Transient deformation following the 30 January 1997 dike intrusion at Kīlauea volcano,Hawai’i     

Emily K. Desmarais  Paul Segall 《Bulletin of Volcanology》2007,69(4):353-363

On 30 January 1997 an intrusion on Kīlauea volcano opened a new fissure within the East Rift Zone (ERZ) at Nāpau Crater, 3 km uprift from the ongoing eruptions at Pu’u ’Ō’ō. The fissure eruption lasted 22 h and opened a 5.1 km long, nearly vertical dike 1.9 m, extending from the surface to a depth of 2.4 km (Owen et al. 2000b). During the eruption, the lava pond at Pu’u ’Ō’ō drained, and eruptions ceased there. Pu’u ’Ō’ō eventually refilled in late February and eruptions resumed there on 28 March 1997. Continuous GPS data show a large transient following the 30 January 1997 dike intrusion. After lengthening 40 cm during the initial eruption, the baseline between two stations spanning the ERZ lengthened an additional 10 cm over the following 6 months. A coastal station KAEP also exhibited transient deformation, as it continued to move southward (5 cm) over the same 6-month period. The baseline between two stations spanning Kīlauea’s summit caldera contracted sharply during the eruption, but gradually recovered to slightly longer than its previous length 2 months after the intrusion. We use the extended network inversion filter (McGuire and Segall 2003) to invert continuous GPS data for volume change of a spherical pressure source under Kīlauea’s summit, opening distribution on a nearly vertical dike in the ERZ and potential slip on a decollement 9 km beneath the south flank. Following the 30 January intrusion, rift extension continued below the initial dike intrusion for the duration of the transient. Decollement slip, regardless of its assumed depth, is not required to fit the data. The modeled transient summit reinflation and rift opening patterns under Nāpau crater coincide with changes in observed behavior of Pu’u ’Ō’ō’s lava pond. Rift opening accelerated while Pu’u ’Ō’ō eruptions paused and began to decelerate after the lava pond reappeared nearly a month after the Nāpau eruption. The transient deformation is interpreted as resulting from shallow accommodation of the new dike volume.  相似文献   

高耸钢筋砼结构日照变形监测与初步分析     

姜晨光  吕国栋  于绍峰  孙玲丽  黄家兴 《北京测绘》2002,(2):31-33,30

本文叙述了高耸钢筋砼结构日照变形的监测方法与监测过程，初步总结出了日照变形的基本规律。  相似文献   

楚雄盆地中—新生界构造变形特征   总被引：4，自引：1，他引：4  

曹德斌  张志斌 《云南地质》2002,21(1):50-59

根据近年笔乾研究，楚雄盆地中生代以后经历三期变形作用：早期（燕山期）主要发育于密者挤压逆冲带，显示横向置换特征，中期（喜马拉雅早期）是主变形期，西带显示由SW向NE逆冲，以叠瓦状闻和冲构造系统为其特征，晚期（喜马拉雅中晚期）发育于陡坡和深切割区，表现为重力滑动构造，这些构造期次的确定为研究该盆的发展，演化提供理论依据，亦为寻找油气资源提供靶区。  相似文献   

关于南国冰臼群成因的商榷之二   总被引：7，自引：1，他引：7  

韩同林  劳雄  郭克毅 《热带地理》2001,21(2):189-194,F003

南国冰臼群分布区大量冰川堆积、冰川条痕石及变形砾石的发现，再次有力地证明是“冰臼”不是“壶穴”的正确结论，由冰川漂砾经融冻作用形成的“石海”，与化学风化作用产生的花岗岩“石蛋”地貌特征，有天渊之别，不应混为一谈；边滩是由河流冲积物组成，不能与基岩冰床相提并论；圆滚水钻与急流旋涡及风蚀作用，形成的动力学性质、方向和方式完全不同，不该阴错阳差；节理、构造只影响冰臼的形态和发育程度，不是控制形成的动力学性质、方向和方式完全不同，不该阴错阳差；节理、构造只影响冰臼的形态和发育程度，不是控制冰臼的发育部位，不致于是非不辨，南国地区古冰川遗迹的大量发现，证明距今约二三百万年的第四纪早期确实曾发生过大规模的古冰川运动，为争论了半个多世纪的中国东部中低山区有无第四纪冰川问题，从此画上一个圆满的句号。  相似文献   

岩石变形所反映的地震作用过程--第13届国际变形机理、流变学和构造学学术会议概述   总被引：2，自引：0，他引：2  

姚大全 《国际地震动态》2001,(7):9-12

简要介绍了第13届国际变形机理、流变学和构造学学术会议的概况和特点，综述了地震变形作用的研究现状。  相似文献   

Aseismio fault slip and block deformation in North China   总被引：1，自引：0，他引：1  

Lanbo Liu  Alan T. Linde  I. Selwyn Sacks  Shihai He 《Pure and Applied Geophysics》1996,146(3-4):717-740

In North China, the tectonic fault-block system enables us to use the Discontinuous Deformation Analysis (DDA) method to simulate the long-term cross-fault survey and other geodetic data related to aseismic tectonic deformation. By the simulation we have found that: (1) Slips on faults with different orientation are generally in agreement with the ENE-WSW tectonic stress field, but the slip pattern of faulting can vary from nearly orthogonal, to pure shear along the strike of the faults, this pattern cannot be explained by simple geometric relation between the strike of the fault and the direction of the tectonic shortening. This phenomenon has been observed at many sites of cross-fault geodetic surveys, and might be caused by the interactions between different blocks and faults. (2) According to the DDA model, if the average aseismic slip rate along major active faults is at the order of several tenths of millimeter per year as observed by the cross-fault geodetic surveys, the typical strain rate inside a block is at the order of 10^–8 year^–1 or less, so that the rate of 10^–6 year^–1, as reported by observations in smaller areas, cannot be the representative deformation rate in this region. (3) Between the slips caused by regional compression and block rotation, there is a possibility that the sense of slip caused by rigid body rotation in two adjacent blocks is opposite to the slip caused by the tectonic compression. But the magnitude of slip resulting from the tectonic compression is much larger than that due to the block rotation. Thus, in general, the slip pattern on faults as a whole agrees with the sense of tectonic compression in this region. That is to say, the slip caused by regional compression dominates the entire slip budget. (4) Based on (3), some observed slips in contradiction to ENE tectonic stress field may be caused by more localized sources, and have no tectonic significance.  相似文献   

青藏块体北缘跨断层测量资料宏观分析   总被引：1，自引：1，他引：1  

赵振考  陈兵 《中国地震》1996,12(4):358-366

本文在系统整理青藏块体北缘跨断层测量资料的基础上，进行了形变类型的划分，探讨了不同类型形变所反映的断层运动性能。  相似文献   

形变,应变短临前兆标志体系的应用研究   总被引：1，自引：0，他引：1  

薄万举  吴翼麟 《华南地震》1996,16(4):28-33

文献「３」中给出了标志体系的整体框架结构和各标志的内容，本文讨论标志体系的进一步应用问题。首先讨论了异常信息合成的几种形式，然后根据标志体系的特点，给出了前兆追踪分析的方案；最后将专家系统的有关理论瑟形变应变前兆标志体系相结合，给出了一个地震预报专家系统的逻辑结构。  相似文献   

青藏高原南缘现今地球动力学研究   总被引：3，自引：1，他引：3       下载免费PDF全文

高名修 《地震地质》1996,18(2):143-155

喜马拉雅构造带于新生代时期经历了两代受力条件截然不同的形变。早期造山挤压形变与造山后的引张形变、青藏高原和高喜马拉雅的大幅度抬升。大致低喜马拉雅范围即青藏高原南缘，现今构造活动与青藏高原和高喜马拉雅块断抬升相辅相成。流行的板块聚合动力学模式，即使早新生代发生过，晚新生代以来已经灯熄。东亚大陆现代形变与地震活动的驱动力不可能源于青藏高原南缘被动挤压，而是取决于与高原隆起相关的深部主动动力学过程  相似文献   

深圳地区全,强风化花岗岩承载力探讨     

宋立峰  孔德坊 《地质灾害与环境保护》1996,7(4):41-45

对《深圳地区建筑地基基础设计规程ＳＪＧ１－８８》中全、强风化花岗岩的划分和承载力值进行讨论，将全、强风化层各划出两个亚层，同时提出了各亚层的承载力及变形模量范围值。  相似文献