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| 1 | Large eddy simulation of flow in a street canyon with tree planting under various atmospheric instability conditions显示文摘In this work, a large eddy simulation (LES) model, which includes momentum and heat source (or sink) inside the tree planting layer, is proposed for the simulation of flow in a street canyon with tree planting. Vegetation canopy layer simulation shows that this model can be used to simulate the velocity distribution and temperature variation inside the canopy layer. Effects of atmospheric instability on flow and pollutant distribution in a street canyon with tree planting of an aspect ratio of 0.5 are studied. Results show that compared with the canyon with no tree planting (or the exposed street canyon), the canyon with tree planting shows a reduced wind circulation and pollutant exchange rate (PER) at the top layer of the street canyon, which induces the increase in the pollutant concentrations near road surface, leeward wall and windward wall. When street canyon atmosphere is under a strongly unstable condition, wind velocity decreases while pollutant concentration is increased in the areas near the street canyon top, road surface, leeward and windward walls, compared with the wind velocity in the street canyon with the neutral stratification. When street canyon atmosphere is under a weakly unstable condition, wind velocity weakens near the street canyon top and windward wall, but strengthens near the road surface and leeward wall, and pollutant concentration is decreased near the leeward and windward walls and is increased between the two rows of trees. When the street canyon atmosphere is under an unstable condition, PER is lower than that under the neutral stratification. | GU ZhaoLin1, ZHANG YunWei2 & LEI KangBin3 1 School of Human Settlements and Civil Engineering, Xi’an Jiaotong University, Xi’an 710049, China 1 School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China 3 RIKEN Institute, Wako, Saitama, 351-0198, Japan | 2010 | Science China(Technological Sciences)2010，53，7： | 10 |
| 2 | 墨西哥湾Alaminos Canyon冷泉碳酸盐岩地质地球化学特征显示文摘墨西哥湾北部大陆坡下部深水区Alaminos Canyon冷泉碳酸盐岩结壳含有以双壳类和有孔虫为主的生物碎片,孔洞发育且常被针状文石充填.XRD分析显示结壳主要由文石组成(达98%).结壳中发育团粒、凝块和葡萄状文石等与渗漏系统微生物活动有关的沉积组构.结壳中生物碎屑的δ13C值为-4.9‰^-0.6‰,碳源主要来自海水.泥晶和亮晶文石的δ13C值为-31.3‰^-23.4‰,碳源主要来自生物降解的石油.对冷泉碳酸盐岩中生物壳体的14C测定表明冷泉活动至少持续了约10ka.碳酸盐岩结壳的酸可溶部分稀土元素总量很低(0.75~12.73μg/g),稀土元素页岩标准化配分模式具有明显的Ce负异常,表明结壳形成于氧化环境. | 冯东 陈多福 漆亮 Harry H.Roberts | 2008 | 科学通报2008，53，8： | 10 |
| 3 | A new boundary element solution to evaluate the geometric effects of the canyon site on the displacement response spectrum显示文摘This paper presents a step-by-step procedure using the three-dimensional boundary element approach to study the behavior of semi-circular canyons under seismic shear waves. The boundary element code TDASC allows utilization for various canyon geometries, evaluation of concurrent seismic waves and calculation of the ground motions on canyons due to an excitation at any arbitrary point of the incident field. Considering the widening ratio of the canyon(including prismatic, semi-prismatic and non-prismatic canyons), wave characteristics(wavelength, dimensionless period, direction) and maximum amplification pattern, the solution was applied to carry out a series of parametric studies. It was shown that canyon form can significantly affect the displacement amplification, especially at the points located on its edges. By increasing the wave dimensionless frequency(η > 1), the amplification pattern becomes more complex. On the basis of the results from a variety of considered cases, a new expression has been presented for the limiting wavelength beyond which the widening of the canyon will not have a major effect on the displacement amplification. To verify the reliability of the proposed approach, the obtained results, expressed in terms of displacement amplitude, were compared with those from the available published literature and a reasonably good agreement was observed. | Reza Tarinejad Mohsen Isari Abbasali Taghavi Ghalesari | 2019 | Earthquake Engineering and Engineering Vibration2019，18，2： | 6 |
| 4 | Physical processes causing the formation of hypoxia off the Changjiang estuary after Typhoon Chan-hom, 2015显示文摘Severe hypoxia was observed in the submarine canyon to the east of the Changjiang estuary in July 14, 2015, two days after typhoon Chan-hom. The oxygen concentration reached as low as 2.0 mg/L and occupied a water column of about 25 m. A ROMS model was con?gured to explore the underlying physical processes causing the formation of hypoxia. Chan-hom passed through the Changjiang estuary during the neap tide. The strati?cation was completely destroyed in the shallow nearshore region when typhoon passing. However, it was maintained in the deep canyon, though the surface mixed layer was largely deepened. The residual water in the deep canyon is considered to be the possible source of the later hypoxia. After Chan-hom departure, not only the low salinity plume water spread further of fshore, but also the sea surface temperature(SST) rewarmed quickly. Both changes helped strengthen the strati?cation and facilitate the formation of hypoxia. It was found that the surface heat ?ux, especially the solar short wave radiation dominated the surface re-warming, the of fshore advection of the warmer Changjiang Diluted Water(CDW) also played a role. In addition to the residual water in the deep canyon, the Taiwan Warm Current(TWC) was found to ?ow into the deep canyon pre-and soon post-Chan-hom, which was considered to be the original source of the hypoxia water. | GUO Yaru RONG Zengrui LI Bo XU Zhao LI Pixue LI Xiaodan | 2019 | Journal of Oceanology and Limnology2019，37，1： | 5 |
| 5 | Decoding the Regional~1700 Ma Deformational History from the Rocks of Big Thompson Canyon Region of Colorado Using Monazite Dating of Foliations Preserved within Garnet and Staurolite Porphyroblastic Phases显示文摘Dating of monazite grains preserved within foliations defining FIAs(foliation inflection/intersection axes preserved within porphyroblasts)have provided a detailed chronology of deformational and metamorphic events during a regional~1700 Ma orogeny,in Big Thompson region of the Colorado Rockies in the USA.FIAs controlled dating of monazite grains preserved within multiple-foliations of garnet and staurolite porphyroblast have complemented and potentially revolutionized all traditional dating approaches available.With this technique it is possible to accurately differentiate the | Afroz A Shah | 2009 | 地学前缘2009，16，S1： | 4 |
| 6 | Relation of Submarine Landslide to HydrateOccurrences in Baiyun Depression,South China Sea显示文摘Submarine landslides have been observed in the Baiyun Depression of the South China Sea. The occurrence of hydrates below these landslides indicates that these slope instabilities may be closely related to the massive release of methane. In this study, we used a simple Monte-Carlo model to determine the first-order deformation pattern of a gravitationally destabilizing slope. The results show that a stress concentration occurs due to hydrate dissociation on the nearby glide surface and on top of a gas chimney structure. Upon the dissolution of the gas hydrate, slope failure occurs due to the excess pore pressure generated by the dissociation of the gas hydrates. When gas hydrates dissociate at shallow depths, the excess pore pressure generated can be greater than the total stress acting at those points, along with the forces that resist sliding. Initially, the failure occurs at the toe of the slope, then extends to the interior. Although our investigation focused only on the contribution of hydrate decomposition to submarine landslide, this process is also affected by both the slope material properties and topography. | SUN Yunbao ZHANG Xiaohua WU Shiguo WANG Lei YANG Shengxiong | 2018 | Journal of Ocean University of China2018，17，1： | 2 |
| 7 | Stratigraphic Sequence and Sedimentary Systems in the Middle-Southern Continental Slope of the East China Sea from Seismic Reflection Data: Exploration Prospects of Gas Hydrate显示文摘Many evidences for gas hydrate bearing sediments had been found in the continental slope of the East China Sea,such as bottom simulating reflections(BSRs),undersea gas springs,pyrite associated with methane leakage,mud diapirs/mud volcanos,bottom-water methane anomalies and so on.In this study,six key stratigraphic interfaces including T_0(seafloor),T_1(LGM,23 kyr B.P.),T_2(2.58 Myr),T_3(5.33 Myr),T_4(11.02 Myr)and T_5(16.12 Myr)were identified,and then five third-order sequences of SQIII1 to SQIII5 were divided.However,T5 in southern continental slope is not found,which shows that the middle-northern Okinawa Trough had begun to rift in the early Miocene,earlier than the southern segment.Four system tracts including lowstand systems tract(LST),transgressive systems tract(TST),highstand systems tract(HST)and falling stage systems tract(FSST)are further divided.The marine erosion interface of 11.02 Myr and regressive unconformity interface of 23 kyr B.P.indicate two large-scale sea level drop events in the research area.Seven typical seismic facies identified in the continental slope are continental shelf-edge deltas,littoral fluvial-delta plains,incised channels or submarine canyons,slope fans,submarine fans or coastal sandbars,littoral-neritic finegrained sediments,mud volcanos and some other geological bodies respectively.The minimum water depth for hydrate occurrence in the Okinawa Trough is 630 m,and the thickness of gas hydrate stability zone in continental slope is between 0 and 590 m.The calculated bottom boundary of hydrate stability zone is slightly deeper than BSRs on the seismic sections.The re-depositional turbidite sand bodies,such as canyon channels,slope fans and submarine fans developed in Quaternary strata,are the predominant hydrate reservoirs.According to developing process,the dynamic accumulation of hydrate systems can be divided into three evolutionary stages including canyon erosion and hydrate stability zone migration stage,sediments destabilizing and methane leakage stage,and channel filling and hydrate re-occurrence stage. | LI Deyong CHEN Hongyan XU Shujuan XING Junhui CHENG Honggang WANG Jinkai | 2019 | Journal of Ocean University of China2019，18，6： | 1 |
| 8 | Formation of the Huajiang Grand Canyon (southwestern China) driven by the evolution of a Late Pleistocene tiankeng显示文摘Collapse is a common geomorphic process in karst areas,especially on the Yunnan-Guizhou Plateau,which has a tectonic background of integral uplift.The frequent occurrence of collapse processes in karst underground caves and canyons indicates that collapses play an important role in the formation of canyons.Through an analysis of the morphology of a semicircular cliff in the Huajiang Grand Canyon and an investigation of sediments at the bottom of the cliff,a large-scale collapse event was found to have occurred.U-series dating of secondary calcium carbonate cement in the collapse breccias indicates that collapse processes occurred approximately 200 ka.According to the geomorphological evolution of the Huajiang Grand Canyon,the following geomorphic evolutionary process is proposed:underground river-cave hall-collapse of a tiankeng-tiankeng degradation-canyon formation.These findings also show that the dating of collapsed breccia cement can be effectively used to determine the development times of karst canyons and the formation ages of tiankengs. | Yunlong Fan Andrea Columbu Kangning Xiong Guangjie Luo Song Li Xuefeng Wang Yangyang Wu | 2022 | Acta Geochimica2022，41，1： | 1 |
| 9 | 卡林型金矿床中的铊显示文摘卡林型金矿床的铊和铷的可靠数据是很少发表的。过去公认的金的指示元素是As,Sb及Hg,但在某些情况下这些元素的迁移能力和金不同,故不一定总能提供确切的潜在靶区位置,而它们大多和硫化物共生。当前,在金、银、铀、铜-钼及钼矿床中,对Tl及Tl和Rb,K,Ba,Sr的关系研究表明,高的Tl含量,低的K/Tl及Ba/Tl比值以及高的Tl/Sr比值是热液成因矿床的潜在指示。然而,直到现在为止这些关系还没扩展到卡林型矿床。本文主要内容是处理在这些矿床上取得的Tl和Rb的含量数据,验证Tl,Rb以及K之间的关系作为一种找矿方法的实用性,以及对矿化和非矿化岩石中K/Rb,K/Tl,Rb/Sr及Tl/Sr比值的数据进行比较。一些作者已经提出,K/Rb及Rb/Sr比值在确定不同矿床类型中是有用的。卡林型矿床研究包括内华达的卡林、Alligator Ridge及Jerritt Canyon矿床,犹他州的Mercur矿床及蒙大拿州的北Mocasin矿床。 | M.Ikramuddin L.Besse P.M.Nordstrom 陈国梁 | 1989 | 世界核地质科学1989，18，1： | 1 |
| 10 | Morphology and architecture of the typical erosion-genesis submarine canyons on the East China Sea slope显示文摘The Yithi submarine canyons,composed of four canyons less than 60 km in length,are located on the narrowest part of the East China Sea(ECS) slope.They extend from the shelf break at 160 m down to water depth of 1 500 m with an average gradient(along the canyon axis) of 3°(<1 000 m) and 0.7°(>1000 m).The sinuosity of the canyons ranges form 1.02 to 1.14 and their pathways extend radially from the shelf break to the axis of the Okinawa Trough.Structural and evolution pattern of the Yithi canyons are mainly controlled by sediment mass-movements and turbidity current and similar with that of the canyons in Ebro continental slope.The whole canyon system consists of three parts:the canyon,the channel and the fan.Slumps and slides often develop in the upper part of canyon where the water depth is less than 1000 m,and the turbidities usually developed on the fan.The scale of turbidites becomes smaller and their inner structures become more regular towards the ends of the canyons.Canyon-fans are often associated with small angle progradational reflection.Most canyon-fans and levees were transversely cut by active normal faults with NEE-SWW trending that are coupled to the modern extension of the Okinawa Trough.According to the age of formation of canyon-fans and sediments incised by canyons,we can infer that the Yithi canyons were formed since the middle the Medio-Pleistocene. | LIU Baohua ZHAO Yuexia LI Xishuang KAN Guangming PEI Yanliang ZHENG Yanpeng | 2009 | Acta Oceanologica Sinica2009，28，6： | 1 |
| 11 | Task 1显示文摘They say there are three ways to experience the Grand Canyon:on foot,on mules(骡子)or by air.We chose the first.Up early,my husband and I and our three children couldn't wait to get started. | 无 | 2021 | 疯狂英语(新悦读)2021，，3： | 0 |
| 12 | Evaluating the Geomorphological Features and Geotourism Potentials of Harmankaya Canyon (Bilecik, Turkey)显示文摘Harmankaya Canyon is located within boundaries of Karahasanlar settlement near Yenipazar district and Harmankoy settlement near Inhisar district in the east of the province of Bilecik. It was declared an area of nature protection under the name of 'Harmankaya Canyon Nature Park' in 2012 by the Ministry of Forestry and Water Affairs. This study introduces Harmankaya Canyon, in the first place, by discussing its geomorphological characteristics, which play a significant role in the declaration of canyon as a nature park, along with the formation. Then, it discusses the potentials born by the canyon as a newly emerging destination of geotourism. Harmankaya Canyon was created by Harmankoy Stream, one tributary of Sakarya River, within Bilecik limestones of Mesozoic age. The canyon is 2.3 km long and 650-700 m deep, with a difference of altitude of 136 m between the entrance and the exit. Having quite an impressive view, the canyon was mainly formed as a result of fluvial processes under the control of lithological, tectonic, and climatic factors together.Thanks to its geomorphological characteristics, the Harmankaya Canyon Nature Park offers both sports and social attractions, like geotourism bound by geographical formations, canyoning relying on natural sources, trekking, rock-climbing, rafting, paragliding, and photography. Considering its location close to the larger Turkish cities, such as Istanbul, Bursa, Kocaeli, and Eskisehir and accessibility, the Harmankaya Canyon Nature Park is thought to meet all criteria for a destination of day-trips and weekend excursions for a relief from urban stress or for indulging in nature. SWOT (Strengths, weaknesses, opportunities, and threats) analysis was performed to unveil the touristic potential of the canyon. As a result, it was found to pose far more strengths and opportunities than weaknesses and threats. | Levent Uncu Ebubekir Karakoca | 2019 | Journal of Tourism and Hospitality Management2019，7，1： | 0 |
| 13 | 南加州沙漠改造及去泥沙除盐工程显示文摘一、南加州沙漠改造南加州沙漠地区的地理位置主要指帝国谷(Imperial Valley)及科切拉谷(CoachellaValley)。南加州沙漠改造的一个组成部分称为顽石峡谷项目(Boulder Canyon Project),这个项目包括以上两个地区的沙漠改造。 | 胡千里 | 1987 | 全球科技经济瞭望1987，6，9： | 0 |
| 14 | A Heart-warming Countryside at Jingxi显示文摘A Comprehensive Splendor:Tongling Grand Canyon The Tongling Grand Canyon is the most famous scenic area and a must-visit attraction in Jingxi.The genesis of the canyon is like the born of a new life,which is a complex of predestination and coincidence.The place was originally a blind valley,meaning that it has a subterranean river underneath.The river on the surface looked like they suddenly disappeared from the ground.Then,due to the crustal movement,the top of the valley that covered the river collapsed and the place became an accessible sinkhole.All of these have shaped this valley into an oddly beautiful complex of landforms.Added with Guangxi’s subtropical climate,the canyon features the sceneries of the rain forest,underground river,sinkhole,waterfall,and karst cave.They are not just a combination of different attractions but a coherent scene with complementary elements. | Xie Zongming | 2022 | 中国-东盟博览2022，，3： | 0 |
| 15 | Quantitative Geomorphologic Analysis to Measure Relationships and Changes Between Morphology and Forcing Agents of the Monterey Canyon System显示文摘This research compares submarine morphology with seismic reflection profiles as they manifest tectonics in a rapidly transform continental margin (Monterey Bay,California).We study modern submarine processes integrating seismic reflection profiles interpretation,slope stability and liquefaction potential analyses and geomorphic change obtained by using high-resolution multibeam | Francesca Chiara Pascoletti Andrea Taramelli Carlo Innocenti Leonardo Disperati Ivano W.Aiello | 2009 | 地学前缘2009，16，S1： | 0 |
| 16 | 利用直接数据数值法估算San Juan盆地Morrison组Westwater Canyon段的铀资源量显示文摘最新研制的直接数据数值法被用于估算新墨西哥州San Juan盆地Morrison组Westwater Canyon段的尚未发现的铀资源量。基本地质信息取自1800个地球物理测井、40个试验井中的碎块样品和40个测量剖面的数据。利用这些数据,评价了盆地内2068个单元中每一个单元内铀富集的有利性。有利性是根据每一个单元中的地质特征与5种矿床模型的地质特征的对比相似关系而得出。每一个单元中尚未发现资源量的估算,是根据矿床类型、深度、边界品位和资源地区而分类的。 Westwater Canyon段的尚未发现铀资源量的估算值是2.6×106t U3O8,估算误差0.25×106t U3O8。估算值约两倍于美国能源部在NURE项目(铀资源评价)中所得到的数值。铀资源总量的估值是3.5×106 t U3O8,包括了已发现的资源量和尚未发现的资源量。 | R.B.McCammon W.I.Finch J.O.Kork N.J.Bridges 薛禹选 | 1989 | 世界核地质科学1989，18，1： | 0 |
| 17 | COLCA Peruvian Rivers Run Relatively Deep on Hengshan Lu显示文摘The Place Named after the unfathomably deep Colca Canyon in his native Peru-at 3,270 meters twice the depth of the Grand Canyon-chef and restaurateur Eduardo Vargas dives in for a deeper cut of his nation’s complex food culture at this colorful,sprawling spot on Hengshan Lu. | Betty Richardson | 2017 | 城市漫步(上海版、英文)2017，，9： | 0 |
| 18 | SCATTERING OF PLANE SH-WAVES ON SEMI-CANYON TOPOGRAPHY OF ARBITRARY SHAPE WITH LINGING IN ANISOTROPIC MEDIA显示文摘The purpose of this paper is to use the conforma mapping method[1]to analyzeand evaluate the ground displacement and scattering of incident SH-waves, on thesurface of semi-canyon topography of arbitrary shape with lining in anisotropic media.The problem to be solved can be reduced to the solution of an infinite algebraicequation set by using the method of full-space expansion of Fourier progression Usingthe mapping function and scattering theory to solve problems due to semi-canyon topography with lining is just like mapping the semi-cylindrical canyon of arbitraryshape into a cylindrical canyon in full-space.Moreover,it is far practical inengineering practice.From the computational examples,it is obvious that the variation of displacement amplitudes on the surface near the canyon topography is rather sharp. especially when the freqencies of incident SH-waves increase. | 韩峰 刘殿魁 | 1997 | Applied Mathematics and Mechanics(English Edition)1997，18，8： | 0 |
| 19 | 泰国高尔夫风光之旅显示文摘在很多人的心中,近邻泰国是最佳的高尔夫旅游目的地,打球费用便宜,球场水准上乘,服务一流,是值得一去再去的地方。泰国有200多座高尔夫球场,其中有很多球场都是出自世界顶尖球场设计师之手。主办过国际大赛的球场也有不少,让这些球场扬名海外。除了曼谷地区是公认的高尔夫重镇之外,桂河、华欣、芭达雅以及北部的清迈、南部的普吉岛地区,也迎来越来越多的高尔夫爱好者。本期高尔夫时间将带你一起领略泰国高尔夫球场的无限风光。 | | 2008 | 城色2008，0，11： | 0 |
| 20 | Story of a Country Road显示文摘IT took a whole year to build a 3.8-kilometer long road leading to a village,with an average progress of only ten meters per day.Such a difficult country road was built to link Abuluoha Village in Butuo County,Liangshan Yi Autonomous Prefecture of Sichuan Province,with the outside world.Deep in the Jinsha River Grand Canyon,the village of just over 250 people is surrounded by mountains on three sides and cliffs on one side.In the past,villagers left the village either by the dangerous ropeways under the mountains or on cliff-top trails that would take three hours to traverse. | | 2020 | China Today2020，69，10： | 0 |
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