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Determination of volumetric changes at an underground stone mine： a photogrammetry case study

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International Journal of mining Science and Technology 2016年第1期26卷 149-154页

作者： Slaker brent Westman Erik Ellenberger John murphy michael Virginia Polytechnic Institute and State University Blacksburg 24060 USA Office of mine Safety and Health Research NIOSH Pittsburgh PA 15236 USA

Photogrammetry, as a tool for monitoring underground mine deformation, is an alternative to traditional point measurement devices, and may be capable of accurate measurements in situations where technolo- gies such as laser scanning are unsuited, undesired, or cost-prohibitive. An underground limestone mine in Ohio is used as a test case for monitoring of structurally unstable pillars. Seven pillars were pho- tographed over in a 63 day period, punctuated by four visits. Using photogrammetry, point clouds of the mine geometry were obtained and triangulation surfaces were generated to determine volumes of change over time. Pillar spaUing in the range of 0.29-4.03 m3 of rock on individual rib faces was detected. Isolated incidents of rock expansion prior to failure, and the isolated failure of a weak shale band were also observed. much of the pillars remained unchanged during the monitoring period, which is indicative of proper alignment in the triangulated surfaces. The photographs of some ribs were of either too poor quality or had insufficient overlap, and were not included. However, photogrammetry was successfully aonlied to multiole ribs in auantifving the oillar geometrv change over time.

关键词： PhotogrammetryLimestoneUnderground miningDisplacementmonitoring

Cascadia Convergent Zone: An Example of Primary Convergent Seismogenic Structure

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Open Journal of Earthquake Research 2019年第2期8卷 132-164页

作者： Kenneth m. Cruikshank Curt D. peterson Department of Geology Portland State University Portland Oregon USA

In this article, a case is made for very-large or primary seismogenic structures in convergent margins, based on anomalous large earthquake magnitudes (mw 8 - 9) relative to rupture lengths. Out of 56,293 earthquakes (magnitudes ≥ 5) cataloged worldwide, the 10 largest events in transform, divergent, and interior settings average magnitudes of 7.3 - 7.6. But in convergent margins, the average magnitude of the 10 largest events is 8.5, roughly 32 times more energy than the other neotectonic settings. The large anomalous magnitudes of energy release in convergent margins are attributed to the transfer of inter-plate stress to the upper-plate, where convergent elastic strain is accumulated during interseismic intervals. The large volumes of rock that accumulate the elastic strain in the upper-plates of convergent zones are defined here as primary seismogenic structures. Several datasets of 1) modern upper-plate convergent strain, 2) historical earthquakes, 3) modern upper-plate vertical displacements, and 4) recent inter-plate events of Episodic Tremor and Slip (ETS) are compared to establish the extent of the primary seismogenic structure in the Cascadia convergent zone. The across-margin extents of 1) significant convergent strain, 2) margin-parallel bands of vertical displacement, 3) historical seismicity and 4) ETS events, representing inter-plate coupling and shear stress transfer to strain accumulation in the upper-plate, are used to map the width of the primary seismogenic structure. The across-margin width of the primary seismogenic structure in the central Cascadia margin ranges from 300 km in the south-central margin to 450 km in the north-central margin, as mapped landward from the buried trench. A broad source region of coseismic energy release in the Cascadia primary seismogenic structure (300 - 450 km width) could yield stronger shaking in interior metropolitan centers from a future major rupture of the mega-thrust than has been modeled from a narrow “loc

关键词： Subduction Zone Crustal Structure Seismicity Strain Deformation

Current State of Strain in the Central Cascadia margin Derived from Changes in Distance between GPS Stations

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Open Journal of Earthquake Research 2015年第1期4卷 23-36页

作者： Kenneth m. Cruikshank Curt D. peterson Department of Geology Portland State University Portland Oregon USA

Using continuously operating Global Positioning Stations in the Pacific Northwest of the United States, over 100 station-station baseline length changes were determined along seven West-East transects, two North-South transects and in three localized areas to determine both the average annual strains over the past several years, and the variation in strain over the central Cascadia convergent margin. The North-South transects (composed of multiple baselines) show shortening. Along West-East transects some baselines show shortening and others extension. The direction of the principle strains calculated for two areas 100 km from the deformation front are close to per-pendicular to the deformation front. The North-South strains are 10?8 a?1, which is an order-of-magnitude less than the West-East strains (10?7 a?1). Along several West-East transects, the magnitude of the strain increases away from the deformation front. All West-East transects showed a change in strain 250 km inland from deformation front.

关键词： Convergent margin Cascadia Strain Strain-Energy GPS

Strain Energy Release from the 2011 9.0 mw Tōhoku Earthquake, Japan

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Open Journal of Earthquake Research 2013年第4期2卷 75-83页

作者： Kenneth m. Cruikshank Curt D. peterson Department of Geology Portland State University Portland USA

The purpose of this paper is to compare the strain energy released due to elastic rebound of the crust from the tragic 2011 9.0 mwTōhoku earthquake in Japan with the observed radiated seismic energy. The strain energy was calculated by analyzing coseismic displacements of 1024 GPS stations of the Japanese GEONET network. The value of energy released from the analysis is 1.75 × 1017J, which is of the same order of magnitude as the USGS-observed radiated seismic energy of 1.9 × 1017Nm (J). The strain energy method is independent of seismic methods for determining the energy released during a large earthquake. The analysis shows that although the energy release is concentrated in the epicentral region, about 12% of the total energy was released throughout the Japanese islands at distances greater than 500 km west of the epicenter. Our results also show that outside the epicentral region, the strainenergy was concentrated along known tectonic zones throughout Japan.

关键词： Japan Earthquake Crustal Strain GPS Radiated Energy

Association of 25-hydroxy-vitamin D levels with semen and hormonal parameters

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Asian Journal of Andrology 2012年第6期14卷 855-859页

作者： Ahmad O Hammoud A Wayne meikle C matthew peterson Joseph Stanford mark Gibson Douglas T Carrell Division of Reproductive Endocrinology and Infertility University of Utah Salt Lake City UT 84108 USA Division of Endocrinology Metabolism and Diabetes Department of Internal Medicine University of Utah School of Medicine Salt Lake City UT 84108 USA ARUP Institute for Clinical and Experimental Pathology Salt Lake City UT 84108 USA Department of Preventive and Family medicine University of Utah Salt Lake City UT 84108 USA Department of Surgery (Urology) and Physiology Andrology and IVF Laboratories University of Utah Salt Lake City UT 84108 USA

Vitamin D levels have been linked to various health outcomes including reproductive disorders. The purpose of this study was to explore the association between serum vitamin D level （25-hydroxy-vitamin D, or 250HD） and semen and hormonal parameters. This is a cross-sectional study that included 170 healthy men recruited for the study of spermatogenesis from the general population. men completed general and reproductive health questionnaires, and donated blood and semen samples. The main measures were hormonal （total and free testosterone, sex hormone-binding globulin, estradiol, follicle-stimulating hormone and luteinizing hormone） and semen parameters, adjusted （n= 147） for age, body mass index （BmI）, season, alcohol intake and smoking, in relation to categories of vitamin D levels, determined apriori. The mean age of the study population was 29.0±8.5 years and mean BmI was 24.3±3.2 kg m-2. The mean 250HD was 34.1± 15.06 ng m1-1. BmI showed a negative association with 250HD. Sperm concentration, sperm progressive motility, sperm morphology, and total progressively motile sperm count were lower in men with ‘250HD ≥ 50 ng ml-1＇ when compared to men with‘20 ng ml-1 ≤ 250H D〈 50 ng ml-1,. Total sperm count and total progressive motile sperm count were lower in men with ‘250HD〈20 ng ml-1＇ when compared to men with‘20 ng ml-1≤250HD〈50 ng ml-1＇. The adjusted means of various hormonal parameters did not show statistical difference in the different categories of 250HD. In conclusion, serum vitamin D levels at high and low levels can be negatively associated with semen parameters.

关键词： low semen count obesity semen parameters vitamin D

Late Stage Interseismic Strain Interval, Cascadia Subduction Zone margin, USA and Canada

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Open Journal of Earthquake Research 2017年第1期6卷 1-34页

作者： Kenneth m. Cruikshank Curt D. peterson Department of Geology Portland State University Portland OR USA

modern horizontal strain (2006-2016) measured along 56 new and 108 previously published GPS station baselines are used to establish the length (800 km) and width (300 - 400 km) of the central Cascadia convergent margin seismogenic structure. Across-margin (west-east) annual rates of shortening range from 10﹣9 a﹣1 at the eastern (landward) limit of the central Cascadia seismogenic structure to 10﹣7 a﹣1 along the western onshore portion of the interplate zone. Relatively high shortening strain rates (10﹣8 a﹣1 to 10﹣7 a﹣1) are also measured in western transects from the northern (Explorer plate) and southern (Gorda plate) segments of the convergent margin, demonstrating that the full length of the margin (1300 km length) is currently capable of sustaining and/or initiating a major great earthquake. Vertical GPS velocities are averaged over the last decade at 321 stations to map patterns of uplift (0 - 5 mm yr﹣1) and subsidence (0 - 9 mm yr﹣1) relative to the study area mean. Along-margin belts of relative uplift and subsidence, respectively, are approximately associated with Coast Ranges and the Cascade volcanic arc. However, the vertical velocity data are locally heterogeneous, demonstrating patchy “anomalies” within the larger along-margin belts. A large coastal subsidence anomaly occurs in southwest Washington where the modern short-term trend is reversed from the long-term (~200 yr) tidal marsh record of coastal uplift since the last co-seismic subsidence event (AD1700). The modern vertical displacements represent a late stage of the current inter-seismic interval. If the horizontal strain is considered largely or fully elastic, extrapolating the modern strain rates over the last 100 years show the accumulated strains would be similar in magnitude to the observed co-seismic strains resulting from the Tōhoku, Japan, mw 9.0 earthquake in 2011. We believe that the central Cascadia seismogenic structure has accumulated sufficient elastic strain energy, during the last

关键词： Convergent margin Cascadia Strain Strain-Energy GPS

Neuromuscular,biomechanical,and energetic adjustments following repeated bouts of downhill running

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Journal of Sport and Health Science 2022年第3期11卷 319-329页

作者： Arash Khassetarash Gianluca Vernillo Renata L.Krüger W.brent Edwards Guillaume Y.millet Human Performance Laboratory Faculty of KinesiologyUniversity of CalgaryCalgary T2N 1N4Canada Department of Biomedical Sciences for Health University of MilanMilan 20133Italy Inter-university Laboratory of Human movement Biology UJM-Saint-EtienneUniversitéde LyonSaint-Etienne 42023France Institut Universitaire de France(IUF) Paris 75231France

Purpose This study used downhill running as a model to investigate the repeated bout effect(RBE)on neuromuscular performance,running biomechanics,and metabolic cost of *** Ten healthy recreational male runners performed two 30-min bouts of downhill running(DR1 and DR2)at a-20%slope and 2.8 m/s 3 weeks *** fatigue,level running biomechanics during slow and fast running,and running economy parameters were recorded immediately before and after the downhill bouts,and at 24 h,48 h,72 h,96 h,and 168 h thereafter(i.e.,follow-up days).Results An RBE was confirmed by attenuated muscle soreness and serum creatine kinase rise after DR2 compared to *** RBE was also observed in maximum voluntary contraction(mVC)force loss and voluntary activation where DR2 resulted in attenuated mVC force loss and voluntary activation immediately after the run and during follow-up *** downhill running protocol significantly influenced level running biomechanics;an RBE was observed in which center of mass excursion and,therefore,lower-extremity compliance were greater during follow-up days after DR1 compared to *** observed changes in level running biomechanics did not influence the energy cost of *** This study demonstrated evidence of adaptation in neural drive as well as biomechanical changes with the RBE after *** higher neural drive resulted in attenuated mVC force loss after the second *** can be concluded that the RBE after downhill running manifests as changes to global and central fatigue parameters and running biomechanics without substantially altering the energy cost of running.

关键词： Cost of running Eccentric exercise Fatigue muscle damage

Selective Activation of Intrinsic Cohesive Elements

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Journal of Applied mathematics and Physics 2014年第12期2卷 1061-1068页

作者： Kyeongsik Woo William m. peterson Douglas S. Cairns School of Civil Engineering Chungbuk National University Cheongju Chungbuk Korea Department of mechanical & Industrial Engineering Montana State University Bozeman MT USA

In this paper, a selective activation strategy is studied in order to alleviate the issue of added compliance in the intrinsic cohesive zone model applied to arbitrary crack propagation. This strategy proceeds by first inserting cohesive elements between bulk elements and subsequently tying the duplicated nodes across the interface using controllable multi-point constraints before the analysis begins. Then, during the analysis, a part of the multi-point constraints are selectively released, thereby reactivating the corresponding cohesive elements and allowing cracks to initiate and propagate along the bulk element boundaries. The strategy is implemented in Abaqus/Standard using a user-defined multi-point constraint subroutine. Analysis results indicate that the strategy significantly alleviates the added compliance problem and reduces the computation time.

关键词： Intrinsic CZm Arbitrary Crack Propagation Added Compliance Selective Activation multi-Point Constraint

(U-Th)/He技术约束下库车盆地北缘构造热演化——以吐孜2井为例

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地球物理学报 2014年第1期57卷 62-74页

作者：喻顺陈文吕修祥 Noreen Evans brent mcInnes 尹继元孙敬博李洁中国地质科学院地质研究所同位素热年代学实验室北京100037 大陆构造与动力学国家重点实验室北京100037 中国石油大学(北京)地球科学学院北京1022494 John De Laeter Center for Isotope Research Applied Geology/Applied PhysicsCurtin University

库车前陆盆地蕴藏着丰富的油气资源,然而盆地中新生代的构造热演化史一直缺乏有效的研究,制约了油气的勘探.本文测试了吐孜2井磷灰石、锆石(U-Th)/He年龄数据,建立了He年龄随现今温度/深度变化的关系,确定该区磷灰石(U-Th)/He体系封闭... 详细信息

库车前陆盆地蕴藏着丰富的油气资源,然而盆地中新生代的构造热演化史一直缺乏有效的研究,制约了油气的勘探.本文测试了吐孜2井磷灰石、锆石(U-Th)/He年龄数据,建立了He年龄随现今温度/深度变化的关系,确定该区磷灰石(U-Th)/He体系封闭温度为89℃.综合利用(U-Th)/He及镜质体反射率(Ro)数据模拟恢复了库车盆地吐孜2井中新生代热演化史,结果表明库车盆地吐孜洛克背斜形成起始时间约为5ma,新生代抬升剥蚀量平均约为670m,平均抬升剥蚀速率为0.133mm/a.根据新生代吐孜洛克背斜的构造演化分析确定了气源断裂活动及圈闭形成的时期,揭示了吐孜洛克背斜天然气成藏时间为5ma以后,且烃源岩生排烃、断裂活动及圈闭形成的时间具有良好的匹配关系,这是吐孜洛克油气田形成的关键因素之一.本文应用(U-Th)/He技术研究沉积盆地构造热演化史,对库车盆地油气勘探具有重要的意义.

关键词： He封闭温度构造热演化隆升剥蚀库车盆地