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Studying Some Physicochemical Characteristics of Crust Coated with White Egg and Chitosan Using a Deep-Fried Model System 被引量:3
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作者 Elham Ansarifar Mohebbat Mohebbi Fakhri Shahid 《Food and Nutrition Sciences》 2012年第5期685-692,共8页
In this paper, the effects of frying time, white egg (0%, 5% and 10% w/w) and chitosan (0%, 0.5% and 1.5% w/w) addition to the batter formulation on the quality of simulated crispy deep-fried Kurdish cheese nugget cru... In this paper, the effects of frying time, white egg (0%, 5% and 10% w/w) and chitosan (0%, 0.5% and 1.5% w/w) addition to the batter formulation on the quality of simulated crispy deep-fried Kurdish cheese nugget crusts was studied by using a deep-fried crust model. Moisture content, oil content, color and hardness of the samples were determined. Crust models were fried at 190℃ for 60, 120 and 180 s. Batter formulations and frying time significantly (p < 0.01) affected moisture, oil content, color and hardness of Crust models. Batter formulation contain 10% white egg was found to be an effective ingredient in decreasing oil content of Crust models. The mean moisture and fat content of Crust models formed with batter contained 10% white egg, fried at 190℃, for 180s were 6.207 ± 0.447 and 5.649 ± 0.394. Batters containing 5% white egg and 1.5% chitosan showed the lowest moisture content and the highest oil content among all the formulations. Crust models containing combination of white egg and chitosan were the darkest. Hardness of samples containing chitosan were the highest, specially for ch1.5 The mean hardness in 60, 120 and 180s of frying in this formulation were 21.518 ± 0.481, 36.871 ± 1.758 and 49.563 ± 1.847 respectively. 展开更多
关键词 FRYING deep-fried crust model System CHITOSAN WHITE EGG
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The Identification and Modeling of the Volcanic Weathering Crust in the Yingcheng Formation of the Xujiaweizi Fault Depression, Songliao Basin 被引量:5
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作者 LIU Cai CHI Huanzhao +1 位作者 SHAN Xuanlong HAO Guoli 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第4期1339-1351,共13页
Through the analysis of core descriptions, well-logs, seismic data, geochemical data and structural settings of the volcanic rock of the Yingcheng Formation in the Xujiaweizi fault depression, Songliao Basin, and the ... Through the analysis of core descriptions, well-logs, seismic data, geochemical data and structural settings of the volcanic rock of the Yingcheng Formation in the Xujiaweizi fault depression, Songliao Basin, and the geological section of the Yingcheng Formation in the southeast uplift area, this work determined the existence of volcanic weathering crust exists in the study area. The identification marks on the volcanic weathering crust can be recognized on the scale of core, logging, seismic, geochemistry, etc. In the study area, the structure of this crust is divided into clay layer, leached zone, fracture zone and host rocks, which are 5-118 m thick (averaging 27.5 m). The lithology of the weathering crust includes basalt, andesite, rhyolite and volcanic breccia, and the lithofacies are igneous effusive and extrusive facies. The volcanic weathering crusts are clustered together in the Dashen zone and the middle of the Xuzhong zone, whereas in the Shengshen zone and other parts of the Xuzhong zone, they have a relatively scattered distribution. It is a major volcanic reservoir bed, which covers an area of 2104.16 km2. According to the geotectonic setting of the Songliao Basin, the formation process of the weathering crust is complete. Combining the macroscopic and microscopic features of the weathering crust of the Yingcheng Formation in Xujiaweizi with the logging and three-dimensional seismic sections, we established a developmental model of the paleo uplift and a developmental model of the slope belt that coexists with the sag on the Xujiaweizi volcanic weathering crust. In addition, the relationship between the volcanic weathering crust and the formation and distribution of the oil/gas reservoir is discussed. 展开更多
关键词 Xujiaweizi fault depression Yingcheng Formation identification marks volcanic weathering crust developmental model
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Five-Stage Model of the Palaeozoic Crustal Evolution in Xinjiang 被引量:1
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作者 LIU Dequan TANG Yanling ZHOU Ruhong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1998年第4期339-349,共11页
Abstract: The great majority of the Palaeozoic orogenic belts of Central Asia are of the intercontinental type, whose evolution always follows a five-stage model, i.e. the basal continental crust-extensional transitio... Abstract: The great majority of the Palaeozoic orogenic belts of Central Asia are of the intercontinental type, whose evolution always follows a five-stage model, i.e. the basal continental crust-extensional transitional crust-oceanic crust-convergent transitional crust-new continental crust model. The stage for the extensional transitional crust is a pretty long, independent and inevitable phase. The dismembering mechanism of the basal continental crust becoming an extensional continental crust is delineated by the simple shear model put forward by Wernike (1981). The continental margins on the sides of a gently dipping detachment zone and moving along it are asymmetric: one side is of the nonmagmatic type and the other of the magmatic type with a typical bimodal volcanic formation. In the latter case, however, they were often confused with island arcs. This paper discusses the five-stage process of the crustal evolution of some typical orogenic belts in Xinjiang. 展开更多
关键词 crustal evolution extensional transitional crust oceanic crust new continental crust five-stage model XINJIANG
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Finite element modeling of convective pore-fluid flow in fluid-saturated porous rocks within upper crust:An overview 被引量:3
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作者 ZHAO Chong-bin Bruce HOBBS Alison ORD 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第3期501-514,共14页
Convective pore-fluid flow (CPFF) plays a critical role in generating mineral deposits and oil reservoirs within the deep Earth. Therefore, theoretical understanding and numerical modeling of the thermodynamic process... Convective pore-fluid flow (CPFF) plays a critical role in generating mineral deposits and oil reservoirs within the deep Earth. Therefore, theoretical understanding and numerical modeling of the thermodynamic process that triggers and controls the CPFF are extremely important for the exploration of new mineral deposits and underground oil resources. From the viewpoint of science, the CPFF within the upper crust can be treated as a kind of thermodynamic instability problem of pore-fluid in fluid-saturated porous media. The key issue of dealing with this kind of problem is to assess whether a nonlinear thermodynamic system under consideration is supercritical. To overcome limitations of using theoretical analysis and experimental methods in dealing with the CPFF problems within the upper crust, finite element modeling has been broadly employed for solving this kind of problem over the past two decades. The main purpose of this paper is to overview recent developments and applications of finite element modeling associated with solving the CPFF problems in large length-scale geological systems of complicated geometries and complex material distributions. In particular, two kinds of commonly-used finite element modeling approaches, namely the steady-state and transient-state approaches, and their advantages/disadvantages are thoroughly presented and discussed. 展开更多
关键词 convective flow steady-state approach transient-state approach numerical modeling upper crust porous rock
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A multi-scale 3-D crust velocity model in the Hefei-Chao Lake area around the southern segment of Tanlu Fault Zone 被引量:1
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作者 Lingli Li Huajian Yao +4 位作者 Song Luo Junhui Li Xiaoli Wang Hongyu Ni Ziwen Bao 《Earthquake Science》 2021年第4期344-357,共14页
Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the ... Regional high-precision velocity models of the crust are an important foundation for examining seismic activity,seismogenic environments,and disaster distribution characteristics.The Hefei-Chao Lake area contains the main geological units of Hefei Basin,with thick sediments and the Chao Lake depression.Several major concealed faults of the southern NNE-trending Tanlu Fault Zone cross this area.To further explore the underground distribution characteristics of the faults and their tectonic evolutionary relationship with adjacent tectonic units,this study used ambient noise data recorded by a seismic array deployed in Hefei City and Chao Lake,constructing a 3-D velocity model at the depth of 1–8 km.Then a multi-scale high-resolution 3-D velocity model of this area was constructed by this new upper crustal velocity model with the previous middle and lower crustal model.The new model reveals that a high-velocity belt is highly consistent with the strike of the Tanlu Fault Zone,and a low-velocity sedimentary characteristic is consistent with the Hefei Basin and Chao Lake depression.The distribution morphology of high and low velocity bodies shows that the sedimentary pattern of Hefei-Chao Lake area is closely related to the tectonic evolution of the Tanlu Fault Zone since the Mesozoic.This study also identifies multiple low-velocity anomalies in the southeastern Hefei City.We speculate that strong ground motion during the 2009 Feidong earthquake(magnitude of 3.5)was related to amplification by the thick sediments in the Hefei Basin.We also discuss further applications of multi-scale high-resolution models of the shallow layer to strong ground motion simulations in cities and for earthquake disaster assessments. 展开更多
关键词 Tanlu Fault Zone Hefei-Chao Lake area crust multi-scale velocity model
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Gravity Modeling for the Rifted Crust at the Arabian Shield Margin – Further Insight into Red Sea Spreading
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作者 Saad Mogren Manoj Mukhopadhyay 《Open Journal of Geology》 2013年第2期28-33,共6页
A large variation in elevation and gravity anomaly prevails from the Red Sea coast to the interior of the Arabian Shield (AS) across the Asir Igneous Province (AIP);The Asir Mountain (AM) is developed on AIP. Here the... A large variation in elevation and gravity anomaly prevails from the Red Sea coast to the interior of the Arabian Shield (AS) across the Asir Igneous Province (AIP);The Asir Mountain (AM) is developed on AIP. Here the elevation varies from 45 - 2700 m, corresponding changes in F.A. are from –30 to + 220 mgal and B.A. from +22 to –175 mgal. Regression relationships between elevation and gravity anomalies demonstrate significant changes in trend at about 400 m threshold of elevation across the pediment west of AM, at about 45 km inland of the shoreline, flanking the Hizaz-Asir Escarpment (HAE). Gravity anomaly variation along a traverse taken across HAE and AIP is interpreted here in terms of anomalous masses in crust as well as due to deeper crustal configuration. 2D gravity interpretation is, in part, constrained by surface geology, available geologic cross-sections for crust, interpretations from the IRIS Deep-Seismic Refraction Line, and to a lesser extent by the available gross results from shear-wave splitting and receiver function analysis. The gravity model provides probable solutions for the first time on geometric configuration and geophysical identification: a) for the seaward margin of the mid-Tertiary Mafic Crust (TMC) below sediment cover of the Asir pediment that coincides with the 400 m threshold elevation. This signifies an anomalous uplift at the rifting phase. Moho below TMC extends from 10 - 22 km depth across HAE and west margin of AIP, b). Thinned continental crust below the Asir margin whose upper layer coincides with a seismic reflector is at about 22 km depth, c). Rift-margin characteristic detachment fault associated with basaltic flows on top surface of TMC at its inner margin, d). Two geologically mapped low-angle normal faults dipping to the east developed between the basic rocks intruding the AIP and e). felsic pluton farther east within AS. Large scale igneous activity followed by intense deformation affecting AIP clearly owes their origin to the rifting architecture of the AS at the Red Sea extensional margin. 展开更多
关键词 Shield-margin MAFIC crust Asir IGNEOUS Province Seismic MOHO 2D Gravity crustAL model Red Sea Ex-tensional MARGIN
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风化壳淋积型稀土矿浸取过程的模拟计算研究Ⅳ:考虑净吸附的液-固萃取模型 被引量:1
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作者 程福祥 吴声 +2 位作者 廖春生 孙聆东 严纯华 《中国稀土学报》 北大核心 2025年第4期772-787,共16页
风化壳淋积型稀土矿山粘土中常具有对浸矿剂离子或稀土离子的净吸附能力。假定净吸附形式为对浸矿剂NH_(4)^(+)的物理吸附和专性吸附以及对RE^(3+)的离子交换吸附,建立了考虑净吸附的风化壳淋积型稀土矿液-固萃取浸取模型,并计算讨论了... 风化壳淋积型稀土矿山粘土中常具有对浸矿剂离子或稀土离子的净吸附能力。假定净吸附形式为对浸矿剂NH_(4)^(+)的物理吸附和专性吸附以及对RE^(3+)的离子交换吸附,建立了考虑净吸附的风化壳淋积型稀土矿液-固萃取浸取模型,并计算讨论了不同净吸附类型对于稀土浸取过程和浸取效果的影响。结果显示,矿土中存在对NH_(4)^(+)的物理吸附和专性吸附均可导致浸出液中稀土峰值浓度降低;矿土对NH_(4)^(+)的净吸附能力增加还将导致浸矿剂消耗增加。通常半风化矿可净吸附离子相稀土,对于相同稀土品位的半风化原矿,净吸附RE^(3+)能力越强,母液中稀土穿透越为滞后,稀土穿透曲线拖尾现象也越严重,同时因净吸附稀土的矿土相当于提升了稀土品位而使硫酸铵投入/稀土产出比增大;半风化层中存在的稀土净吸附位点因可吸附前锋浸矿液中的RE^(3+)离子,理论上与已吸附了RE^(3+)离子的位点等效消耗浸矿剂。 展开更多
关键词 风化壳淋积型稀土矿 柱浸 液-固萃取模型 离子交换机理 净吸附
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基于剪切波分裂的地球内部各向异性研究综述
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作者 刘剑 王睿敏 李丽 《大地测量与地球动力学》 北大核心 2025年第5期532-544,共13页
地球内部圈层存在各向异性,且各向异性成因机制不同。剪切波分裂可揭示不同构造、不同深度各向异性介质特征,为地球深部动力学演化研究和地震预测提供重要信息。本文介绍地球内部各向异性成因机制,总结剪切波分裂方法发展情况,以及利用... 地球内部圈层存在各向异性,且各向异性成因机制不同。剪切波分裂可揭示不同构造、不同深度各向异性介质特征,为地球深部动力学演化研究和地震预测提供重要信息。本文介绍地球内部各向异性成因机制,总结剪切波分裂方法发展情况,以及利用剪切波分裂方法研究地壳和地幔介质各向异性的成果与进展,并在此基础上综合分析壳幔耦合模式。 展开更多
关键词 剪切波分裂 各向异性介质 地壳 地幔 壳幔耦合模式
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南海西南次海盆陆缘演化与幕式扩张的岩浆-构造-地层记录 被引量:1
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作者 杨天一 唐勇 +1 位作者 任建业 巢鹏 《地球科学》 北大核心 2025年第1期195-216,共22页
目前对于边缘海背景下被动大陆边缘的形成演化机制仍存在争议,特别是对洋陆转换带的构造特征与形成过程的认识存在明显不足.为了深入探索边缘海背景下南海陆缘与洋陆转换带构造结构与形成演化特征,通过对横跨西南次海盆V型尖端地震剖面... 目前对于边缘海背景下被动大陆边缘的形成演化机制仍存在争议,特别是对洋陆转换带的构造特征与形成过程的认识存在明显不足.为了深入探索边缘海背景下南海陆缘与洋陆转换带构造结构与形成演化特征,通过对横跨西南次海盆V型尖端地震剖面的解释与研究,识别出莫霍面(Moho)、基底和海底3个一级陆缘界面,划分出细颈化域、超伸展域、原洋域等构造单元;进一步精细解释了共轭陆缘盆地充填层序和多期断裂系统,识别出破裂不整合界面Bi,将陆缘盆地同裂陷期层序(Tg-Bi)划分为S1-S5五个层序,建立了西南次海盆V型尖端区域共轭陆缘的构造-地层格架.构造-地层格架中S3/S4层序之间的界面CBi、S4/S5之间的界面POBi分别与陆壳破裂和原洋洋壳Ⅰ的破裂对应,记录了西南次海盆共轭陆缘岩石圈伸展破裂过程中发生的重要构造事件.结合断裂活动性和盆地原型的分析,将西南次海盆共轭陆缘同裂陷期的演化划分为伸展、细颈化、超伸展和原洋洋壳四个阶段,建立了西南次海盆共轭陆缘演化模式.还建立了西南次海盆V型尖端共轭陆缘地壳的“鳄鱼嘴”结构,识别出总宽度达231 km的两期原洋洋壳.结合外缘高地和同破裂层序(S4-S5)研究,提出两期原洋洋壳的发育与西南次海盆的两幕扩张过程相对应,由原洋洋壳构成了同期洋盆的洋陆转换带.揭示了西南次海盆张开过程中岩石圈的伸展破裂机制与洋脊传播过程中幕式扩张作用对陆缘构造、地层和岩浆作用的影响,对于深入研究南海岩石圈的伸展破裂过程、洋陆转换带的成因以及南海被动陆缘形成的动力学机制具有重要意义. 展开更多
关键词 南海 西南次海盆 陆缘演化模式 幕式扩张 原洋洋壳 洋陆转换带 岩浆-构造-地层记录 海洋地质学
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彬长地区下古生界风化壳岩溶储层特征及分布
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作者 刘玲 冷佳宣 +2 位作者 张军涛 杨飞 袁春燕 《西南石油大学学报(自然科学版)》 北大核心 2025年第4期51-61,共11页
鄂尔多斯盆地彬长地区下古生界风化壳岩溶储层勘探前景良好,是实现油气突破和未来增储上产的重要阵地。但该区勘探程度低,风化壳岩溶储层尚未进行系统研究,储层发育特征及分布规律认识不清,严重制约了进一步勘探。为此,基于钻井及地震资... 鄂尔多斯盆地彬长地区下古生界风化壳岩溶储层勘探前景良好,是实现油气突破和未来增储上产的重要阵地。但该区勘探程度低,风化壳岩溶储层尚未进行系统研究,储层发育特征及分布规律认识不清,严重制约了进一步勘探。为此,基于钻井及地震资料,剖析了研究区储层发育特征,明确了储层形成主控因素,建立了发育模式,并预测了其分布。结果表明,彬长地区下古生界风化壳岩溶储层岩性多样,主要为鲕粒云岩、鲕粒灰岩、粉—细晶白云岩等,储集空间以溶蚀孔洞、裂缝为主,可见晶间孔;古地貌及断裂是储层发育主控因素,岩溶储层主要发育于断裂发育的残丘地貌。综合考虑风化壳岩溶储层形成主控因素及平面分布,彬长地区风化壳岩溶可分为4类区:类型Ⅰ为有利储层发育区,与加里东期断层及裂缝分布相关,聚集分布,规模大,断裂对岩溶影响较强,岩溶储层品质好;类型Ⅱ为次有利储层发育区,分布于北西向小型走滑断裂附近,断裂对岩溶影响小,岩溶储层品质较好,分布有限;类型Ⅲ为较有利储层发育区,与古生界裂缝有关,断裂不发育,对岩溶影响弱,风化壳岩溶储层零星分布;类型Ⅳ为不利储层区,与燕山—喜山期构造运动改造形成的线性大断层有关,分布规模大,但处于侵蚀高地,剥蚀作用强,储层品质差。 展开更多
关键词 风化壳岩溶储层 主控因素 发育模式 分布规律 下古生界 彬长地区
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西华夏块体深地震测深远炮检距PmP'波组属性?
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作者 刘汉奇 王夫运 +3 位作者 宋佳佳 王帅军 宋向辉 张雪莹 《地球物理学进展》 北大核心 2025年第2期432-439,共8页
西华夏块体深地震测深资料观测长度超过250 km或更远的地震记录截面中,远炮检距的PmP'波组具有几何形态平坦、视速度较低、位于折合走时零线以上的显著特征.由于其与PmP反射波组相连且波形相似,常规的波组识别常常当作PmP波组的一部... 西华夏块体深地震测深资料观测长度超过250 km或更远的地震记录截面中,远炮检距的PmP'波组具有几何形态平坦、视速度较低、位于折合走时零线以上的显著特征.由于其与PmP反射波组相连且波形相似,常规的波组识别常常当作PmP波组的一部分.把这个波组作为PmP波组部分进行理论地震图模拟,其走时和振幅均难以同时获得满意的拟合.以2021年粤东地区连平—河源—海丰地震宽角反射/折射剖面SP3炮远炮检距PmP'波组为例,计算得到该波组最远端的视速度为6.04 km/s,小于用临界区域PmP波组走时算出的地壳平均P波速度6.27 km/s,表明该波组不具有PmP波组属性.用新的下地壳和莫霍界面模型对PmP'波组进行二维理论地震图拟合,结果显示,这一波组是来自下地壳的回折波,表明西华夏块体下地壳普遍具有正速度梯度结构特征,反映了华南地区东南缘中生代以来岩浆底侵的结果,可能是新生地壳的证据. 展开更多
关键词 西华夏地块 深地震测深远炮检距PmP'波组 波组运动学定量分析 理论地震图模拟 下地壳模型
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宁夏中南部弧形构造带至鄂尔多斯地块西缘深部电性结构特征
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作者 周鹏超 陈宣华 +3 位作者 侯芳 邵兆刚 叶高峰 余苇 《地球物理学报》 北大核心 2025年第10期3869-3886,共18页
宁夏中南部弧形构造带处在鄂尔多斯地块、阿拉善地块和祁连地块之间的过渡地区,其东部为鄂尔多斯地块,两者以固原-青铜峡断裂为界.本文依据超宽频/宽频大地电磁测深剖面,阐述了宁夏中南部弧形构造带至鄂尔多斯地块西缘深部电性结构特征... 宁夏中南部弧形构造带处在鄂尔多斯地块、阿拉善地块和祁连地块之间的过渡地区,其东部为鄂尔多斯地块,两者以固原-青铜峡断裂为界.本文依据超宽频/宽频大地电磁测深剖面,阐述了宁夏中南部弧形构造带至鄂尔多斯地块西缘深部电性结构特征.固原-青铜峡断裂两侧的鄂尔多斯地块与祁连地块具有完全不同的电性结构.祁连地块岩石圈总体具有较高的电阻率,其深部30 km左右近水平的异常低阻(高导)层很可能为地块拼接带低阻表壳物质(洋壳)向南西俯冲到祁连地块之下的古俯冲带残余结构.地块拼贴带浅部存在无根中阻体,深部电阻率总体较小,可能存在上地幔到地壳的热流通道,使得软流圈物质上涌.鄂尔多斯地块西缘冲断带岩石圈电阻率总体较高;而天环坳陷表层则具有低阻的层状特征,基底为轻微褶皱的次高阻层,其深部存在地幔隆起,很可能与岩石圈减薄和拆沉作用有关.祁连地块和鄂尔多斯地块深部岩石圈接触关系可能为硬碰撞.而祁连地块至鄂尔多斯地块西缘地壳内部则经历了挤压性的滑脱作用,在地壳尺度上形成了一系列叠瓦式逆冲构造,青藏高原东北缘的地壳增厚机制可能为地壳整体增厚模式. 展开更多
关键词 弧形构造带 鄂尔多斯地块西缘 电性结构 大地电磁 叠瓦式逆冲构造 地壳整体增厚模式
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深海富钴结壳资源评价方法研究进展
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作者 杨耀民 任悦 +3 位作者 刘永刚 李超 刘震 周鑫原 《海洋科学进展》 北大核心 2025年第1期1-17,共17页
富钴结壳超常富集锰(Mn)、钴(Co)、镍(Ni)、铜(Cu)、稀土(REE)和铂族元素(PGE)等稀有金属。我国科研人员先后利用算术平均法、邻近区域法、地质块段法、地质统计学(克里金法)、网格剖分积分法和分形理论法等,开展了富钴结壳资源评价以... 富钴结壳超常富集锰(Mn)、钴(Co)、镍(Ni)、铜(Cu)、稀土(REE)和铂族元素(PGE)等稀有金属。我国科研人员先后利用算术平均法、邻近区域法、地质块段法、地质统计学(克里金法)、网格剖分积分法和分形理论法等,开展了富钴结壳资源评价以及资源量的评估,以支撑我国与国际海底管理局2014年签订的富钴结壳勘探合同区的区域放弃工作。本文对目前富钴结壳资源评价方法进行了系统梳理,深入探讨了富钴结壳资源评价的主要方法及优缺点,并根据重要性划分了富钴结壳资源评价参数级别。此外,提出利用大数据和人工智能技术构建深海结壳矿床的三维实体模型,利用机器学习等先进技术进行多元地学信息的富钴结壳资源智能评价。 展开更多
关键词 富钴结壳 战略性矿产资源 资源评价 三维实体模型 机器学习
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植物固沙最低盖度的理论计算
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作者 王洋 王振亭 《中国沙漠》 北大核心 2025年第2期97-101,共5页
人工植被作为传统防风固沙措施的核心,其最低盖度是治沙工程设计与施工的关键参数。本文利用前人建立的植被与生物土壤结皮耦合动力学模型,计算地表稳定状态下的最低植被盖度。主要结论:(1)该模型可望成为植物固沙的理论依据;(2)当输沙... 人工植被作为传统防风固沙措施的核心,其最低盖度是治沙工程设计与施工的关键参数。本文利用前人建立的植被与生物土壤结皮耦合动力学模型,计算地表稳定状态下的最低植被盖度。主要结论:(1)该模型可望成为植物固沙的理论依据;(2)当输沙势高且降雨量低时,存在以植物或生物土壤结皮覆盖为主的两种稳定地表,植物固沙的最低盖度为0.02~0.12;(3)根据年降水量与输沙势,可将河西走廊沙区划分为自然恢复、植物固沙和工程固沙三类区域,以便因地制宜地制订精准固沙策略。 展开更多
关键词 防风固沙 植被 生物土壤结皮 耦合模型 最低盖度
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基于SfM近景摄影测量技术的藓结皮坡面风蚀监测
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作者 陈浩然 高丽倩 +2 位作者 郭雅丽 欧阳文峰 张采月 《农业工程学报》 北大核心 2025年第7期129-135,共7页
生物结皮作为干旱半干旱地区重要的地表覆被物,在土壤风蚀防控中发挥着重要作用。生物结皮坡面的风蚀速率监测和风蚀形态变化是坡面风蚀过程和风蚀机理研究的重点与难点。该研究以黄土高原不同盖度的藓结皮坡面为研究对象,通过运动恢复... 生物结皮作为干旱半干旱地区重要的地表覆被物,在土壤风蚀防控中发挥着重要作用。生物结皮坡面的风蚀速率监测和风蚀形态变化是坡面风蚀过程和风蚀机理研究的重点与难点。该研究以黄土高原不同盖度的藓结皮坡面为研究对象,通过运动恢复结构(structure-from-motion,SfM)近景摄影测量技术结合室内风洞试验,评价了SfM近景摄影测量技术对藓结皮坡面土壤风蚀速率测量的精度及其在生物结皮坡面土壤风蚀监测中的应用可行性。结果表明:SfM近景摄影测量技术能够准确获取藓结皮坡面土壤风蚀速率,均方根误差(root mean square error,RMSE)范围为0.003~0.094 kg/(m^(2)·min)。在藓结皮盖度为0~60%条件下,实测风蚀速率为0.069~0.557 kg/(m^(2)·min),SfM近景摄影测量技术估测风蚀速率为0.068~0.510kg/(m^(2)·min),估测平均绝对误差为0.002~0.092kg/(m^(2)·min),估测相对误差为2.81%~16.33%,整体精度较高。同时数字高程模型(digital elevation model,DEM)重建坐标误差较低,误差范围为0.145~0.302 mm,坐标重建均方根误差为0.232 mm,能够准确获取藓结皮坡面风蚀前后的高程数据。因此,SfM近景摄影测量技术为生物结皮坡面的土壤风蚀监测提供了一种非接触式、高效且可靠的手段,具有重要的应用价值。 展开更多
关键词 运动恢复结构 生物结皮 土壤风蚀监测 数字高程模型
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Crustal Structure across the Northwestern Margin of South China Sea:Evidence for Magma-poor Rifting from a Wide-angle Seismic Profile 被引量:15
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作者 DING Weiwei Michael SCHNABEL +2 位作者 Dieter FRANKE RUAN Aiguo WU Zhenli 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第4期854-866,共13页
We present results from a 484 km wide-angle seismic profilie acquired in the northwest part of the South China Sea (SCS) during OBS2006 cruise. The line that runs along a previously acquired multi-channel seismic li... We present results from a 484 km wide-angle seismic profilie acquired in the northwest part of the South China Sea (SCS) during OBS2006 cruise. The line that runs along a previously acquired multi-channel seismic line (SO49-18) crosses the continental slope of the northern margin, the Northwest Subbasin (NWSB) of the South China Sea, the Zhongsha Massif and partly the oceanic basin of the South China Sea. Seismic sections recorded on 13 ocean-bottom seismometers were used to identify refracted phases from the crustal layer and also reflected phases from the crust-mantle boundary (Moho). Inversion of the traveltimes using a simple start model reveals crustal images in the study area. The velocity model shows that crustal thickness below the continental slope is between 14 and 23 kin. The continental part of the line is characterized by gentle landward mantle uplift and an abrupt oeeanward one. The velocities in the lower crust do not exceed 6.9 km/s. With the new data we can exclude a high-velocity lower crustal body (velocities above 7.0 kin/s) at the location of the line. We conclude that this part of the South China Sea margin developed by a magma-poor rifting. Both, the NWSB and the Southwest Sub-basin (SWSB) reveal velocities typical for oceanic crust with crustal thickness between 5 and 7 kin. The Zhongsha Massif in between is extremely stretched with only 6-10 km continental crust left. Crustal velocity is below 6.5 kin/s; possibly indicating the absence of the lower crust. Multi-channel seismic profile shows that the Yitongansha Uplift in the slope area and the Zhongsha Massif are only mildly deformed. We considered them as rigid continent blocks which acted as rift shoulders of the main rift subsequently resulting in the formation of the Northwest Sub-basin. The extension was mainly accommodated by a ductile lower crustal flows, which might have been extremely attenuated and flow into the oceanic basin during the spreading stage. We compared the crustal structures along the northern margin and found an east-west thicken trend of the crust below the continent slope. This might be contributed by the east-west sea-floor spreading along the continental margin. 展开更多
关键词 P-WAVE velocity model magma-poor rifting lower crust flow South China Sea
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Numerical analyses of pile performance in laterally spreading frozen ground crust overlying liquefiable soils 被引量:7
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作者 Xiaoyu Ryan Zhang Zhaohui Joey Yang 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2018年第3期491-499,共9页
Lateral spread of frozen ground crust over liquefied soil has caused extensive bridge foundation damage in the past winter earthquakes.A shake table experiment was conducted to investigate the performance of a model p... Lateral spread of frozen ground crust over liquefied soil has caused extensive bridge foundation damage in the past winter earthquakes.A shake table experiment was conducted to investigate the performance of a model pile in this scenario and revealed unique pile failure mechanisms.The modelling results provided valuable data for validating numerical models.This paper presents analyses and results of this experiment using two numerical modeling approaches: solid-fluid coupled finite element(FE) modeling and the beam-on-nonlinear-Winkler-foundation(BNWF) method.A FE model was constructed based on the experiment configuration and subjected to earthquake loading.Soil and pile response results were presented and compared with experimental results to validate this model.The BNWF method was used to predict the pile response and failure mechanism.A p-y curve was presented for modelling the frozen ground crust with the free-field displacement from the experiment as loading.Pile responses were presented and compared with those of the experiment and FE model.It was concluded that the coupled FE model was effective in predicting formation of three plastic hinges at ground surface,ground crust-liquefiable soil interface and within the medium dense sand layer,while the BNWF method was only able to predict the latter two. 展开更多
关键词 frozen ground crust lateral spread Finite Element (FE) modeling BNWF method
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Crust1.0地壳模型及其应用:以长江中下游成矿带为例 被引量:6
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作者 罗凡 严加永 +3 位作者 付光明 罗磊 陶鑫 王昊 《地质学报》 EI CAS CSCD 北大核心 2020年第2期648-660,共13页
地壳是地球系统的重要组成部分,了解各圈层的结构及相互作用是研究地球物质深部交互过程的核心问题,如何探测地壳内部的物质组成和形态结构一直是地球系统科学的研究热点。随着海量地球探测数据的积累和挖掘,地球科学学家提出了不同细... 地壳是地球系统的重要组成部分,了解各圈层的结构及相互作用是研究地球物质深部交互过程的核心问题,如何探测地壳内部的物质组成和形态结构一直是地球系统科学的研究热点。随着海量地球探测数据的积累和挖掘,地球科学学家提出了不同细节层次的地壳模型,当前最为详细,分辨率最高的全球地壳模型是Crust1.0地壳模型。本文首先详细介绍了Crust1.0地壳模型沉积层厚度和壳幔密度差的数据来源和分布特征。然后,基于Crust1.0地壳模型信息,对长江中下游成矿带及邻区的卫星重力数据进行沉积层校正后,采用变密度界面计算方法,获得的长江中下游地区的Moho界面深度分布。长江中下游成矿带的Moho面形态呈现为"V"字型幔隆带,通过分析矿床、岩体及深大断裂的分布规律与幔隆带形成的关系,进一步证实了长江中下游成矿带深部的地幔隆起是形成巨型矿床的根本原因。研究结果表明,Crust1.0在研究区域地壳结构、成矿动力学深部背景等基础地学和地球系统科学研究中具有广泛的应用前景。 展开更多
关键词 全球地壳模型 crust1.0 变密度界面反演 长江中下游成矿带 MOHO
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Crust改进算法的点云网格自动构建 被引量:1
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作者 陈喆 王健 +2 位作者 梁周雁 孙文潇 马伟丽 《测绘科学》 CSCD 北大核心 2018年第12期98-104,117,共8页
针对逆向工程、智慧城市和文物保护等领域中复杂散乱点云建模自动化程度低、精度差的问题,该文在Crust算法的基础上,对最佳三角形的判断方法进行改进。首先计算采样点的Voronoi图和极点,将Voronoi顶点和极点组成新的点集并进行Delaunay... 针对逆向工程、智慧城市和文物保护等领域中复杂散乱点云建模自动化程度低、精度差的问题,该文在Crust算法的基础上,对最佳三角形的判断方法进行改进。首先计算采样点的Voronoi图和极点,将Voronoi顶点和极点组成新的点集并进行Delaunay三角剖分,生成粗三角网格,建立四面体与三角形的对应关系;然后根据克拉默法则求解每个四面体的中心坐标,通过相邻两个四面体中心的欧式距离求解交叉系数,删除不符合标准的三角形;最终构建出完整、高精度的三角网格。经实验验证:该算法对于不同质量、不同密度的点云均有很好的适用性,能够实现散乱点云实体网格的自动构建,并且精度较高。 展开更多
关键词 点云 建模 crust算法 三角网格
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Nd Isotopic and Model Age Study of the Shandong Province, North China Craton: Implications for Correlation with South Korea 被引量:1
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作者 Feifei Liu Yaoqi Zhou 《Journal of Earth Science》 SCIE CAS CSCD 2019年第5期938-951,共14页
The geological units in Shandong Province, North China are important parts of the North China Craton and offer important insights into their crustal evolutionary history. This paper presents 611 sets of Nd isotopic da... The geological units in Shandong Province, North China are important parts of the North China Craton and offer important insights into their crustal evolutionary history. This paper presents 611 sets of Nd isotopic data of Archean–Mesozoic rocks from Shandong including the Luxi, Jiaobei, and Sulu terranes, which provides important constraints for crustal growth and reactivation. Nd-depleted mantle model ages(TDM) of Archean rocks with positive εNd(t) values showed that ca. 2.9 and 2.8–2.7 Ga were the most important periods of crustal growth in the Jiaobei and Luxi terranes, respectively, while the period of ca. 2.6–2.5 Ga in the Jiaobei terrane likely indicates a coherent event of crustal growth and reworking. During the Proterozoic, multi-stage rifting and collisional orogenic events possibly led to the reworking of Archean crust in the source region. The Nd isotopic data of the Paleoproterozoic and Neoproterozoic rocks from Sulu indicated significant reworking of older crust with juvenile magmatic input. Crustal reactivation occurred during the Mesozoic. The younger TDM ages of the Mesozoic rocks with low negative εNd(t) values indicate that a juvenile crustal/mantle component was added to the ancient basement. The reactivation reflectes significant crust-mantle interaction via the mechanism of crustal subduction and mantle-derived magma underplating, or possibly asthenospheric upwelling. In addition, the crustal correlation between Shandong and Korea(including the Gyeonggi massif, Ogcheon belt, and Yeongnam massif) is established in this study. The TDM age distribution provides evidence favoring the affinity relationship between the Gyeonggi massif and Ogcheon belt of South Korea and the Jiaobei and Sulu terranes of Shandong, while the Yeongnam massif is more correlated with the South China Block. 展开更多
关键词 ND model age crustAL growth crust REACTIVATION Shandong geochemistry Korea
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