东海陆架外缘区构造特征及其成因机制

东海陆架边缘的构造特征记录了有关冲绳海槽张裂过程的关键信息,对于进一步理解海槽的形成演化以及弧后张裂与弧-陆碰撞之间的相互作用至关重要。本文基于多道地震和重磁资料,分析了东海陆架边缘的地形和构造特征,并对冲绳海槽早期张裂过程、北西向断裂带的分隔控制作用、钓鱼岛隆起带南北构造差异和冲绳海槽的向西前展等问题进行了探讨。结果表明,冲绳海槽西侧陆坡存在的分段性,各分段在地形地貌、地层展布和构造特征等方面的不同,体现了其构造演化和现今构造活动性的差异。冲绳海槽中—北段的张裂始于陆架前缘坳陷,在晚中新世向东扩展至整个海槽,晚中新世至今以分散式张裂为主。北西向断裂带对东海陆架边缘不同分段的构造特征和构造活动起到了分隔控制和转换协调作用,控制了不同类型陆坡的形成和发育。受冲绳海槽在全宽度上向西前展的影响,钓鱼岛隆起带南段的基底隆起及其支撑的陆架边缘发生了破坏和沉降,形成基底起伏较大、地形崎岖不平的陆坡。     

海洋地球物理学和海洋地质学的发展

回顾了20世纪60年代板块学说的诞生,以及海洋地球物理学及海洋地球物理学家对这场地球科学革命所做出的巨大贡献。二次世界大战中,海洋技术飞速进步;战后,西方国家的海洋地球物理学家利用这些技术在海上开展了广泛的地球物理调查,积累了大量资料,有了许多重要发现。大洋地震带原来是一条裂谷带;大洋地磁场存在以中脊为中心,向两边正负相间的对称异常条带;大洋底沉积很薄,且从中脊向两边逐步加厚;大洋地壳仅厚数千米,而大陆地壳厚达30千米以上;大洋中脊处热流值很高,向两边逐步减小;地球的地震波速度从地表到约深80 km逐步增大,从80 km深度处速度开始减小,说明地球表层存在岩石圈,其下部存在软流圈;在海沟处,地震震中分布从海沟开始,向下沿约45°倾角到700 km深处,这可能是大洋岩石圈俯冲之处。由此地球科学家提出了板块构造假说,认为地幔深处的岩浆沿大洋中脊处向上运移,在海底处不断产生新洋壳;新洋壳(岩石圈)不断向两边运动,在海沟处向大陆岩石圈之下俯冲、消亡;当大洋岩石圈俯冲消亡之后,两边的大陆就发生碰撞,形成造山带,因此,地球上最老的大陆年龄达38亿年,而大洋岩石圈最老年龄只有1.8亿年。板块构造学说坚持活动论,是大陆漂移假说的发展之结果,更是地球科学深刻革命的开始。当它上陆之后,地球科学就掀起了革命的风暴。     

北京西山煤田滑脱构造的遥感研究

本文利用多种遥感资料提供的大量的新的构造信息,对北京西山煤田已有的地质认识和成果进行了重要补充和修改,划分出推覆型和滑型两种基本类型的滑脱构造,并详细研究了各个滑脱构造系统的影像特征、展布规律、几何形态、成因机制、演化历史以及控煤作用。     

《东北地区1：150万大地构造相图》的编制

东北地区1：150万大地构造相图是2018年出版的一份区域性大地构造图.该图依据不断积累和丰富的基础地质资料,将大地构造理论研究与综合应用汇总和集成,是东北地区科技创新成果和技术方法进步转化应用的重要体现.此次编图以板块构造理论和大陆动力学思维为指导,以多岛洋、弧-盆系发展演化观点为切入点,运用大地构造相分析方法,研究东北地区地壳形成、演化历史,以及大地构造环境及其与成矿作用的时空关系.较系统地阐述了东北地区的岩石构造组合、建造构造与构造演化阶段的宏观背景.     

新疆北部石炭纪地层、岩相古地理与烃源岩

依据近几年新疆区域地质调查结果,结合新疆油田与吐哈油田最新勘探成果,通过区域构造背景和沉积充填演化特征推断石炭系沉积建造样式,理顺了新疆北疆地区石炭纪地层层序,目的是推断石炭纪烃源岩发育层段与主力生烃区范围。下石炭统有效烃源岩分布较广,主要发育于北疆西准噶尔达尔布特山前、博格达山前、准噶尔东部陆东—五彩湾地区早石炭世被动陆缘海相和海陆过渡相沉积盆地;上石炭统有效烃源岩分布相对局限,主要发育于东准噶尔克拉美丽山前石钱滩区、布尔津—吉木乃区及库普—三塘湖区海陆过渡相沉积盆地内。石炭系油气成藏严格遵循"源控论",有效生烃区决定其有效成藏范围,所伴随发育的火山岩体决定其富集程度。优选西准噶尔、东准噶尔、库普—三塘湖区、博格达山前区、布尔津—吉木乃区石炭系烃源岩发育区及其相邻构造带,作为今后石炭系油气勘探战略选区的重要领域和区带。     

Note on rain-triggered earthquakes and their dependence on karst geology

Recently reported rain-triggered seismicity from three separate storms occurred exclusively in karst geology. In this paper, I discuss how the hydrogeology of karst controls rain-triggered seismicity by channeling of the watershed after intense rainfall directly into the karst network. Such channeling results in very large increases in hydraulic head, and more importantly, substantially increases the vertical stress acting on the underlying pore-elastic media. Rapid loading upon a pore-elastic media induces seismicity by increasing pore pressure at depth in a manner similar to that observed from reservoir impounding. Using a simple 1-D model of a pore-elastic medium, it is shown that the instantaneous fluid pressure increase at depth is a substantial fraction of the pressure step applied at the boundary, followed by time-dependent pore pressure increases associated with the typical linear diffusion problem. These results have implications for the change in fluid pressure necessary to trigger earthquakes, and leads to the following hypothesis to be tested: Unambiguous rain-triggered seismicity will only occur in karst regions.     

板块构造环境对金矿成矿的控制作用

以板块构造理论为基础，论述了板块构造与金矿成矿的关系，指出与金矿有关的主要板块构造环境是裂谷带，岛弧地带，深大断裂带和碰撞带，不同大地构造环境对金矿成矿的控制具有不同的特点，另一方面，不同板块构造环境对金矿成矿具有专属性，这种专属性随着板块间的相互作用及其旋回性发展具有时空复合特征。     

拆离构造动力学与地洼理论

拆离构造是当前地学中的研究热点,对其研究具有重要的理论与经济意义。在20世纪90年代初,笔者应《铀矿地质》编辑部之约,以“拆离构造理论与找矿实践”命题分八个方面在“铀矿地质”期刊断续刊登,其内容涉及:(1)拆离构造在我国研究的新进展;(2)拆离构造概念的演化与地球圈层;(3)拆离构造基本含义与相关构造术语;(4)拆离构造形成的动力学讨论;(5)拆离构造的厘定和鉴别;(6)拆离构造的研究方法;(7)拆离构造控矿理论与找矿;(8)拆离构造研究展望。本文仅就拆离构造的动力学机制研究和地洼理论在拆离构造动力学研究中的应用作简要论叙,并以此草文敬献陈国达院士九十华诞以兹纪念。     

A geomorphic framework for understanding the surface archaeological record in arid environments

The Narcao and Cixerri basins in Southwestern Sardinia are east-west trending basins of Oligocene age. Recent geological mapping, combined with structural and stratigraphical analyses, support the proposed hypothesis that these basins were very open growth synclines confined within a structural high, delimited by northwest trending dextral strike slip faults. Previously the basins have been interpreted as fault-bounded grabens. The newer revised interpretation is consistent with the existence of NNW trending dextral strike-slip dynamic, related to a north-south shortening which has generated reverse faulting and tight folds in the underlying, pre-synclinal evolution, Eocene succession. This deformation, along with an interfering sub-orthogonal thrust and fold system which affects the Mesozoic sequence, was traditionally linked to the Pyrenean Orogenesis. The Oligocene–Aquitanian shortening, which resulted in the growth synclines and strike-slip faulting, is consistent with the structural development recognized in north-central Sardinia; there structures related to the collision between continental margins that resulted in the Northern Apennines are well documented. Therefore, the Oligocene tectonics of Southwestern Sardinia also must be related to the collision event between the Southern Europe margin (i.e. a crustal sector corresponding to the future Corsica-Sardinia block) and the Adria Plate, which generated the Northern Apennines. Conversely, the previous E-W shortening- related structures must be related to Pyrenean tectonics.