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孙嘉悦  张旭晴  牛雪峰 《世界地质》2018,37(4):1265-1273
基于LiDAR点云数据进行小区域低矮植被分类方法的研究,利用渐进加密三角网算法分离地面点与低矮植被点,通过分析调整阈值对分离效果的影响验证该算法的适用程度。本文研究表明渐进加密三角网算法适用于低矮植被分布多的地势平坦地区,不适用于地形起伏较大的山区与城市地区。  相似文献   

3.
It has been generally accepted that the main trend of late Tertiary and Quaternary tectonics on Java and Sumatra is parallel to the longest axis of the islands.A study of ERTS-1 images covering parts of central and eastern Java, reveals a set of NE—SW trending lineaments, which measure a few 10 km in length. The direction of these lineaments corresponds to the so-called Meratus tectonic trend.Without being directly recognizable as fault or fault-line features these lineaments are also observable on scale 1: 50,000 aerial photographs.Geomorphic features such as unpaired terraces, linear scars, morphological unconformities, different land-use patterns across the lineament, and coastline configurations, however, strongly suggest a fault-origin of these lineaments.  相似文献   

4.
Vertical land motion caused by continuing glacial isostatic adjustment is one of several important components of sea‐level change and is not limited just to previously glaciated regions. A national‐scale analysis for the British Isles shows an ellipse of present‐day relative uplift (relative sea‐level fall), ~1.2 mm a?1, broadly centred on the deglaciated mountains of Scotland. The pattern of three foci of relative subsidence, ~1 mm a?1, results from the additional interactions of the deglacial meltwater load on the Atlantic basin and the continental shelf, and the signal due to far‐field ice sheets. At a local scale, sediment compaction can more than double the rate of relative land subsidence. Relative land‐level change (the negative of relative sea‐level change) is not the same as vertical land motion. There is a spatial pattern in the difference between relative land‐level change and vertical land motion, with differences at present of approximately ?0.1 to ?0.3 mm a?1 around the British Isles and +2.5 to ?1.5 mm a?1 globally. For the wider scientific and user community, whether or not the differences are considered significant will depend upon the location, time frame and spatial scale of the study that uses such information. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

5.
The Indian reserve of coking coal is mainly located in the Jharia coal field in Jharkhand. Although air pollution due to oxides and dioxides of carbon, nitrogen and sulphur is reported to have increased in this area due to large-scale opencast mining and coal fires, no significant study on the possible impact of coal fires on the stratospheric ozone concentration has been reported so far. The possible impact of coal fires, which have been burning for more than 90 years on the current stratospheric ozone concentration has been investigated using satellite based data obtained from Upper Atmospheric Research Satellite (UARS MLS), Earth Observing System Microwave Limb Sounder (EOS MLS) and Ozone Monitoring Instrument (OMI) in this paper. The stratospheric ozone values for the years 1992–2007, in the 28–36 km altitude range near Jharia and places to its north are found to be consistently lower than those of places lying to its south (up to a radius of 1000 km around Jharia) by 4.0–20%. This low stratospheric ozone level around Jharia is being observed and reported for the first time. However, due to lack of systematic ground-based measurements of tropospheric ozone and vertical ozone profiles at Jharia and other far off places in different directions, it is difficult to conclude strongly on the existence of a relationship between pollution from coal fires and stratospheric ozone depletion.  相似文献   

6.
Detection of changes in synthetic aperture radar (SAR) images is an important challenge due to the effects of speckle noise on these images. In recent years, appropriate methods for SAR-based-change detection have been developed based on the level set methods (LSM). These methods need to set parameters for defining a proper initial contour. Moreover, the gradient information is only employed in the total energy of these methods for segmentation of the difference image. In this study, a novel method has been proposed for unsupervised change detection of multitemporal SAR images based on the improved fast level set method (IFLSM) initialized with a combination of k-means and Otsu techniques. The proposed method utilizes the discrete wavelet transform (DWT) fusion strategy and edge enhancement to achieve a noise-resistant difference image from the mean-ratio and log-ratio images. Afterward, the generated binary change map (CM) by applying a combination of k-means and Otsu techniques on the difference image is used as the initial contour to achieve a final CM on difference image using the IFLSM. To check advantages of the proposed method, experiments are applied on two sets of multitemporal SAR images corresponding to artificial Chitgar Lake (under reconstruction) in Tehran (Iran) taken by TerraSAR-X satellite in 2011 and 2012, and corresponding to San Pablo and Briones reservoirs in California (USA) acquired by ERS-2 satellite in 2003 and 2004. Results of proposed method were compared with results of some well-known unsupervised change detection methods. Experimental results prove the sufficiency of the proposed method in unsupervised change detection in terms of accuracy, implementation time, and computational complexity.  相似文献   

7.
为实现4D(时间+空间)多目标、高精度的积雪监测,本次试验研究采用单台相机延时拍摄结合运动结构重建算法(Structure from motion,SfM),分别获取了祁连山黑河上游站裸露山坡坡面尺度单次降雪的雪深、逐日积雪空间分布和面积,以及祁连山八一冰川1.5m×1.5m的斑块尺度全年雪深及雪面特征数据。坡面尺度积雪观测研究表明:本方法可以准确获取积雪分布信息,但其雪深空间分布获取精度较差。斑块尺度雪深监测研究表明:本方法能够很好地获取连续的雪面特征信息和雪深,且获取雪深与SR50观测雪深的绝对误差小于3.4cm。在不同季节,本方法对积雪监测能力略有差异:春季快速积累期雪面纹理少,照片组对齐并获取点云数据和DEM数据的成功率较低,而冬季和消融季雪面纹理丰富,相应的对齐成功率比例和精度较高。本研究表明基于单台相机的4D摄影测量方法能够实现小范围、连续、高精度、多目标的积雪监测,未来应用前景广泛。  相似文献   

8.
Zircon is a widely-used heavy mineral in geochronological and geochemical research because it can extract important information to understand the history and genesis of rocks. Zircon has various types, and an accurate examination of zircon type is a prerequisite procedure before further analysis. Cathodoluminescence (CL) imaging is one of the most reliable ways to classify zircons. However, current CL image examination is conducted by manual work, which is time-consuming, bias-prone, and requires expertise. An automated and bias-free method for zircon classification is absent but necessary. To this end, deep convolutional neural networks (DCNNs) and transfer learning are applied in this study to classify the common types of zircons, i.e., igneous, metamorphic, and hydrothermal zircons. An atlas with over 4000 CL images of these three types of zircons is created, and three DCNNs are trained using these images. The results of this study indicate that the DCNNs can distinguish hydrothermal zircons from other zircons, as indicated by the highest accuracy of 100%. Although similar textures in igneous and metamorphic zircons pose great challenges for zircon classification, the DCNNs successfully classify 95% igneous and 92% metamorphic zircons. This study demonstrates the high accuracy of DCNNs in zircon classification and presents the great potentiality of deep learning techniques in numerous geoscientific disciplines.  相似文献   

9.

In this paper, we consider the problem of estimating the apparent slowness vector p of a plane P wave caused by a regional seismic event and recorded by a small-aperture seismic array. The case is considered when strong non-stationary and non-Gaussian random interferences act on the array sensors. In this case, the well-known estimate of wideband frequency-wave-number analysis (WFK) becomes ineffective due to large estimation errors. We have proposed three new algorithms for estimating the vector p that are robust i.e. resistant to changes in the statistical properties of the random interferences. They mainly use information about the slowness vector contained in the phases of the spectra of seismograms recorded by the array sensors. An intensive Monte Carlo simulation was carried out to compare the accuracy of the proposed phase-based estimates with the accuracy of WFK-estimate in the case when non-stationary and non-Gaussian anthropogenic interferences act on the array sensors. In the simulation we used synthetic mixtures of signals caused by a seismic event and anthropogenic seismic interferences. These signals and interferences were recorded by real small-aperture seismic arrays. It was shown that the proposed phase-based estimates of the vector p provide significantly better accuracy than traditional WFK-estimate in the case of strong anthropogenic interferences, and have approximately the same accuracy in the case of white Gaussian noise.

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10.
We present spatial distributions for pore path length and coordination number, pore throat size and nodal pore volume obtained for a 1.53 mm3 volume of 12.1% porosity Fontainebleau sandstone. The sandstone was imaged using Synchrotron X-Ray computed microtomography at 6 micron resolution. The spatial distributions were computed based upon three dimensional medial axis analysis of the void space in the image. We also present vesicle size and vesicle-vesicle contact surface area distributions for a 1.36 mm length of a 6.36 mm diameter core of basalt from a vesiculated lava flow imaged at 20 micron resolution.  相似文献   

11.
东海西湖凹陷是近海最大的盆地之一,近些年在中深层花港组储层中获得重大发现.然而,由于储层具有厚度大、非均质性强、低孔低渗、孔隙结构复杂等特征,给精细评价和甜点储层的预测带来极大困难.利用高分辨率电成像资料,在岩性和层理构造识别的基础上,将研究区储层划分成槽状交错层理细中砂岩、板状交错层理细中砂岩、槽状交错层理细砂岩、板...  相似文献   

12.
Kachishige Sato   《Tectonophysics》1993,220(1-4):69-87
We inverted 76 rates of change of baseline lengths measured with very long baseline interferometry (VLBI) during the period 1979–1989 to estimate the parameters of motions of the North American (noam) and Eurasian (eura) plates relative to the Pacific (pcfc) plate. We considered two types of plate motion models, namely, rigid and non-rigid models. In the non-rigid models, we simultaneously determined the non-rigid motions of several stations near plate boundaries due to intraplate deformation. Intraplate deformation in the regions far away from plate boundaries is assumed to be negligible.Among several models considered, a non-rigid model called M2 is found to fit most closely to the observed data. In this model, six stations are assumed to be capable of the non-rigid motion; those are goldvenu, hatcreek, mojave12, ovro 130 and vndnberg, in the southwestern United States and kashima, in Japan. M2 gives parameter sets of 0.827 ± 0.035°/m.y., about 50.5 ± 1.2°N, 78.5 ± 5.3°W and 0.889 ± 0.049°/m.y., about 59.7 ± 1.9°N, 85.1 ± 7.4 °W, representing the noam-pcfc and eura-pcfc relative motions. The plate motion parameters of M2 are nearly identical to those of the newest global-scale plate motion model nuvel-1. The noam-pcfc and eura-pcfc rotation rates of M2 respectively deviate only 0.044°/m.y. and 0.010°/m.y. from those of nuvel-1 (these deviations are only about 6% and 1%, respectively, of the rotation rates themselves). The noam-pcfc and eura-pcfc poles of M2 both lie only 2° from those of nuvel-1 (within a 2σ error ellipse of each pole). nuvel-1 is determined from spreading rates at mid-ocean ridges, azimuths of transform faults and earthquake slip vectors. Since the spreading rates are estimated from marine magnetic anomalies integrated over a geological timescale, nuvel-1 gives the plate motions averaged over this timescale. Thus, we may conclude that there is no appreciable difference between the plate motions averaged over a geological timescale (millions of years) and those in a recent short period ( ~ 10 yr).M2 also gives the horizontal non-rigid motions of VLBI stations in the southwestern United States at rates of 6–9 mm/yr and roughly in opposite direction to the rigid motion of each station associated with plate motion. hatcreek, located near the northern part of the Basin and Range Province (B&R), also shows additional westward motion of about 9 mm/yr, suggesting crustal stretching in the northern B&R. The US VLBI stations show subsidence at rates of about 5–7 mm/yr, except for goldvenu and ovro 130, whose subsidence is negligible. The Japanese VLBI station, kashima, has a horizontal non-rigid motion of about 20 mm/yr in the west-northwest direction, roughly opposite to the direction of the rigid motion. kashima also shows subsidence at a rate of about 12 mm/yr, which is larger than that deduced from geodetic data but consistent with the result from GPS.  相似文献   

13.
This is the first of a series of papers on the theme of automated pollen analysis. The automation of pollen analysis could result in numerous advantages for the reconstruction of past environments, with larger data sets made practical, objectivity and fine resolution sampling. There are also applications in apiculture and medicine. Previous work on the classification of pollen using texture measures has been successful with small numbers of pollen taxa. However, as the number of pollen taxa to be identified increases, more features may be required to achieve a successful classification. This paper describes the use of simple geometric measures to augment the texture measures. The feasibility of this new approach is tested using scanning electron microscope (SEM) images of 12 taxa of fresh pollen taken from reference material collected on Henderson Island, Polynesia. Pollen images were captured directly from a SEM connected to a PC. A threshold grey‐level was set and binary images were then generated. Pollen edges were then located and the boundaries were traced using a chain coding system. A number of simple geometric variables were calculated directly from the chain code of the pollen and a variable selection procedure was used to choose the optimal subset to be used for classification. The efficiency of these variables was tested using a leave‐one‐out classification procedure. The system successfully split the original 12 taxa sample into five sub‐samples containing no more than six pollen taxa each. The further subdivision of echinate pollen types was then attempted with a subset of four pollen taxa. A set of difference codes was constructed for a range of displacements along the chain code. From these difference codes probability variables were calculated. A variable selection procedure was again used to choose the optimal subset of probabilities that may be used for classification. The efficiency of these variables was again tested using a leave‐one‐out classification procedure. The proportion of correctly classified pollen ranged from 81% to 100% depending on the subset of variables used. The best set of variables had an overall classification rate averaging at about 95%. This is comparable with the classification rates from the earlier texture analysis work for other types of pollen. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   

14.
Two suites of plagiogranitic rocks within the oceanic crust of the Jurassic-Cretaceous ophiolitic Nicoya complex are distinguished. High level plagiogranites (HLP) crop out at the top of the cumulate sequence in the northwestern part of the Nicoya peninsula. They are associated with iron-rich dolerites and noncumulus gabbros. Based on field relationships and geochemical characteristics (e.g. enrichment in REE and HFS elements) the origin of these rocks is explained in terms of a two stage model of fractional crystallization and filter pressing. The first stage comprises the formation of tholeiitic Fe-rich melt and a highly differentiated crystal-melt mush. The second stage is characterized by filter pressing of plagiogranitic interstitial magma. Fe-dolerites form the residual rocks. Crystal fractionation of this plagiogranitic magma is due to the formation of a rather complete series of siliceous rocks.The geochemically different low level plagiogranites (LLP) are restricted to the lowest part of the cumulate ophiolitic sequence of the Lower Nicoya complex. These rocks occur as small dikes or isolated veins within cumulus gabbros. There is some evidence of strong depletion in REE and HFS elements, high silica, and low total iron in these rocks.The samples analysed probably represent a further fractionation series of acid igneous rocks in the Lower Nicoya Complex. The geochemical features and especially the association of LLP with cumulus gabbros and amphibolites may be consistent with a genetic model of partial melting of the surrounding gabbros in the hornblende stability field during a secondary thermal event, which possibly represents the formation of an intraoceanic primitive island arc between the Caribbean and the Pacific in the Upper Cretaceous. Thus the LLP and the possibly residual amphibolites are not necessarily comagmatic with regard to the remaining oceanic igneous rocks of the Lower Nicoya Complex.
Zusammenfassung Im Unteren Nicoya-Komplex, einer als jurassisch-kretazische Ozeankruste gedeuteten Ophiolith-Sequenz, treten in zwei Stockwerken intermediäre und saure Magmatite auf: Im obersten Bereich der kumulaten Sequenz kommen High Level-Plagiogranite (HLP) vor, die eng mit Fe-reichen Doleriten vergesellschaftet sind. Diese Vorkommen sind immer an Intrusionen von Gabbros gebunden. Low Level-Plagiogranite (LLP) treten an der Basis dieser Sequenz innerhalb kumulater Gabbros zusammen mit Amphiboliten auf, ohne jedoch mit Fe-Doleriten assoziiert sein.Die Genese dieser Gesteine wird an verschiedenen Modellen diskutiert, wobei die High Level-Plagiogranite auf Grund von Geländebefunden und geochemischen Merkmalen (z. B. hohe SE- und HFS-Elementkonzentrationen) durch ein zweistufiges Modell aus fraktionierter Kristallisationsdifferentiation und Filterpressung erklärt werden. Die erste Stufe beinhaltet die Entwicklung von differenzierten Fe-reichen Schmelzen in einem tholeiitischen Fraktionierungstrend. In einem späten Stadium bildet sich ein Gemisch aus Festphasen und intermediärer, plagiogranitischer Restschmelze. Die zweite Stufe beschreibt im Zusammenhang mit dem mechanischen Auspressen dieser Schmelzen in unterschiedlichen Differentiationsstadien die Entstehung separater Plagiogranitschmelzen und die Deutung der Fe-Dolerite als Residualgesteine. Durch weitere Fraktionierungsprozesse in der Plagiogranitschmelze entwickeln sich danach in einer kontinuierlichen Differentiationsreihe zunehmend saure Plagiogranite.Die Low Level-Plagiogranite weisen demgegenüber grundsätzlich verschiedene Haupt- und Spurenelementcharakteristiken auf. Sie tendieren zu höheren SiO2- und geringeren Fe-Konzentrationen. Soweit aus den wenigen bisher vorliegenden Daten hervorgeht, sind sie verglichen mit den HLP deutlich an HFS-Elementen und Seltenen Erden verarmt. Die chemische Variabilität der LLP kennzeichnet wahrscheinlich eine weitere Fraktionierungsreihe saurer Magmatite im Unteren Nicoya-Komplex mit im Laufe der Differentiation steigenden HFS- und SEE-Konzentrationen. Wenig differenzierte LLP sind im Gegensatz zu der Differentiationsreihe der HLP nicht in den analysierten Proben repräsentiert, so da\ die Interpretation ihrer Genese teilweise spekulativ bleibt. Dennoch passen der Chemismus und insbesondere das geologische Umfeld zum genetischen Modell einer Bildung saurer plagiogranitischer Schmelzen durch einen sekundären, partiellen Aufschmelzungsproze\ der umgebenden Gabbros innerhalb des Hornblende-Stabilitätsfeldes im Zuge eines weiteren Wärmeereignisses, wobei Gabbros und Amphibolite als Edukte bzw. Residualgesteine interpretiert werden könnten.Ein mögliches sekundäres Wärmeereignis kann mit der Intrusion von basischen Schmelzen in den Unteren Nicoya-Komplex bei der Bildung eines primitiven, oberkretazischen Inselbogens zwischen Pazifik und Karibik verbunden sein. Bei einer solchen Genese würden die LLP und die restitischen Amphibolite im Gegensatz zu den HLP nicht notwendigerweise als komagmatisch und damit zeitgleich zu den übrigen Magmatiten des Unteren NicoyaKomplexes gelten.

Resumen Dos series de plagiogranitos existen en el Complejo de Nicoya Inferior. Este complejo ofiolítico representa una litosfera oceánica de edad Jurásico hasta Cretácico Inferior. Plagiogranitos del nivel alto (high level plagiogranites, HLP) afloran en la parte superior de la secuencia acumulada en la peninsula de Nicoya. Están asociadas con doleritas ricas en hierro dentro de gabros intrusivos. Con respeto a la composición geoquímica y las relaciones con rocas básicas en el campo, el origen de los plagiogranitos está explicado por un modelo, que consiste de cristalización fraccionada y de filtración a presión.Plagiogranitos del nivel bajo (low level plagiogranites, LLP) aloran en la parte inferior de la secuencia acumulada en la peninsula de Santa Elena. La composición geoquímica y la asociación de estas rocas ácidas con gabros de textura acumulada y con anfibolitas coinciden con un modelo, que describe la formación de los LLP por una fusión parcial de las rocas básicas asociadas. Un evento termal, que posiblemente da lugar a una fusión parcial está representado por el origen del Complejo de Nicoya Superior, el cual se formó como arco insular primitivo en el límite intraoceánico de las placas del Caribe y del Pacífico.

— - — , . (HLP) . . , (LLP), , . , , ( .: REE HFS, ), - , , , . , . , . , , ; , . . LLP : SiO2 . , , , — HLP — HFS. HLP , LLP , . , , , . , . LLP — HLP — , - .
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15.
A method has been developed to determine ice pack rigidity and mobility using observed ice motion. Using this method, one may determine how solidly the ice pack is frozen in near real-time. In addition, spatial and temporal variations in the freezing and thawing of the ice pack can be studied. Various degrees of ice rigidity were considered using remotely-sensed ice motion off the N coast of Alaska during 1975 and 1979. Summer-time ice rigidities were detected first in late June 1975 and lasted through September 1975. However, in 1979 considerably higher rigidities were found in August while summer-like rigidities were detected into late November. Analyses of atmospheric pressure distributions suggest that less mechanical breakup occurred in the summer of 1979, resulting in the greater rigidities during August of that year. In addition, minimum ice coverage was 21% less in the Beaufort Sea in 1979 than in 1975. The result was a relatively large percent of thinner ice for November of 1979 than for 1975, the likely cause of the less rigid conditions detected during the fall of 1979.Nomenclature D deviation in height (m) of a pressure level from the standard atmosphere (Huschke 1959). - eT time lag (h) at which the autocorrelation of ice speed drops to e–1 - SL the large-scale disturbance or longwave component of a scalar field; in this study, the 500 mb circulation (Holl 1963). - U mean ice speed over a given time interval - V variance of ice speed over a given time interval  相似文献   

16.
通过热处理低品位菱锰矿矿石制备高活性纳米材料,并探究其催化去除NOx、吸附重金属性能.利用X射线荧光光谱仪、透射电子显微镜等研究菱锰矿矿石组成;利用X射线粉末衍射仪、扫描电子显微镜、比表面积分析仪、烟气分析仪、原子吸收分光光度计等研究菱锰矿矿石空气中热处理后结构变化及其NH3-SCR脱硝、重金属吸附效果.菱锰矿矿石主要组分为菱锰矿,含有少量黄铁矿、石英、白云石及硫酸盐.在空气中550℃煅烧1 h后,菱锰矿分解完全,产物以黑锰矿为主晶相,同时含有其他低结晶态锰氧化物;样品表面出现大量3~7 nm气孔,比表面积达到最大(31.5 m2/g).脱硝实验显示R550在170℃时脱硝效率可达到90%;吸附实验表明R550对Cd2+、Pb2+、Cu2+均有较好的吸附作用,表明低品位菱锰矿矿石在空气中550℃煅烧可获得高比表面积、高活性的纳米结构化材料,在环境污染物去除方面有潜在的利用价值.   相似文献   

17.
The use of UAVs finds application in a variety of fields, among which are the small scale surveys for environmental protection application. In this frame some experimental tests were carried out at Politecnico di Milano to assess metric accuracies of images acquired by UAVs and derived photogrammetric products. A block of 5 strips and 49 photos was taken by fixed wing system SenseFly, carrying a camera Canon Ixus 220HS on a rural area included in an Italian Park. Images are processed through bundle adjustment, automatic DEM extraction and orthoimages production steps with several software packages, with the aim to evaluate their characteristics, capabilities and weaknesses. The software packages tested were Erdas-LPS, EyeDEA (University of Parma), Agisoft Photoscan, Pix4UAV, PhotoModeler Scanner. For the georeferencing of the block 16 pre-signalized ground control points were surveyed in the area through GPS (NRTK survey). Comparison of results is given in terms of differences among orientation parameters and their accuracies. Moreover, comparisons among different digital surface models are evaluated. Furthermore, exterior orientation parameters, image points and ground points coordinates, obtained by the various software packages, were used as initial values in a comparative adjustment made by scientific in-house software. Paper confirms that computer vision software are faster in computation and, even if their main goal is not to pursue high accuracy in points coordinates determination, they seems to produce results comparable to those obtainable with standard photogrammetric approach. Agisoft Photoscan seems in this case to yield the best results in terms of quality of photogrammetric products.  相似文献   

18.
在系统总结TM图像上反映断裂构造"个性"的几何、运动、动力和性质特征的遥感解译方法的基础上,运用合适的遥感图像处理方法,对遥感图像构造线性体的信息进行了增强处理和提取.通过安徽南部东西向断裂构造的解译实例,发现这里的东西向断裂具有分布广和对地震、第四纪沉积及新生代盆地有重要控制作用的特点,认为它们是影响长江断裂带发育及长江形成鹅头型河流的重要原因.  相似文献   

19.
多期构造叠加使变质岩区的结构构造面貌变得十分复杂,难以研究,因此,正确地识别叠加褶皱,就成为查明变质岩区构造及变形历史的关键之一。也是建立变质岩层层序最需重视的问题,本文提出了一种基于小波变换的纹理分析。从TM图像上提取叠加褶皱信息的图像处理方法,通过对南天山东段铜花山-硫磺山地区的多次反复实践和验证,取得了野外难以获取的良好效果。  相似文献   

20.
月球的构造演化:嫦娥月图解释的理论基础   总被引:7,自引:0,他引:7  
基于月球研究资料的整理、综合及嫦娥1月图影像的实例解读和解释,本文介绍并总结了月球的构造及演化研究的若干概念、研究思路和新的观点。通过纲要性勾画,描绘月球不同类型和阶段构造演化的基本轮廓,重点论述了四个方面的问题:对月面建造历史和月球演化的历史进行了修正,将月球演化按照其特点三分为冥、古、新月宙/界,并提出建立南海纪/系的主张;以东海Hevelius抛射建造(/东海群)分析为例,主张建立构造一建造综合分析思路;从抛射建造与月面相互作用的角度,提出并阐述了掘积系统的概念、掘积系统内外带之间划分的新标志即蚀积盂及其所组成的捩侵蚀带(TSZ);在月球表面形貌构造区划分析的基础上,通过对月盆、月海的时空分布规律的分析、综合,提出月球晚期大轰击(LHB)所造成的月盆开掘期间,具有“轰击漂移”现象,并推测月球LHB过程中出现准对跖翻转;通过对古老月陆区所保存的线性构造解读和构造形迹的组合关系分析,尝试性地提出在冥月宙月球岩浆洋(LMO)演化晚期可能存在单板模式的月全球构造。月球构造演化从初始阶段的LMO所驱动的内动力体制转向冲击造成的外动力体制。  相似文献   

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