期刊文献+
共找到408篇文章
< 1 2 21 >
每页显示 20 50 100
Metamorphism of the northern Liaoning Complex:Implications for the tectonic evolution of Neoarchean basement of the Eastern Block,North China Craton 被引量:13
1
作者 Kam Kuen Wu Guochun Zhao +3 位作者 Min Sun Changqing Yin Yanhong He Pui Yuk Tam 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期305-320,共16页
As one of the areas where typical late Archean crust is exposed in the Eastern Block of the North China Craton, the northern Laioning Complex consists principally of tonalitic-trondhjemitic-granodioritic (TTG) gneis... As one of the areas where typical late Archean crust is exposed in the Eastern Block of the North China Craton, the northern Laioning Complex consists principally of tonalitic-trondhjemitic-granodioritic (TTG) gneisses, massive granitoids and supracrustal rocks. The supracrustal rocks, named the Qingyuan Group, consist of interbedded amphibolite, hornblende granulite, biotite granulite and BIF. Petrological evidence indicates that the amphibolites experienced the early prograde (M1), peak (M2) and post-peak (M3) metamorphism. The early prograde assemblage (M1) is preserved as mineral inclusions, represented by actinotite + hornblende - plagioclase + epidote + quartz 4- sphene, within garnet porphyroblasts. The peak assemblage (M2) is indicated by garnet + clinopyroxene + hornblende + plagioclase + quartz + ilmenite, which occur as major mineral phases in the rock. The post-peak assemblage (M3) is characterized by the garnet 4- quartz symplectite. The P-T pseudosections in the NCFMASHTO system constructed by using THERMOCALC define the P-T conditions of M1, M2 and M3 at 490-550 C+(4.5 kbar, 780 810 C/7.65- 8.40 kbar and 630-670 +C]8.15-9.40 kbar, respectively. As a result, an anticlockwise P-T path involving isobaric cooling is inferred for the metamorphic evolution of the amphibolites. Such a P-T path suggests that the late Archean metamorphism of the northern Liaoning Complex was related to the intrusion and underplating of mantle-derived magmas. The underplating of voluminous mantle-derived magmas leading to metamorphism with an anticlockwise P-T path involving isobaric cooling may have occurred in continental magmatic arc regions, above hot spots driven by mantle plumes, or in continental rift envi- ronments. A mantle plume model is favored because this model can reasonably interpret many other geological features of late Archean basement rocks from the northern Liaoning Complex in the Eastern Block of the North China Craton as well as their anticlockwise P-T paths involving isobaric cooling. 展开更多
关键词 Amphibolites Northern Liaoning complex North china Craton Late Archean Metamorphic evolution
下载PDF
U-Pb Age and Hf Isotope Study of Detrital Zircons from the Wanzi Supracrustals:Constraints on the Tectonic Setting and Evolution of the Fuping Complex,Trans-North China Orogen 被引量:12
2
作者 Xiaoping XIA Min SUN +5 位作者 Guochun ZHAO WU Fuyuan XU Ping Jian ZHANG Yanhong HE ZHANG Jiheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期844-863,共20页
Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of v... Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of various high-grade and multiply deformed rocks, including gray gneiss, basic granulite, amphibolite, fine-grained gneiss and marble, metamorphosed to upper amphibolite or granulite facies. It can be divided into four rock units: the Fuping TTG gneisses, Longquanguan augen gneisses, Wanzi supracrustals, and Nanying granitic gneisses. U-Pb age and Hf isotope compositions of about 200 detrital zircons from the Wanzi supracrustals of the Fuping Complex have been analyzed. The data on metamorphic zircon rims give ages of 1.82-1.84 Ga, corresponding to the final amalgamation event of the NCC, whereas the data for igneous zircon cores yield two age populations at -2.10 and -2.51 Ga, with some inherited ages scattering between 2.5 and 2.9 Ga. These results suggest that the Wanzi supracrustals were derived from the Fuping TTG gneisses (-2.5 Ga) and the Nanying granitic gneisses (2.0-2.1 Ga) and deposited between 2.10 and 1.84 Ga. All zircons with -2.51 Ga age have positive initial εHf values from +1.4 to +10.9, suggesting an important crustal growth event at -2.5 Ga through the addition of juvenile materials from the mantle. The Hf isotope data for the detrital zircons further imply that the 2.8 Ga rocks are important components in the lower crust, which is consistent with a suggestion from Nd isotope data for the Eastern Block. The zircons of 2.10 Ga population have initial εHf values of-4.9 to +6.1, interpreted as mixing of crustal re-melt with minor juvenile material contribution at 2.1 Ga. These results are distinct from that for the Western Block, supporting that the Fuping Complex was emplaced in a tectonic active environment at the western margin of the Eastern Block. 展开更多
关键词 detrital zircons U-Pb age and Hf isotope Fuping complex North china Craton
下载PDF
Isotopic Geochronology of the Xianghongdian Alkaline Complex, Northern Margin of the Dabie Mountains, China 被引量:6
3
作者 YANG Zhuliang SHEN Weizhou +2 位作者 SHEN Jialin TAO Kuiyuan XIE Fanggui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第4期404-410,共7页
To the north of the Qinling-Dabie orogen there exists a Mesozoic (K1) granite-syenite belt called the Beihuaiyang granite-syenite belt, in which the Xianghongdian alkaline complex outcrops in the Devonian Foziling sch... To the north of the Qinling-Dabie orogen there exists a Mesozoic (K1) granite-syenite belt called the Beihuaiyang granite-syenite belt, in which the Xianghongdian alkaline complex outcrops in the Devonian Foziling schist and also intruded into the slightly earlier volcanic rocks. This alkaline complex is composed of syenite, alkaline syenite and nepheline syenite, but the nepheline syenite occurs inside the alkaline syenite in the pod-like, irregular, lenticular or layered shape. Researches on the petrogenesis of the alkaline complex and the relationship between the alkaline syenite and the nepheline syenite must rely on precise isotopic ages. Previous researches have reported isotopic dating results merely by the 40Ar/39Ar method on hornblende and biotite separated from the alkaline syenite and nepheline syenite. In view of this, the authors have made fairly detailed isotopic geochronological studies of the alkaline syenite and nepheline syenite by using Rb-Sr isochron for the whole rock and minerals, U-Pb for single zircon separate and the 40Ar/39Ar method for hornblende and potash feldspar. The results of this research are completely different from those of previous researches and show that the nepheline syenite was formed far earlier than the alkaline syenite. 展开更多
关键词 isotopic geochronology alkaline complex Xianghongdian Dabie Mountains china
下载PDF
Cu-An Metallogenic Series Related to Volcanic-Intrusive Complexes in Eastern China 被引量:4
4
作者 Zhai Yusheng(Department of Geology and Mineral Resources, China University of Geosciences,Beijing 100083)Yao Shuzhen(Faculty of Earth Resources, China University Of Geosciences,Wuhan 430074) 《Journal of Earth Science》 SCIE CAS CSCD 1995年第1期107-113,共7页
The Cu - An co - existence ore deposits related to intermediate- acidic volcanic - intrusive complexes are widespread in eastern China. They can be divided into 5 types: (1) sharn type, (2 )porphyry type, (3)vein type... The Cu - An co - existence ore deposits related to intermediate- acidic volcanic - intrusive complexes are widespread in eastern China. They can be divided into 5 types: (1) sharn type, (2 )porphyry type, (3)vein type, (4 )breccia pipe type and (5)stratabound type. All of those have intimate spatial, temporal and genetic relations formed by the Mesozoic tertonicmatic - hydrothermal activities in certain geological environments. The magmatic and Cu-An metallogenic ager were predominately in Late Mesozoic (179-90 Ma), and in the period of 150-120 Ma the ore-forming Processes reached the Peak. The main geological Settings of Cu-An ore-forming Processes are: (1) continental margins, including the Peripheral depression of the continental Plate, (2) deep fault zones in the continental Plate,(3)continental rift belt. The magmatic activities were under the combined control of basement fault (s )and superficial fault (s ), and mostly formed the continental volcanic basins. The regional Cu-An metallogenic zones occur along the deep fault zones in WNW - EW direction,such as the Tongling metallogenic subzone, or in NE-NNE direction, such as the Dexing metallogenic subzone. Most of Cu- An ore deposits are related to subvolcanic stocks consist of quartz diorite, granodiorite, quartz porphyry, andesite porphyry, trachyte porphyry and other rocks, which belong to the calc- alkaline series and the I - type granitoid. The spatial zoning of matals from the center to periphery of the stocks is: CU (Mo )→ Cu,Au→Cu, Ph, Zn,An →Ph, Zn, Ag →Ph, Ag. There is a typical venical metallic zoning (from surface to 3 000m in depth ) in Yinshan Cu-An-Ph-Zn-Ag ore deposit, northeastern Jianxi Province. 展开更多
关键词 Cu-An ore deposit metallogenic series volcanic-intrusive complex Mesozoic eastern china.
下载PDF
Guandishan Granitoids of the Paleoproterozoic Lüliang Metamorphic Complex in the Trans-North China Orogen:SHRIMP Zircon Ages,Petrogenesis and Tectonic Implications 被引量:9
5
作者 LIU Shuwen LI Qiugen LIU Chaohui LU Yongjun ZHANG Fan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2009年第3期580-602,共23页
The Paleoproterozoic Liiliang Metamorphic Complex (PLMC) is situated in the middle segment of the western margin of the Trans-North China Orogen (TNCO), North China Craton (NCC). As the most important lithologic... The Paleoproterozoic Liiliang Metamorphic Complex (PLMC) is situated in the middle segment of the western margin of the Trans-North China Orogen (TNCO), North China Craton (NCC). As the most important lithological assemblages in the southern part of the PLMC, Guandishan granitoids consist of early gneissic tonalities, granodiorites and gneissic monzogranites, and younger gneissic to massive monzogranites. Petrochemical features reveal that the early gneissic tonalities and granodiorites belong to the medium-K calc-alkaline series; the early gneissic monzogranites are transitional from high-K calc-alkaline to the shoshonite series; the younger gneissic to massive monzogranites belong to the high-k calc-alkaline series, and all rocks are characterized by right- declined REE patterns and negative Nb, Ta, Sr, P, and Ti anomalies in the primitive mantle normalized spidergrams. SHRIMP zircon U-Pb isotopic dating reveals that the early gneissic tonalities and granodiorites formed at -2.17 Ga, the early gneissic monzogranites at -2.06 Ga, and the younger gneissic to massive monzogranites at -1.84 Ga. Sm-Nd isotopic data show that the early gneissic tonalities and granodiorites have eNd(t) values of +0.48 to -3.19 with Nd-depleted mantle model ages (TDM) of 2.76--2.47 Ga, and early gneissic monzogranites have eNd(t) values of -0.53 to -2.51 with TDM of 2.61--2.43 Ga, and the younger gneissic monzogranites have eNd(t) values of -6.41 to -2.78 with a TDM of 2.69--2.52 Ga.These geochemical and isotopic data indicate that the early gneissic tonalities, granodiorites, and monzogranites were derived from the partial melting of metamorphosed basaltic and pelitic rocks, respectively, in a continental arc setting. The younger gneissic to massive monzogranites were derived by partial melting of metamorphosed greywackes within the continental crust. Combined with previously regional data, we suggest that the Paleoproterozoic granitoid magmatism in the Guandishan granitoids of the PLMC may provide the best geological signature for the complete spectrum of Paleoproterozoic geodynamic processes in the Trans-North China Orogen from oceanic subduction, through collisional orogenesis, to post-orogenic extension and uplift. 展开更多
关键词 Guandishan granitoid petrogenesis SHRIMP zircon geochronology geochemistry Ndisotopes Paleoproterozoic Liiliangshan complex Trans-North china Orogen North china craton.
下载PDF
Report of Prionospio complex(Annelida:Polychaeta:Spio-nidae) from China's waters,with description of a new species 被引量:5
6
作者 ZHOU Jin LI Xinzheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2009年第1期116-127,共12页
Nine species of Prionospio complex are recorded from China's waters,including one new species and six newly recorded species.Prionospio(Prionospio) pacifica sp.nov.,is characterized by having first and forth pairs ... Nine species of Prionospio complex are recorded from China's waters,including one new species and six newly recorded species.Prionospio(Prionospio) pacifica sp.nov.,is characterized by having first and forth pairs of branchiae pinnate,second and third pairs of apinnate,ventral crest on Setiger 9 and dorsal crests on Setigers 10-25.Apoprionospio kirrae(Wilson,1990),Prionospio(Aquilaspio) convexa Imajima,1990,Prionospio(Minuspio) multibranchiata Berkeley,1927,Prionospio(Prionospio) bocki Sderstrm,1920,Prionospio(Prionospio) dubia Maciolek,1985 and Prionospio(Prionospio) paradisea Imajima,1990 are recorded for the first time from China's waters. 展开更多
关键词 taxonomy Prionospio complex new species newly recorded species china's waters.
下载PDF
China's Fortune 500 Complex
7
作者 LiuZhouwei 《China's Foreign Trade》 1999年第11期8-9,共2页
关键词 china’s Fortune 500 complex
下载PDF
Characteristics and distribution patterns of reef complexes on the carbonate platform margin in deep water areas:the western South China Sea 被引量:3
8
作者 CHEN Ping LI Xushen +7 位作者 WANG Yahui LU Yongchao ZHONG Zehong CHEN Lei ZUO Qianmei MA Yiquan WANG Chao DU Xuebin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第10期71-80,共10页
As a potential oil and gas reservoir, reef complexes have been a research focus from petroleum geologists for a long time. There are favorable conditions for the development of reef complexes in the South China Sea; h... As a potential oil and gas reservoir, reef complexes have been a research focus from petroleum geologists for a long time. There are favorable conditions for the development of reef complexes in the South China Sea; however, their internal structures, evolution and distribution are still poorly understood. Based on 2D and 3D seismic data, the internal structures and evolution patterns of the reef complexes on the carbonate platform margin in the deep water areas over the western South China Sea were studied in detail. The result shows that two types of reef complexes, i.e., fault controlling platform margin reef complexes and ramp reef complexes have been developed in the study area. The reef complexes have independent or continuous mound or lenticular seismic reflections, with three internal structures (i.e., aggrading, prograding and retrograding structures). There are different growth rates during the evolution of the reef complexes, resulting in the formation of catch-up reefs, keep-up reefs and quick step reefs. The study also reveals that different platform margin reef complexes have different internal structures and distributions, because of the different platform types. These results may be applied to the exploration and prediction of carbonate platform margin reef complexes in other areas that are similar to the study area. 展开更多
关键词 reef complex carbonate platform margin growth evolution South china Sea
下载PDF
MORPHOLOGICAL DEVELOPMENT OF SCIENCE-INDUS- TRY COMPLEXES IN CHINA
9
作者 Chen Yisheng(CAS Institute of Policy & Management) 《Bulletin of the Chinese Academy of Sciences》 1997年第3期253-258,共6页
This paper maintains that science-industry complexes (SICs), with science parks as the grassroots units, present a tripartite structure of parks, zones and belts in their spatial layout. In their morphological system,... This paper maintains that science-industry complexes (SICs), with science parks as the grassroots units, present a tripartite structure of parks, zones and belts in their spatial layout. In their morphological system, parks act as the building bricks of the zones and belts, while the latter two are the outward expansion of parks, leading to spatial diffusion and the transfer of hi-tech knowhow and hi-tech industry. Viewed from the temporal sequence, a park is the starting point for the growth of a zone or a belt, while a zone or a belt is the evolutionary outcome of parks, reflecting sequential advances of an innovation chain.Based on this viewpoint, this paper attempts to make a case study on the morphological development of hi-tech zones and belts in this country. The paper concludes that there are two developmental patterns which Chinese SICs are destined for. One is a zone that incubates a group of parks and the other is a cluster of zones forming a belt. Such an evolutionary process results from 展开更多
关键词 MORPHOLOGICAL DEVELOPMENT OF SCIENCE-INDUS TRY complexES IN china
下载PDF
Paleoproterozoic Potassic Granitoids in the Sushui Complex from the Zhongtiao Mountains,Northern China:Geochronology,Geochemistry and Petrogenesis 被引量:14
10
作者 TIAN Wei LIU Shuwen ZHANG Huafeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期875-885,共11页
Paleoproterozoic potassic granitoids in the southern Sushui Complex from the Zhongtiao Mountains yielded SHRIMP zircon U-Pb ages of 1968-1944 Ma. Lithologically, the potassic granitoid series consists chiefly of monzo... Paleoproterozoic potassic granitoids in the southern Sushui Complex from the Zhongtiao Mountains yielded SHRIMP zircon U-Pb ages of 1968-1944 Ma. Lithologically, the potassic granitoid series consists chiefly of monzodiorite, quartz monzonite and syenogranite. Their trace elements and Sm-Nd isotope characteristics indicate that they were derived from partial melting of Archean TTG rocks in an overthickened continental crust. Petrogenesis of this potassic granitoid series implies a collisional environment within the Trans-North China Orogen in the Paleoproterozoic, which supports a tectonic model of Eastern and Western Continental Blocks being amalgamated in the Paleoproterozoic. 展开更多
关键词 Sushui complex Zhongtiao Block Trans-North china Orogen potassic granitoid zircon U-Pb Sm-Nd isotope PALEOPROTEROZOIC
下载PDF
Study on copper complexing ligand concentrations in several China's coastal waters
11
作者 GONG Haidong ZHANG Zhengbin LIU Chunying LIU Liansheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期64-77,共14页
Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regulari... Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows: Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer (SSL) in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complex- ing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China's coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly. 展开更多
关键词 copper complexing ligand concentrations china s coastal waters distribution regularity RELATIONSHIP
下载PDF
Geological characters and petrological characters of metamorphosed medium-acidic intrusive complexes in Ludong Orogenic Belt,China
12
作者 凌贤长 胡庆立 王丽霞 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第1期16-23,共8页
Ludong orogenic belt in China is an importantal continent collision orogenic belt in eastern Asia, between Sino Korean landmass and Yangtze landmass. The host rock of the orogenic belt is metamorphosed medium acidic i... Ludong orogenic belt in China is an importantal continent collision orogenic belt in eastern Asia, between Sino Korean landmass and Yangtze landmass. The host rock of the orogenic belt is metamorphosed medium acidic intrusive complexes, which can be divided into four types, that’s, quartz dioritz, granite dioritz, monzonitic granite and undertint monzonitic granite, principal minerals are plagioclases, potassium feldspars and quartzs, minor minerals are hornblendes, biotites, clinopyxenes and garnets, accessory mineral types and assemblages are very similar, specially, various rocks are mainly fine grained textures. They have the history of regional amphibolite facies metamorphism and deep middle shallow structural layer deformation, and are changed into various gneiss and tectonic system. There are many xenolithes of middle Proterozoic eclogite host rock extrahigh high pressure metamorphic complexes, a small xenolithes of early Proterozoic layered metamorphite system and granulites, and ultrabasic basic rocks of various epoches in the metamorphosed medium acidic intrusive complexes. 展开更多
关键词 Ludong OROGENIC belt in china metamorphosed MEDIUM ACIDIC INTRUSIVE complexes Sino Korean landmass yangtze landmass
下载PDF
The Gravity Flow on a Shelf-Edge-Slope-Basin-Floor Complex in Qiongdongnan Basin,Northern South China Sea
13
作者 Ming Su~1,Xinong Xie~1,Yunlong He~1,Tao Jiang~1,Chen Zhang~1,Shanshan Tian~1,Junliang Li~2 1.Faculty of Earth Resources,China University of Geosciences(Wuhan),Wuhan 430074,China. 2.Department of Technology,Zhanjiang Branch of CNOOC,Zhanjiang 524057,China 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期225-225,共1页
The Qiongdongnan Basin lies in the west part of the northern South China Sea.To the west the basin is bound by the Red River Fault and the Yinggehai Basin,to the east by the Pearl River Mouth Basin,and to the south by... The Qiongdongnan Basin lies in the west part of the northern South China Sea.To the west the basin is bound by the Red River Fault and the Yinggehai Basin,to the east by the Pearl River Mouth Basin,and to the south by the Xisha Rise.In this study,the sequence stratigraphic framework was set up and 11 third-order sequences were distinguished.Based 展开更多
关键词 gravity flow Shelf-Edge-Slope-Basin-Floor complex Qiongdongnan Basin South china Sea
下载PDF
Two–stage Cretaceous Exhumation of Hengshan Complex in Hunan Province, SE China: Constraints Arising from ^(40)Ar–^(39)Ar Geochronology and Cretaceous Tectonic Implications 被引量:2
14
作者 WANG Yanhong CUI Jianjun +5 位作者 ZHANG Yueqiao DONG Shuwen QI Wen SU Jinbao LI Jianhua LI Yong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期1869-1881,共13页
The Hengshan complex is located in the central part of SE China, which underwent rapid tectonic uplift in the Cretaceous just like many other complexes on the continent. (40)~Ar-(39)~Ar geochronological data from ... The Hengshan complex is located in the central part of SE China, which underwent rapid tectonic uplift in the Cretaceous just like many other complexes on the continent. (40)~Ar-(39)~Ar geochronological data from the Hengshan complex suggest that two episodes of crustal cooling/extension took place in this part of the continent during the Cretaceous time. The first stage of exhumation was active during ca. 136-125 Ma, with a cooling rate of 〉 10 ℃Ma. The second stage of exhumation happened at ca. 98-93 Ma, with a cooling rate of 〉 10 ℃/Ma. Considering the folding in the Lower Cretaceous sedimentary rocks and the regional unconformity underneath the Upper Cretaceous red beds, it is believed that the Cretaceous crustal extension in SE China was interrupted by a compressional event. The reversion to extension, shortly after this middle Cretaceous compression, led to the rapid cooling/exhumation of the Hengshan complex at ca. 98-93 Ma. The Cretaceous tectonic processes in the hinterland of SE China could be controlled by interactions between the continental margin and the Paleo-pacific plate. 展开更多
关键词 Hengshan complex Crustal extension Cretaceous tectonics 40Ar-39Ar geochronology SE china
下载PDF
冀北红旗营杂岩多期变质作用:古元古代俯冲/碰撞—晚古生代伸展—早中生代挤压的记录
15
作者 魏春景 赵亚男 初航 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期95-110,共16页
冀北红旗营杂岩记录了从古元古代到早中生代多期构造-热事件,并可能存在支持古元古代洋壳俯冲的关键证据,但是对其形成时代、变质演化历史和大地构造属性等众说纷纭。本文以总结红旗营杂岩变质作用和年代学研究为基础,探讨其复杂的多期... 冀北红旗营杂岩记录了从古元古代到早中生代多期构造-热事件,并可能存在支持古元古代洋壳俯冲的关键证据,但是对其形成时代、变质演化历史和大地构造属性等众说纷纭。本文以总结红旗营杂岩变质作用和年代学研究为基础,探讨其复杂的多期构造演化过程。红旗营杂岩包括表壳岩、赤城混杂岩和正片麻岩三个岩石-构造单元。正片麻岩以古元古代(1.87~1.82 Ga)花岗闪长岩-二长花岗岩-正长花岗岩为主,出现少量新太古代(2.55~2.53 Ga)英云闪长质-花岗闪长质片麻岩。赤城混杂岩为典型蛇绿混杂岩,由退变榴辉岩(斜长角闪岩)和橄榄岩块体以及变质沉积岩组成,形成时代可能>1.88 Ga。表壳岩主要包括不同变质程度的碳质碎屑岩-碳酸盐岩和少量火山岩,可能形成于2.1~2.0 Ga。综合分析赤城混杂岩中的退变榴辉岩、斜长角闪岩和凤山地区含十字石石榴云母片岩的变质作用演化,可划分出5期变质作用。第一期变质作用(M1)存在于凤山地区的云母片岩中,为中压型,顺时针型p-T轨迹,峰期变质条件为1.0~1.1 GPa/>780℃,变质时间为约1.95 Ga。第二期变质作用(M2)见于退变榴辉岩中,顺时针型p-T轨迹,包括升温升压至峰期和峰后等温降压演化阶段,峰期p-T条件为>2.2 GPa/约750℃,地热梯度约为9℃/km。尽管退变榴辉岩中多数锆石限定晚古生代变质年龄,但榴辉岩相变质作用时间应>1.88 Ga。第三期变质作用(M3)出现于凤山地区的云母片岩中,以含十字石组合叠加在M1高级变质组合为特征,顺时针型p-T轨迹,峰期变质条件为0.6~0.7 GPa/610~630℃,变质年龄约为1.88 Ga。第四期变质作用(M4)出现于赤城混杂岩的斜长角闪岩中,由早期榴辉岩组合叠加变质形成,显示“大于号”形p-T轨迹,包括峰前减压升温和峰期后减压冷却变质过程,峰期p-T条件为0.5~0.7 GPa/780~830℃,地热梯度约为35℃/km(低压型),变质时间为晚古生代(354~289 Ma),并伴随广泛深熔作用。第五期变质作用(M5)以局部叠加绿片岩相组合为特征,为顺时针型p-T轨迹,推测变质作用时间为255~234 Ma。M1中压型变质作用与在华北克拉通西部2.0~1.95 Ga发生的碰撞造山事件有关;M2高压型变质作用与沿华北克拉通北缘1.95~1.88 Ga期间发生的洋壳俯冲有关,是支持现在样式板块构造启动的有力证据之一;M3中压型变质作用指示在华北克拉通北缘于1.88~1.83 Ga期间发生的另一次碰撞造山事件;M4低压型变质作用为晚古生代华北克拉通北缘区域伸展所致;M5低温型变质作用与沿索伦缝合带发生的碰撞闭合事件有关。可见,红旗营杂岩5期变质作用记录了古元古代碰撞-俯冲-碰撞、晚古生代伸展和早中生代挤压的复杂构造过程。红旗营杂岩在经历古元古代俯冲-碰撞事件之后位于不同地壳深度。西部红旗营表壳岩和赤城混杂岩位于中-下地壳层次,其中锆石记录了1.72~1.66 Ga、约450 Ma、354~289 Ma和255~234 Ma等多期热事件;而东部凤山地区表壳岩则位于中-上地壳,缺少后期热事件的锆石和独居石年龄记录。 展开更多
关键词 多期变质作用 古元古代混杂岩 红旗营杂岩 华北克拉通
下载PDF
“中国西南储气能力”建设的技术基础与发展思考
16
作者 胡勇 王梦雨 +3 位作者 罗瑜 李隆新 彭先 赵梓寒 《天然气工业》 EI CAS CSCD 北大核心 2024年第2期1-13,共13页
为保障国家天然气安全平稳供应,2019年国家能源局启动了川渝天然气千亿立方米级“气大庆”的建设项目,将四川盆地天然气储气调峰和战略应急保供能力建设提升至国家战略安全高度。此外,中国石油在“十四五”期间确立了打造“西南储气中... 为保障国家天然气安全平稳供应,2019年国家能源局启动了川渝天然气千亿立方米级“气大庆”的建设项目,将四川盆地天然气储气调峰和战略应急保供能力建设提升至国家战略安全高度。此外,中国石油在“十四五”期间确立了打造“西南储气中心”的战略目标,积极攻关各项地下储气库(以下简称储气库)建库技术难题,已初步形成“西南储气中心”建设格局。为此,在分析四川盆地建设储气库面临的挑战基础上,系统梳理总结了中国石油近17年在四川盆地的发展规划、建设现状、技术进展等方面的成果,并对打造“中国西南储气能力”提出了具体的攻关方向。研究结果表明:(1)四川盆地天然气资源丰富且拥有与全国天然气管网互连互通的完善管网设施,能够为盆地储气库建设提供坚实基础;(2)提出了复杂盆地气藏的“十指标”选址体系,建立了完善的储气库库址优选技术;(3)形成了储气库建库运行七大特色技术,健全了碳酸盐岩气藏建库主体技术系列;(4)构建了国内首个储气库地质体、井、地面完整性管理评价技术体系,保障了储气库安全稳定运行。结论认为,为支撑国家天然气千亿立方米级“气大庆”建设,提出了“中国西南储气能力”建设的概念,其核心是以中国石油初步建成的企业级“西南储气中心”为基础,走出单一油公司储气库建设模式,建立政府主导协调、跨企业的储气库协同共建共享共营机制,全面推动四川盆地整体储气能力建设,保障国家天然气能源安全。 展开更多
关键词 中国西南储气能力 四川盆地 地下储气库 复杂气藏条件 选址 完整性管理
下载PDF
赞皇杂岩翁城地区长城系常州沟组砂岩碎屑锆石U-Pb-Hf同位素研究
17
作者 王乐乐 刘平华 +5 位作者 周万蓬 杜利林 杨崇辉 张文 曹秋香 陈丽梅 《岩石矿物学杂志》 CAS CSCD 北大核心 2024年第3期737-775,共39页
常州沟组是华北克拉通太古宙-古元古代变质基底上最早的沉积盖层之一,其碎屑锆石U-Pb年代学与Hf同位素特征分析对探讨长城系形成时代、源区特征以及基底演化均具有重要的研究意义。本文对华北克拉通中部赞皇杂岩瓮城地区长城系常州沟组... 常州沟组是华北克拉通太古宙-古元古代变质基底上最早的沉积盖层之一,其碎屑锆石U-Pb年代学与Hf同位素特征分析对探讨长城系形成时代、源区特征以及基底演化均具有重要的研究意义。本文对华北克拉通中部赞皇杂岩瓮城地区长城系常州沟组底部砂岩样品进行了LA-ICP-MS碎屑锆石U-Pb定年和LA-MC-ICP-MS碎屑锆石Lu-Hf同位素分析。砂岩样品中碎屑锆石主要年龄峰值约为2 500 Ma,推断其碎屑物质主要来自于华北克拉通新太古代晚期变质基底,而最年轻的碎屑锆石年龄为1 822 Ma,结合赞皇杂岩变质基底普遍经历了1 850~1 800 Ma变质作用以及区域上上覆大红峪组火山岩中1 635 Ma结晶锆石年龄,限定瓮城地区长城系常州沟组沉积时代为1 800~1 635 Ma。砂岩样品中碎屑锆石的εHf(t)值变化于-6.8~+5.2之间,相应的两阶段模式年龄峰值约为2 820 Ma,结合赞皇杂岩已发表的2 900~2 700 Ma岩浆锆石和碎屑锆石Hf同位素结果,进一步表明2 900~2 700 Ma为赞皇杂岩地壳生长最主要的时期。综合太行山中南部地区已发表的长城系常州沟组的沉积学与新的年代学数据,推测赞皇杂岩瓮城地区长城系常州沟组沉积于陆内裂谷盆地。 展开更多
关键词 华北克拉通 赞皇杂岩 常州沟组 碎屑锆石 U-Pb-Hf同位素
下载PDF
基于复杂网络的中国与东盟航空运输联系研究
18
作者 曹允春 李嘉玉 《物流科技》 2024年第1期118-121,共4页
为探究我国同东盟航空运输联系发展水平,采用修正的引力模型对联系强度进行测算,基于测算结果构建中国与东盟城市航空运输联系空间网络,运用复杂网络方法对网络总体特征和节点中心性进行分析,发现我国与东盟航空联系强度较弱,整体呈上... 为探究我国同东盟航空运输联系发展水平,采用修正的引力模型对联系强度进行测算,基于测算结果构建中国与东盟城市航空运输联系空间网络,运用复杂网络方法对网络总体特征和节点中心性进行分析,发现我国与东盟航空联系强度较弱,整体呈上升趋势,联系的不均衡性较为明显;整体网络结构较为松散,呈现出“核心—边缘”的分布特点;度分布表现出多级分化现象,网络由少数核心城市主导,接近中心性总体分布均衡。 展开更多
关键词 复杂网络 航空运输联系 修正的引力模型 中国—东盟
下载PDF
冀北招兵沟铁磷矿床成矿时代及成因研究
19
作者 王亿 李立兴 +6 位作者 李厚民 李小赛 马兰晶 邢玉亮 孙欣宇 戴阳 王小慧 《现代地质》 CAS CSCD 北大核心 2024年第1期46-55,共10页
为探讨冀北—辽西地区太古宙变质岩系中铁磷矿床的成因问题,本研究选取招兵沟矿床开展了岩相学、年代学和地球化学研究。野外观察表明,前人描述的条带状铁磷矿石实际上大多为含铁磷矿脉的黑云角闪斜长片麻岩,可见铁磷矿脉切穿片麻理。... 为探讨冀北—辽西地区太古宙变质岩系中铁磷矿床的成因问题,本研究选取招兵沟矿床开展了岩相学、年代学和地球化学研究。野外观察表明,前人描述的条带状铁磷矿石实际上大多为含铁磷矿脉的黑云角闪斜长片麻岩,可见铁磷矿脉切穿片麻理。含铁磷黑云角闪斜长片麻岩中的锆石与矿石矿物铁钛氧化物和磷灰石密切共生。阴极发光图像上显示基性岩浆锆石特征,无/弱环带或斑块状结构,LA-ICP-MS U-Pb定年获得^(206)Pb/^(238)U加权平均年龄为(282±3)Ma(MSWD=0.78),指示铁磷矿化时代为早二叠世,而非传统认为的新太古代。招兵沟含铁磷黑云角闪斜长片麻岩与区域辉石-角闪石岩侵入体形成时代接近,微量元素地球化学特征相似度高,说明成矿母岩为辉石-角闪石岩。招兵沟铁磷成矿与冀北地区沿红石砬—大庙断裂带发育的显生宙阿拉斯加型镁铁-超镁铁质岩浆活动密切相关。综合来看,招兵沟铁磷矿床可能是与基性岩浆活动有关的矿床,而非传统认为的变质型矿床,其他相似矿床的成因也需要进一步研究。 展开更多
关键词 铁磷矿床 成矿年龄 矿床成因 阿拉斯加型岩体 华北克拉通
下载PDF
2001-2020年东海区大陆海岸带复合生态系统韧性时空演变
20
作者 张海涛 李加林 刘永超 《海洋通报》 CAS CSCD 北大核心 2024年第1期127-139,共13页
海岸带是自然、社会、经济相互作用频繁的地区,然而,过度开发胁迫海岸带生态环境退化。海岸带复合生态系统韧性研究有利于实现精准有效的生态保护。本文综合多源数据从复合生态系统基底状态、社会经济发展与资源环境禀赋的耦合协调关系... 海岸带是自然、社会、经济相互作用频繁的地区,然而,过度开发胁迫海岸带生态环境退化。海岸带复合生态系统韧性研究有利于实现精准有效的生态保护。本文综合多源数据从复合生态系统基底状态、社会经济发展与资源环境禀赋的耦合协调关系、复合生态系统的可持续发展潜力、人类活动对环境的影响范围与强度方面构建评价体系,定量评估2001-2020年东海区大陆海岸带复合生态系统韧性,分析韧性时空演变特征与空间分异的影响因素。结果表明:(1)2001-2020年东海区大陆海岸带复合生态系统韧性呈波动下降趋势,韧性空间异质性显著,具有明显的海陆梯度地带性。(2)林地是维持区域复合生态系统韧性的主体。(3)反映人类活动分布与强度的因素对复合生态系统韧性的影响越来越大。研究为保护、恢复、促进海岸带复合生态系统可持续利用与管理提供了理论支持与实践参考。 展开更多
关键词 复合生态系统 韧性 评价体系 东海海岸带
下载PDF
上一页 1 2 21 下一页 到第
使用帮助 返回顶部