房山花岗闪长岩体长石斑晶的数学特征及相带划分

对北京房山花岗闪长岩体中长石斑晶进行了系统测量,测点密度平均4.37个/km~2,测量标志为长石斑晶长轴长度和长石斑晶线含量等。对测得数据进行了分布统计、有序样品最优分割、和趋势变化分析等处理。揭示了长石斑晶在岩体中的分布规律和数学特征,划分了趋势岩相带,从而提出了较为合理的岩相带划分原则。     

金厂峪金矿床地质特征及成因探讨

本文研究了金厂峪金矿太古代斜长角闪岩中构造岩的特征和分布特点;根据片岩带内存在纯片岩地段、片岩带内有岩墙和两种含金脉体地段所呈现的无对称分带性、岩墙和脉体的接触关系,论述了断裂构造性质、控矿作用、热液充填期次、成矿时代;指出产于斜长角闪岩中的金矿床,并非都形成于太古代,在冀东燕山准地槽内应注意燕山期成矿作用。     

与西太平洋暖池上空对流年际变化相关联的大气环流和海温

诊断分析了热带西太平洋暖池上空对流弱和强的情况下,大气环流和海温所表现出来的差异。本文中西太平洋暖池是指（１１０－１６０°Ｅ,１０－２０°Ｎ）地区,向外射出长波辐射（ＯＬＲ）在该地区具有明显的年际变率。对西太平洋暖池对流弱和强之间大气环流和海温的差别进行了合成分析。首先,利用 ＮＣＥＰ／ ＮＣＡＰ再分析资料和卫星观测的 ＯＬＲ资料进行了分析。之后,利用欧洲中期天气预报中心再分析资料和再分析计算而得的ＯＬＲ资料重复进行了合成分析。合成结果表明由这两套资料所分析得到的结果非常相象。与西太平洋暖池上空弱（强）对流显著对应的大气环流表现为北太平洋副热带高压的西伸（东退）,以及副高西北侧更强（弱）的西风。此外,在局地（即暖池）上空,还显著对应着东（西）风异常和下沉（上升）气流异常。对应于西太平洋暖池对流强弱,最为显著的海温差别（对流弱减去对流强）为印度洋、孟加拉湾和南海的正海温异常。也就是说,西太洋暖池上空的对流与局地海温异常只有微弱的联系,而与其西部的海温异常密切相关。     

Further Studies Of Atmospheric Turbulence In Layers Near The Surface: Scaling The Tke Budget Above The Roughness Sublayer

The second of two experimental studies of the TKE budget conducted on sites of different roughness is described, and results are compared. The first took place within a shallow layer above a small field of mostly bare, cultivated soil; the second was carried out above a roughness sublayer of significant depth on an extensive plain of tall dry grass. Budget terms observed in the second study were scaled with a modified u which compensated for effects of an unusually large stress gradient and ensured that the _m functions would be collinear. By showing that the modification becomes negligible in smaller gradients, it is demonstrated that in normal conditions, budgets observed above significant roughness sublayers should be normalized by scaling in terms of the unreduced Reynolds stress at the sublayer's upper surface. This procedure is shown to be consistent with the expectation that TKE budgets in layers near the surface all scale in fundamentally the same way.Other findings include: (1) the fact that most _m functions previously reported are not quite collinear is attributed to a type of overspeeding known to affect three-cup anemometers; (2) revised _m functions, collinear and largely free of the effects of overspeeding, are determined from a well-established characteristic of the linear _m relation for the stable case; (3) data that define collinear _m functions can also be represented with single hyperbolic curves; (4) dissipation is found to be 10 to 15% too small to balance total TKE production in unstable and neutral conditions and to decrease with increasing z/L in thestable regime; and (5) new relations for based on the observed behaviour of the dissipation deficit provide an improved closure for the set of equations that express the budget terms as functions of _m and z/L.     

鲜水河断裂带的构造大地测量

利用短边GPS点阵、短基线标石阵和精密激光测距 ,在与鲜水河断裂带的断层破裂带垂直的剖面上和构造盆地内进行构造大地测量 ,获得了断层软弱带和断层蠕变带上的最佳形变分布。综合利用相关地学成果和理论 ,揭示了构造形变所隐含的动力学信息 ,识别了断层应变带、塑性流变带和主断面在地面的分布范围。用外围GPS远场联测成果探讨了该断裂带的驱动力机制 ,匡正了其“左旋”运动和现今活动速度的含义。最后 ,评估了该断裂的地震活动趋势     

Chironomid-based paleosalinity records in southern British Columbia, Canada: a comparison of transfer functions

Chironomid remains from Big Lake, British Columbia were analysed and paleosalinities were estimated using a pre-existing transfer function and several developed using new regression methods. A two component partial-least-squares model (PLS-2) had the highest coefficient of determination (R² _(Jackknifed) = 0.75) and lowest root-mean-squared error-of-prediction (RMSEP). As compared to the pre-existing model, it was also less sensitive to the influence of rare taxa. Nevertheless, the marginally larger R² _(Jackknifed) and lower RMSEP do not clearly identify a single best model. The models were applied to Big, Mahoney and Kilpoola lakes, revealing the sensitivity of paleosalinity inferences to model selection. A synopsis of chironomid-based paleosalinities in British Columbia and their correspondence with other paleoclimatic data are presented and discussed.     

Chironomids as indicators of climate change: a 100‐lake training set from a subarctic region of northern Sweden (Lapland)

Multivariate numerical analyses (DCA, CCA) were used to study the distribution of chironomids from surface sediments of 100 lakes spanning broad ecoclimatic conditions in northern Swedish Lapland. The study sites range from boreal forest to alpine tundra and are located in a region of relatively low human impact. Of the 19 environmental variables measured, ordination by CCA identified mean July air temperature as one of the most significant variables explaining the distribution and the abundance of chironomids. Lossonignition (LOI), maximum lake depth and mean January air temperature also accounted for significant variation in chironomid assemblages. A quantitative transfer function was created to estimate mean July air temperature from sedimentary chironomid assemblages using weightedaveraging partial least squares regression (WAPLS). The coefficient of determination was relatively high (r² = 0.65) with root mean squared error of prediction (RMSEP, based on jack-knifing) of 1.13 °C and maximum bias of 2.1 °C, indicating that chironomids can provide useful quantitative estimates of past changes in mean July air temperature. The paper focuses mainly on the relationship between chironomid composition and July air temperature, but the relationship to LOI and depth are also discussed.     

结构平稳随机地震反应时域分析:方法

给出了三种常用的随机地震地面运动过程模型,即理想白噪声模型、金井清模型、改进金井清模型的相关函数表达式.引入状态向量,在状态空间中建立地震地面运动激励下的结构振动方程,并求解出结构的复模态特性和复模态反应.利用复模态叠加法推导出线性时不变多自由度体系在这三种随机地震动激励下的平稳协方差反应的解析式,可在时域内直接计算结构随机反应的统计特征.该方法物理概念清晰,结论简便明确,可作为实际工程结构平稳随机地震反应的实用分析方法.     

The Relative Impact of Regional Scale Land Cover Change and Increasing CO2 over China

A series of 17-yr equilibrium simulations using the NCAR CCM3 (T42 resolution) were performed to investigate the regional scale impacts of land cover change and increasing CO2 over China. Simulations with natural and current land cover at CO2 levels of 280,355, 430, and 505 ppmv were conducted. Results show statistically significant changes in major climate fields (e.g. temperature and surface wind speed) on a 15-yr average following land cover change. We also found increases in the maximum temperature and in the diurnal temperature range due to land cover change. Increases in CO2 affect both the maximum and minimum temperature so that changes in the diurnal range are small. Both land cover change and CO2 change also impact the frequency distribution of precipitation with increasing CO2 tending to lead to more intense precipitation and land cover change leading to less intense precipitation-indeed, the impact of land cover change typically had the opposite effect versus the impacts of CO2. Our results provide support for the inclusion of future land cover change scenarios in long-term transitory climate inodelling experiments of the 21st Century. Our results also support the inclusion of land surface models that can represent future land cover changes resulting from an ecological response to natural climate variability or increasing CO2. Overall, we show that land cover change can have a significant impact on the regional scale climate of China, and that regionally, this impact is of a similar magnitude to increases in CO2 of up to about 430 ppmv. This means that that the impact of land cover change must be accounted for in detection and attribution studies over China.     

利用地层空间的相对稳定性、井资料、地震资料模拟高分辨率波阻抗资料

由于地震资料是带限的,而井资料约束反演过程中的地震反演频带的展宽也是有一定限度的,使得反演地震波阻抗也是带限的。如何进一步拓宽反演地震波阻抗的频带宽度,提高地震资料的分辨率是文中研究的内容。利用井约束下的地震反演波阻抗资料、地震资料及井资料,借鉴地质模拟技术,研究如何利用地层的空间相对稳定性特征,通过相关函数的分析,估计反演更高分辨率的地震波阻抗资料。考虑到地质体空间的相关性及分辨率,相关半径取相关函数从最大点到第1个极值点的范围。在目标函数的计算过程中,既考虑当前计算点的权系数信息,又考虑井外推时的权系数信息,这样使计算结果更加稳定可靠。通过综合模拟计算,能够识别较小砂体