印尼贯穿流源区马鲁古海和哈马黑拉海水团来源的气候态分析

本文利用World Ocean Atlas 2013（WOA2013）气候态的温盐资料和the Simple Ocean Data Assimilation （SODA v3.3.1）流场数据，分析印尼贯穿流东部源区马鲁古海和哈马黑拉海的水团垂向分布特征及其来源，特别是次表层、中层及深层水的来源和路径。结果表明，气候态下，马鲁古海次表层的高温高盐水来自于北太平洋，与北太平洋热带水性质接近，哈马黑拉海次表层主要是来自南太平洋热带水；中层水以低温低盐为特征，马鲁古海的中层水来自南太平洋，受南极中层水控制，哈马黑拉海的中层水可能是从马鲁古海而来的南太平洋水；对于次表层和中层之间的过渡层，马鲁古海与哈马黑拉海的水源为南、北太平洋的混合水，且两个海域之间也存在着水团交换；在深层，马鲁古海的水源更倾向于班达海北部及塞兰海，而与太平洋水无关，哈马黑拉海由于地形阻挡也难以与太平洋直接发生水团交换。     

Spatial variations of throughfall through secondary succession of evergreen broad‐leaved forests in eastern China

Linking spatial variations of throughfall with shifting patterns during forest succession is important for understanding developmental patterns of ecosystem function. However, no such approach has been previously used for the chronosequence of evergreen broad‐leaved forests in subtropical regions. This study was conducted in a chronosequence of secondary forest succession in Tiantong National Forest Park, to determine the optimum number of collectors within certain limits of error. Throughfall was 66, 55 and 77% of gross precipitation in an early‐succession (SS), sub‐climax (SE) and climax (CE) forest, respectively. The coefficient of variations (CV) of throughfall reduced with increasing rainfall amounts. Monte Carlo resampling approach was used to find mean values and 90 and 95% confidence intervals of a variable number of collectors (n) ranging from 2 to 24. During the study period, with nine collectors at SS, five at SE and five at CE, the error in the mean individual throughfall did not exceed 10%, respectively. This error was reduced to 5% when using 16, 10 and 10 collectors at SS, SE and CE, respectively. The CVs decreased greatly with increasing sample size when the sample size was less than 16 for the three successional stages, regardless of rainfall amounts. Based on the Student's t‐value analysis of the mean individual throughfall volumes, a sample size of 16 at SS, five at SE and four at CE would be enough for throughfall estimates at an accepted error of 10% of 95% confidence level, respectively. Therefore, we concluded that the 25 of collectors used in the present study were sufficient to estimate the throughfall value at an accepted error of 10% at 90 and 95% confidence levels, even for those small rainfalls in eastern China. Copyright © 2011 John Wiley & Sons, Ltd.     

A new approach of dynamic monitoring of 5‐day snow cover extent and snow depth based on MODIS and AMSR‐E data from Northern Xinjiang region

Taking the Northern Xinjiang region as an example, we develop a snow depth model by using the Advanced Microwave Scanning Radiometer‐Earth Observing System (AMSR‐E) horizontal and vertical polarization brightness temperature difference data of 18 and 36 GHz bands and in situ snow depth measurements from 20 climatic stations during the snow seasons November–March) of 2002–2005. This article proposes a method to produce new 5‐day snow cover and snow depth images, using Terra and Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) daily snow cover products and AMSR‐E snow water equivalent and daily brightness temperature products. The results indicate that (1) the brightness temperature difference (Tb_18h–Tb_36h) provides the most accurate and precise prediction of snow depth; (2) the snow, land and overall classification accuracies of the new images are separately 89.2%, 77.7% and 87.2% and are much better than those of AMSR‐E or MODIS products (in all weather conditions) alone; (3) the snow classification accuracy increases as snow depth increases; and (4) snow accuracies for different land cover types vary as 88%, 92.3%, 79.7% and 80.1% for cropland, grassland, shrub, and urban and built‐up, respectively. We conclude that the new 5‐day snow cover–snow depth images can provide both accurate cloud‐free snow cover extent and the snow depth dynamics, which would lay a scientific basis for water management and prevention of snow‐related disasters in this dry and cold pastoral area. After validations of the algorithms over other regions with different snow and climate conditions, this method would also be used for monitoring snow cover and snow depth elsewhere in the world. Copyright © 2011 John Wiley & Sons, Ltd.     

Maohokite,a post‐spinel polymorph of MgFe2O4 in shocked gneiss from the Xiuyan crater in China

Maohokite, a post‐spinel polymorph of MgFe₂O₄, was found in shocked gneiss from the Xiuyan crater in China. Maohokite in shocked gneiss coexists with diamond, reidite, TiO₂‐II, as well as diaplectic glasses of quartz and feldspar. Maohokite occurs as nano‐sized crystallites. The empirical formula is (Mg_0.62Fe_0.35Mn_0.03)²⁺Fe³⁺₂O₄. In situ synchrotron X‐ray microdiffraction established maohokite to be orthorhombic with the CaFe₂O₄‐type structure. The cell parameters are a = 8.907 (1) Å, b = 9.937(8) Å, c = 2.981(1) Å; V = 263.8 (3) ų; space group Pnma. The calculated density of maohokite is 5.33 g cm^?3. Maohokite was formed from subsolidus decomposition of ankerite Ca(Fe²⁺,Mg)(CO₃)₂ via a self‐oxidation‐reduction reaction at impact pressure and temperature of 25–45 GPa and 800–900 °C. The formation of maohokite provides a unique example for decomposition of Fe‐Mg carbonate under shock‐induced high pressure and high temperature. The mineral and its name have been approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association (IMA 2017‐047). The mineral was named maohokite after Hokwang Mao, a staff scientist at the Geophysical Laboratory, Carnegie Institution of Washington, for his great contribution to high pressure research.     

哈尔滨黄土的粒度与地球化学特征及其对粉尘物源的指示

哈尔滨黄土位于欧亚黄土带的最东端，对它的风尘物源研究是深层次理解风尘堆积与区域构造-地貌-气候变化耦合关系的关键。然而，对哈尔滨黄土地球化学组成的研究尚未开展，对其性质还存在认识上的不统一。为此，我们研究了哈尔滨天恒山剖面L₁黄土层的粒度和地球化学组成，并对其化学风化和物源等展开讨论。为了示踪哈尔滨黄土的物源，我们还对东北沙地（浑善达克沙地、科尔沁沙地、呼伦贝尔沙地和松嫩沙地）进行了表土采样和地球化学分析。结果表明：哈尔滨黄土不含细砂组分（125~250 μm），含有极细砂组分（63~125 μm，4.8%~10.5%），粉砂（4~63 μm）和黏土组分（<4 μm）占绝对优势，分别占73%~82%和12%~18%；粒度模式为三峰态分布（众数分别为36~40、8~10 μm和0.8 μm），与黄土高原典型黄土的粒度分布模式一致，但明显粗于黄土高原中部黄土。哈尔滨黄土经历了初级的化学风化过程，具有较低的成熟度和再循环历史。单靠地球化学方法不能很好地确定哈尔滨黄土的物源，但整合的方法（包括粒度、元素和同位素组成、MDS和PCA统计方法以及自然地理要素等）很好确定了哈尔滨黄土有一个混合源，松嫩沙地松花江水系沉积物为哈尔滨黄土提供了主要的粉尘贡献，浑善达克沙地和科尔沁沙地为哈尔滨黄土提供了部分细颗粒粉尘。     

马氏珠母贝外海深水区养殖的初步研究

采用延绳式、浮筏式、立桩式在外海深水区进行马氏珠母贝［Ｐｉｎｃｔａｄａ ｍ ａｒｔｅｎｓｉｉ （Ｄｕｎｋｅｒ）］人工养殖试验，结果表明：经 １１ 个月的养殖，其成活率分别为延绳式 ５６．３％ ，浮筏式 ３２．８％ ，立桩式２０．８％ ，而同期在港湾浅水区养殖时，其成活率分别为浮筏式 ２８．８％ ，立桩式 １８．５％ 。而且外海深水区养殖马氏珠母贝生长快，个体大，体质强，病害少，附着物少。此外，外海深水区延绳式养殖设施抗风浪能力强，是开发利用外海深水区的一种良好方式     

压裂防砂技术在南堡35—2油田大斜度井的应用

南堡35—2油田明化镇组储层为中高孔、中高渗疏松砂岩稠油油藏，需要压裂防砂来实现增产和防砂。根据端部脱砂压裂的原理，并结合南堡35—2油田A16井明化镇组储层特点，优选出适合该井压裂防砂的清洁压裂液、支撑剂和工具，针对井斜大的特点优化了压裂防砂工艺，采用一趟管柱对明化镇1油组和0油组成功进行了压裂防砂施工。压后油井产液量提高明显，且不出砂，证明压裂防砂达到了增产和防砂的双重作用，是开发疏松砂岩稠油油藏的一项进攻性措施。     

平度旧店金矿区同成矿构造与金的富集关系

旧店金矿区有金矿脉40余条,矿脉受不同方向的构造控制明显,依据不同方向的构造特征厘定出与金矿的富集关系,其中EW,NE向构造为成矿前期构造,NNE向构造为成矿期构造(即同成矿构造),NW向构造为成矿后期构造,而NNE向同成矿构造为金的富集提供了有利的构造条件.     

A comparison of temporal properties of short and long gamma-ray bursts

In this paper, we have performed a temporal analysis of single pulses from short (46) and long (51) gamma-ray bursts (GRBs) to investigate possible differences in their properties. In particular we pay detailed attention to the asymmetry of pulses. We find that the asymmetry ratio of short GRB pulses clusters around 0.81 and that these pulses are on average more symmetric than those from long GRBs, which have an average value of 0.47. In addition we note that the pulses in short GRBs display exponential rises and fast decays (ERFD) in comparison the fast rise exponential decays (FRED) pulses of long GRBs. The asymmetry ratio does not depend on the full width at half maximum (FWHM) and does not vary with energy channel. Moreover, there is a general trend for slower pulses to be more asymmetric. Finally, we deduce that the asymmetry could be used to probe the emission mechanisms of GRBs.