The in-depth analysis of the development process of the delta front is of great significance for the judgment of the sedimentary environment,and it is necessary to deeply explore the formation characteristics and mechanism of the delta front from the perspective of hydrodynamics. In this study,the vertical distribution of the flow velocity in river water bodies and the development characteristics of delta front sedimentary bodies are investigated,from multiple perspectives of hydrodynamics,flume experiments,and underwater geomorphological observations. The results show that the phenomenon of river flow velocity,exhibiting a monotonic decrease with depth,has not been given sufficient attention. The terrain undulation of the middle and lower reaches of the riverbed increases with the flow direction,resulting in the underwater sand waves perpendicular to the flow direction,while the terrain undulation of the river section perpendicular to the flow direction becomes more and more gentle. During the process of rivers entering the sea,there will be a mainstream channel without branching channels underwater. Additionally,the originally undulating riverbed will gradually be filled up,changing from a sharp V-shaped or W-shaped to a U-shaped. It can be concluded that most of the front edge of the delta are sheet-like or fan-shaped,rather than a strip of erosion surface along the flow direction. Microfacies such as underwater distributary channels and bays do not develop in the delta front subfacies,which cannot be found in the modern delta front subfacies and are not supported by flume experiments. Furthermore,a water depth velocity interaction model for river channel and delta sedimentation is proposed.

The upper Oligocene Huagang Formation is crucial for oil and gas exploration in the central and southern Xihu sag of the East China Sea Shelf Basin. However,there has been ongoing debate on the sedimentary system,and limited research has been conducted on the characteristics of sand body architecture and the controlling factors. This paper studied the sedimentary environment,microfacies types,sand body architecture,and controlling factors of the upper Oligocene Huagang Formation through a comprehensive analysis of core,logging,and seismic data. The upper Huagang Formation in the central-south part of Xihu sag shows shallow-water delta plain sedimentation,with distributary channels being the predominant type of sand body. These distributary channels are categorized into three types based on their curvature: braided(curvature=1~1.05),meandering(curvature>1.15),and braided-meander transition(curvature=1.05~1.15). The sand bodies found in braided distributary channels are wide and thick,with intertwined wide bands. Channel bars in these channels are arranged in a speckled pattern. The sand body’s vertical stacking style is mainly characterized as incised stacking. In contrast,the sand bodies in meandering channels are narrow and thin,appearing as either single strip type or bifurcation-merging type in the planar direction. Thick sand layers are distributed as point bars in the channel margin,and the vertical stacking style is mostly isolated. The braided-meandering type of diversion channel is a transitional type between braided and meandering channels. It is characterized by moderate-sized channel sand bodies containing inner channel bars and point bars. The thickness and width of these distributary channels are positively correlated in a logarithmic manner. The ratio of width to thickness follows the pattern of braided type>transitional type>meandering type. The architecture characteristics of distributary channels are primarily influenced by paleogeomorphology and changes in base levels. Paleogeomorphology controls changes in channel types within shallow water delta plain,and low curvature braided distributary channels are more likely to develop in steep terrain. As the long-term base level increases,the size of distributary channels decreases,while a rise in mid-term base level has resulted in the transition of distributary channel sand bodies from incised to superimposed and isolated stacking types. This research enhances our understanding of the sedimentary structure of shallow water deltas and provides valuable guidance for predicting and developing distributary channel reservoirs in underground shallow water deltas within oil and gas fields.

The‘Taishan earthquake’ named after Mount Taishan,occurred in 1831 BC,which was the earliest historical earthquake recorded by writing-materials in China. Bamboo Annals recorded that the strong earthquake occurred,when the emperor named “Fa” was climbing the Mount Taishan in the seventh year of Xia Di Fa(i.e.1831 BC). The earthquake shocked the emperor at that time,so for the first time,it was written and named after Mount Taishan. Apparently,the geographical position that the emperor “Fa” was threatened by the earthquake was at the hillside of the Mount Taishan. However,seismic geologists have been unable to find any seismic-geological records or traces of the historical earthquake in the Taishan area and its surroundings. Therefore,the epicenter and magnitude of the “Taishan earthquake” have been a mystery. By reobserving the discovered seismo-geological remains,combined with a series of tests,experiments and analysis,the paper provides evidences that the “Taishan earthquake” was a strong and historical earthquake with its epicenter located in the Anqiu area within the Tanlu fault zone. First of all,in the Holocene soft soil layers of limnetic facies in the Anqiu-Xiazhuang Basin of the Tanlu fault zone about 200 km away from Mount Taishan,there are macroscopical seismic traces such as seismic-subsidence synclines and co-seismic micro-faults,which recorded epicenter-intensity for degree of IX ,seismic magnitude for M7.0. Second,by means of the results of dating¹⁴C isotope,combining with calculating the sedimention time of the related soil layer,the earthquake time(i.e.1827 BC)obtained is very close to 1831 BC. Third,based on seismic intensity attenuation model in North China,the attenuation intensity induced by the earthquake is calculated to the degree of VI near Taishan. The Chinese earthquake intensity table shows that the VI intensity completely makes people stand unstable or escape outdoors,which accords with the historical records that the mountaineering emperor was frightened by the earthquake.

In recent years,oil and gas exploration in the Junggar Basin has gradually shifted from conventional traps outside the source to lithological traps within the source. The Upper Urho Formation is currently the main exploration target for boosting reserves and production in the basin. The distribution of sedimentary system has a controlling effect on the distribution of lithological reservoirs in the Upper Urho Formation. Using drilling cores,thin sections,combined with seismic data and drill cuttings and wireline logs,this study identified and characterized the sedimentary facies and depositional systems of the Upper Urho Formation in the Junggar Basin,and summarized the large-scale transgression. The sedimentary model of fan(braided river)delta-beach bar composite sandy conglomerate body was analyzed,and its controlling factors were analyzed. The results show that: (1)The study area is characterized by various sedimentary facies,including fan delta,braided river delta,and shallow lake beach bar. Among them,fan-delta plain and fan-delta front are mainly developed in the west of the basin,while braided river-delta plain and braided river delta front mainly developed in the east and north of the basin,and beach-bar is mainly superimposed on fan-delta and braided river-delta fronts or occurs independently at their front ends. (2)The depositional system of each member of the Upper Urho Formation developed under the background of overall lacustrine transgression. During the first member of Urho Formation,the basin was relatively small,and the deposited sand bodies were thick and of limited lateral extent,located in proximity to the depression center;during the second member of Upper Urho Formation,with continuous sediment supply and increased water depth the area of the lacustrine basin increased,with thinner but more extensive sand bodies deposited;during the third member of Upper Urho Formation,lacustrine transgression was enhanced,basin area was thus further expanded,and lacustrine mudstone was widely developed in the basinal area. (3)The fan(braided river)delta front-beach-bar composite gravel body was formed under continuous change of lake level and transformation of lake waves in the fan delta state and braided river delta front. (4)During the depositional period of the Upper Urho Formation in the Junggar Basin,the main controlling factors of the depositional system were climate,source supply,lake-level changes,and palaeotopographic slope and palaeogeomorphology at the time of deposition. This study provides a geological basis for oil and gas exploration in the Upper Urho Formation.

Uplift processes of the southern margin of the North China Block are of great significance for understanding interactions between the Qinling Orogenic Belt and the North China Basin. Based on sedimentary facies analysis,this paper studies the detrital zircon U-Pb geochronology and fission track chronology of the Permian Shihezi Formation in Luonan area,and discusses the source characteristics and uplift processes of the southern margin of the North China Block. It is expected to provide a sedimentary constraint for the subduction time of the Mianlue Ocean Basin and provide a possible source area for the Triassic recycled sediments in the southern North China Basin. The results show that the Permian Shihezi Formation in Luonan area experienced an upward change in sedimentary facies from alluvial fan to braided river,and then to delta. The sample from the lower part of the strata contains three groups of U-Pb ages,i.e.,353-280 Ma,1139-400 Ma,and 2620-1306 Ma. The fission track ages are decomposed into three peaks of 199 Ma,255 Ma,and 408 Ma. The sample from the upper part of the strata contains two U-Pb age groups,i.e.,339-259 Ma and 2655-1700 Ma,and the fission track ages were decomposed into three peaks of 205 Ma,268 Ma and 656 Ma. The results show that the southern margin of the North China Block received sediment from the Qinling Orogenic Belt during the early sedimentary period of the Shihezi Formation,but the sediments mainly came from the northern margin of the North China Block in the late depositional stage. The tectonic pattern had been transformed from high in the south to high in the north in this time. The initial uplift of the southern margin of the North China Block occurred during the Middle-Late Permian,which was related to the initial subduction of the Mianlue Ocean Basin,and became a potential provenance area to the Triassic strata in the south of the North China Basin.

The study of incidence and attributes of regional extreme climatic events under the background of global change is a frontier of climate change research. This paper reconstructs the extreme flooding events with a probability of 10% in the Northeast China in 1750-2020 using historical documentary records and precipitation data,and then analyzes its incidence characteristics and driving mechanism. The main conclusions include: (1)In 1750-2020,29 extreme flooding events were identified in the Northeast China,exhibiting fluctuating patterns,with 1871 to 1930 marking the period of highest frequency over the past 270 years;(2)The global and regional warming significantly enhanced the frequency of extreme flooding events in the Northeast China;(3)The anomaly of the monsoon rain belt caused by the change of the East Asian summer monsoon is the direct cause of the occurrence of extreme flooding events in the Northeast China. Particularly,periods with a stronger monsoon and a northward shift in the rain belt significantly raise the likelihood of such events;(4)The Indo-Pacific warm pool and the sea surface temperature anomalies in the tropical central and eastern Pacific caused the incidence of extreme floods events in northeast China by affecting the location of the East Asian summer monsoon and the water vapor transport. The positive anomaly of water vapor transport at the time of La Niña years is crucial for the occurrence of extreme flooding,and is a reliable predictor of extreme flooding events in the Northeast China.

The sand bodies of the Member 2 of the Upper Triassic Xujiahe Formation in the Xinchang structural belt of western Sichuan Basin are widely distributed,with various types of sand bodies and large thickness differences. This results in uneven distribution of interlayer barrier bed and intraformational bed in gas reservoirs,and strong reservoir heterogeneity. Therefore,it is crucial to investigate the sedimentary microfacies,distribution characteristics and architecture of reservoir sand bodies,so as to lay a foundation for the following reservoir prediction and efficient gas reservoir development. Using core,well logs,3D seismic and laboratory data,and guided by the theory of high-resolution sequence stratigraphy proposed by T.A. Cross,the authors systematically examined the structural characteristics and controlling factors of sand bodies in the second member of Xujiahe Formation in the Xinchang structural belt,western Sichuan Basin. The results show that: The study area was largely located in a shallow water delta front environment,which consists mainly of subaqueous distributary channel sand bodies with subordinate mouth bar sand bodies. These channel sand bodies are characterized by frequent lateral migration,multiple vertical amalgamation and extensive areal coverage. It is concluded that in the study area there are two main categories and nine subcategories of sand body vertical stacking patterns and three lateral contact patterns. The structural characteristics and development patterns of sand bodies are controlled mainly by base-level fluctuation and river energy. Finally,the sedimentary facies and sand body development model of the Xinchang structural belt in western Sichuan Basin are established,which has important applications for guiding exploration and development of gas reservoirs in similar settings.

It is of great significance for understanding the initiation and evolution of sandstone-type uranium deposits from the perspective of tectono-sedimentary evolution. In this study,based on a literature review,fieldwork,logging and seismic data,the tectono-sedimentary evolution of the Shizigou and Qigequan Formations in Qigequan Anticline in the Qaidam Basin and its links to the mineralization of sandstone-type uranium deposits are revealed. Our findings indicate that: (1)The Shizigou Formation is characterized by argillaceous-sandstone-rich stratum associated with retrogradation,while the Qigequan Formation is characterized by conglomerate-rich stratum associated with progradation. The Neogene-Quaternary angular unconformity developed between the Shizigou and Qigequan Formations and the Intra-Quaternary angular unconformity developed inside the Qigequan Formation. Large-scale alluvial fans,composed of debris flow,incised-valley-fill,and sheet flow deposits,were developed in the Shizigou and Qigequan Formations,and the sandy earthquake-induced soft-sediment deformation layers were frequently developed in the Shizigou and Qigequan Formations. (2)The most intensive uplift and denudation events occurred between the Neogene and the Quaternary,resulting in the initiation of the Neogene-Quaternary angular unconformity and the tectonic setting of the Qigequan Anticline. (3)It can be inferred that these potential uranium mineralization columns of the Shizigou Formation in the Qigequan Anticline developed in the uplift and denudation events between the Neogene and the Quaternary. The uplift and denudation events led to the initiation and evolution of the uranium-bearing structure,and increased the uranium flux from the source area and dominated the spatial distribution of the potential uranium mineralization columns ultimately. The Neogene-Quaternary angular unconformity can be used for the spatial distribution predicting of the potential uranium mineralization columns as a key tectonic identification mark. In addition,the thin interbeds of sandstone(including the conglomerate)and mudstone in the middle and distal parts of alluvial fans,with sand(including the conglomerate)percentage ranging from 20% to 50%,can be used for the spatial distribution predicting of the potential uranium mineralization columns as a key sedimentary identification mark. This research provides sedimentary and stratigraphic evidence for the basin analysis of the northeastern Tibetan Plateau and is of great reference value for the exploration of sandstone-type uranium deposits in other anticlines in the Qaidam Basin.

A shallow water delta was developed in the Lower Jurassic period in the Dongdaohaizi sag,Junggar Basin,but its sedimentary evolution and main controlling factors were not fully understood. Through the analysis of well logging,core and geochemical data from the Dongdaohaizi sag and its surrounding areas,the sedimentary facies,paleogeomorphology and paleoclimate of this region were analyzed. The study identified three subfacies within the shallow water delta: delta plain,inner front,and outer front. The delta plain subfacies consisted mainly of distributary channels,forming glutenite layers over a hundred meters thick. The inner front featured medium-fine sandstone with argillaceous interlayers,while the outer front was mainly composed of sheet sandstone microfacies interbedded with mudstone and argillaceous siltstone. The paleogeomorphology of the area was higher in the east and lower in the west,categorized into paleo-highland,paleo-slope and paleo-depression based on relative positions and slopes. Analysis of geochemical indicators and sedimentary characteristics suggested fluctuations between humid and arid conditions during the Early Jurassic,with the lake level experiencing three progression-regression cycles. The progradation and regradation of the delta extended over tens of kilometers with the sedimentary distribution and evolution influenced by both paleogeomorphology and paleoclimate. The gentle overall paleogeomorphology provided a foundation for shallow water delta development,while regional paleogeomorphology height and evolution affected sedimentary system distribution and transition. Alternating dry and wet paleoclimate conditions affected lake level fluctuations,thereby controlling delta progradation and regradation. Through a comprehensive analysis,the progradational and regradational depositional models were established for shallow water delta sedimentary patterns,offering valuable insights into the impact of paleogeomorphology and paleoclimate on shallow water delta,and serving as a reference for future exploration in the area.

To assess the potential for natural gas exploration in the Quaternary Qigequan Formation in the Sanhu area of the eastern Qaidam Basin and identify favorable lithologic gas reservoir exploration zones and targets,this paper systematically analyzes the provenance composition of the Qigequan Formation in the area. By examining parameters such as heavy mineral assemblage,ZTR index,stability coefficient of heavy mineral sand sandstone clastic composition,the study determines the provenance direction and reconstructs the parent rock type. The findings reveal that the stability coefficient and ZTR index of heavy minerals in the Sanhu area increased from the margin to the center of the Qaidam Basin during the sedimentary period of the Qigequan Formation,which was roughly distributed in a ring belt. The study identifies different main heavy mineral assemblages in various source areas and significant variations in the content of unstable heavy minerals. The study indicates that the Golmud provenance flows in a north-west direction,influencing the southern part of the Sebei area,while the Wutumeiren provenance has a smaller scale and flows northeast,impacting the southwestern part of the Tainan area and the Senan 3 well area. Additionally,the study shows that the provenance scale of Mt. Xitieshan-Emnik and Mt. Lvliang is limited,with distinct effects on surrounding regions. The Tainan-Sebei area is primarily influenced by the Wutumeiren provenance and Golmud provenance. This study establishes that the Sanhu area in the Qaidam Basin is characterized by the Wutumeiren provenance and Golmud provenances. The Kunlun Mountain gentle slope provenance system,the Qilian Mountain steep slope provenance system made up of the Xitieshan-Emnike Mountain source and the Lvliang Mountain source,and the blended source system in the Tainan-Sebei area within the basin can offer direction for natural gas exploration and development in this region.

Despite significant breakthroughs in oil and gas exploration in the glutenite section of the Qingshuihe Formation in the southern Junggar Basin,the sedimentary characteristics,genetic mechanism and controlling factors of the glutenite remain unclear,which has become a key restricting factor for hydrocarbon exploration. As such,we investigated the lower Qingshuihe Formation glutenite body in the western section of the southern Junggar Basin based on wireline logs,cores,outcrops and experimental data,with a focus on the lithofacies,lithofacies assemblage and distribution of the glutenite body,as well as their main controlling factors and genetic mechanism. Six types of lithofacies and lithofacies assemblages and genetically different glutenites are identified in the lowstand and transgression systems tracts of the Qingshuihe Formation in the western section of the southern Junggar Basin. The lowstand and transgression systems tracts of the Qingshuihe Formation in the southern Gaoquan area of the western section are dominated by alluvial fan and fan delta depositional systems,and braided river delta depositional system predominates the northern Caindic area. During the depositional period of the Qingshuihe Formation,glutenite sedimentation in the south western section of the Junggar Basin was affected by the nature of the parent rock in the provenance area,sediment supply and paleoclimate. Among them,nature of the parent rock in the provenance area and sediment supply control the sedimentary type and scale of the glutenite body. While paleoclimate affects the weathering and denudation degrees of the parent rock area and the sedimentary transport environment. Based on the controlling factors and sedimentary characteristics,a sedimentary model for the southern alluvial fan-fan delta and the northern braided river delta front of the Qingshuihe Formation lowstand and transgression systems tract in the western section of the southern Junggar Basin has been established,which can provide a geological basis to aid discrimination between different glutenite bodies and hydrocarbon exploration in similar settings.

The Jurassic Qigu Formation in the Yongjin area is a set of important oil-bearing strata in the central Junggar Basin. It is a typical deep-buried sandstone reservoir with a burial depth of 5400~6100 m,and its reservoir quality controls oil and gas reserves and production. In this paper,the diagenetic evolution process of deep-buried sandstone reservoirs in the Qigu Formation is studied by using the data of cast thin section,cathodoluminescence,scanning electron microscopy,XRD whole rock and clay mineral analysis. A diagenetic sequence is established,and the impacts of various diagenetic processes on reservoir quality are quantitatively assessed,integrating regional burial and hydrocarbon charge histories to delineate the reservoir’s diagenetic evolution. The lithology of the Qigu Formation reservoir in the Yongjin area is mainly composed of feldspathic lithic sandstone and lithic sandstone. The cement includes mainly carbonate minerals,siliceous minerals and clay minerals with low composition maturity and high texture maturity. The reservoir space types are mainly the remaining primary intergranular pores and secondary intergranular dissolved pores. Overall,the reservoir porosity changes are mainly controlled by compaction,cementation and dissolution,which are the main diagenetic factors reducing reservoir porosity,resulting in primary pore loss rates of 65.98% and 21.80% respectively. Dissolution increases the porosity by 5.13%,which effectively improves the physical properties of the reservoir. The comprehensive study shows that the diagenetic evolution of the Qigu Formation reservoir in the Yongjin area is mainly controlled by four factors: sedimentary environment,diagenesis,burial history and oil and gas charging. Diagenesis plays a role in the transformation of reservoir physical properties and is the critical determinant of the observed reservoir heterogeneity.

During deposition of the Middle Ordovician Majiagou Formation,a series of paleo-uplift was discovered around the Ordos restricted sea. It remains relatively poorly studied as to how Lüliang paleo-uplift controlled deposition of the Majiagou Formation,which restricted understanding of sedimentary environments of the Majiagou Formation in the northeastern part of the basin. Through detailed measurement and sampling analysis of the Fugu outcrop in Shaanxi Province,combined with the drilling and core data,stratigraphic thickness,lithofacies and microfacies of the Majiagou Formation were studied. Lastly,controls of the Lüliang paleo-uplift on deposition of the Majiagou Formation are discussed. The research results show that: (1)the Lüliang paleo-uplift intermittently blocked the seawater circulation between the Ordos restricted sea and the North China sea. (2)The paleo-uplift was located underwater during the high sea level period,and the barrier to seawater circulation was weak;the stratal thickness in the west of the paleo-uplift has little variation;the underwater paleo-uplift formed a limestone flat,and limestone flat and limestone/dolomite flat formed in the west of the Lüliang paleo-uplift. (3)During the low sea-level period,the paleo-uplift was intermittently subaerially exposed,and obviously blocked circulation of seawater between the Ordos restricted sea and North China sea;the stratal thickness decreases in the east of the paleo-uplift,and sedimentary facies changes from muddy dolomite in the paleo-uplift to limestone in the east of the paleo-uplift. The stratal thickness increases significantly to the west of the paleo-uplift,forming argillaceous dolomite flat,gypsum dolomite flat,and gypsum and saline lacustrine facies. The study provides petrological and paleo-environmental evidence for the Majiagou Formation in the eastern part of the basin.

The ruins of the Qiaotou village bridge and the strip stone pavement in front of the bridge in Dongzhai port,Northern Hainan Province,are now submerged under the water surface at low tide and covered with mud,with only a small portion exposed. According to genealogical records,tombstone inscriptions,and field investigations,the bridge was still operational 45 years after the Qiongzhou earthquake,specifically in 1650 AD. It indicates that the bridge sank into the sea nearly a century after the 1605 Qiongzhou earthquake. The research shows that since 1650,the ground in Qiaotou village area of Dongzhai port has been subsiding at a rate of no less than 1.5 cm per year according to recent survey in 1984. The survey also shows that in the past 30~40 years,the ground of central and north section of Dongzhai port have slowly subsided at a rate of not less than 1 cm/a. The sinking rate was likely higher in the early period following the Qiongzhou earthquake. This paper roughly estimates that the amplitude of coseismic subsidence of this earthquake may reach about 2~3 m. The paper discusses the mechanisms behind slow subsidence after the earthquake,attributing it to persistent intense activity beneath the crust due to mantle plume uplifts,crustal stretching,and fracturing,accompanied by multiple volcanic activities or eruptions over various geological periods since the Cenozoic. Prior to the earthquake,the crust of northeastern Hainan,had been uplifting for thousands of years,accumulating significant energy and forming sub-crustal hotspots. The reduction in friction on the fault surfaces due to groundwater penetration into the tension fractures initiated the land subsidence,culminating in a significant earthquake that caused extensive land to sink into the sea. After earthquake,the residual energy continuous to stretch the fault,resulting in continuous graben type settlement of crust in Dongzhai port. The rapid and continuous penetration of seawater into the fault during and after the earthquake reduced the friction force on the fracture surface,stabilizing the post-seismic fault movement. These factors are considered the primary reasons for the prolonged,significant subsidence of Dongzhai port for centuries following the earthquake. Connecting to the historical context,Dongzhai port has undergone transformations from land to sea and back,a process that has continued from the Late Pleistocene and possibly up to the Early Holocene.

It is of great significance to study the mechanism of hydrothermal activity,related to the Yanshanian thermal events in Majiagou Formation,Fuxian area of the Ordos Basin,to reveal the origin of reservoirs. The two stages of hydrothermal activity related to the Yanshanian thermal events in Majiagou Formation,Fuxian area are identified,based on a comprehensive analysis of petrology and geochemistry,including core and thin section observation and cathode luminescence,homogenization temperature of fluid inclusions,carbon and oxygen stable isotopes,strontium isotope,electron probe microanalysis and rare earth element analyses. The results show that the stage-Ⅰhydrothermal activity is characterized by the development of saddle dolomite in the fissure-cavern systems,with low and negative δ¹³C and δ¹⁸O values,higher strontium isotope value than normal marine limestone,negative abnormal Eu and La in rare earth elements,rich content of MnO,FeO,SrO and poor content of K₂O and Na₂O in trace elements,and high homogenization temperature of fluid inclusions. The geochemical characteristics reveal that the saddle dolomite was formed by the combined action of internal fluids in the Ordovician strata,shallow fluids in the Carboniferous-Permian strata,and deep hydrothermal fluid under Early Cretaceous extensional fault activity,in which the deep hydrothermal fluid is post-magmatic hydrothermal fluid related to basalt eruption. The stage-Ⅱhydrothermal activity is characterized by quartz precipitation in fracture-vug systems,and the development of fractures calcite that cut saddle dolomite,with δ¹³C values close to the background value of Ordovician carbonate rocks,low δ¹⁸O value,higher strontium isotope value than saddle dolomite,negative abnormal La and positive abnormal Eu in rare earth elements,rich content of MnO,FeO,K₂O,Na₂O in trace elements,and high homogenization temperature of fluid inclusions in quartz. The geochemical characteristics reveal that the calcite and quartz were formed by the combined action of internal fluids in the Ordovician strata and deep hydrothermal fluid under Early Cretaceous extensional fault activity,in which the deep hydrothermal fluid is the post-magmatic hydrothermal fluid related to the activities of the Early Cretaceous monzonite and monzonitic diorite magmatic intrusion. Hydrothermal activity related to Yanshanian thermal events has both constructive and destructive effects on the formation and preservation of reservoir space in the Majiagou Formation,but the overall sphere of influence is limited.

Paleocave play a crucial role in the storage and transport of karst groundwater in the covered area,and the exploration and identification of their morphological and internal structural characteristics are of certain guidance for understanding the formation process of karst in covered coal fields and the prevention and control of karst water inrush damage in mines. In recent years,through a detailed geological investigation of the Ordovician karst outcrops in the Shungeng mountain in Huainan,Anhui Province,on the southern edge of the North China Plate,a typical paleokarst cave was found at the Ordovician formations. This study analyzes the morphological features and internal structures of the paleocave using field observations,microstructural identification,paleohydrology,and paleotectonics. The cave developed along the sedimentary interfaces between the Majiagou and Xiaoxian formations,exhibiting varying widths—wider on the west side and narrower on the east. The maximum vertical height between layers reached 9.8 meters,and the cave extended over a length of 125 meters. Evidence of paleowater erosion and corrosion is preserved on the cave ceiling,and gravity-induced collapses have resulted in various fill types,including debris collapse fill,chemical fill,and mixed fill,primarily consisting of limestone and dolomite,with minerals such as calcite,dolomite,and cryptocrystalline silica. Combined with the regional geological and tectonic evolution,paleocave formation experienced four stages: the fissure development,interlayer karst formation,,interlayer cave growth,and collapse filling and compaction,which are mainly controlled by layer fissure,erosive fluid and vertical karst zoning. The results can provide useful reference for prevention and treatment of deap karst water inrush in Huainan and other North China coalfields.

层序地层学作为一种新的盆地分析方法，受到广大地质学家的重视，尤其是陆相层序构型与数值模拟研究已成为一个国际性热门方向。文中总结了陆相层序构型在国内外的研究进展，介绍了国外近年来的“下游控制区”和“上游控制区”概念以及层序构型特征，“下游控制区”发育依赖于相对海(湖)平面变化的“低位正常海(湖)退”、“海(湖)侵”、“高位正常海(湖)退”和“下降阶段”体系域，“上游控制区”发育不依赖相对海(湖)平面变化的高河道合并体系域和低河道合并体系域。国内层序构型研究也有多种观点，最有代表性的应该是“L型、T型、TH型、H型(E-H型和L-H型)”层序构型的划分。陆相层序模拟已经从水槽物理实验为主发展到当今以数值模拟及水槽实验并举的时代。在介绍层序数值模拟发展史、国内外研究现状的基础上，重点介绍了SEDPAK正演化模拟、SEDSIM正演数值模拟、基于Delft3D模型的三维正演模拟、DIONISOS的三维正演模拟及基于N-S方程的层序数值模拟等5种数值模拟方法，总结了陆相湖盆层序构型及数值模拟在油气勘探开发领域的应用情况，分析了目前存在的理论问题、数值模拟技术难点及数值模拟未来的发展方向。

中国大陆地壳在奥陶纪时由华北、扬子、塔里木三大陆块及围绕它们的诸多微陆块和造山带组成。基于陆块、微陆块和造山带等不同属性地体的识别特征，按陆块、洋板块中的微陆块、造山带和疑问块体4种类型，分别阐述它们在中国奥陶纪的发育特征。在此基础上，综合古地理信息，提出中国奥陶纪共划分出4个大区16个地理区的新认识。该时期中国各陆块主要在环西伯利亚、古亚洲洋、原特提斯洋和冈瓦纳北缘分布，由此归纳为4个大区，其中华北和塔里木分割了古亚洲洋和原特提斯洋，但归入原特提斯洋大区中。环西伯利亚大区可分为北疆区和兴安区，前者由阿尔泰、准噶尔—吐哈微陆块和东西准噶尔造山带组成，后者囊括额尔古纳、兴安、锡林浩特、松辽和佳木斯等东北微陆块群。古亚洲洋大区仅分出中天山—北山区，伊宁微陆块为该区成员。原特提斯洋大区除了华北区和塔里木区外，还包括柴达木—祁连、昆仑—秦岭、扬子、华夏、印支和松潘—甘孜区，其中中阿尔金和全吉微陆块属于柴达木—祁连区，义敦微陆块属松潘—甘孜区。冈瓦纳大区分为羌塘、拉萨、喜马拉雅、滇缅泰马和海南区，其中保山微陆块和临沧微陆块为滇缅泰马区的组成部分。此外，阿拉善和敦煌块体分别归入华北和塔里木区中。上述中国奥陶纪地理分区的认识与前人存在较大差异，作者旨在抛砖引玉，希望能引起更多学者关注并探求更合理的划分方案。

海相白云石胶结物在前寒武纪广泛发育，因其多样的形态、复杂的成因及其对前寒武纪海水性质的指示意义，近年来引起了广泛关注。目前对前寒武系海相白云石胶结物的研究主要集中在两个方面，一是基于矿物学特征分析进行成因探讨，二是探索其反映的前寒武纪海水性质。前人对海相白云石胶结物成因的认识包括原生沉淀与次生交代2种观点，但因缺乏可靠的地球化学证据支撑而存在争议，主要体现在对原生沉淀成因白云石胶结物的具体沉淀机理及其相应的海水化学条件仍不清楚，对次生交代成因白云石胶结物的前驱矿物类型也存在较大分歧。为进一步推动海相白云石胶结物的研究，文中首先系统总结了前寒武系海相白云石胶结物的时空分布特征、岩石学、矿物学及地球化学特征，并从原生沉淀、次生交代、生长组合形态3个方面全面回顾和评述了关于海相白云石胶结物成因研究的现状。在此基础上，对未来相关研究提出以下几点展望：(1)基于矿物成核与生长原理，结合微区或原位地球化学分析，开展不同类型海相白云石胶结物成因研究；(2)评估微生物在海相白云石胶结物形成过程中的具体作用；(3)以前寒武系白云石胶结物为载体探索前寒武纪古海洋海水性质的演化，需建立在厘清其成因的基础之上。

随着气候模式在古气候研究中的应用越发广泛，更加准确的古地理边界条件重建成为研究深时气候变化机制的关键，而古地理边界条件重建过程中的不确定性却少有人关注。本研究基于古海陆分布、古海深、古地形重建方法及资料选择，研究古地理边界条件重建过程中的不确定性以及其对气候模式模拟结果的影响。结果显示，重建过程中板块运动模型的选择、海陆分布的修正、海洋洋壳年龄数据的更新、大洋深度—洋壳年龄关系模型选择、沉积物模型选择以及古地形高度代用指标的选择都会导致不同的古地理边界条件重建结果。更重要的是，这种古地理边界条件的差异会进一步影响模式模拟结果中的温度、盐度以及洋流等重要的气候环境变量。这表明重建气候模式中古地理边界条件时需根据具体需求合理选择重建资料，同时也需基于密集和可靠的代用指标进一步优化重建资料，从而减少古地理边界条件对古气候模式结果可靠性的影响。

沉积构造不仅能揭示海相细粒陆源碎屑岩的形成环境和沉积时的古水动力条件，还影响到页岩气储集层的渗透性及可压裂性。文中通过系统总结国内外相关研究成果，明确了海相细粒陆源碎屑岩沉积构造的主要类型及成因。海相细粒陆源碎屑岩主要发育物理成因、化学成因和生物成因3类沉积构造：物理成因构造主要有流动成因构造和软沉积物变形构造，前者包括交错纹理、水平层理(纹理)、块状构造、递变纹理和复合纹理，后者包括滑塌—滑移构造、负载构造、火焰状构造、球—枕构造、包卷层理、扭曲纹理、碎裂纹理和坠石；化学成因构造包括碳酸盐结核和黄铁矿结核；生物成因构造主要有生物遗迹构造和生物扰动构造。该3类沉积构造主要为细粒浊流沉积、等深流沉积和远洋—半远洋沉积成因，少数为沉积物变形成因。沉积构造类型直接影响页岩气储集层的渗透性、水力裂缝的生成及延展方向。

四川盆地北缘震旦系灯影组发育软沉积变形构造，其成因机制尚不明确。结合野外露头对川北广元地区灯影组软沉积变形构造发育特征、分布及成因进行系统分析。研究表明，广元地区震旦系灯影组三段软沉积变形构造主要分布于中下部灰白色薄层灰岩及灰绿色—紫红色薄层泥岩中，可见液化脉、液化卷曲变形、液化角砾岩及层内断层4种典型构造。灯三段早期浅水、较安静水体沉积物受同期循环剪切应力及地层应力复合作用，为持续性古地震诱发的液化变形所致。垂向上可识别出2期不完整振动液化序列，表明灯三段至少存在2次持续的古地震活动。综合分析指示上扬子克拉通北部灯三段沉积期构造活动强烈，地震活动应与桐湾运动Ⅰ幕晚期裂陷槽的拉张活动相关。

探究遗址沉积过程与古环境背景对于全面了解古人类生存行为信息具有重要意义。江西上湖遗址是中国南方地区新近发掘的一处旧石器时代旷野遗址，遗址均质红土B层中出土了丰富的石制品，表现出小型化特点，年代始于距今约2.6万年前。本研究对上湖旧石器遗址沉积地层开展了野外考察和室内土壤微形态、磁化率、粒度和地球化学元素分析，同时对出土的石制品进行了考古埋藏学分析。地学和考古学方法二者相互印证，明确揭示出该遗址区均质红土B层仅受到了低能坡面流水作用，保存了较为完整的古人类技术行为信息。推测古人类在MIS2阶段频繁占据和使用上湖遗址等区域，可能与拥有小型石片石器技术的华北地区人群难以忍受该时段北方极端寒冷干燥的气候条件被迫向南迁徙、从而到达了气候相对干凉的长江中下游地区进行生产活动有关。并且上湖遗址古人类采取了偏后勤式流动策略，以应对异常极端气候带来的资源分布不均和可预测性降低等风险。

顺应国家深海、深地、深空和深蓝战略部署，陆地钻井不断向深层超深层进军，但深部极端环境测井资料获取困难，采集新技术(核磁共振、成像测井和阵列声波)测井少，导致测井资料多解性强，亟需利用有限的地球物理测井信息挖掘深层超深层钻井蕴含的地质信息。经过大量的文献调研，论述了深层超深层测井评价的重点，通过对典型研究案例的分析，系统地梳理测井地质学在深层超深层领域的应用，包括利用测井资料实现对井旁构造地质现象解读、沉积学信息拾取、储集层评价与预测、储集层裂缝评价和对地应力评价。最后探讨了深层超深层领域发展趋势：重视多角度数据的融合(岩心、实验资料和地震资料等数据),并根据深层超深层环境的差异，发展适应深层超深层环境因素的先进岩石物理模型。同时在大数据、人工智能的发展背景下，利用新技术测井的优势，推进深层超深层领域测井地质学突破技术瓶颈。

塔里木盆地顺北地区中下奥陶统鹰山组白云岩是极具勘探潜力的岩相类型，但目前对该地区成层分布的白云岩成因及其物性差异尚无系统阐释。本研究基于详细的岩石学观察、碳氧同位素和微区微量稀土元素分析、碳酸盐岩U-Pb定年、覆压孔渗测试等资料，对鹰山组内幕成层发育的白云岩类型、成因机制进行探讨，并初步评价了不同成因白云岩的物性差异。研究发现：（1）顺北地区鹰山组下段白云岩相对发育，主要包括2类成层分布白云岩，分别是埋藏压溶白云岩（Ⅰ类）和准同生渗透—回流白云岩（Ⅱ类）;（2）I类白云岩为埋藏白云石化成因，分布于低能沉积相内，为埋藏过程中缝合线建造驱动黏土矿物转化成因机制，在顺北中部地区较为发育；（3）Ⅱ类白云岩为准同生渗透—回流白云石化成因，主要分布于地貌较高、相对高能的沉积相区，在顺北西区、顺南地区相对发育；（4）Ⅰ类白云岩实测物性数据(φ:0.3%～1.0%;K:0.003×10^-3～0.074×10^-3μm²)低于Ⅱ类白云岩(φ:0.4%～2.0%;K:0.009×10^-3～0.055×10^-3μm²),但Ⅰ类白云岩的发育可提升地层中白云岩和灰岩互层的比例，具裂缝改造成储潜力。研究成果对于塔里木盆地顺北地区超深层白云岩油气勘探选区具有借鉴意义。

桂中坳陷柳城北区块下石炭统鹿寨组页岩气取得突破，有望成为四川盆地以外海相页岩气的接替领域。但受地层非均质性及纵横向相变频繁的制约，开展页岩类型识别和储集层评价存在困难。文中建立了基于“矿物组分+TOC含量”的页岩类型划分方案，利用元素—矿物转换最优化方程和BP神经网络模型分别实现页岩成分和TOC含量的测井识别与预测，并采用成像测井动态切片和纽扣电极视电导率图像2种方法识别表征页岩纹层。通过精细刻画不同页岩类型的纹层发育程度和含气性特征，阐明了研究区有利页岩类型及分布特征。研究表明：鹿寨组一段发育5种典型页岩类型。受沉积古环境控制，页岩分布呈现出较强的纵向非均质性。鹿寨组一段整体处于下斜坡相沉积环境，纵向上(1)至(7)小层沉积水体逐渐变浅，灰质含量减少而陆源碎屑供给增多，总有机碳含量也逐渐降低，页岩类型由富有机质硅质混合页岩、富有机质黏土质混合页岩逐渐相变为含有机质硅质混合页岩。其中(3)小层中富有机质硅质混合页岩与富有机质黏土质混合页岩的页岩组合类型有机质丰度高，纹层组合类型及发育程度较优，整体含气量和脆性均较高，为研究区的有利页岩类型。

为了深化对湖相细粒沉积岩储集层的认识，以渤海湾盆地济阳坳陷沾化凹陷渤南洼陷沙三下亚段（Es3L）为研究对象，利用岩心描述、薄片鉴定、扫描电镜观察、物性分析和测井曲线，揭示了储集层特征、分布规律及其主控因素。基于矿物组成、沉积构造和有机质含量，将渤南洼陷Es3L细粒沉积岩划分为6类岩相：富有机质纹层状灰质细粒混积岩（LF1）、富有机质纹层状长英质细粒碳酸盐岩（LF2）、富有机质层状灰质细粒混积岩（LF3）、富有机质层状/块状长英质细粒碳酸盐岩（LF4）、富有机质层状含长英细粒碳酸盐岩（LF5）、含有机质块状含长英细粒碳酸盐岩（LF6）。储集层的主要储集空间为粒间孔、晶间孔、溶蚀孔和层间微裂缝，储集层孔隙度主要介于0.67%～5.56%之间（平均值为4.93%）,渗透率主要介于（0.02～4.87）×10^-3μm²之间(平均值为0.59×10^-3μm²)。渤南洼陷Es3L细粒沉积岩储集层分布的主控因素包括岩相、沉积环境、成岩作用和有机质热演化。渤南洼陷Es3L的中下部的陆源输入水平低、水体盐度大、水体分层性强，主要发育岩相LF2和LF4,容易发育Ⅰ类和Ⅱ类优质储集层。渤南洼陷Es3L细粒沉积岩储集层处于中成岩A阶段，黏土矿物转化作用、溶蚀作用、重结晶和白云石化以及有机质热演化产生次生孔缝，改善了储集层物性。

中国北方烧变岩广泛发育，常见侏罗系煤层于中生代、新生代自燃形成的烧变岩。在烧变岩露头区，白色砂岩常与红色烘烤岩伴生，但国内外对其关注不够，成因不明。本次研究对伊犁、准噶尔、吐哈、鄂尔多斯等盆地周缘烧变岩区野外露头进行了观察，采集白色砂岩样品进行薄片鉴定、扫描电镜及能谱等测试与分析，对白色砂岩岩石学、矿物学特征进行观察和描述，认为中国北方侏罗系白色砂岩常分布在烧变岩的上覆、下伏或侧边位置，颜色多以灰白为主，结构疏松，孔隙发育，碎屑颗粒以石英、长石矿物为主，填隙物主要为高岭石，发育特殊的流体流动所致的孔洞构造；据其与烧变岩的空间相关性，推测白色砂岩的形成与煤层自燃有密切联系，煤层自燃导致高岭石大量生成、有色金属矿物或金属离子含量变化，这是砂岩呈现白色的主要诱因，因此烧变岩区所见白色砂岩为特殊类型的低温烘烤岩，其形成模式有3种：河谷下切型、裂隙下切型和山丘下渗型。

塔里木盆地塔河油田西北部中下奥陶统发育深切的地表水系结构，对水系两侧岩溶缝洞的发育影响显著，因此，对水系结构的定量描述及其演化模式的研究至关重要。基于三维地震资料，通过地震属性提取技术，对古岩溶台面和古岩溶地表水系进行了识别。同时，对水系的平面和垂向形态学结构参数进行了量化表征，据此探讨了古岩溶地表水系的形成与演化模式，剖析了水系演化与古岩溶缝洞发育的关系。研究结果表明：(1)塔河油田西北部自东向西发育3个岩溶台面和一个深切曲峡型地表流域结构。该流域的主干水系南北向汇流、分支水系东西向汇流，呈不对称分布。(2)水系单河曲弯曲率均大于1.5,超过了定义蛇曲的弯曲率临界值，具有典型的蛇曲特征。东西向河曲带弯曲率为2.42,南北向河曲带弯曲率为1.78。(3)东西向水系形态以单一“V”字形为主，南北向水系具有复合“V”字形，水系下切深度可达100～200 m。自东向西3个岩溶台面中水系的下切深度逐渐加大，水系宽深比平均值分别为4.06、3.52、3.03。(4)研究区古岩溶地表水系经历了自由曲流和深切曲流2个阶段，分别反映了水系的侧向侵蚀和垂向侵蚀作用过程。其中，水系的垂向侵蚀是逐步发生的，与3个岩溶台面的逐级抬升相适应。(5)深切曲流是区域性的最低排泄基准面，控制了河流两侧大型岩溶暗河的发育。每个岩溶台面具备独立的水循环结构，岩溶台面的逐级抬升促进了水系的差异演化，进而控制了岩溶暗河的规模和类型的差异性。对研究区古水系结构及其演化的认识对于古岩溶缝洞储集空间发育特征与分布规律的研究提供了重要的参考依据。

作为四川盆地超深层油气资源的主力产层之一，灯影组超深层碳酸盐岩储集层发育特征及其控制因素亟待进一步厘清。选取四川盆地内最新勘探突破的蓬莱地区灯影组灯四段超深层白云岩为主要研究对象，在野外露头、钻井岩心、显微薄片、阴极发光、扫描电镜及物性测试数据等资料的基础上，开展了储集层特征及主控因素等方面的研究。结果表明：（1）蓬莱地区灯四段储集岩主要包括凝块石白云岩、叠层石白云岩、泡沫绵层白云岩和砂屑白云岩；储集空间主要包括砂屑白云岩的晶间孔、晶间溶孔和溶洞，凝块石白云岩、叠层石白云岩和泡沫绵层白云岩的原生格架孔洞和后期溶蚀作用形成的溶蚀孔缝等。（2）凝块石白云岩和叠层石白云岩多发育孔洞缝型和孔洞型储集层，均具有较好的物性，孔隙度能达到4%以上，但前者平均渗透率可达2.43×10^-3μm²,后者仅为0.35×10^-3μm²。（3）综合分析成岩演化史，认为灯四段储集层先后经历了沉积—准同生阶段、表生阶段、浅—中埋藏阶段和深层—超深层埋藏阶段的成岩改造。（4）蓬莱地区灯四段储集层发育具有自台地内部向台地边缘逐渐减弱的分布规律，总体上显示“相—断裂—溶蚀”三元综合成储模式。本研究明确了四川盆地蓬莱地区超深层白云岩储集层的特征及主控因素，可为后续超深层油气资源勘探开发提供理论基础。

扬子克拉通滇中地区新元古界南沱组与陡山沱组之间过渡段“红层”不同学者认识尚有分歧。以扬子克拉通西南缘昆明晋宁鲁纳村剖面和飞大田剖面为主，对其成冰系南沱组开展了详细的地层学、沉积学研究。南沱组砾岩段及其上覆红层泥岩段具擦痕、坠石、韵律性纹层等典型冰川沉积特征，据此划分出4个沉积亚相，即冰下滞积亚相、冰缘河道亚相、冰前三角洲前缘亚相和滨岸亚相，反映了冰期演化的不同阶段。红层段顶部最年轻碎屑锆石年龄为636 Ma,表明南沱组上段紫红色粉细砂岩顶部沉积时限可能晚于636 Ma。区域地层对比发现，平面上，滇中地区南沱组砾岩段和泥岩段分布稳定；垂向上，自下而上为冰川冰下堆积砾岩，向上过渡为冰缘河道砾岩，再向上为冰前三角洲前缘泥岩和滨岸细砂岩，表现为冰川逐渐融化并逐步海侵的规律。研究认为南沱组应当二分：下段杂砾岩段，上段紫红色泥岩段，即南沱组—陡山沱组界限置于红层段顶部。论文深化了对扬子西南缘成冰纪沉积古地理的理解，为完善四川盆地周缘成冰纪—埃迪卡拉纪等时地层格架和四川盆地及周缘深层油气勘探提供了沉积学新资料。

淮河是一条对华夏文明具有重大意义的河流。但相较于黄河与长江流域，淮河流域的考古及古环境研究较为滞后。桥头遗址是淮河上游一处以石家河文化为主的重要遗址。本研究通过对桥头遗址区及其临近区域的地层调查和室内样品的测试分析，对该遗址生成前后的环境变化以及古洪水事件与遗址的存续关系等展开了研究。研究发现：桥头遗址生成前大约在8.1～4.6 ka BP(9.1～5.4 cal.ka BP),遗址所在至少方圆2 km的范围区一直被湖沼所覆盖；4.6 ka BP(5.4 cal.ka BP)以后，温暖湿润的气候、地势较高的湖沼相沉积高地以及紧邻作为遗址水源地的母子河等优越的自然环境，吸引了先民来桥头区域生活；4.0 ka BP的气候异常事件、3.5 ka BP(3.9 cal.ka BP)的气候波动所带来的洪水灾害和3.2 ka BP(3.6 cal.ka BP)的淮河改道等自然环境的频繁变动，使得石家河文化以后的1000年时间内遗址区不适宜人类居住。3 ka BP(3.3 cal.ka BP)之后，桥头遗址所在区域的气温逐渐升高变暖，先人再次在此定居；2.5 ka BP(1.8 cal.ka BP)后，气候的剧烈波动、洪水的频繁泛滥再次威胁到人类在桥头遗址区域生产生活，先人从此地再次迁徙。

以太湖东南岸梅堰孔湖相沉积岩心为研究对象，在AMS ¹⁴C测年数据建立可靠年代序列的基础上，利用元素地球化学指标重建太湖地区全新世以来气候变化，并进行盐度与有孔虫分析以探究太湖东南岸是否受到海侵影响。结果表明：11—9.1 cal.ka BP太湖地区气候由湿润逐渐转向干旱；9.1—6.1 cal.ka BP气候整体湿润，其中8.8—7.1 cal.ka BP阶段是最湿润时期；6.1—2.0 cal.ka BP降水最少，气候偏干；2.0—0 cal.ka BP降水逐渐增多，气候湿润。整个全新世阶段太湖东南岸受海侵影响的可能性较低。区域对比结果表明，中晚全新世太湖流域沉积记录与邻近地区其他研究结果具有较高的相似性，具体表现为中全新世气候趋于干旱，2.0 cal.ka BP以来气候湿润。进一步将太湖流域环境代用指标与太阳辐射和厄尔尼诺频次记录综合分析，发现研究区气候受控于太阳辐射和厄尔尼诺频次变化，且二者存在不同的主导和耦合阶段。太阳辐射通过直接和间接作用影响着太湖地区早中全新世气候，2.0 cal.ka BP以来气候呈现厄尔尼诺态，厄尔尼诺频次增强平衡了太阳辐射减弱对季风区降水的影响，成为太湖地区气候的主控因子。

显生宙的白云石化强度波动与地质历史时期重大地质事件存在高度关联性，且白云石化强度波动机制在镁、碳长期循环和气候长期变化等方面的研究中日益重要。本研究以渤海湾盆地中始新统沙三下亚段为例，针对高分辨率的X射线全岩衍射分析数据开展时间序列分析以及耦合关系分析，揭示出渤海湾盆地沙河街组深水白云石旋回中记录的斜率振幅调制周期。结合土耳其Van湖第四系白云石旋回和二叠纪与三叠纪之交白云石化事件，初步探讨了显生宙地层中不同时间尺度的深水白云石化强度波动趋势与天文旋回的耦合关系。基于沙三下亚段盐度演化特征分析，推测地球轨道参数的振幅调制作用可能通过气候、环境波动影响微生物生态压力以及流体温度与pH值波动强度，从而进一步调控显生宙轨道尺度的深水白云石化强度。本研究为“白云石问题”的探索提供了一个新颖的视角。

南海西部Y盆地L地区中新统地层呈高温、超高压特征，钻井难度大、取心资料少，岩屑录井反映岩性的精度较低，难以满足岩性精细识别的要求。以Y盆地L地区黄流组二段深层复杂碎屑岩为例，首先，利用有限的壁心粒度分析、录井、测井等资料，优选出表征岩性的粒度参数：粒度中值Md和对粒度变化敏感的自然伽马、密度、中子、声波时差、电阻率5条测井曲线，构建粒度中值Md-测井5变量数据集；其次，采用K-MEANS聚类方法，将数据集根据“误差平方和与聚类数”最优关系划分成了4类(简称“粒度分类”),分类后优化了粒度中值Md与测井响应的相关性，且获得不同类别的测井响应特征和相应岩性类型；然后，在实际井资料处理过程中，应用Fisher判别方程来判别未知深度点所属的粒度分类类型；最后，建立粒度分类下基于XGBoost算法的粒度中值测井智能计算模型，依据不同岩性对应粒度中值的数值范围，实现了井筒剖面上根据测井反演粒度中值Md曲线进而达到岩性精细识别的目的。研究结果表明：L地区黄流组二段考虑粒径的差异将砂岩岩性划分为：粉砂岩、细砂岩、中砂岩、粗砂岩，其中细砂岩和中砂岩是最主体发育的岩性，粒度中值Md与不同粒径岩性的关系最密切，是最能反映不同粒径岩性的粒度参数；粒度分类后基于XGBoost算法的粒度中值测井智能计算模型预测效果优于多元回归预测模型，计算粒度中值与实测值的相关系数达0.9397,平均绝对误差MAE为0.0195 mm,平均相对误差MRE为17.52%。该模型是一种有效实现深层复杂碎屑岩岩性精细识别的方法，也为纵向剖面上沉积粒序分析和储层构型精细解释、有效性评价奠定了基础。

豹皮（斑）灰岩是华北寒武系—奥陶系广泛发育的一种特殊形貌的海相碳酸盐岩，因具有显著的识别特征和成因机制而备受关注。鄂尔多斯盆地中奥陶统马家沟组四段发育丰富的豹皮（斑）碳酸盐岩，目前已在其中识别出遗迹化石7属8种，分别是Thalssinoides network,Thalassinoides boxwork,Planolites isp.,Palaeophycus tubularis,Phycodes isp.,Chondrites isp.,Skolithos isp., Zoophycos isp.,其以Thalassinoides的2种形态类型（水平迷宫形network和三维箱状结构boxwork）占主导，属于固底底质条件的Glossifungites遗迹相。通过野外露头、岩心的宏观和微观观察，系统调研前人关于生物扰动成因碳酸盐岩的类型，依据生物扰动、生物潜穴形态特征和方解石/白云石相对含量，笔者提出了生物扰动成因豹皮（斑）状碳酸盐岩的分类方案，将其主要分为豹皮灰岩和豹斑云岩2个大类，分别对应Thalassinoides network（水平二维迷宫）和Thalassinoides boxwork（三维箱状结构）2种形态类型。鄂尔多斯盆地马家沟组四段的豹皮（斑）状碳酸盐岩主要受生物扰动和高频海平面升降下的早期成岩作用耦合控制，表现为在固底底质条件下，生物潜穴为富Mg²⁺卤水的白云石化流体提供了良好的运移通道，使得潜穴内部优先发生白云石化作用，而不同类型的生物潜穴及准同生和埋藏白云石化作用，最终形成了豹皮灰岩和豹斑云岩这2种类型的生物扰动成因豹皮（斑）状碳酸盐岩。

羌塘盆地下侏罗统曲色组是重要的烃源岩层系，但目前对该套烃源岩中有机质富集机理仍缺乏系统研究，制约了对该区油气成藏物质基础的认识。以羌塘盆地南羌塘坳陷毕洛错地区下侏罗统曲色组厚度约100 m的富有机质页岩为研究对象，综合岩心、TOC、主量元素和微量元素等数据，系统研究了页岩沉积时的古环境和古气候特征，分析了页岩中有机质富集的主控因素，建立了该区曲色组页岩有机质的差异富集模式。结果表明，页岩有机质含量具有2段性，2段有机质含量均呈自下而上递增趋势，其中下段(59～110 m)有机质含量总体较低(TOC处于0.3%～8.1%之间，均值为2.7%),包含3层薄层富有机质段；而上段(0～59 m)有机质含量相对较高(TOC处于0.8%～16%之间，均值为4.9%)。曲色组沉积时期总体为潮湿气候环境，并受到热液作用的影响，下段的有机质富集主要与适量的陆源输入、氧化还原条件和古生产力有关；上段的有机质富集主要受控于氧化还原条件和古生产力。曲色组上段与下段有机质富集机理的差异可能与古气候和海平面变化的驱动密切相关。

珠江口盆地顺德凹陷始新统文昌组发育3套有利烃源岩，但对其层系归属、优质烃源岩特征和发育模式认识不清晰。基于高分辨率三维地震、钻井和地球化学资料，开展文昌组层序地层划分、梳理烃源岩发育特征、明确有机质富集主控因素并建立优质烃源岩发育模式。结果表明：顺德凹陷始新统文昌组可划分为3个三级层序，其中层序SQ2对应文昌组二段，烃源岩岩相类型以褐黑色、灰黑色纹层状页岩为主，有机质丰度较高，为优质烃源岩发育的主要时期。层序SQ1和SQ3分别对应文昌组三段和一段，烃源岩岩相以深灰色块状泥岩夹粉砂质泥岩为主，有机质丰度相对较低，主要发育一般烃源岩。有机质母源类型以陆源高等植物和水生浮游生物混源为主，其中层序SQ2时期藻类贡献较大。文昌组优质烃源岩发育受构造作用—古气候耦合约束，有机质富集主控因素为古生产力和古氧化还原条件。层序SQ2时期强断陷作用加剧火山活动，火山灰尘稳定沉降驱动古生产力较高；强烈的构造沉降及温暖—湿润的古气候促使湖平面上升，温度控制下的水体分层导致湖泊底水缺氧，于半深湖环境沉积厚层富有机质页岩。

玛湖凹陷二叠系风城组是准噶尔盆地近年来页岩油勘探开发和增储上产的重点层位。哈拉阿拉特山地区(简称哈山地区)位于玛湖凹陷北缘，由于位于逆冲带附近且处于勘探早期，该区风城组的沉积背景、古地理位置及页岩油勘探潜力尚不明确。根据哈山地区风城组页岩油近10年的勘探开发基础资料和成果，系统梳理了该区页岩的沉积环境、岩相划分、源岩品质、含油性和储集性，探讨了哈山地区页岩油的“甜点”发育规律和勘探前景。结果表明：玛湖主体洼陷之外，哈山地区中部风城组发育另一个碱湖沉积沉降中心，其火山喷发、沉积演化和成碱阶段与南部乌夏地区具有很好的可比性，为风城组另一富烃凹陷；提出了风城组碱湖页岩四端元对三角页岩划分方案，将风城组页岩划分为含盐和非含盐8种页岩岩相；整体上，哈山地区风城组黏土质页岩和钙质页岩有机质丰度最高，云质页岩和盐质页岩含油性相对较好，云质页岩和粉砂岩储集性最好，提出了云质页岩为I类甜点，粉砂岩为Ⅱ类甜点。哈山地区风城组页岩在源岩和储集层品质方面与乌夏地区风城组相当，具有较好的页岩油勘探前景。

陆相优质烃源岩发育大多与湖泊咸化相关，但湖泊咸化对页岩发育的影响仍不清晰。以东营凹陷古近系页岩重点取心井樊42井为例，通过岩石薄片观察、XRD、岩石热解测试、XRF二维元素扫描、微量元素测试等分析，结合有机地球化学测试数据、微量元素含量的垂向变化等，分析不同盐度演化阶段页岩成分、纹层结构、有机质丰度的变化。结果表明，研究区目的层段页岩可划分为5种岩相类型。目的层段环境演化可以划分为5个阶段，受控于气候、陆源输入等因素。古气候在沙三下亚段沉积时期呈现暖湿—相对湿冷—暖湿—相对干冷—相对暖湿的变化特征。陆源输入量呈多期旋回变化。不同类型岩石的沉积环境特征各异，高盐度的湖泊水体营养盐浓度高，具有较高的初级生产力，水体分层强烈，水体循环较弱。氧/盐度跃层位置相对较高，富氧带水深较浅，使得有机质更快脱离氧化环境沉降进入还原性水体，有利于有机质的保存。碳酸盐矿物含量高，且呈纹层状发育于滞水层中。