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Studies on the Photosynthetic Characteristics andAssimilate's Accumulation and Transformation inHeavy Panicle Type of Rice 被引量:3
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作者 MAJun ZHUQing-sen +3 位作者 MAWen-bo TIANYan-hua YangJian-chang ZHOUKai-da 《Agricultural Sciences in China》 CAS CSCD 2003年第6期602-608,共7页
Using 18 indica rice varieties with different panicle weight, the photosynthetic characteristics and assimilate's accumulation and transformation in heavy panicle type of rice(HPT)were studied. The results showed ... Using 18 indica rice varieties with different panicle weight, the photosynthetic characteristics and assimilate's accumulation and transformation in heavy panicle type of rice(HPT)were studied. The results showed that the net photosynthetic rate of the flag leaf in HPT after heading was obviously higher than that in medium panicle type(MPT)and light panicle type(LPT). The reason for the high net photosynthetic rate in HPT was the increase of Rubisco activities and chlorophyll content, and keeping high assimilate ability to CO2 under high and low light intensity, high temperature and low CO2 content, and light midday depression and wide adaptability to environmental conditions. The high net photosynthetic rate of HPT might be also the results of its excellent stomatal characteristics and higher total quantity of stomatal opening degrees(stomatal density X stomatal opening degrees). There was a large amount of dry matter production after heading and obvious high assimilate's transformation to panicle in HPT. 展开更多
关键词 RICE Heavy panicle type Photosynthetic characteristics Assimilate's accumulation Assimilate's transformation High yield breeding
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THE FRACTIONAL TYPE MARCINKIEWICZ INTEGRALS AND COMMUTATORS ON WEIGHTED HARDY SPACES
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作者 韩妍妍 伍火熊 《Acta Mathematica Scientia》 SCIE CSCD 2023年第5期1981-1996,共16页
This paper is devoted to studying the behaviors of the fractional type Marcinkiewicz integralsμΩ,βand the commutatorsμΩ,βb generated byμΩ,βwith b b∈Lloc(Rn)on weighted Hardy spaces.Under the assumption of th... This paper is devoted to studying the behaviors of the fractional type Marcinkiewicz integralsμΩ,βand the commutatorsμΩ,βb generated byμΩ,βwith b b∈Lloc(Rn)on weighted Hardy spaces.Under the assumption of that the homogeneous kernelΩsatisfies certain regularities,the authors obtain the boundedness ofμΩ,βfrom the weighted Hardy spaces Hωpp(Rn)to the weighted Lebesgue spaces Lωqq(Rn)for n/(n+β)≤<p≤1 with 1/q=1/p-β/n,as well as the same(Hωpp,Lωqq)-boudedness ofμΩ,βb when b belongs to BMOωp,p(Rn),which is a non-trivial subspace of BMO(Rn). 展开更多
关键词 fractional type Marcinkiewicz integrals COMMUTATORS Muckenhoupt weights BMO spaces Hardy spaces
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Anti-Fowler Temperature Regime in Photoemission from <i>n</i>-Type Semiconductors with Surface Accumulation Layer
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作者 Michel Molotskii Klimentiy Shimanovich Yossi Rosenwaks 《Journal of Modern Physics》 2017年第7期1020-1028,共9页
According to the Fowler theory and numerous experiments the quantum efficiency for photoemission from conductors increases with temperature. Here we show that an opposite temperature dependence is also possible, when ... According to the Fowler theory and numerous experiments the quantum efficiency for photoemission from conductors increases with temperature. Here we show that an opposite temperature dependence is also possible, when the photoemission is from quasi-metallic surface accumulation layers of n-type semiconductors. This is due to the temperature dependence of the Fermi level energy in semiconductors. The Fermi level energy increases with decreasing temperature;this leads to a decrease of the semiconductor work function and consequently an increase of the quantum efficiency photoemission at constant value of absorbed light quanta of energy. We have calculated this effect for electron accumulation layer in n-GaN, induced by adsorption of positively charged cesium or barium ions. It is found that at low temperatures near liquid nitrogen, the quantum efficiency for photoemission increases to near 55%, which is comparable to the largest values, reported for any known photo-ca-thodes. This phenomenon may prove useful for efficient photo-cathodes operating at low temperatures. 展开更多
关键词 PHOTOEMISSION PHOTOCATHODE Electronic accumulation Layer N-type Semiconductor
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Tight sandstone gas accumulation mechanism and development models 被引量:12
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作者 Zhen-Xue Jiang Zhuo Li +4 位作者 Feng Li Xiong-Qi Pang Wei Yang Luo-Fu Liu Fu-Jie Jiang 《Petroleum Science》 SCIE CAS CSCD 2015年第4期587-605,共19页
Tight sandstone gas serves as an important unconventional hydrocarbon resource, and outstanding results have been obtained through its discovery both in China and abroad given its great resource potential. However, he... Tight sandstone gas serves as an important unconventional hydrocarbon resource, and outstanding results have been obtained through its discovery both in China and abroad given its great resource potential. However, heated debates and gaps still remain regarding classification standards of tight sandstone gas, and critical controlling factors, accumulation mechanisms, and devel- opment modes of tight sandstone reservoirs are not deter- mined. Tight sandstone gas reservoirs in China are generally characterized by tight strata, widespread distri- bution areas, coal strata supplying gas, complex gas-water relations, and abnormally low gas reservoir pressure. Water and gas reversal patterns have been detected via glass tube and quartz sand modeling, and the presence of critical geological conditions without buoyancy-driven mecha- nisms can thus be assumed. According to the timing of gas charging and reservoir tightening phases, the following three tight sandstone gas reservoir types have been identified: (a) "accumulation-densification" (AD), or the conventional tight type, (b) "densification-accumulation" (DA), or the deep tight type, and (c) the composite tight type. For the AD type, gas charging occurs prior to reser- voir densification, accumulating in higher positions under buoyancy-controlled mechanisms with critical controlling factors such as source kitchens (S), regional overlaying cap rocks (C), gas reservoirs, (D) and low fluid potential areas (P). For the DA type, reservoir densification prior to the gas charging period (GCP) leads to accumulation in depres- sions and slopes largely due to hydrocarbon expansive forces without buoyancy, and critical controlling factors are effective source rocks (S), widely distributed reservoirs (D), stable tectonic settings (W) and universal densification of reservoirs (L). The composite type includes features of the AD type and DA type, and before and after reservoir densification period (RDP), gas charging and accumulation is controlled by early buoyancy and later molecular expansive force respectively. It is widely distributed in anticlinal zones, deep sag areas and slopes, and is con- trolled by source kitchens (S), reservoirs (D), cap rocks (C), stable tectonic settings (W), low fluid potential areas (P), and universal reservoir densification (L). Tight gas resources with great resource potential are widely dis- tributed worldwide, and tight gas in China that presents advantageous reservoir-forming conditions is primarily found in the Ordos, Sichuan, Tarim, Junggar, and Turpan- Hami basins of central-western China. Tight gas has served as the primary impetus for global unconventional natural gas exploration and production under existing technical conditions. 展开更多
关键词 Tight sandstone gas Reservoir features accumulation mechanism type classification Development mode
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KKM TYPE THEOREMS AND COINCIDENCE THEOREMS ON L-CONVEX SPACES 被引量:13
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期419-426,共8页
Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixe... Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixed point theorems are obtained in L-convex spaces. These theorems improve and generalize many important known results in recent literature. 展开更多
关键词 KKM type theorem coincidence theorem L-convex space
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Dynamic Systems of Petroleum Accumulation in the Nanpu Depression,Bohai Bay Basin,China 被引量:3
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作者 LIU Guangdi SUN Mingliang +1 位作者 ZHANG Zhihuan DONG Yuexia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2010年第5期1273-1285,共13页
It is significant to distinguish the dynamic systems of petroleum accumulation (DSPA) for the understanding of petroleum accumulation and distribution. According to the formation pressure framework, genetic types of... It is significant to distinguish the dynamic systems of petroleum accumulation (DSPA) for the understanding of petroleum accumulation and distribution. According to the formation pressure framework, genetic types of petroleum and characteristics of conduit systems, three dynamic systems of petroleum accumulation were identified in the vertical profile in the Nanpu depression, Bohai Bay basin. The deeper DSPA (including formations Es3 to Es2) is a sealed system with high-overpressure and high-mature self-sourced oil. Most of the crude oil in the system accumulated in the periods of late Oligocene (23.5 Ma) and late Pliocene (2.4 Ma). The middle DSPA (including formations Es~ to Edl) is an overpressured half-sealed system with mature or lower-mature self-sourced oil. The accumulation of oil in the system also occurred in the late Oligocene (23.5 Ma) and late Pliocene (2.4 Ma). The shallower DSPA (including formations Ed2 to Q) is a hydrostatic system with lower-mature aliensourced oil from the middle system. Oil within this system accumulated only in the late Pliocene period. The oil in the shallower system migrated vertically along the faults from the formerly accumulated oil in the middle system by lateral migration along the sandbodies, whereas petroleum accumulation in the deeper system was mainly derived from the system itself by lateral migration along the sandbodies and rarely migrated out of the system. In this case, it seems that the deeper system is a more potential exploration prospect in addition to the other two proved favorable systems. 展开更多
关键词 dynamic system of petroleum accumulation genetic types of petroleum pressureframework accumulation process Nanpu depression
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TOEPLITZ-TYPE OPERATORS ON LEBESGUE SPACES 被引量:7
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作者 陆善镇 默会霞 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期140-150,共11页
Let L be the infinitesimal generator of an analytic semigroup on L 2 (Rn)with Gaussian kernel bounds,and L-α/ 2 be the fractional integrals generated by L for 0< α<n.Let Tj,1 be the singular integral with nons... Let L be the infinitesimal generator of an analytic semigroup on L 2 (Rn)with Gaussian kernel bounds,and L-α/ 2 be the fractional integrals generated by L for 0< α<n.Let Tj,1 be the singular integral with nonsmooth kernel related to L,or Tj,1=I, Tj,2,Tj,4 be the linear operators,which are bounded on Lp(Rn)for 1<p<∞,and Tj,3=±I(j=1,2,···,m),where I is the identity operator.For b∈L 1 loc (Rn),denote the Toeplitz-type operator byΘαbfmj=1(Tj,1MbIαTj,2 + Tj,3MbIαTj,4),where Mb is a multiplication ope... 展开更多
关键词 Toeplitz type operator generalized fractional integral singular integral with nonsmooth kernel Lipschitz function space
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COMPOSITION OPERATORS BETWEEN BLOCH TYPE SPACES IN THE UNIT BALL 被引量:3
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作者 戴济能 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 2014年第1期73-81,共9页
In this paper, we obtain some new necessary and sufficient conditions for the boundedness and compactness of composition operators Cφ between Bloch type spaces in the unit ball Bn.
关键词 composition operator Bloch type space BOUNDEDNESS COMPACTNESS
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Mechanism and effects of snow accumulations and controls by lightweight snow fences 被引量:3
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作者 Duote Liu Yongle Li +2 位作者 Bin Wang Peng Hu Jingyu Zhang 《Journal of Modern Transportation》 2016年第4期261-269,共9页
This paper investigates the snowdrifts caused by lightweight fences along the lines on the flatland through the computational fluid dynamics method. The characteristic ambient flows around the solid fences and the por... This paper investigates the snowdrifts caused by lightweight fences along the lines on the flatland through the computational fluid dynamics method. The characteristic ambient flows around the solid fences and the porous fences with varied heights and bottom wind gaps are simulated in the numerical model, and the working mechanism of "interception" and "scouring" of the lightweight fences are analyzed. Based on the friction velocities near the ground, two sets of criteria are proposed to evaluate the deposition and erosion effects of different fences. According to flow separation and reattachment, the simplified relationships between the most likely positions for snow accumulations and fence parameters are devel- oped. The study indicates that the capabilities for snow interception by the solid fence without wind gap and the distance from which to the second snow coverage center both increase with the fence height. Furthermore, it is found that the scouring range for snow surface increases significantly with the size of wind gap, and the snow accumulation rate on the leeward side decreases with the increasing fence porosity. 展开更多
关键词 Lightweight fence Snowdrift. CFD Mechanism of snow accumulation Fence type Fenceparameter
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COMPOSITION TYPE OPERATORS FROM HARDY SPACES TO μ-BLOCH SPACES ON THE UNIT BALL 被引量:2
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作者 王雄亮 刘太顺 《Acta Mathematica Scientia》 SCIE CSCD 2009年第5期1430-1438,共9页
Let φ be a holomorphic self-map of Bn and ψ ∈ H(Hn). A composition type operator is defined by Tψ,φ(f) = ψf o φ for f ∈ H(Bn), which is a generalization of the multiplication operator and the composition... Let φ be a holomorphic self-map of Bn and ψ ∈ H(Hn). A composition type operator is defined by Tψ,φ(f) = ψf o φ for f ∈ H(Bn), which is a generalization of the multiplication operator and the composition operator. In this article, the necessary and sufficient conditions are given for the composition type operator Tψ,φ to be bounded or compact from Hardy space HP(Bn) to μ-Bloch space Bμ(Bn). The conditions are some supremums concerned with ψ,φ, their derivatives and Bergman metric of Bn. At the same time, two corollaries are obtained. 展开更多
关键词 Hardy spaces μ-Bloch spaces composition type operators BOUNDEDNESS COMPACTNESS
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Some New Theorems of Lipschitz Type Mappings in Cone Metric Spaces 被引量:5
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作者 HAN Yan XU Wang-bin XU Shao-yuan 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第2期224-233,共10页
In this paper, some new existence and uniqueness of common fixed points for three mappings of Lipschitz type are obtained. The conditions are greatly weaker than the classic conditions in cone metric spaces. These res... In this paper, some new existence and uniqueness of common fixed points for three mappings of Lipschitz type are obtained. The conditions are greatly weaker than the classic conditions in cone metric spaces. These results improve and generalize several wellknown comparable results in the literature. Moreover, our results are supported by some examples. 展开更多
关键词 cone metric space lipschitz type mapping common fixed point
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FIXED POINT RESULTS ON METRIC-TYPE SPACES 被引量:1
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作者 Monica COSENTINO Peyman SALIMI Pasquale VETRO 《Acta Mathematica Scientia》 SCIE CSCD 2014年第4期1237-1253,共17页
In this paper we obtain fixed point and common fixed point theorems for self- mappings defined on a metric-type space, an ordered metric-type space or a normal cone metric space. Moreover, some examples and an applica... In this paper we obtain fixed point and common fixed point theorems for self- mappings defined on a metric-type space, an ordered metric-type space or a normal cone metric space. Moreover, some examples and an application to integral equations are given to illustrate the usability of the obtained results. 展开更多
关键词 metric-type space fixed point common fixed point Suzuki type mappings cone metric space integral equation
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A MAXIMAL FUNCTION CHARACTERIZATION 0F HARDY SPACES ON SPACES OF HOMOGENEOUS TYPE 被引量:5
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作者 Li Wenming Zhongshan University, China 《Analysis in Theory and Applications》 1998年第2期12-27,共16页
A new maximal function is introduced in the dual spaces of test function spaces on spaces of homogeneous type. Using this maximal function, we get new characterization of atomic H^p spaces.
关键词 A MAXIMAL FUNCTION CHARACTERIZATION 0F HARDY spaceS ON spaceS OF HOMOGENEOUS type APPI 尸气
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Boundedness for Hardy Type Operators on Herz Spaces with Variable Exponents 被引量:1
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作者 Min Wang Lisheng Shu Meng Qu 《Analysis in Theory and Applications》 2014年第2期224-235,共12页
In this paper, we will prove the boundedness of Hardy type operators Hβ(x) and Hβ^*(x) of variable order β(x) on Herz spaces Kp(·)^α(·)q and Kp(·)^α(·)q′,where α(·) an... In this paper, we will prove the boundedness of Hardy type operators Hβ(x) and Hβ^*(x) of variable order β(x) on Herz spaces Kp(·)^α(·)q and Kp(·)^α(·)q′,where α(·) and p(·)are both variable. 展开更多
关键词 Herz spaces Hardy type operators variable exponent.
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ON DIRICHLET TYPE SPACES AND α-BLOCH SPACES IN THE UNIT BALL OF C^n 被引量:1
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作者 李波 欧阳才衡 《Acta Mathematica Scientia》 SCIE CSCD 2004年第4期645-654,共10页
In this paper, the authors study the inclusion relations between Dirichlet type spaces DΥT and α-Bloch spaces βα by means of higher radial derivative. The strictness and the best possibility of the inclusion relat... In this paper, the authors study the inclusion relations between Dirichlet type spaces DΥT and α-Bloch spaces βα by means of higher radial derivative. The strictness and the best possibility of the inclusion relations are shown with constructive methods. Furthermore, they sharpen one of the results when Υ=n, which proves that a conjecture in [7] is true. 展开更多
关键词 Dirichlet type spaces α-Bloch spaces inclusion relations
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Toeplitz Type Operator Associated to Singular Integral Operator with Variable Kernel on Weighted Morrey Spaces 被引量:1
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作者 Yuexiang He Yueshan Wang 《Analysis in Theory and Applications》 CSCD 2016年第1期90-102,共13页
Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I (the identity operator). Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this pa... Suppose T^k,l and T^k,2 are singular integrals with variable kernels and mixed homogeneity or ±I (the identity operator). Denote the Toeplitz type operator by T^b=k=1∑^QT^k,1M^bT^k,2 where M^bf= bf. In this paper, the boundedness of Tb on weighted Morrey space are obtained when b belongs to the weighted Lipschitz function space and weighted BMO function space, respectively. 展开更多
关键词 Toeplitz type operator singular integral operator variable Calderon-Zygmund kernel weighted BMO function weighted Lipschitz function weighted Morrey space.
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INTERPOLATION SPACES BETWEEN H^1 AND L~∞ ON SPACES OF HOMOGENEOUS TYPE 被引量:2
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作者 Li Wenming (Hebei Normal University, China) 《Approximation Theory and Its Applications》 2002年第3期86-92,共7页
Using the maximal function characterization of Hardy spaces, we study the interpolation spaces between H1 and L∞ on spaces of homogeneous type.
关键词 MATH ON spaceS OF HOMOGENEOUS type INTERPOLATION spaceS BETWEEN H~1 AND L
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CALDER6N-ZYGMUND OPERAORS ON THE HARDY SPACES OF WEIGHTED HERZ TYPE 被引量:2
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作者 Liu Weiquan and Lu Shanzhen(Beijing Normal University, China) 《Analysis in Theory and Applications》 1997年第2期1-10,共10页
Applying the decomposition theorems in [1] and [2] , we obtain the boundedness theorem of Calderbn-Zygmund operator of type 6 on the Hardy spaces of weighted Herz type and establish interpolation theorem of linear ope... Applying the decomposition theorems in [1] and [2] , we obtain the boundedness theorem of Calderbn-Zygmund operator of type 6 on the Hardy spaces of weighted Herz type and establish interpolation theorem of linear operators on the weighted Herz spaces. - 展开更多
关键词 II CALDER6N-ZYGMUND OPERAORS ON THE HARDY spaceS OF WEIGHTED HERZ type MATH
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EMBEDDING THEOREMS ON CAMPANATO-MORREY SPACES FOR VECTOR FIELDS OF HoRMANDER TYPE 被引量:3
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作者 Guozhen Lu (Wright State University, USA) 《Analysis in Theory and Applications》 1998年第1期69-80,共12页
This paper deals with embedding theorems on Campanato-Marrey spaces formed by degenerate vector fields, which include Honnander and Grushin type of vector fields. These embedding theorems are somewhat different from t... This paper deals with embedding theorems on Campanato-Marrey spaces formed by degenerate vector fields, which include Honnander and Grushin type of vector fields. These embedding theorems are somewhat different from the known Poincare estimates. The main ingredients of the proofs rely on the fractional maximal functions. These results evidently have applications to the regularity of subelliptic PDE. 展开更多
关键词 EMBEDDING THEOREMS ON CAMPANATO-MORREY spaceS FOR VECTOR FIELDS OF HoRMANDER type MATH
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Accumulation and exploration of petroleum reservoirs in west slope of northern Songliao Basin, China 被引量:1
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作者 MENG Qi’an BAI Xuefeng +3 位作者 ZHANG Wenjing FU Li XUE Tao BAO Li 《Petroleum Exploration and Development》 2020年第2期254-265,共12页
On the basis of the present situation of oil and gas exploration and geological research of the west slope in the northern Songliao Basin, the factors controlling reservoir formation, oil and gas migration and accumul... On the basis of the present situation of oil and gas exploration and geological research of the west slope in the northern Songliao Basin, the factors controlling reservoir formation, oil and gas migration and accumulation, have been re-examined from the aspects of structure, deposition and reservoir formation. The results show that:(1) The west slope is a gentle slope which overlaps to the west, and nose structure is developed near the hydrocarbon generation depression, which is in the dominant direction area of hydrocarbon migration. A series of NE structural belts are developed on the slope and are favorable places for oil and gas accumulation.(2) The west slope can be further divided into the upper slope and the lower slope, and there are many kinds of oil and gas reservoirs, including structural, structural-lithologic and lithologic ones. In the upper slope, the major oil layer is Sartu controlled by structure;in the lower slope, multi-layers are oil-bearing, and the oil reservoirs are mostly composite ones.(3) Faults, unconformity surfaces and continuous sand bodies are the main channels of oil and gas migration;structure, sand body and fault jointly control the oil and gas enrichment in the slope;and the matching relationship between micro-amplitude and sand body, small fault and sand body control the oil and gas accumulation. On the basis of the above research, fine identification and effectiveness evaluation technology of composite trap has been developed through extensive study. Combination traps were identified by multiple technologies, including fault classification, micro-amplitude structure identification, fine sedimentation research, and lithologic trap identification by waveform indication inversion;and then the configuration relationship between fault and sand body, structural amplitude and sand body were analyzed to set up the evaluation criteria of effective traps. According to the criteria, the traps were selected to enhance the exploration success rate. 展开更多
关键词 reservoir type accumulation features exploration practice slope accumulation west slope Songliao Basin
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