港东油田二区一断块高分辨率层序地层

高分辨率层序地层为建立高分辨的年代地层格架提供了一种有效的方法。港东油田二区一断块的储油层段主要为明化镇组下段曲流河沉积 ,通过运用沉积基准面原理对研究区内岩芯、测井资料的综合分析 ,识别出了曲流河沉积短期、中期地层旋回及其特征 ,短期地层旋回可能主要为河流作用形成的自旋回 ,无法确定与基准面变化的关系 ;中期地层旋回则完全是由沉积基准面变化形成 ,由不同类型的短期地层旋回构成 ,并发现不同的短期旋回出现在中期基准面旋回的不同位置 ,相同的微相在中期基准面旋回的不同位置具有不同的结构特征 ,弄清了中期基准面对作为主要储层的河道砂体的侧向连通性和内部非均质性的控制作用。根据这些特征 ,建立了工区二维高分辨率地层对比格架 ,并在此基础上对工区的储层分隔间进行了预测     

现代地质工作重要发展领域:“十一五”期间勘查地球化学评述

"十一五"期间(2006—2010年),国土资源部中国地质调查局继续推进区域化探与多目标区域地球化学调查计划。在区域化探方面,完成调查面积82.93万km2(累计完成756.62万km2),发现异常4 708处,经验证发现各类矿产411处,其中有色金属矿产273处,占66.4%,取得重大找矿突破。开展矿产资源地球化学评价,通过建立典型矿床地球化学异常模式,来圈定找矿靶区和进行资源潜力定量预测。在多目标区域地球化学调查方面,完成调查面积26.56万km2(累积完成165.66万km2),建立生态地球化学评价体系,主要针对重金属元素成因来源、迁移转化、生态效应与变化趋势进行较为全面和深入的研究。土地质量地球化学评价表明,中国土地达到优质级占53%,优良级占33%,较差等级主要分布在中东部经济社会发达地区。土壤有机碳研究表明,全国表层土壤(0～0.2m)平均碳密度仅为3 186t/km2,且各地区碳密度变化幅度较大,说明中国土壤有机碳处于低水平和不稳定状态。"十一五"期间勘查地球化学针对重大资源与环境问题,深化和延拓地质工作内涵,逐步形成矿产资源评价、生态地质科学研究、土地质量与生态评价、全球变化科学研究及基础地学研究等现代地质工作若干重要发展领域。     

潜热释放和初始位温扰动对锋生的影响

在Chan和Cho作的基础上,用中α尺度位温扰动代替了原来的中β尺度位温扰动,并且增加了一个高度函数H（Z）,模式还改变了相对湿度的分布,取了可供比较的两个试验,并运行了半地转湿大气锋生模式程序,积分一段时间后,绘出有关的物理量的等值线图,分析、比较了非绝热加热及初始位温扰动对物理量的影响。 试验结果表明:初始位温扰动为中α尺度比中β尺度更接近实际情况,对流层湿度分布不均匀,非绝热加热的作用比初始位温扰动的影响明显些。     

Observations of Alfvén Ionospheric Resonances on the Earth's Surface

The paper briefly reviews the preliminary results of observations of Alfvén ionospheric resonances performed in the northern Carpathian Mountains (south-eastern Poland) by the Cracow Schumann Resonances Group. The results confirm the simple models proposed recently by Lysak and Sentman.     

Adjacency selection in Markov Random Fields for high spatial resolution hyperspectral data

 Markov Random Fields, implemented for the analysis of remote sensing images, capture the natural spatial dependence between band wavelengths taken at each pixel, through a suitable adjacency relationship between pixels, to be defined a priori. In most cases several adjacency definitions seem viable and a model selection problem arises. A BIC-penalized Pseudo-Likelihood criterion is suggested which combines good distributional properties and computational feasibility for analysis of high spatial resolution hyperspectral images. Its performance is compared with that of the BIC-penalized Likelihood criterion for detecting spatial structures in a high spatial resolution hyperspectral image for the Lamar area in Yellowstone National Park. Received: 9 March 2001 / Accepted: 2 August 2001     

潮汐河口坝田长宽比对泥沙淤积特征影响试验研究

在航道治理工程中,往往通过丁坝群来实现其稳定航槽等目的,而坝田作为缓流区,其与主槽的水沙交换主要取决于横向的紊动交换。基于长江口北槽丁坝群实测资料分析和物理模型水槽试验研究发现不同长宽比坝田内的流态、淤积形态、坝田与相邻河段水沙交换的机理均不同,在长江口北槽丁坝群坝田建成后的淤积初期阶段,长宽比为0.30～0.40的坝田内的平均淤积强度最大。水槽试验研究表明,长宽比为0.50的坝田内淤积的主要部位即为主环流所在位置(坝田外侧),而在副环流位置,则出现微淤或冲刷的趋势;而长宽比为0.33的坝田内的淤积分布相对比较均匀。长宽比为0.33的坝田内淤积速率明显大于长宽比为0.50的坝田,长宽比为0.33的坝田达到冲淤平衡的时间较长。坝田淤积强度与随坝田回流强度、坝田与主槽水沙交换系数的增加而增加。     

The effect of aquifer heterogeneity on natural attenuation rate of BTEX

Monitored natural attenuation can be a viable option for remediation of groundwater contamination by BTEX compounds. Under the field conditions, the rate of contaminant mass attenuation through natural processes, such as biodegradation, to a large extent affected by the groundwater flow regime, which is primarily controlled by the aquifer heterogeneity. Numerical simulation techniques were used to describe quantitatively the relationship between biodegradation rate of BTEX and aquifer heterogeneity. Different levels of aquifer heterogeneity were described by random hydraulic conductivity fields (K) having different statistical parameters, the coefficient of variation (CV) and the correlation length (h). The Turning Bands Algorithm was used to generate such K fields. Visual MODFLOW/RT3D was used to simulate the fate and transport of dissolved BTEX plume within heterogeneous aquifers. The multispecies reactive transport approach described BTEX degradation using multiple terminal electron-accepting processes. First-order biodegradation rate constants were calculated from simulated BTEX plumes in heterogeneous flow fields. The results showed that aquifer heterogeneity significantly affected biodegradation rate; it decreased with increasing CV when h was in the range of up to 12 m, whereas it increased with increasing CV when h was greater than about 12 m. For well characterized aquifers, this finding could be of great value in assessing the effectiveness of natural attenuation during feasibility studies at BTEX contaminated sites.     

Spectral-spatial classification of hyperspectral images using wavelet transform and hidden Markov random fields

This paper proposes a spectral–spatial method for classification of hyperspectral images. The proposed method, called SSC, consists of two steps. In the first step, to overcome the computation complexity, a wavelet-based classifier is designed. In the second step, to enhance the classification accuracy, a novel hidden Markov random field called NHMRF technique in spatial domain is suggested. In NHMRF, we convert two-dimensional energies of traditional hidden Markov random field to three-dimensional energies and then we apply edge preserving regularization terms on each two-dimensional energy of this cube. The class label of each test pixel is fixed based on minimum three-dimensional energy achieved by edge preserving regularization terms. Experimental results show that the classification accuracy of the proposed approach based on three-dimensional energies and edge preserving regularization terms is effectively improved in comparison with the state-of-the-art methods.     

Chanchu台风(0601)流出层的低理查森数特征分析

对流层高层存在流出层是台风环流结构的一个典型特征,但是关于台风流出层层结及不稳定特征的分析相对较少。本文利用了非静力中尺度WRF模式输出的0601号Chanchu台风的模式模拟资料,以Ri(理查森数) < 1为判据,分析了存在于Chanchu台风流出层的低理查森数,以及它的分布特征与形成原因。分析表明,在Chanchu台风流出层10~16 km高度附近,低理查森数出现频率较大,甚至达到湍流标准,这与Emmanuel(2011) 推测得出的结论一致。通过对比台风发展过程发生、发展、成熟和消亡阶段流出层低理查森数的状况,发现低理查森数的出现频率与Chanchu台风强度有较好的对应关系,即Chanchu台风强度越强,低理查森数出现的频率越高,范围也越大,同时,Chanchu流出层的低理查森数的存在及分布特征受到水平风的垂直切变和稳定度影响。在Chanchu台风强度缓变过程中,低理查森数的分布还存在日变化,这与太阳辐射日变化导致的辐射加热和冷却造成的稳定度变化有关。分析揭示出存在于Chanchu台风流出层的低理查森数层的结构特征,也验证了低理查森数层对Chanchu台风的强度和辐射日变化具有敏感性。