Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving f...Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history.展开更多
Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological sign...Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological significance of calcite veins in shales of the Cretaceous Qingshankou Formation in the Songliao Basin were investigated.Macroscopically,the calcite veins are bedding parallel,and show lenticular,S-shaped,cone-in-cone and pinnate structures.Microscopically,they can be divided into syntaxial blocky or columnar calcite veins and antitaxial fibrous calcite veins.The aqueous fluid inclusions in blocky calcite veins have a homogenization temperature of 132.5–145.1℃,the in-situ U-Pb dating age of blocky calcite veins is(69.9±5.2)Ma,suggesting that the middle maturity period of source rocks and the conventional oil formation period in the Qingshankou Formation are the sedimentary period of Mingshui Formation in Late Cretaceous.The aqueous fluid inclusions in fibrous calcite veins with the homogenization temperature of 141.2–157.4℃,yields the U-Pb age of(44.7±6.9)Ma,indicating that the middle-high maturity period of source rocks and the Gulong shale oil formation period in the Qingshankou Formation are the sedimentary period of Paleocene Yi'an Formaiton.The syntaxial blocky or columnar calcite veins were formed sensitively to the diagenetic evolution and hydrocarbon generation,mainly in three stages(fracture opening,vein-forming fluid filling,and vein growth).Tectonic extrusion activities and fluid overpressure are induction factors for the formation of fractures,and vein-forming fluid flows mainly as diffusion in a short distance.These veins generally follow a competitive growth mode.The antitaxial fibrous calcite veins were formed under the driving of the force of crystallization in a non-competitive growth environment.It is considered that the calcite veins in organic-rich shale of the Qingshankou Formation in the study area has important implications for local tectonic activities,fluid overpressure,hydrocarbon generation and expulsion,and diagenesis-hydrocarbon accumulation dating of the Songliao Basin.展开更多
The effects of major veins severing on morphological and physiological features of sweetgum （Liquidambar styraciflua L.） leaves were investigated by observing leaf color change and measuring leaf temperature, green/...The effects of major veins severing on morphological and physiological features of sweetgum （Liquidambar styraciflua L.） leaves were investigated by observing leaf color change and measuring leaf temperature, green/luminance （G/L） value of half-lobes, leaf stomata conductance, and water content in Yamaguchi University, Japan. The palmately veined leaves of sweetgum （Liquidambar styraciflua L.） were found more sensitive to the major vein severing than that of other species Major veins severing resulted in serious water stresses, as indicated by the persistent reddening and/or advanced reddening of local leaf, lower leaf stomatal conductance, and higher leaf temperature, etc. Severed leaf can be clearly divided into non-severed area, transitional area, and stressed area, which the three areas have different colours and temperature. The major vein barrier can also be seen clearly. The persistent reddening and advanced reddening seem consistent with the phenomenon of red crown top of some sweetgum trees and may have similar mechanism.展开更多
Turn-milling which history dates from the end of the 20th century is one of the advanced metal cutting technologies. It could precisely machine hard materials as an alternative to turning for certain limitations. A se...Turn-milling which history dates from the end of the 20th century is one of the advanced metal cutting technologies. It could precisely machine hard materials as an alternative to turning for certain limitations. A series of orthogonal turn-milling surface veins experiments have been done on the turn-milling machining center by machining aluminum alloy,and then the nexus between the surface veins and the cutting regimes is studied. The mathematical model for surface vein direction angle is established,also the forming mechanics of surface vein direction is analyzed. Its variety regulation presents decreasing trend with as axial feed and cutter rotary speed increasing. For different eccentric distance of orthogonal turn-milling,the surface veins are different.展开更多
The relationship between fracture calcite veins and shale gas enrichment in the deep Ordovician Wufeng Formation-Silurian Longmaxi Formation (Wufeng-Longmaxi) shales in southern Sichuan Basin was investigated through ...The relationship between fracture calcite veins and shale gas enrichment in the deep Ordovician Wufeng Formation-Silurian Longmaxi Formation (Wufeng-Longmaxi) shales in southern Sichuan Basin was investigated through core and thin section observations, cathodoluminescence analysis, isotopic geochemistry analysis, fluid inclusion testing, and basin simulation. Tectonic fracture calcite veins mainly in the undulating part of the structure and non-tectonic fracture calcite veins are mainly formed in the gentle part of the structure. The latter, mainly induced by hydrocarbon generation, occurred at the stage of peak oil and gas generation, while the former turned up with the formation of Luzhou paleouplift during the Indosinian. Under the influence of hydrocarbon generation pressurization process, fractures were opened and closed frequently, and oil and gas episodic activities are recorded by veins. The formation pressure coefficient at the maximum paleodepth exceeds 2.0. The formation uplift stage after the Late Yanshanian is the key period for shale gas migration. Shale gas migrates along the bedding to the high part of the structure. The greater the structural fluctuation is, the more intense the shale gas migration activity is, and the loss is more. The gentler the formation is, the weaker the shale gas migration activity is, and the loss is less. The shale gas enrichment in the core of gentle anticlines and gentle synclines is relatively higher.展开更多
Objective:To evaluate the effectiveness of endovenous laser therapy and conventional thera- py on the varicose of great saphenous vein.Methods:Thirty-two patients received endovenous laser thera- py and 32 patients we...Objective:To evaluate the effectiveness of endovenous laser therapy and conventional thera- py on the varicose of great saphenous vein.Methods:Thirty-two patients received endovenous laser thera- py and 32 patients were operated by conventional therapy(high ligation and stripping).The observation results of great saphenous vein(GSV)were recorded by clinical evaluation and duplex ultrasound examina- tion.And the operating time,intraoperative blood loss,time to become moveable,duration of hospitaliza- tion and degree of feeling pain were compared between the two groups.Results:Compared with conven- tional therapy,laser therapy had good curative effect with less complications and no scars and no pains. There were significant differences between the two groups(P<0.01).Conclusion:Laser therapy for varicose of great saphenous vein is better than the conventional therapy.It deserves to be widely used in clinical treatment.展开更多
Objective To investigate the safety and efficacy of a 3-pulmonary vein (PV) isolation approach in treating paroxysmal atrial fibrillation (AF). Methods Radiofrequency catheter ablation was used to eliminate PV potenti...Objective To investigate the safety and efficacy of a 3-pulmonary vein (PV) isolation approach in treating paroxysmal atrial fibrillation (AF). Methods Radiofrequency catheter ablation was used to eliminate PV potential in 11 patterns with frequent paroxysmal AF refractory to anti-arrhythmic agents. During sinus rhythm, PV potential was mapped in the left and right superior PVs and left inferior PV. The procedural success was defined as the elimination of PV potential in the 3 PVs. Restults PV potential was identified and abolished in a total of 24 PVs, mostly in the left and right superior PV. There was no pulmonary stenosis or other complications during or after the procedures. AF recurred in one patient after an average of 12 ± 3 month follow-up. Conclusions PV potemials were present mostly in the left or right superior PV. The 3-PVs isolation approach is safe and effective in preventing drug-resistant paroxysmal AF.展开更多
Objective: To evaluate the enhancement characteristics of the hepatic parenchyma during scanning with computed tomography (CT) during splenoportography (CTSP). Methods: Thirty patients refferred for CTSP were included...Objective: To evaluate the enhancement characteristics of the hepatic parenchyma during scanning with computed tomography (CT) during splenoportography (CTSP). Methods: Thirty patients refferred for CTSP were included in the study. Attenuation was measured at different time after contrast medium injection, and time-attenuation curves were created. Enhancement characteristics were evaluated, and the parenchyma-to-tumor difference of attenuation were compared. Results: CTSP led to high parenchymal enhancement. The highest enhancement value in the left lobe was (218. 0±53. 2) Hu and (246. 0±60. 2) Hu in the right lobe. The difference between the right and left lobes was statistically significant (P<0. 05); The parenchyma-to-tumor difference of (65. 3±25. 6) Hu was observed during scanning after injection. Conclusion: The high levels of liver parenchymal enhancement and parenchyma-to-lesion contrast can be achieved within the scanning time with CTSP.展开更多
基金the support of the National Natural Science Foundation of China(project number:41572123)。
文摘Lamellar calcite veins are prevalent in carbonate-rich,lacustrine dark shale.The formation mechanisms of these veins have been extensively debated,focusing on factors such as timing,depth,material source,and driving forces.This paper examines dark lacustrine shale lamellar calcite veins in the Paleogene strata of Dongying Depression,using various analytical techniques:petrography,isotope geochemistry,cathodoluminescence,inclusion thermometry,and electron probe micro-analysis.Two distinct types of calcite veins have been identified:granular calcite veins and sparry calcite veins.These two types differ significantly in color,grain structure,morphology,and inclusions.Through further investigation,it was observed that vein generation occurred from the shallow burial period to the maturation of organic matter,with a transition from granular calcite veins to sparry calcite veins.The granular calcite veins exhibit characteristics associated with the shallow burial period,including plastically deformed laminae and veins,the development of strawberry pyrite,the absence of oil and gas,weak fractionation in oxygen isotopes,and their contact relationship with sparry calcite veins.These granular calcite veins were likely influenced by the reduction of sulfate bacteria.On the other hand,sparry calcite veins with fibrous grains are antitaxial and closely linked to the evolution and maturation of organic matter.They contain oil and gas inclusions and show a distribution range of homogenization temperature between 90℃ and 120℃ and strong fractionation in oxygen isotopes,indicating formation during the hydrocarbon expulsion period.The carbon isotope analysis of the surrounding rocks and veins suggests that the material for vein formation originates from the shale itself,specifically authigenic micritic calcite modified by the action of methanogens.The opening of horizontal fractures and vein formation is likely driven by fluid overpressure resulting from undercompaction and hydrocarbon expulsion.Veins may form rapidly or through multi-stage composite processes.Early veins are predominantly formed in situ,while late veins are a result of continuous fluid migration and convergence.Furthermore,the veins continue to undergo modification even after formation.This study emphasizes that the formation of lamellar calcite veins in shale is a complex diagenetic process influenced by multiple factors:biology,organic matter,and inorganic processes,all operating at various stages throughout the shale's diagenetic history.
基金Supported by the Natural Science Foundation of Hebei(D2024501002)Fundamental Research Funds for the Central Universities(N2423020)Major Science and Technology Projects of CNPC(2021ZZ10)。
文摘Based on the observation and analysis of cores and thin sections,and combined with cathodoluminescence,laser Raman,fluid inclusions,and in-situ LA-ICP-MS U-Pb dating,the genetic mechanism and petroleum geological significance of calcite veins in shales of the Cretaceous Qingshankou Formation in the Songliao Basin were investigated.Macroscopically,the calcite veins are bedding parallel,and show lenticular,S-shaped,cone-in-cone and pinnate structures.Microscopically,they can be divided into syntaxial blocky or columnar calcite veins and antitaxial fibrous calcite veins.The aqueous fluid inclusions in blocky calcite veins have a homogenization temperature of 132.5–145.1℃,the in-situ U-Pb dating age of blocky calcite veins is(69.9±5.2)Ma,suggesting that the middle maturity period of source rocks and the conventional oil formation period in the Qingshankou Formation are the sedimentary period of Mingshui Formation in Late Cretaceous.The aqueous fluid inclusions in fibrous calcite veins with the homogenization temperature of 141.2–157.4℃,yields the U-Pb age of(44.7±6.9)Ma,indicating that the middle-high maturity period of source rocks and the Gulong shale oil formation period in the Qingshankou Formation are the sedimentary period of Paleocene Yi'an Formaiton.The syntaxial blocky or columnar calcite veins were formed sensitively to the diagenetic evolution and hydrocarbon generation,mainly in three stages(fracture opening,vein-forming fluid filling,and vein growth).Tectonic extrusion activities and fluid overpressure are induction factors for the formation of fractures,and vein-forming fluid flows mainly as diffusion in a short distance.These veins generally follow a competitive growth mode.The antitaxial fibrous calcite veins were formed under the driving of the force of crystallization in a non-competitive growth environment.It is considered that the calcite veins in organic-rich shale of the Qingshankou Formation in the study area has important implications for local tectonic activities,fluid overpressure,hydrocarbon generation and expulsion,and diagenesis-hydrocarbon accumulation dating of the Songliao Basin.
文摘The effects of major veins severing on morphological and physiological features of sweetgum （Liquidambar styraciflua L.） leaves were investigated by observing leaf color change and measuring leaf temperature, green/luminance （G/L） value of half-lobes, leaf stomata conductance, and water content in Yamaguchi University, Japan. The palmately veined leaves of sweetgum （Liquidambar styraciflua L.） were found more sensitive to the major vein severing than that of other species Major veins severing resulted in serious water stresses, as indicated by the persistent reddening and/or advanced reddening of local leaf, lower leaf stomatal conductance, and higher leaf temperature, etc. Severed leaf can be clearly divided into non-severed area, transitional area, and stressed area, which the three areas have different colours and temperature. The major vein barrier can also be seen clearly. The persistent reddening and advanced reddening seem consistent with the phenomenon of red crown top of some sweetgum trees and may have similar mechanism.
基金Sponsored by Doctoral Science Foundation of Shenyang Ligong University (BS04007)
文摘Turn-milling which history dates from the end of the 20th century is one of the advanced metal cutting technologies. It could precisely machine hard materials as an alternative to turning for certain limitations. A series of orthogonal turn-milling surface veins experiments have been done on the turn-milling machining center by machining aluminum alloy,and then the nexus between the surface veins and the cutting regimes is studied. The mathematical model for surface vein direction angle is established,also the forming mechanics of surface vein direction is analyzed. Its variety regulation presents decreasing trend with as axial feed and cutter rotary speed increasing. For different eccentric distance of orthogonal turn-milling,the surface veins are different.
基金Supported by the PetroChina Science and Technology Project(2022KT1205).
文摘The relationship between fracture calcite veins and shale gas enrichment in the deep Ordovician Wufeng Formation-Silurian Longmaxi Formation (Wufeng-Longmaxi) shales in southern Sichuan Basin was investigated through core and thin section observations, cathodoluminescence analysis, isotopic geochemistry analysis, fluid inclusion testing, and basin simulation. Tectonic fracture calcite veins mainly in the undulating part of the structure and non-tectonic fracture calcite veins are mainly formed in the gentle part of the structure. The latter, mainly induced by hydrocarbon generation, occurred at the stage of peak oil and gas generation, while the former turned up with the formation of Luzhou paleouplift during the Indosinian. Under the influence of hydrocarbon generation pressurization process, fractures were opened and closed frequently, and oil and gas episodic activities are recorded by veins. The formation pressure coefficient at the maximum paleodepth exceeds 2.0. The formation uplift stage after the Late Yanshanian is the key period for shale gas migration. Shale gas migrates along the bedding to the high part of the structure. The greater the structural fluctuation is, the more intense the shale gas migration activity is, and the loss is more. The gentler the formation is, the weaker the shale gas migration activity is, and the loss is less. The shale gas enrichment in the core of gentle anticlines and gentle synclines is relatively higher.
文摘Objective:To evaluate the effectiveness of endovenous laser therapy and conventional thera- py on the varicose of great saphenous vein.Methods:Thirty-two patients received endovenous laser thera- py and 32 patients were operated by conventional therapy(high ligation and stripping).The observation results of great saphenous vein(GSV)were recorded by clinical evaluation and duplex ultrasound examina- tion.And the operating time,intraoperative blood loss,time to become moveable,duration of hospitaliza- tion and degree of feeling pain were compared between the two groups.Results:Compared with conven- tional therapy,laser therapy had good curative effect with less complications and no scars and no pains. There were significant differences between the two groups(P<0.01).Conclusion:Laser therapy for varicose of great saphenous vein is better than the conventional therapy.It deserves to be widely used in clinical treatment.
文摘Objective To investigate the safety and efficacy of a 3-pulmonary vein (PV) isolation approach in treating paroxysmal atrial fibrillation (AF). Methods Radiofrequency catheter ablation was used to eliminate PV potential in 11 patterns with frequent paroxysmal AF refractory to anti-arrhythmic agents. During sinus rhythm, PV potential was mapped in the left and right superior PVs and left inferior PV. The procedural success was defined as the elimination of PV potential in the 3 PVs. Restults PV potential was identified and abolished in a total of 24 PVs, mostly in the left and right superior PV. There was no pulmonary stenosis or other complications during or after the procedures. AF recurred in one patient after an average of 12 ± 3 month follow-up. Conclusions PV potemials were present mostly in the left or right superior PV. The 3-PVs isolation approach is safe and effective in preventing drug-resistant paroxysmal AF.
文摘Objective: To evaluate the enhancement characteristics of the hepatic parenchyma during scanning with computed tomography (CT) during splenoportography (CTSP). Methods: Thirty patients refferred for CTSP were included in the study. Attenuation was measured at different time after contrast medium injection, and time-attenuation curves were created. Enhancement characteristics were evaluated, and the parenchyma-to-tumor difference of attenuation were compared. Results: CTSP led to high parenchymal enhancement. The highest enhancement value in the left lobe was (218. 0±53. 2) Hu and (246. 0±60. 2) Hu in the right lobe. The difference between the right and left lobes was statistically significant (P<0. 05); The parenchyma-to-tumor difference of (65. 3±25. 6) Hu was observed during scanning after injection. Conclusion: The high levels of liver parenchymal enhancement and parenchyma-to-lesion contrast can be achieved within the scanning time with CTSP.
