一种利用TM影像自动提取细小水体的方法   总被引：10，自引：1，他引：9  

杨树文  薛重生  刘涛  李轶鲲 《测绘学报》2010,39(6):611-617

提出一种利用TM影像自动提取山区细小水体的多波段谱间关系改进方法。该方法在典型谱间关系法的基础上,针对水体与阴影在蓝绿光波段亮度值降低速率差异较大的特征,基于差值运算,构建了新的多波段谱间关系水体提取模型。首先利用该模型将水体从其他地物及阴影中分离出来,然后基于数学形态学膨胀滤波算法进行空洞填充和短线连接,最后通过图像细化算法实现目标的细化。经过实验比较表明,该方法克服了许多水体提取模型只能有效提取较大面积水体的缺点,除了能够对山区的细小水体进行高精度自动提取外,还能够有效地去除阴影等干扰信息。  相似文献   

东营凹陷油- 源特征与含油气系统划分   总被引：3，自引：0，他引：3  

刘华  蒋有录  任景伦 《高校地质学报》2009,15(1):93

油源对比是含油气系统划分的基础。针对东营凹陷沙三中、沙三下和沙四上三套有效烃源岩在地球化学特征上的差异,探讨了东营凹陷内三套烃源岩与已知原油之间的空间对应关系及其成因。以油源对比为依据,将东营凹陷划分为沙三中—沙三中亚段（！）、沙三下—沙二、沙三段（！）和沙四上—沙四、沙二段（！）3个含油气系统。分析结果表明,3个含油气系统中已发现的油气藏在空间上具有明显的环状分布特征,其成因模式受控于输导要素组成、油源断层分布位置、烃源岩内砂体的发育规模以及断-砂空间组合等;其中,油源断层和砂体的空间组合关系对东营凹陷不同成因油气藏的形成与分布起主控作用。  相似文献   

Organic thermometry for chondritic parent bodies   总被引：1，自引：0，他引：1  

G.D. Cody  C.M.O'D. Alexander  H. Yabuta  A.L.D. Kilcoyne  T. Araki  H. Ade  P. Dera  M. Fogel  B. Militzer  B.O. Mysen 《Earth and Planetary Science Letters》2008,272(1-2):446-455

A unique spectroscopic feature has been identified in a study of twenty-five different samples of meteoritic insoluble organic matter (IOM) spanning multiple chemical classes, groups, and petrologic types, using carbon X-ray Absorption Near Edge Structure (XANES) spectroscopy. The intensity of this feature, a 1s − σ exciton, appears to provide a precise measure of parent body metamorphism. The intensity of this exciton is also shown to correlate well with a large negative paramagnetic shift observed through solid state ¹³C NMR. Experiments reveal that upon heating primitive IOM is transformed into material that is indistinguishable from that in thermally processed chondrites, including the development of the 1s − σ exciton. A thermo-kinetic expression is derived from the experimental data that allows the intensity of the 1s − σ exciton to be used to estimated the effective temperature integrated over time. A good correlation is observed between the intensity of the 1s − σ exciton and previously published microRaman spectral data. These data provide a self-consistent organic derived temperature scale for the purpose of calibrating Raman based thermometric expressions.  相似文献   

福建深沪湾潮间带沉积异质体及其成因初探   总被引：3，自引：0，他引：3  

俞鸣同  黄向华 《海洋科学》2003,27(12):42-44

深沪湾潮间带并列着两种性质迥异的沉积异质体——沉溺古树林和牡蛎礁。其号观性质、形成年代和沉积特征都有显著差异。古树林主要树种有：油杉(Keteleeria)、桑树(Mouas)和皂荚(Gleditisia)等，属于亚热带常绿落叶阔叶混交林，^14C测量表明其生长于7000aBP前后；牡蛎礁造礁生物主要属种有：近江重蛎(Crassostrea riwlaris)，长重蛎(Crassostrea gigas Tunbers)等。属于河口贝类，^14C测量表明其生长于20000aBP左右。地貌调查和钻孔沉积物分析显示：牡蛎礁是晚更新世古河口的产物，古树林是全新世河道古土壤生长林，两者被埋藏后近代重现海滩。  相似文献   

A texture‐based region growing algorithm for volume extraction in seismic data          下载免费PDF全文

M.G. Orozco‐del‐Castillo  M. Cárdenas‐Soto  C. Ortiz‐Alemán  C. Couder‐Castañeda  J. Urrutia‐Fucugauchi  A. Trujillo‐Alcántara 《Geophysical Prospecting》2017,65(1):97-105

We present a novel approach to automated volume extraction in seismic data and apply it to the detection of allochthonous salt bodies. Using a genetic algorithm, we determine the optimal size of volume elements that statistically, according to the U‐test, best characterize the contrast between the textures inside and outside of the salt bodies through a principal component analysis approach. This information was used to implement a seeded region growing algorithm to directly extract the bodies from the cube of seismic amplitudes. We present the resulting three‐dimensional bodies and compare our final results to those of an interpreter, showing encouraging results.  相似文献   

西秦岭党川地区花岗岩体的"解体"及同位素年龄证据   总被引：5，自引：1，他引：4  

李永军  李锁成  杨俊泉  刘静  温志亮  杨忠民 《矿物岩石地球化学通报》2005,24(2):114-120

复式花岗岩体(岩基)的“解体”是客观地质事实的反映。通过详细的岩石学特征、接触关系、形变及变质特征研究．西秦岭党川地区的花岗岩体可解体为吴砦、太碌、大堡、石门、党川、火炎山、百花7个岩体。其同位素年龄依次为174Ma、212Ma、225Ma、280Ma、391Ma、399Ma和430Ma。近年来的地质填图已经证实．各岩体间均为侵入接触关系．解体地质依据充分。岩体的解体反映了岩浆活动的特征,对进一步研究岩浆事件、成矿事件和构造演化有重要的意义。  相似文献   

应用比例边界有限元法求解狭缝对双箱水动力的影响   总被引：1，自引：1，他引：0  

滕斌  何广华  李博宁  程亮 《海洋工程》2006,24(2):29-37

比例边界有限元法(SBFEM)是一种半解析数值分析的新方法,既融合了有限元法和边界元法的优点,又有其特有的优点。用该方法可求解有限水深下狭缝对双箱水动力作用的影响,为波浪与多浮体超大型结构的相互作用探索一些规律。整个计算域划分成2个无限子域和4个有限子域,并利用加权余量法在各个子域上推导了SBFEM的积分方程;计算了4个数值算例并与边界元等其它数值方法进行了比较,验证了该方法是一种用很少单元便能得到精确结果的高效方法。应用SBFEM对不同箱体宽度、不同狭缝宽度、不同吃水深度条件的双箱作了计算,得出了狭缝对双箱水动力干涉影响的一些规律,对超大型浮体水动力分析和结构设计具有一定的参考价值。  相似文献   

海蛇乙醇浸出物对小鼠学习记忆的影响     

陈蓉  饶颖竹 《海洋科学进展》1999,(2)

本研究采用学习记忆行为训练和生化测定的方法,观察了我国４种常见海蛇的乙醇浸出物（ＡｌｃｏｈｏｌｉｃＥｘｔｒａｃｔｓｏｆＢｏｄｉｅｓｏｆＳｅａ　Ｓｎａｋｅ．ＡＥＢＳＳ）对小鼠的正常学习记忆、东莨菪碱（Ｓｃｏｐｏｌａｍｉｎｅ,Ｓｃｏｐ）所致记忆障碍、脑不同部位蛋白质含量的影响。结果表明,ＡＥＢＳＳ（剂量５００ｍｇ浸出蛋白／ｋｇ体重以上）对正常小鼠的学习记忆能力及脑内蛋白质合成有明显的促进作用;ＡＥＢＳＳ还能极显著地改善Ｓｃｏｐ所致的学习记忆障碍,使Ｓｃｏｐ组大脑皮层和小脑的蛋白质含量显著增加,海马脑区的蛋白质含量增加极显著。结果提示,ＡＥＢＳＳ对小鼠学习记忆的作用机制可能与中枢胆碱能递质系统的蛋白质合成有关。  相似文献   

Glaciopanspermia: Seeding the terrestrial planets with life?     

Joop M. Houtkooper 《Planetary and Space Science》2011,59(10):1107-1111

The question whether life originated on Earth or elsewhere in the solar system has no obvious answer, since Earth was sterilized by the Moon-forming impact and possibly also during the LHB, about 700 Ma after the formation of the solar system. Seeding by lithopanspermia has to be considered. Possible sources of life include Earth itself, Mars, Venus (if it had a more benign climate than today) and icy bodies of the solar system. The first step of lithopanspermia is the ejection of fragments of the surface into space, which requires achieving at least escape velocity. As the velocity distribution of impact ejecta falls off steeply, attention is drawn to bodies with lower escape velocities. Ceres has had, or still has, an ocean more than 100 km deep, with hydrothermal activity at its rocky core. The possible presence of life, its relative closeness to the terrestrial planets and Ceres' low escape velocity of 510 m/s suggest that Ceres could well be a parent body for life in the solar system.Icy impact ejecta - hence glaciopanspermia - from Ceres will be subject to evaporation of volatiles. Spores may be loosened by evaporation and enter the atmospheres of the terrestrial planets as micrometeorites.The seeding of the terrestrial planets from Ceres would result in (1) detection of life in the crustal layers of Ceres; (2) a commonality of Cerean life with Terran and possible Martian and Venusian life and (3) biomarkers of Cerean life, which might be found in the ice at the Moon's poles and on the surface of other main belt asteroids.  相似文献   

鲁东文登地区文登型（超单元）花岗岩体的SHRIMP锆石年代学     

王世进  万渝生  宋志勇  王伟  董春艳  张贵丽 《山东地质》2012,(2):1-5,10

文登岩体主要岩性为不同粒度的二长花岗岩,原划为三叠纪。根据新测的锆石SHRIMP U-Pb年龄为（167±3）Ma,（167±2）Ma,（157.1±1.4）Ma,结合野外接触关系改划为侏罗纪。文登花岗岩体属侏罗纪钙碱系列的侵入体,主要显示长英质陆壳深熔花岗岩的特征。推断其形成于中下地壳深度,可能来源于加厚陆壳的部分熔融,是加厚下地壳的拆沉作用的产物,而且可能标志着中国东部岩石圈减薄的开始。  相似文献