodochrosite. Four main lithofacies are identified in the study area: high-medium total organic carbon(TOC)argillaceous shale(Ⅰ₂),medium TOC and TOC bearing mixed shale(Ⅱ₁),medium-low TOC silt(argillaceous)mixed shale(Ⅱ₂),and low TOC and TOC bearing argillaceous siltstone(Ⅲ₂). (2)The shale reservoir space is mainly composed of micropores and microfractures. The micropores are dominated by intergranular pores between clay minerals,followed by pores within organic matter and,locally,shell dissolution pores. Microfractures mainly include bedding fractures and edge fractures around shell fragments. (3)High organic matter abundance(>1%),high content of clay minerals(>40%),and moderate carbonate mineral content(8%~12%)in the shale of the study area are conducive to pore development. In contrast,high quartz and feldspar mineral content(>50%)and either excessive or insufficient carbonate mineral content(>12% or <8%)hinder shale pore development. (4)Among the lithofacies types,the medium-low TOC silty(argillaceous)mixed shale(Ⅱ₂) is the most favorable for reservoir development,followed by high-medium TOC argillaceous shale(Ⅰ₂). The medium TOC and TOC bearing mixed shale(Ⅱ₁) is less favorable,while the low TOC and TOC bearing argillaceous siltstone(Ⅲ₂) is the least favorable. Based on the vertical distribution of lithofacies,the middle to upper intervals of the Dong 2 sub-member are identified as the most favorable reservoir development zones in the study area.

This study investigates the genetic mechanisms of marine organic-rich shale reservoirs through an integrated analysis of mineral composition,total organic carbon(TOC),porosity,gas content,and sedimentary paleogeomorphology in the Upper Ordovician Wufeng Formation(O₃w)to Lower Silurian Longmaxi Formation(S₁l₁)within the Changning area,southern Sichuan Basin. The results show that: (Ⅰ)Carbonate minerals and siliceous minerals are mainly developed in the O₃w,and the TOC,porosity and gas content of the shale are relatively poor;The shale in the bottom of S₁l_1^1 is dominated by siliceous minerals,and its TOC,porosity and gas content are the best. The upper S₁l_1^1 is dominated by clay minerals,and its TOC,porosity and gas content are poor. (Ⅱ)Marine shale reservoirs of O₃w and S₁l_1^1 can be divided into three categories: matrix-porosity reservoirs(dominant in O₃w,avg. porosity 3.1%),clay-fracture reservoirs(prevalent in lower S₁l_1^1,avg. porosity 5.8%)and organic-porosity reservoirs(characteristic of upper S₁l_1^1,avg. porosity 2.3%). Organic-porosity reservoirs represent the optimal marine shale gas reservoirs,characterized by high porosity and excellent gas-bearing capacity. (Ⅲ)The pre-depositional paleogeomorphic pattern of the Longmaxi Formation is drawn based on the bottom interface of the lower Permian Liangshan Formation by the residual thickness and compensation thickness impression method. The comparative study of reservoir characteristics and paleogeomorphic pattern in the bottom of S₁l_1^1 proves that the paleouplift controls the high-quality source rocks,the slope area controls the high-quality reservoirs,and the distribution of brittle minerals is controlled jointly by the paleouplift and terrigenous input. Comprehensive analysis shows that the high quality shale gas reservoir mainly develops in the paleogeomorphic slope area. This systematic approach advances exploration strategies for marine shale reservoirs and enhances theoretical understanding of shale gas enrichment mechanisms in southern China.

The Mesozoic superimposed basin in the Hexi Corridor is characterized by complex tectonic evolutions and variable sedimentary systems. The stratigraphy of these hydrocarbon-bearing basins has undergone multiple phases of burial and tectonic uplift,and hydrocarbon reservoirs exhibit diverse diagenetic alterations and strong heterogeneity. Therefore,the study of reservoir diagenetic characteristics and the associated sedimentary and diagenetic controls is essential for the successful exploration of oil and gas fields. This study focuses on the diagenetic mineralogical characteristics and evolution of the Middle Jurassic Lower Xinhe Formation,based on a range of analytical techniques,including optical microscopy,scanning electron microscopy,and geochemical tests. Moreover,the impacts of sedimentary and diagenetic characteristics on reservoir quality are investigated. The study demonstrates that the target layers are characterized by braided delta front and gravity flow deposit,which are dominated by arkoses and lithic arkoses. The variations in pore space types and physical properties of sandstone reservoirs are determined by the combined influence of microfacies,burial diagenetic alterations and uplift-related dissolution. In detail,the medium- to thick-bedded sandstones of subaqueous distributary channel facies at the delta front are characterized by strong dissolution modification and limited secondary authentic precipitations. These reservoirs typically exhibit low porosity and medium permeability. The medium-to thin-bedded sandstones of gravity flow channel and mouth bar facies are characterized by a considerable quantity of detrital feldspar and fragments,as well as high content of ductile clay-rich matrix. Furthermore,the dissolution pores are filled by abundant authigenic albite,silica cements and clay minerals. Consequently,the sandstones exhibit tight reservoir characteristics,with low porosity and low permeability.

The intricate tectonic evolution,coupled with diverse sedimentary environments and highly variable lithologies,results in strongly heterogeneous reservoirs in the Santai Formation of the Zhanhua sag,making reservoir quality prediction particularly challenging. This highlights the critical importance of accurately identifying and classifying diagenetic facies for effective reservoir evaluation. Traditional supervised learning methods for whole-well diagenetic facies identification are limited by the availability of training samples and thus often impractical in data-scarce scenarios. To address this,an unsupervised learning approach constrained by single-factor analysis is proposed for the logging-based identification of diagenetic facies. By integrating parameters such as apparent compaction rate,cement content,porosity,and fracture density,four diagenetic facies were identified: dense compaction facies,carbonate-cemented facies,dissolution-fracture facies,and weakly dissolved facies with unstable components. Four diagenesis-sensitive logging curves—GR(natural gamma),AC(acoustic travel time),DEN(density),and RD(deep lateral resistivity)—were selected as inputs for the unsupervised clustering algorithm. The clustering ranges of these curves were individually constrained to establish a reliable correlation between logging responses and diagenetic facies. Calibration of logging facies with diagenetic facies was conducted using core data,including thin-section analysis of cast samples,allowing for regional-scale identification and classification of diagenetic facies. The results show that the dissolution-fracture facies and weakly dissolved facies with unstable components represent the most favorable diagenetic facies for reservoir development. These are associated with relatively high porosity and permeability and are mainly distributed in coarse-grained rocks such as conglomeratic sandstones and,while the weakly dissolved facies with unstable components are mainly distributed in fine-grained rocks like siltstone. The accuracy of the proposed method was validated through comparisons with blind wells,demonstrating its effectiveness in non-cored intervals. This approach provides a novel method for predicting reservoir diagenetic facies and offers practical implications for the evaluation and prediction of high-quality reservoir zones in data-limited settings.

The identification and prediction of shale lithofacies are crucial for identifying favorable intervals(“sweet spots”)in shale oil and gas reservoirs. In the absence of core data,logging data plays a key role in lithofacies analysis at the single-well level. By applying the XGBoost algorithm,useful lithofacies information can be extracted from multidimensional logging data,enabling effective prediction of shale lithofacies in individual wells. In this study,the XGBoost machine learning method,a supervised learning algorithm,is used to build a predictive model based on conventional logging datasets. First,a lithofacies classification scheme tailored to the specific study area is established,which captures the variability in shale lithofacies identification. The boundaries of mineral compositions and TOC content for different lithofacies types are then determined using statistical proportion analysis. During model construction,care must be taken to eliminate redundant variables,as highly correlated features may provide overlapping information and cause overfitting. XGBoost's grid search approach allows comprehensive parameter tuning. Multiple rounds of optimization should be conducted,with the search range gradually narrowed to determine the optimal parameter set. Using the Zanzijing block in the Songnan area as a case study,five major shale lithofacies types are defined based on mineral composition,sedimentary structures,and TOC content. During variable selection,for instance,only one of the highly correlated LLD and LLS logs is retained,which results in a model accuracy improvement of approximately 4%. After feature selection and parameter tuning,the final model achieves a lithofacies prediction accuracy of up to 90.03%.

At the bottom of the Upper Permian Longtan coal measures in eastern Yunnan and western Guizhou,there is a Nb-Zr-REY-Ga type cirtical metal ore layer with a cumulative thickness of several meters and characterized by natural gamma positive anomalies. By means of seismic work and traditional wave impedance inversion,sandstone and mudstone can be effectively distinguished,but limited by the small difference of wave impedance,the ore layer can not be identified. In order to construct a fine geophysical exploration technology for the ore layer,based on logging and seismic data,this paper takes gallium(Ga)element in the ore layer as an example(gamma value>2.0 API when the critical industrial grade is 50 μg/g),and uses the information statistical weighting method and the natural gamma data of the ore layer to reconstruct the longitudinal wave velocity curve,so that the calculated wave impedance curve of the ore layer signal is enhanced by about 120%,and the ore layer is constrained within the reconstructed wave impedance value range of >16 000 g/cm³·m/s,which solves the technical problem of identifying key metal ore layers by using wave impedance curve. On the seismic section inverted by the reconstructed wave impedance data,the boundary of the ore layer is clear and the lateral traceability is good. Through drilling verification,the average error of the thickness of the ore layer predicted by seismic inversion is 17.6%. It shows that the seismic inversion using the reconstructed wave impedance data can effectively identify and track the ore layer,and achieve the purpose of fine detection of the ore layer. This technical method has good application value and prospect for fine exploration of cirtical metal ore layers in coal measures with abnormal logging.

In situ stress significantly controls the quality of deep and ultra-deep tight sandstone reservoirs. It is important to clarify the stress-controlled storage effect for the comprehensive evaluation and prediction of deep and ultra-deep tight sandstone reservoirs. In this paper,basic characteristics of the Cretaceous Bashijiqike Formation in the Zhongqiu area of Kuqa Depression are revealed through analysis of cores and thin sections,the logging evaluation of in situ stress is realized,and the control of in situ stress on reservoir quality is clarified. The results show that the reservoir is mainly made of medium-fine sandstones,which is dominated by primary intergranular pores,with less secondary pores and occasional fractures. The fracture surface morphology is picked up by image logging,and the logging calculation of fracture parameters is realized. Evaluation of in situ stress is completed through logging data,and the coupling control relationships between in situ stress,and matrix pores and fracture parameters are revealed. The reservoir classification and evaluation of the Bashijiqike Formation are realized by combining physical parameters with in situ stress. High-quality reservoirs are mainly developed in fractured zones and intervals with low in situ horizontal stress differences. Through logging evaluation of in situ stress combined with calculation of reservoir parameter,the reservoir quality classification evaluation and high-quality reservoir logging prediction can be realized. The research results may provide technical support for the comprehensive evaluation of deep and ultra-deep tight sandstone reservoirs and the prediction of favorable zones.

Since the concept of New Quality Productive Forces was proposed,it has been interpreted from various disciplinary perspectives and has a close connection with the basic discipline of palaeogeography. In the era of digital intelligence,the development of New Quality Productive Forces and palaeogeography have a mutually reinforcing effect. Development of New Quality Productive Forces provides new means and methods for palaeogeography studies. Palaeogeography studies serve the investigation of rare mineral resources and provide support for the progress of strategic emerging industries and future industries in terms of energy resource security and other aspects. The integration,analysis and application in digitalization of palaeogeographic big data, can improve the working efficiency and decision-making level of geological workers,and at the same time,it provides talent reserves for the development of New Quality Productive Forces.

This article integrates multi-source dataset,including local chronicles,compiled materials,and historical material online platform,to extract information county-level occurrences,temporal characteristics,and disaster triggers of famines in Shaanxi Province during the Ming Dynasty(1368-1644 AD). Through semantic quantification,statistical analysis,and famine index construction,we reveal the spatiotemporal patterns of famine and identify key disaster drivers. The results are as follows: (1)Famines in Shaanxi Province during the Ming Dynasty exhibit distinct temporal patterns and monthly/seasonal variations,with three phases: 1368-1420 AD,1421-1600 AD,and 1601-1644 AD. The third phase(1601-1644 AD)shows the highest severity and spatial extent,with famines clustered in July and February but distributed across seasons. Periodic analysis indicates famine periodicity correlates with solar activity cycles.(2)Regional disparities are evident: Guanzhong(central Shaanxi)records the highest frequency,whereas northern and southern Shaanxi suffer greater severity. Southern Shaanxi exhibits the strongest clustering.(3)Drought is the dominant single-factor trigger(SF),while drought-insect co-occurrence prevails among dual factors(DF). DF-induced famines are more severe than SF. The primary drivers are droughts, locust infestations, and floods. Regional variations align with environmental contexts: northern Shaanxi is drought-dominated, Guanzhong faces insect-driven crises, and southern Shaanxi is flood-prone.