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| 1 | 鄂西黄陵背斜南部元古宙庙湾蛇绿岩的发现及其构造意义显示文摘对鄂西黄陵背斜南部宜昌太平溪、邓村一带崆岭岩群中的元古宙庙湾岩组强烈变形变质超镁铁—镁铁质岩的研究表明,镁铁质岩主要为似层状细粒斜长角闪岩,变辉长岩岩体、岩脉及辉绿岩岩脉,超镁铁质岩则主要为蛇纹石化纯橄榄岩、方辉橄榄岩,呈构造岩片、岩块分布于斜长角闪岩之中。细粒斜长角闪岩TiO2=1.14%~1.48%,稀土元素配分型式为略亏损—平坦型,无明显的Eu异常,(La/Yb)N=0.87~1.12,La/Nb、Ce/Zr、Zr/Nb、Zr/Y、Ti/Y平均值分别为1.04、0.15、18.78、2.53、290.51,Nb/Th平均为9.88,显示为大洋中脊构造环境形成的N-MORB型拉斑玄武岩;变辉长岩具典型的堆晶结构特征,稀土元素配分型式为平坦型,具明显的Eu正异常;蛇纹石化纯橄榄岩的稀土元素配分型式具中稀土元素略亏损的U形特征,显示为LREE略富集的地幔岩。上述特征表明,黄陵背斜南部崆岭岩群中的元古宙庙湾岩组实际上是一套混杂堆积的古大洋蛇绿岩残片。元古宙庙湾蛇绿岩的发现为华南扬子克拉通存在中元古代洋盆和哥伦比亚超大陆聚合、裂解构造事件提供了重要的证据。 | 彭松柏 李昌年 Kusky Timothy M 王璐 张先进 蒋幸福 熊承仁 | 2010 | 地质通报2010，29，1： | 25 |
| 2 | Zircon Hf Isotope of Yingfeng Rapakivi Granites from the Quanji Massif and ~2.7 Ga Crustal Growth显示文摘Quanji () 山岳位于西北中国,它是被解释一微大陆那由变形地下室和稳定的盖子阶层组成。在中国有在 Quanji 山岳和主要 cratons 之间的基因关系的一些争吵。在这研究,我们在 situ 锆石 U-Pb 和 Hf 获得了 Yingfeng 的同位素的作文() 从由 LA-MC-ICP-MS 的申请的西北 Quanji 山岳的 rapakivi 花岗石技术。二十个 U-Pb 年龄大小点一致或近一致,并且他们的加权的吝啬的 207Pb/206Pb 年龄是 1 个 793.9ene 大陆人更低的外壳。我们测量磁性的参数(危险性和磁性的磁滞现象参数例如浸透磁化 J s,浸透等温的残余的磁化 J rs,和内在的 coercivity H c ) 十一, Hannuoba 从太古代的 Huaian 地面降低外壳的捕虏体和九地面 granulites。结果显示一般水准珍视,太古代的 granulites 的 J s 和 J rs 是 4 122 洠条敮楴? 業敮慲潬祧愠摮瀠瑥潲潬祧;衜? 衜? | 陈能松 龚松林 夏小平 耿红燕 王璐 孙敏 Timothy M Kusky | 2013 | Journal of Earth Science2013，24，1： | 8 |
| 3 | The Neoarchean Ophiolite in the North China Craton:Early Precambrian Plate Tectonics and Scientific Debate显示文摘Archean greenstone belts and their possible inclusion of fragments of ophiolites is an im-portant research subject,since it is correlated with the nature of early oceanic crust,and can yield in-formation on the nature of early planetary lithospheres,the origin of TTG(tonalite-trondhjemite-granodiorite) continental crust,the formation of early cratons and continents,and is related to when plate tectonics started in the Earth's evolutionary history.This article briefly reviews the North China craton's Archean ophiolite argument and proposes further studies aimed at understanding the genera-tion of greenstone belts and Archean ophiolites,and suggests some key scientific questions that remain to be answered. | Timothy M Kusky 翟明国 | 2012 | Journal of Earth Science2012，23，3： | 7 |
| 4 | Granulite Facies Metamorphic Age and Tectonic Implications of BIFs from the Kongling Group in the Northern Huangling Anticline显示文摘We report preliminary results of a geochemical study on banded iron formations (BIFs) in the Zhaojiayangpo (赵家阳坡) area from the Kongling (崆岭) Group in the northern Huangling (黄陵) anticline, on the northern margin of the Yangtze craton. The CL (cathodoluminescence) images of zircons mostly have sector zoning, fir-tree zoning and patched zoning, and a few show core-rim tex tures with rims having patched zoning. The calculated formation temperatures using the Ti-in-zircon thermometer are 660-808 ℃ (714 ℃ in average), all indicating that the BIFs underwent granulite facies metamorphism. The age of zir-cons with granulite facies metamorphism is 1 990±14 Ma by LA-ICP-MS U-Pb dating, indicating that there was a significant granulite facies tectonothermal event in the northern Huangling anticline in the Paleoproterozoic, which may be related with tectonic thermal events of the metamorphism caused by the assembly of the Columbia supercontinent with South China. Moreover, the REE pattern is characterized by depletion in LREE while relatively flat in HREE, La N /Yb N =0.26, with a positive Eu anomaly (Eu/Eu*=1.59), which reveals its hydrothermal sedimentation origin and it may have formed in the environment of submarine exhalation. | 岑洋 彭松柏 Timothy M Kusky 蒋幸福 王璐 | 2012 | Journal of Earth Science2012，23，5： | 7 |
| 5 | Mapping of Planation Surfaces in the Southwest Region of Hubei Province,China——Using the DEM-Derived Painted Relief Model显示文摘Planation surfaces (PS) play a major role in reconstruction of the evolutionary history of landforms in local areas. Thus, objective and consistent mapping of planation surfaces from remotely sensed data (e.g., satellite imagery, digital elevation models (DEMs)) is paramount for interpreting the geomorphological evolution. Due to the lack of dated sedimentary covers and the difficulties of comprehensive field work, the number and age of planation surfaces in the Southwest Hubei (湖北) Province of China are still controversial. In order to map the PS in the study area, four data visualization techniques including ETM+ false color composite, grey-scale DEM, shaded relief model (SRM) and painted relief model (PRM) were examined. It is found that the PRM is the most optimal technique for planation surface mapping. The study area was successfully mapped by visual interpretation of a PRM derived from ASTER GDEM. The mapped PS was divided into five classes in terms of elevation according to previous studies, varying from 1 700-2 000 (PS1), 1 300-1 500 (PS2), 1 000-1 200 (PS3), 800-900 (PS4) to 500-600 (PS5) m. The results were partially compared with the published works. It is revealed that this method of mapping enjoys a higher accuracy and can reduce the time and effort required in the traditional mapping to a large extent. The results also demonstrated that the PRM is an effective tool for geomorphological feature mapping with considerable accuracy. The preliminary results can serve to facilitate locating rep-resentative samples for the planation surfaces dating, thus to determine the ages of PS in the study areas. | 李辉 黄徐娅 邓清禄 Timothy M Kusky 蔡晓斌 | 2012 | Journal of Earth Science2012，23，5： | 6 |
| 6 | Origin and Emplacement of Archean Ophiolites of the Central Orogenic Belt, North China Craton显示文摘Understanding Archean crustal and mantle evolution hinges upon identification and characterization of oceanic lithosphere. We report and update here more than 10 years work on a com-plete, yet dismembered and metamorphosed Archean ophiolite sequence in the North China craton, in the Dongwanzi (东湾子)-Zunhua (遵化) structural belt and correlatives in the Wutaishan (五台山) area. Banded iron formation structurally overlies several tens of meters of variably deformed pillow lavas, mafic flows, and picritic amphibolites. These are in structural contact with a 2 km thick mixed gabbro and dike complex with gabbro screens, exposed discontinuously along strike for more than 20 km. The dikes consist of metamorphosed diabase, basalt, Hb-Cpx-gabbro, and pyroxenite. The dike/gabbro complex is underlain by several kilometers of mixed isotropic and foliated gabbro, which preserve compositional layering approximately 2 km below the dike complex, and then over several hundred meters merge into strongly compositionally layered gabbro and olivine-gabbro. The layered gabbro becomes mixed with layered pyroxenite/gabbro marking a transition zone into cumulate ultramafic rocks including serpentinized dunite, pyroxenite and wehrlite, and finally into strongly deformed and serpentinized olivine and orthopyroxene-bearing ultramafic rocks interpreted as depleted mantle harzburgite tectonites. A U/Pb zircon age of 2.505 Ga from gabbro of the Dongwanzi ophiolite makes itone of the world’s oldest recognized, laterally-extensive complete ophiolite sequences, though older dismembered ophiolites are recognized in South Africa and Greenland, extending back to 3.8 Ga. This age is confirmed by a ca. 2.6 Ga Re-Os isochron from chromites from the belt, and a number of dated 2.5–2.4 Ga cross-cutting younger igneous units. The Dongwanzi ophiolite is one of the largest well-preserved greenstone belts in the central orogenic belt that divides the North China craton into eastern and western blocks. More than 1 000 other fragments of gabbro, pillow lava, sheeted dikes, harzburgite,and podiform-chromite bearing dunite occur as tectonic blocks (tens to hundreds of meters long) in a biotite-gneiss and BIF matrix, intruded by tonalite and granodiorite, in the Zunhua structural belt. Blocks in this metamorphosed Archean ophiolitic mélange preserve deeper levels of oceanic mantle than the Dongwanzi ophiolite. The ophiolite-related mélange marks a suture zone across the North China craton, traced for more than 1 600 km along the central orogenic belt. Many of the chromitite bodies are localized in dunite envelopes within harzburgite tectonite, and have characteristic nodular and orbicular chromite textures, known elsewhere only from ophiolites. The chromites have variable but high chrome numbers (Cr/(Cr+Al)=0.74–0.93) and elevated P, also characteristic of suprasubduc-tion zone ophiolites. The high chrome numbers, coupled with TiO2<0.2 wt.% and V2O5<0.1 wt.% indi-cate high degrees of partial melting from a very depleted mantle source and primitive melt for the chromite. A Re-Os isochron from the chromites indicates an age of 2.6 Ga, showing that they are the same age as the Dongwanzi ophiolite. The range in initial Os isotopic compositions in the chromites in these ophiolitic blocks is small and well within the range seen in modern ophiolites. The ultramafic and ophiolitic blocks in the Zunhua mélange are therefore interpreted as dismembered and strongly de-formed parts of the Dongwanzi ophiolite. We suggest the name 'Dongwanzi-Zunhua ophiolite belt' for these rocks. Geochemical and structural features of the Dongwanzi ophiolite suggest that it formed in a forearc environment and was incorporated in an accretionary prism soon after it formed. Neoarchean and Paleoproterozoic (2.50 and 1.90 Ga) high-pressure granulites form a belt more than 700 km long along the western side of the central orogenic belt. Several Neoarchean sedimentary basins consisting of conglomerate, greywacke, and shale are located along the eastern side of the central orogenic belt, and are interpreted as remnants of a foreland basin. The three belts record the Neoarchean subduction and collision between an arc terrane and eastern blocks of the North China craton in the Neoarchean, and further deformation and metamorphism in the Paleoproterozoic related to collisions on the northern margin of the already amalgamated North China craton. | Timothy M Kusky 李江海 | 2010 | Journal of Earth Science2010，21，5： | 5 |
| 7 | Focusing Seismic Energy along Faults through Time-Variable Rupture Modes: Wenchuan Earthquake, China显示文摘Field analysis and differential interferometry derived from Synthetic Aperture Radar (PALSAR) of the epicentral area of the May 12 2008 Mw 8.0 Wenchuan (汶川) earthquake zone reveal details about fault ruptures and ground displacements, with field-documented vertical offsets reaching 12 m along the trace of the main fault rupture, and PALSAR-measured horizontal displacements reaching 12.3 m. We document slip indicators on the fault scarp that show initially sub-horizontal then progressively steeper slip increments with time along the same fault during the 2 min earthquake, suggesting that the rupture propagated as a mixed Mode II–III fracture, with strike-slip movement at the tip directing energy from the initial rupture to points north of the epicenter, followed by vertical displacement in the interior of the slipped region. Field, seismic, and PALSAR-measured displacements are dominantly thrust near the epicentral region, and dextral in northeasterly areas, showing that slip was partitioned along the fault in space and time during the earthquake. The changing slip directions may correlate with three main pulses of energy release at 0, 23, and 57 s during the earthquake as recorded by seismograms. The earthquake generated massive landslides >100 km north of the epicenter along the trace of the fault. These massive sturzstroms formed where entire mountainsides collapsed and moved at high velocity down populated mountain valleys, jumping smaller mountains and ricocheting off steep canyon walls. These avalanches rode on cushions of water and compressed air that generated air blasts from beneath the debris, knocking down trees high on opposing mountain slopes. The concentration of massive landslides and ground deformation so far north of the epicenter was related to the Mode II–III fracture propagation focusing seismic energy along the fault towards the north, explaining why so much devastation occurred >100 km from the epicenter, such as in the destroyed city of Beichuan (北川). Understanding near-surface earthquake processes and geological hazards associated with massive earthquakes in populated mountainous areas has the potential to save many lives in the future. | Timothy M Kusky Abduwasit Ghulam 王璐 刘建国 李中全 陈骁 | 2010 | Journal of Earth Science2010，21，6： | 5 |
| 8 | Sea-Floor Metamorphism Recorded in Epidosites from the ca.1.0 Ga Miaowan Ophiolite,Huangling Anticline,China显示文摘The epidosites are interpreted to form in upflow zones at the base of ore-forming oceanic hydrothermal systems that vent as black smokers on the sea floor. This study presents new field, major and trace element, and oxygen isotope data for the recently discovered epidosites in the ca. 1.0 Ga Miaowan (庙湾) ophiolite located near the northern margin of the Yangtze craton. The epidosites occur mainly in the cores of strongly deformed, lensoidal amphibolites. Field observations, major and trace elements and oxygen isotopes suggest that the epidosites were formed by metasomatism of ocean floor basalts, diabase dykes, and gabbros during seafloor hydrothermal alteration. | 王军鹏 Timothy M Kusky Ali Polat 王璐 彭松柏 蒋幸福 邓浩 王淞杰 | 2012 | Journal of Earth Science2012，23，5： | 5 |
| 9 | Geological Features and Deformational Ages of the Basal Thrust Belt of the Miaowan Ophiolite in the Southern Huangling Anticline and Its Tectonic Implications显示文摘The stratigraphic, structural and metamorphic features of the basal thrust belt of the ca. 1.0 Ga Miaowan (庙湾) ophiolite in the southern Huangling (黄陵) anticline, show that it can be divided into three tectono-lithostratigraphic units from north to south:mélange/wildflysch rock units, flysch rock units, and sedimentary rock units of the autochthonous (in situ) stable continental margin. The three units underwent thrust-related deformation during emplacement of the Miaowan ophiolitic nappe, with kinematic indicators indicating movement from the NNE to SSW, with the metamorphic grade reaching greenschist-amphibolite facies. LA-ICP-MS U-Pb geochronology of zircons from granite pebbles in the basal thrust-related wildflysch yield ages of 859±26, 861±12 and 871±16 Ma; whereas monzonitic granite clasts yield an age of 813±14 Ma. This indicates that the formation age of the basal thrust belt is not older than 813±14 Ma, and is earlier than the earliest formation time of the majority of the Neoproterozoic Huangling granitoid intrusive complex, which did not experience penetrative ductile deformation. These results suggest that the northern margin of the Yangtze craton was involved in collisional tectonics that continued past 813 Ma.This may be related to the amalgamation of the Yangtze craton with the Rodinia supercontinent. Through comparative study of lithology, zircon geochronology, REE patterns between granodiorite and tonalite pebbles in the basal thrust-zone conglomerate, it can be concluded that the pebbles are the most similar to the Huanglingmiao (黄陵庙) rock-mass (unit), implying that they may have come from Huanglingmiao rock-mass. Zircon cores yield xenocrystic ages of 2 074±120 Ma, suggesting that the protolith of the Neoproterozoic Huangling granitoid intrusive complex may have originated from partial melting of older basement rocks, that is to say there may be Paleoproterozoic crystalline basement in the southern Huangling anticline. The ages of xenocrystic zircons in the granite pebbles in the basal-thrust conglomerate/wildflysch show a correlation with the age spectra from Australia, implying that the terrain that collided with the northern margin of the Yangtze craton and emplaced the Miaowan ophiolite at ca. 813 Ma may have been derived from the Australian segment of Rodinia. | 蒋幸福 彭松柏 Timothy M Kusky 王璐 王军鹏 邓浩 | 2012 | Journal of Earth Science2012，23，5： | 5 |
| 10 | Geological Evolution of Longhushan World Geopark in Relation to Global Tectonics显示文摘The South China fold belt has experienced a complex series of tectonic events that span 1.0 billion years of earth history. Longhushan (龙虎山) World Geopark is located on the Proterozoic suture between the Yangtze craton and Cathyasia block and highlights the long history of this belt. Collision of the Cathyasia and Yangtze cratons 1.0 billion years ago was associated with the formation of the Rodinian supercontinent where most of the planet's landmasses were amalgamated into one block. Jurassic through Early Cretaceous magmatism was associated with the inland migration of the continental margin arc associated with the penetration of a flat slab after subduction of the Kula-Farallon ridge. Slab roll-back in the Early to Middle Cretaceous opened many extensional basins across the South China fold belt, including the Xinjiang (信江) basin in which Longhushan is located, and these were filled largely with continental red beds deposited by fluvial systems in the hot torrid climate. The beds are richly fossiliferous, including remains of many dinosaurs and dinosaur eggs. Subduction of the Kula-Pacific plate in the Middle Cretaceous caused a short magmatic pulse, and then, the basins subsided slowly through the remainder of the Cretaceous. Cenozoic uplift of the red bed basins was initiated by the India-Asia collision. The uplift was associated with the formation of many faults, joints, and brittle structures that dissected the red bed deposits. Fluvial erosion of the red beds was enhanced along the brittle structures, and different locations have developed very distinctive and structurally controlled geomorphological features including mesas, kopjies, and isolated stone peaks that are known in China as Danxia (丹霞) land-forms. Together, these features form Danxia landscapes, and Longhushan World Geopark exhibits a complete range of the Danxia landscapes from juvenile, to mature and to old stages of development. The United Nations Educational, Scientific, and Cultural Organization (UNESCO) World Geopark program ensures that these features and geologic history will be preserved in their pristine state and be available for study and appreciation for generations to come. | Timothy M Kusky 叶明和 王军鹏 王璐 | 2010 | Journal of Earth Science2010，21，1： | 5 |
| 11 | Comparison of Results of Recent Seismic Profiles with Tectonic Models of the North China Craton显示文摘The geometry and timing of amalgamation of the North China craton(NCC) have been controversial,with three main models with significantly different interpretations of regional structure,geochronology,and geological relationships.The model of Zhao G C et al.suggests that the eastern and western blocks of the NCC formed separately in the Archean,and an active margin was developed on the eastern block between 2.5 and 1.85 Ga,when the two blocks collided above an east dipping subduc-tion zone.The model of Kusky et al.presumes that the eastern block rifted from an unknown larger continent at circa 2.7 Ga,and experienced a collision with an arc(perhaps attached to the western block) above a west-dipping subduction zone at 2.5 Ga,and the 1.85 Ga metamorphism is related to a collision along the northern margin of the craton when the NCC joined the Columbia supercontinent.The model of Faure et al.suggests two collisions in the central orogenic belt,at 2.1 and 1.88 Ga.Recent seismic results support both the models of Kusky et al.and Faure et al.,showing that subduction be-neath the central orogenic belt(COB) was west-directed,and that there is a second,west-dipping pa-leosubduction zone located to the east of the COB dipping beneath the western block(Ordos craton).The boundaries identified through geophysics do not correlate with the boundaries of the Trans-North China orogen suggested in the Zhao et al.model,and the subduction polarity is opposite that predicted by that model.The seismic profiles are consistent with an Archean collision above a west-dipping sub-duction zone beneath the COB predicted by the models of Kusky et al.,and the second west-dipping subduction zone is consistent with the two events suggested in the Faure et al.model. | Timothy M Kusky | 2011 | Journal of Earth Science2011，22，2： | 4 |
| 12 | Discovery of a Sheeted Dike Complex in the Northern Yangtze Craton and Its Implications for Craton Evolution显示文摘The Miaowan (庙湾) ophiolite is a highly dismembered ophiolitic complex cropping out near the northern margin of the Yangtze craton. The rocks of this complex consist of, from bottom to top, harzburgite tectonite locally containing podiform chromite, dunite, layered and isotropic gabbro, a sheeted dike complex (SDC), meta-pillow lavas with chert pods and layers, and tectonically intercalated marble. The SDC is a very important and significant part of the Miaowan ophiolitic sequence, and grades downward into gabbro and ultramafic rocks, and upward into meta-pillow lavas. Some dikes preserve one-way chilled margins, typical of extensional ophiolitic settings, whereas most preserve double chilled margins, in cases where the chilling direction can be determined. The SDC is mainly com-posed of meta-diabase (dolerite), meta-plagiogranite , and small amounts of meta-gabbro and ultramafic rocks. LA-ICP-MS zircon dating yields an upper intercept age of 1 026±79 Ma for one meta-plagiogranite, 1 043±23 Ma for a second meta-plagiogranite and 1 096±32 Ma for one meta-gabbro at the bottom of the SDC, suggesting formation of the SDC at circa 1 026-1 096 Ma, consistent with the recently determined formation age of the Miaowan ophiolite. Sparse geochemical data on the meta-diabase indicate that the protolith was a sub-alkaline, low-potassium tholeiite similar to mid-ocean ridge basalt (MORB). The chondrite-normalized rare earth element (REE) patterns of the meta-diabase are generally flat ((La/Yb) N =0.56-0.94), with a slight depletion in LREE, but no obvious Eu anomalies. Given that the meta-plagiogranites show evidence of formation in a suprasubduction zone environment, we suggest that the basalts were originally island arc tholeiites, perhaps formed in an extensional forearc setting. The geochemistry of the meta-diabase and plagiogranite from the sheeted dikes, together with regional relationships, all agree with the previous interpretations that the Miaowan ophiolite formed in a suprasubduction zone setting. | 邓浩 Timothy M Kusky 王璐 彭松柏 蒋幸福 王军鹏 王淞杰 | 2012 | Journal of Earth Science2012，23，5： | 3 |
| 13 | Structural and Tectonic Evolution of El-Faiyum Depression,North Western Desert,Egypt Based on Analysis of Landsat ETM+,and SRTM Data显示文摘False color Landsat ETM+ (bands 7, 4, 2 in RGB) and SRTM images of the El-Faiyum depression, Egypt, highlights major NE-SW faults and other lineaments trending NW-SE and N-S. Airborne magnetic data reveal some E-W subsurface faults which are not recognized on Landsat ETM+ and SRTM images. Ratio images (5/7, 3/1, 4/3) and (5/7, 5/1, 4) were used for lithological discrimination of different rock types. The El-Faiyum area is occupied by sedimentary rocks of Middle Eocene, Upper Eocene, Oligocene, Lower Miocene, Pliocene, Pleistocene and Holocene. Understanding the structural regime of El-Faiyum depression in the Western Desert of Egypt is significant in relation to the neotectonics of the Nile Delta and to the development of new communities west of the delta. The area is covered by Late Cretaceous, Middle to Late Eocene deposits, Oligocene deposits (comprising fluviatile sediments and basalt sheets) and Pliocene and Quaternary alluvium and sand deposits. New geological and structural maps were prepared at a scale of 1 : 100 000 using Landsat ETM+ and SRTM images coupled with extensive field work. The major structural trends are E-W, ENE, NS and NW-the same trends observed elsewhere in North Africa from NW Sudan to NE Egypt including north and central Sinai. El-Faiyum depression is a structurally-controlled tectonic basin, marked by northeast-striking faults along its northern margin. These faults are parallel to similar faults of the Syrian arc fold belt, which includes a group of related faults, folds, push-up structures, and basins. Qarun Lake is located in the northern part of El-Faiyum depression, at a right-step between two strands of the NE striking fault system. We have suggested elsewhere that El-Faiyum depression is a pull-apart basin related to extension between these mismatched strands of strike-slip faults. The E-W structures are probably related to the relative motion between south Europe and north Egypt and closure of the Neotethys. The continuation of these faults in the present area is only detected from magnetic and seismic studies. The question that needs to be raised is why these old structural features have been reactivated in recent times. Thus, the presence of these fault zones must be heeded in all development plans for El-Faiyum region. | Timothy M Kusky Talaat M Ramadan Mahmoud M Hassaan Safwat Gabr | 2011 | Journal of Earth Science2011，22，1： | 3 |
| 14 | Environmental Monitoring of Bombetoka Bay and the Betsiboka Estuary,Madagascar,Using Multi-temporal Satellite Data显示文摘The causes and consequences of soil erosion in Madagascar have been the focus of recent environmental debates.The Betsiboka,Madagascar's largest river stretching 600 km from the high central plateau to the northwest coast on the Mozambique Channel,is a major conduit for transporting lateritic soils and sediments derived from the highlands of Central Madagascar to the sea.These entrained lateritic sediments color the river a blood-red hue,as if the life of the island is being drained away.In this study,Landsat visible and near infrared spectral bands are used to map the underwater sediments especially under the sea and in the interface between seawater and freshwater.Band color composites,single bands and band ratios are used to improve the detection of underwater sediments including sand bars and delta lobes.We show the evolution of the bay,coastline,delta,and change detection results derived from Landsat satellite images recorded in 1973,1989,1999,2000 and 2003,respectively.Results indicate that sedimentary transport and suspension in Bombetoka Bay has significantly changed during the past 30 years,with a dramatic increase in the amount of sediment moved by the river,and deposited in the estuary and in offshore delta lobes.These changes have adversely affected agriculture,fisheries,and transportation for one of Madagascar's largest ports.The changes are attributed to increased erosion following large-scale deforestation,bush fires,and overgrazing in the river basin. | Tsilavo Raharimahefa Timothy M Kusky | 2010 | Journal of Earth Science2010，21，2： | 2 |
| 15 | Structural controls on Neoprotero zoic mineralization in the South Eastern Desert, Egypt: an integrated field, Landsat-TM, and SIR-C/X SAR approach显示文摘 | Timothy M Kusky Talaat M Ramdadan | 2002 | Journal of African Earth Sciences2002，35，： | 1 |
| 16 | New Research Progress on the Pre-Sinian Tectonic Evolution and Neotectonics of the Huangling Anticline Region,South China显示文摘In this paper the authors briefly introduce and review the new progress of the newly dis- covered Proterozoic Miaowan (庙湾) ophiolite and Neoproterozoic Huangling (黄陵) granitoids in the southern Huangling anticline in the Yangtze craton, and the tectonic evolution significance of assemblage and breakup of Rodinia and Columbia supercontinent in South China. | 彭松柏 Timothy M Kusky 周汉文 王璐 项伟 | 2012 | Journal of Earth Science2012，23，5： | 1 |
| 17 | Structural controls on Neoprotero zoic mine realization in the South Eastem Desert,Egypt:An integrated field,Landsat-ETM,and SIR-C/X SAR approach显示文摘 | Timothy M Kusky Talaat M Ramdadan | 2002 | Journal of African Earth Sciences2002，，35： | 1 |
| 18 | Ramdadan Structural controls on Neoprotero zoic mineralization in the South Eastern Desert, Egypt:an integrated field, Landsat TM, and SIR-C/XSAT approach 显示文摘 | Timothy M Kusky T M | 2002 | Journal of African Earth Sciences2002，，35： | 1 |
| 19 | Lithospheric Structure in the North China Craton Constrained from Gravity Field Model(EGM 2008)显示文摘A detailed knowledge of the thickness of the lithosphere in the North China craton(NCC) is important for understanding the significant tectonic reactivation of the craton in Mesozoic and Ce-nozoic.We achieve this goal by applying the newly proposed continuous wavelet transform theory to the Gravity Field Model(EGM 2008) data in the region.Distinct structural variations are identified in the scalogram image of profile Alxa-Datong(大同)-Qingdao(青岛)-Yellow Sea(profile ABC),trans-versing the main units of NCC,which we interpret as mainly representing the Moho and lithosphere-asthenosphere boundary(LAB) undulations.The imaged LAB is as shallow as 60-70 km in the south-east basin and coastal areas and deepens to no more than 140 km in the northwest mountain ranges and continental interior.A rapid change of about 30 km in the LAB depth was detected at around the boundary between the Bohai(渤海) Bay basin(BBB) and the Taihang(太行) Mountains(TM),roughly coincident with the distinct gravity decrease of more than 100 mGal that marks the North-South Grav-ity Lineament(NSGL) in the region.At last we present the gravity modeling work based on the spectral analysis results,incorporating with the observations on high-resolution seismic images and surface to-pography.The observed structural differences between the eastern and western NCC are likely associ-ated with different lithospheric tectonics across the NSGL.Combined with seismic tomography results and geochemical and petrological data,this sug-gests that complex modification of the litho-sphere probably accompanied significant litho-spheric thinning during the tectonic reactivation of the old craton. | 李媛媛 杨宇山 Timothy M Kusky | 2011 | Journal of Earth Science2011，22，2： | 1 |
| 20 | Late Paleozoic volcanic record of the Northern Junggar Terrane, Xinjiang, northwestern China: Major and trace element characteristics, Sr-Nd isotopic systematica and implications for tectonic evolution显示文摘 | Zhang Zhaochong Zhou Gang Kusky Timothy M | 2009 | Gondwana Research2009，16，2： | 1 |
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