素填土的自然固结特征、固结机理及其利用

工程实例的试验成果表明：素填土在自然状态下将产生固结,但这种固结除了受自身重力作用外,还受到雨水下渗、阳光照晒和风力风干等因素的影响,且上部主要受雨水下渗、阳光照晒和风力风干的影响,下部则主要受自身重力的作用。因此素填土的这种固结不是单纯的自重固结,我们称之为自然固结。试验结果还表明：经过一定时间后,在雨水下渗和阳光照晒和风力风干的作用下,上部一定深度内的素填土固结度较好,且形成“硬壳层”,填筑时间四年的素填土在6m深度内,其力学性能相当或接近于夯击能为2160kN·m的夯填土,因此可以作为对沉降敏感性要求不高的轻型低型建筑物和道路、小荷载的持力层,这既可节省工程造价,且也是安全的。     

川东北地区须家河组致密砂岩气藏异常高压成因

对川东北地区各种超压潜在成因的系统分析结果表明,欠压实作用不是异常高压成因,现今异常高压主要由天然气的充注增压(充气作用)和中燕山—喜山期的强烈构造挤压形成。利用SRK实际气体状态方程对元坝、通南巴气田充气增压贡献进行了计算:元坝气田天然气的充注增压平均为25.21MPa,平均增压幅度60.86%;通南巴气田天然气的充注增压平均为45.81 MPa,平均增压幅度72.04%。其余主要为构造挤压增压,增压幅度在元坝、通南巴气田分别为39.14%和27.96%。中燕山—喜山期构造挤压活动强度的差异控制了应力释放区的分布和储层抬升降温降压的幅度,从而控制了现今压力场平面分布特征。通南巴地区由于晚期强烈的构造挤压活动,使其现今正处于应力充分释放的泄压区,充气增压、构造挤压之后降压过程的发生是其现今超压强度较低的主要原因。     

Background deduction of the Chang’E-1 gamma-ray spectrometer data

Gamma-ray spectrometer(GRS) is used to detect the elemental abundances and distributions on the lunar surface.To derive the elemental abundances,it is vital to acquire background gamma rays except lunar gamma rays.So GRS would observe background spectra in the course of earth-moon transfer on schedule.But in fact,GRS was not switched on in the course of flying toward the moon.After the CE-1 probe finished one-year mission,GRS car-ried out a test on background data on November 21?22,2008.The authors did conduct research on the methods of background deduction using 2105 hours of usable gamma-ray spectra acquired at the 200-km orbital height by the GRS and more than 5 hours of gamma-ray spectra acquired in the GRS background test.The final research results showed that the method of deducting the background using the minimum counts in the CE-1 GRS pixels is optimal for the elements,U,K and Th.The method applies to such a case that the elemental abundances in the pixel with the minimum counting rate are 0 μg/g and the continuum background counts are constant over the Moon.Based on the method of background deduction,the full energy peak counts of U,K,and Th are calculated.     

页岩孔隙研究新进展

随着非常规油气勘探的兴起页岩孔隙研究备受重视,如何研究页岩孔隙已经成为非常规油气首要解决的问题之一,其对页岩油气勘探层位选取、资源潜力评价和油气渗流能力计算具有重要意义。对页岩微—纳米孔隙表征技术、页岩孔隙类别的划分以及页岩孔隙演化规律分别进行了综述并指出存在问题,同时结合最新研究进展对页岩孔隙研究进行展望。提出工业CT—微米CT—纳米CT/FIB系列辐射扫描方法和压汞(MICP)—氮气吸附(N2)—二氧化碳吸附(CO2)流体法是孔隙定量表征的最优方法,通过单井孔隙度测井资料与实验室测定结果建立校正图版指导储层孔隙发育段优选;页岩孔隙分类研究还应该考虑含油气性,利用原子力显微镜等工具加强孔隙含油性研究;孔隙演化规律研究应该采用模拟实验和真实剖面样品对比并结合矿物组成分析等寻找主控因素。     

Meadow saline soil changes in a marginal oasis, northwest China

This research on an alluvial plain oasis in the middle reaches of the Heihe River used the trend estimation model of principal component analysis through fixed position experiments to investigate and analyze changes in saline meadow soil characteristics after reclamation of the oasis. The conclusion is that after cultivation for a number of years, clay content increased from 9.18% (before cultivation) to 12.93% (after 30 years of cultivation) and soil nutrient content increased as well, but available potassium decreased from 1,315.50 mg/kg (before cultivation) to 240.84 mg/kg (after 30 years of cultivation). As a result of engineering, biological, and agricultural methods, total salt content significantly decreased by 97.15% from 70.28 g/kg (before cultivation) to 2.00 g/kg (after 30 years of cultivation). Through the trend estimation model of principal components analysis (PCA), it was found that soil quality improved over time. Synthetic analysis of various indexes of soil quality revealed that meadow saline soil could be used for agricultural production with responsible tillage.     

Comparisons of u ‐, g ‐, r ‐, i ‐, and z ‐band luminosity distributions between galaxy members of compact groups and isolated galaxies

To investigate the environmental dependence of u ‐, g ‐, r ‐, i ‐, and z ‐band luminosities, we perform comparative studies of luminosity distributions between galaxy members of compact groups (CGs) and isolated galaxies. It is found that for the r, i, and z bands isolated galaxies have a higher proportion of faint galaxies and a lower proportion of luminous galaxies than galaxy members of CGs, but for the u band an opposite trend is observed. The correlation between the g ‐band luminosity and the environment has different trends in different luminosity regions (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Fracturing and Failure Behavior of Carrara Marble in Quasistatic and Dynamic Brazilian Disc Tests

The tensile strength and fracturing behavior of Carrara marble subjected to the dynamic Brazilian disc test using the split Hopkinson pressure bar technique are determined and compared with those obtained by the conventional quasistatic Brazilian disc test. Detailed observation of the cracking processes is aided by high-speed video footage captured at a frame rate of 100,000 frames per second. The dynamic increase factor is computed, revealing a strong strain rate dependence of the Carrara marble when subjected to strain rates above 1 s^?1. Similar to the quasistatic loading tests, conspicuous white zones/patches commonly appear prior to the initiation of visible cracks in the dynamic loading tests. Identification of the white patch initiation and evolution is aided by image comparison software. Comparing the cracking and failure processes under quasistatic and dynamic loading, some distinct differences in the white patch geometry and initiation load are observed. In addition, the extent of the compressive failure zones around the contact points between the loading platens and specimens is found to increase with the strain rate.     

延边刺猬沟金矿Ⅰ号矿脉地质与元素地球化学特征及其找矿意义

延边刺猬沟金矿是东北地区低硫化型浅成低温热液型金矿的典型代表。为查明该矿床的矿化富集规律和深部找矿潜力,选择矿区最有工业价值的Ⅰ号主矿脉,在控矿条件和矿化蚀变特征的研究基础上,对11个成矿指示元素的相关性、浓度分带、元素组合的分带序列等地球化学特征进行系统分析。结果表明,Ⅰ号矿脉赋存于中生代陆相火山岩系中,形态、产状和规模明显受破火山口内放射状张扭性断裂（NNE向为主）控制,绿泥石化（常伴随碳酸盐化）是高品位矿段的围岩蚀变标志;不同中段的矿石（矿化岩石）中,Au除与Hg和Ag呈弱相关外,与其它元素均呈负相关,结合因子分析结果认为,本矿床中除Au外,基本没有其它伴（共）生有用组分。根据成矿相关元素的垂向变化及元素浓度分带认为,刺猬沟金矿Ⅰ号矿脉具有分段富集特征,其中220~260m和 420~450m标高为矿化富集地段。     

Incorporating neighborhood scale effects into land loss modeling using semivariograms

Journal of Geographical Systems - Scale effects are pervasive in geospatial modeling and affect the reliability of analysis results. This paper examines the neighborhood scale effects on the...     

区域气候变化下洞里萨湖表面水温时空变化的归因

基于2001—2019年洞里萨湖白天的湖泊表面水温（LSWT_day）、近地表气温（AT）、太阳辐射（SR）、地表气压（SP）、降水量（TP）、相对湿度（RH）、风速（WS）、总云量（TCC）以及水位（WL）数据,采用趋势分析、稳定性分析、持续性分析和突变分析等方法,研究了LSWT_day及各气候因素的时空分布及变化特征;利用相关性分析、回归分析和Z-Score标准化方法,厘清了各气候因素变化对LSWT_day的影响。结果表明：① 时间尺度上,区域气候以AT、WS、TCC显著升高,WL显著下降为主要特征;LSWT_day的平均升温速率为0.372℃/10a,且具有持续变暖趋势,与气候因素的突变点具有时间一致性。空间尺度上,LSWT_day和各气候因素的空间分布及变化趋势具有明显的空间异质性。其中,LSWT_day除西部湖区有微小降温外,其余湖区表现出明显的升温趋势。气候因素中,AT、SP、TP、TCC和RH的变化率大致呈现为南高值北低值的分布,而SR和WS的变化率分布为南低值北高值。② 不同时间尺度上,驱动洞里萨湖LSWT_day变化的气候因素不同。年均尺度上,LSWT_day主要受到AT、WS和WL的驱动;月均尺度上,AT变化仍是驱动LSWT_day变化的主要因素;季节尺度上,TP、WL和TCC升高为春夏LSWT_day降温的主要原因,RH是秋季LSWT_day波动的主要影响因素,冬季LSWT_day随同AT的升温而变暖。