关于秦岭造山带   总被引：4，自引：4，他引：0  

张国伟  郭安林  董云鹏  姚安平 《地质力学学报》2019,25(5):746-768

纪念老一代地球科学家李四光先生,思考地球科学与大地构造学的创新发展。文章以秦岭造山带为例思考大陆复合造山及其动力学,认知概括秦岭造山带基本属性与特质,探索认识中小多板块多期洋陆俯冲造山-陆-陆板块俯冲碰撞造山的板块复合造山,并又强烈叠加复合陆内造山,造成复杂组成与结构,形成立交桥式四维流变学分层的多层非耦合动态演化的大陆复合造山带模型,及其新的演化趋势动态和构成国家人类需求的成矿成藏物质财富与宜居的地表系统环境等,期望前瞻探索认知地球发展的未来。文章还就秦岭造山带几个有争议的问题,进行简要讨论,共求新的探索研究发展。期盼学习李四光先生学术理论精华,尤其在深化发展板块构造,探索认知大陆构造与动力学方面,创新发展地质力学,以宇宙太阳系视野探索地球动力学,推动大地构造新发展。   相似文献   

内蒙古扎鲁特旗巴尔哲超大型矿床控矿因素分析     

陈金勇  范洪海  王生云  张闯  赵敬洋  耿瑞瑞 《地质力学学报》2019,25(1):27-35

内蒙古巴尔哲矿床不仅是超大型的REE-Zr-Nb-Ta-Be多金属矿床,同时也是大型的U-Th矿床。通过野外地质观察、地面伽玛能谱测量、岩矿鉴定和室内数据处理等,发现铀、钍主要以类质同像的形式存在于矿石矿物中;铍和稀土元素的独立矿物以羟硅铍钇铈矿和独居石为主;铌、钽、锆主要赋存在铌铁矿、烧绿石和锆石中。另外,从构造、岩性及蚀变特征三方面,对巴尔哲矿床的控矿因素进行了详细解剖,研究表明,巴尔哲矿床的铀钍矿化与稀有稀土矿化密切共生,均赋存于强蚀变钠闪石花岗岩中,蚀变主要为钠长石化和硅化。该矿床主要受构造和碱性花岗岩体的控制,是构造和碱性花岗质岩浆演化的耦合产物。   相似文献   

东海陆架盆地南部中生代演化与动力学转换过程     

杨长清  杨传胜  孙晶  杨艳秋 《吉林大学学报(地球科学版)》2019,49(1):139-153

东海陆架盆地处于欧亚板块东南缘,其构造演化、动力学机制转换同太平洋板块与欧亚板块碰撞及印度-澳大利亚板块远程推挤效应有关。中生代以来,该盆地形成和演化过程受到古太平洋板块多期俯冲及多构造体系的叠加改造,地质构造和地球物理场复杂,盆地演化及动力学过程等一直是争论的焦点。本文利用最新调查资料,通过构造物理模拟实验、构造解析和平衡地质复原剖面等方法,结合区域构造背景,系统分析了东海陆架盆地中生代演化过程,探讨了其构造动力学转换过程。研究认为东海陆架盆地自中生代以来经历了晚三叠世前的被动大陆边缘和晚三叠世-中侏罗世活动大陆边缘挤压坳陷型盆地阶段,挤压应力来源于伊泽奈崎板块向欧亚大陆板块的低角度俯冲;早白垩世晚期-晚白垩世活动陆缘伸展断陷型盆地阶段,应力来源于太平洋板块向欧亚大陆板块俯冲后撤导致的岩石圈减薄作用;古近纪为弧后伸展断陷型盆地阶段。同时认为东海陆架盆地古特提斯构造域向古太平洋构造域转换的时间应该发生在中三叠世末期,古太平洋板块低角度俯冲和俯冲后撤代表华南中生代深部地质过程。  相似文献   

High resolution facies architecture and digital outcrop modeling of the Sandakan formation sandstone reservoir,Borneo:Implications for reservoir characterization and flow simulation     

Numair A.Siddiqui  Mu.Ramkumar  Abdul Hadi A.Rahman  Manoj J.Mathew  M.Santosh  Chow W.Sum  David Menier 《地学前缘(英文版)》2019,10(3):957-971

Advances in photogrammetry have eased the acquisition of high-resolution digital information from outcrops, enabling faster, non-destructive data capturing and improved reservoir modeling. Geocellular models for flow dynamics with in the virtual outcrop in siliciclastic deposits at different sets of sandstone facies architecture remain, however, a challenge. Digital maps of bedding, lithological contrast, spatial-temporal variations of bedding and permeability characteristics make it more easy to understand flow tortuosity in a particular architecture. An ability to precisely model these properties can improve reservoir characterization and flow modeling at different scales. Here we demonstrate the construction of realistic 2 D sandstone facies based models for a pragmatic simulation of flow dynamics using a combination of digital point clouds dataset acquired from LiDAR and field investigation of the Sandakan Formation, Sabah, Borneo.Additionally, we present methods for enhancing the accuracy of outcrop digital datasets for producing high resolution flow simulation. A well-exposed outcrop from the Sandakan Formation, Sabah, northwest Borneo having a lateral extent of 750 m was chosen in order to implement our research approach. Sandstone facies and its connectivity are well constrained by outcrop observations, data from air-permeability measurements, bilinear interpolation of permeability, grid construction and water vector analysis for flow dynamics.These proportions were then enumerated in terms of static digital outcrop model(DOM) and facies model based on sandstone facies bedding characteristics. Flow simulation of water vector analysis through each of the four sandstone facies types show persistent spatial correlation of permeability that align with either cross-bedded orientation or straight with more dispersion high quality sandstone(porosity 21.25%-41.2%and permeability 1265.20-5986.25 mD) and moderate quality sandstone(porosity 10.44%-28.75% and permeability 21.44-1023.33 mD). Whereas, in more heterolithic sandstone(wavy-to flaser-bedded and bioturbated sandstone), lateral variations in permeability show spatially non-correlated patterns over centimeters to tens of meters with mostly of low quality sandstone(porosity 3.4%-12.31% and permeability < 1 mD to 3.21 mD). These variations reflect the lateral juxtaposition in flow dynamics. It has also been resulted that the vertical connectivity and heterogeneities in terms of flow are mostly pragmatic due to the interconnected sandstone rather than the quality of sandstone.  相似文献   

Timings of early crustal activity in southern highlands of Mars:Periods of crustal stretching and shortening     

Trishit Ruj  Goro Komatsu  Jan Hendrik Pasckert  James M.Dohm 《地学前缘(英文版)》2019,10(3):1029-1037

Extensional and compressional structures are globally abundant on Mars. Distribution of these structures and their ages constrain the crustal stress state and tectonic evolution of the planet. Here in this paper, we report on our investigation over the distribution of the tectonic structures and timings of the associated stress fields from the Noachis-Sabaea region. Thereafter, we hypothesize possible origins in relation to the internal/external processes through detailed morphostructural mapping. In doing so, we have extracted the absolute model ages of these linear tectonic structures using crater size-frequency distribution measurements, buffered crater counting in particular. The estimated ages indicate that the tectonic structures are younger than the mega impacts events(especially Hellas) and instead they reveal two dominant phases of interior dynamics prevailing on the southern highlands, firstly the extensional phase terminating around3.8 Ga forming grabens and then compressional phase around 3.5-3.6 Ga producing wrinkle ridges and lobate scarps. These derived absolute model ages of the grabens exhibit the age ca. 100 Ma younger than the previously documented end of the global extensional phase. The following compressional activity corresponds to the peak of global contraction period in Early Hesperian. Therefore, we conclude that the planet wide heat loss mechanism, involving crustal stretching coupled with gravitationally driven relaxation(i.e.,lithospheric mobility) resulted in the extensional structures around Late Noachian(around 3.8 Ga). Lately cooling related global contraction generated compressional stress ensuing shortening of the upper crust of the southern highlands at the Early Hesperian period(around 3.5-3.6 Ga).  相似文献   

Temporal and spatial evolution of surface sediments characteristics in the Dagu River estuary and their dynamic response mechanism     

《China Geology》2019,2(3):325-332

Based on the 39 surface sediment samples collected in the flood season and the dry season in 2012 respectively and the measured hydrological data in October 2012, the sediment grain size characteristics has been analyzed and the response mechanism of surface sediments to estuarine hydrodynamics was revealed by calculating the range of waves and tidal currents. The results show that: (1) The grain size of the surface sediment samples decreased gradually from land to sea in the flood season. The fine sediment was redistributed under marine hydrodynamics in the dry season and the sediments showed coarser tendency ingeneral; (2) tidal current stirring sediment was very obvious in Dagu River estuary area, and wave stirring sediments mainly occurred in the tidal flat area and estuary sand bar area; (3) in the flood season, surface sediment sat the estuary were transported towards south and southeast. In the dry season, surface sediments were transported towards southwest at the north area of Jiaozhou Bay Bridge, and sediments were transported towards northeast area at the south of Jiaozhou Bay Bridge.  相似文献   

油井动态与地震关系研究的新进展   总被引：3，自引：0，他引：3  

刘元生  张昭栋  何钧  吴建国 《华北地震科学》2004,22(4):1-7

对油井动态与地震关系进行了系统、深入研究,取得了新的进展,给出了油井动态多种观测参数间定量的相互关系数学表达式,给出了由油井压(水位)的变化反演含油(水)层应力变化的定量计算方法与程序,给出了多维的时、空、强大区域应力场的演化图像,给出了较科学的油井动态数据处理方法,对动态异常演化的时空分布特征与观测点所处的构造位置进行综合研究。  相似文献   

广西珍珠湾红树种群结构与动态特征          下载免费PDF全文

宁秋云  赖廷和  曹庆先  莫珍妮  李英花  何斌源 《应用海洋学学报》2022,41(1):42-52

本研究以种群生命表为基础,对位于广西珍珠湾内的桐花树(Aegiceras corniculatum)种群、白骨壤(Avicennia marina)种群、秋茄(Kandelia obovata)种群和木榄(Bruguiera gymnorrhiza)种群采用径级法及匀滑技术,编制种群特定时间生命表,绘制种群存活曲线、死...  相似文献   

Tracking historical storm records from high-barrier lagoon deposits on the southeastern coast of Hainan Island,China     

Liang Zhou  Xiaomei Xu  Yaping Wang  Jianjun Jia  Yang Yang  Gaocong Li  Changliang Tong  Shu Gao 《海洋学报(英文版)》2021,40(11):162-175

The relationship between storm activity and global warming remains uncertain. To better understand storm–climate relationships, coastal lagoon deposits are increasingly being investigated because they could provide high-resolution storm records long enough to cover past climate changes. However, site-specific sediment dynamics and high barriers may bias storm reconstructions. Here, we aimed to investigate these factors through the reconstruction of five distinct storm records (XCL-01, XC-03, XC-06, XC-07, XC-08) from different water depths in a lagoon with a high barrier (i.e., Xincun Lagoon of Hainan Island). Sediment cores were characterized using high-resolution grain size and XRF measurements, to identify storm events. These data were coupled with a numerical simulation to obtain bed shear stress data with high-spatial resolution to better understand storm-induced sediment transport mechanisms. 210Pb dating and Pb pollution chronostratigraphic markers indicated that the chronology of the storm deposit sequences of the cores span the period between 117 a and 348 a. The grain size and XRF results indicated numerous, highly variable and short-duration fluctuations, suggesting that storm-induced coarse-grained sediments were deposited at these core sites. The inconsistent storm events recorded in these cores suggest that these sites have different preservation potentials for storm deposits. However, the consistence between storm sediment records and historical documents for Core XCL-01 indicates that high-barrier lagoons could provide long-term storm event records with high preservation potential.  相似文献   

珊瑚岛礁海岸多尺度波流运动特性研究新进展     

郑金海  时健  陈松贵 《热带海洋学报》2021,40(3):44-56

珊瑚岛礁海岸波流动力复杂、地貌形态特殊、工程响应未知, 波浪传播变形和波生环流对建筑物安全、地形地貌演变、防灾减灾和生态环境保护都有重要影响。本文从大范围大洋海脊导波与岛礁波浪俘获、中等尺度的礁坪-潟湖-裂口系统波流特性、建筑物前沿的局部波流特性及工程响应等三种不同空间尺度上综述了波流运动特性研究的新进展, 主要包括深水大范围的海脊波浪引导与岛礁波浪俘获的理论解析、礁坪-潟湖-裂口系统整体物理模型实验、基于大水槽实验的建筑物影响下波流演化过程及越浪量和波浪力计算方法, 并提出亟需深入研究的重点内容。  相似文献