陕西淳化圣人桥平缓盖层中复杂褶皱的成因——兼论重力滑动构造的分类

陕西圣人桥附近,复杂多样的褶皱出现在平缓的地台盖层之中。对其成因,争议颇多,或认为推覆作用所致,或认为受断裂作用控制。笔者通过详细研究,认为这些复杂褶皱是一种水底重力滑塌构造。据此,还提出了重力滑动构造新的分类,即重力蠕滑;重力滑塌以及重力滑碎等三类。     

南秦岭东段冷水河向斜构造解析

在系统测量褶皱、断层、节理、线理、擦痕等构造形迹位移参数的基础上,通过构造解析方法,获得了该区自古生代以来的四期构造应力场。四期应力场的方向及性质分别为:(1)以264°～290°方向挤压为主,辅以335°～15°方向拉伸的伸展期;(2)以360°～15°方向挤压为主的压缩期;(3)以50°～60°方向挤压为主的压缩期;(4)以340°～10°方向位伸为主,后辅以284°～295°方向位伸的伸展期。研究表明,四期构造应力场的特征与构造演化的表现是基本一致的。     

Lagged response of phytoplanktonic photosynthetic competence to variation of nitrogen concentration in Jiaozhou Bay, China

Fluorescence-based maximal photochemical efficiency, Fv/Fm, is widely used as an indicator to photosynthetic competence in marine systems. It has been considered a useful parameter diagnosing the nutrient stress on phytoplankton photosynthesis, but many studies argue its usefulness. In the present study, we try to find a temporal relationship between Fv/Fm and nitrogen concentration, and provide a possible explanation on the controversy. We continuously measured Fv/Fm and nitrogen concentration once every 10 days from September 2003 to March 2004 at two stations in Jiaozhou Bay, northern China. It was found that Fv/ffm did not significantly correlate to synchronous nitrogen concentration, but the variation （i.e. the change between two adjacent cruises） of nitrogen concentration of the previous cruise and the variation ofFv/Fm of the current cruise were strongly correlated. This result indicates that a time lag exists between the variation of nutrient status and the subsequent Fv/Fm response. Length of the time lag seems just matched the interval of our measurements （10 days）. In the field, direct dependence of Fv/Fm on nitrogen concentration may not be found because of the lagged response of Fv/Fm to nitrogen concentration variations or physiological acclimation. Our results provide a possible way to explain the previously reported conflicting results on the relationship between Fv/Fm and nutrient status. To give a more-accurate estimate about the length of the time lag, an investigation that includes more frequent measurements is needed.     

2003—2010年青岛经济技术开发区土地利用高分辨率遥感变化监测

该文以青岛市经济技术开发区为研究区域,利用2003,2007和2010年3个时相的遥感影像,分析了土地利用的变迁状况。研究表明,在研究时段的7年间,耕地面积减少趋势显著,总面积减少了1 727.00hm2;另一方面工矿仓储用地面积直线上升,总面积增加了1 703.12hm2。总体上来说,主要表现为耕地向工矿仓储用地和城镇住宅用地的转化,两者的转化量分别占耕地减少总面积的71.16%和14.35%;其次是林地和空闲地向工矿仓储用地的转化,前者的转化量占林地减少总面积的68.86%。     

Multidimensional scaling technique for analysis of magnetic storms at Indian observatories

Multidimensional scaling is a powerful technique for analysis of data. The latitudinal dependence of geomagnetic field variation in horizontal component (H) during magnetic storms is analysed in this paper by employing this technique.     

Comparative Studies on Phosphorus Uptake and Growth Kinetics of the Microalga Tetraselmis subcordiformis and the Macroalga Ulva pertusa

Short-term uptake experiments and long-term semicontinuous culture experiments were performed under the condition of phosphorus (P) limitation to estimate and compare the P uptake and growth kinetics of the microalga Tetraselmis subcordiformis and the macroalga Ulva pertusa. Two new parameters, the maximum specific uptake rate (Vm^sp) and the maximal growth efficiency (β), are introduced to achieve uniformity for the comparison of nutrient uptake and growth efficiency between microalgae and macroalgae. T. subcordiformis possesses 3 times lower half saturation uptake constant, 4 times higher maximal growth rate and 20 times higher maximum specific uptake rate than U. pertusa, while U. pertusa possesses 4 times higher maximal growth efficiency than T. subcordiformis.     

Optimizing precipitation station location: a case study of the Jinsha River Basin

Precipitation stations are important components of a hydrological monitoring network. Given their critical role in rainfall forecasting and flood warnings, along with limited observation resources, determining the optimal locations to deploy precipitation stations presents an important problem. In this paper, we use a maximal covering location problem to identify the best precipitation station sites. Considering the terrain conditions and the characteristics of a rainfall network, the original maximal covering location model is modified with the introduction of a set of additional constraints. The minimum density requirement is used to determine a precipitation station’s coverage range, and three weighting schemes are used to evaluate each demand object’s covering priority. As a typical mountainous watershed with high annual precipitation, the Jinsha River Basin is selected as the study area to test the applicability of the proposed method. Results show that the proposed method is effective for precipitation station configuration optimization, and the model solution achieves higher coverage than the real-world deployment. Compared with the commercial solver CPLEX, a genetic algorithm-based heuristic can significantly reduce the computation time when the problem size is large. Several deployment strategies are also discussed for establishing the optimal configuration of precipitation stations.     

绿山设计软件在三维地震勘探中的应用

绿山设计软件是三维地震勘探野外观测系统的设计软件,其依据测区的地质、地球物理参数以及地理条件,可以生成多种符合要求的观测系统。考虑各种参数的相互制约及相互影响因素,根据东欢坨三维地震勘探项目的要求,利用绿山设计软件,求证了各种参数的设计流程及控制方法,布设特殊的观测系统,达到了勘探目的。     

贵州省喀斯特地貌分布面积及分布特征分析

对贵州省喀斯特地貌进行了特征分析,讨论了喀地貌类型及其与人口、经济、植被和河网密度等的关系。     

三维地震勘探在干厚黄土浅煤层地区的应用

干厚黄土覆盖地区表浅层黄土结构疏松、无潜水位，对地震波吸收强烈，难以开展三维地震勘探，特别是在煤层埋深浅的干厚黄土覆盖丘陵地区。在河东煤田某矿区，经多次试验，采取“高叠加次数、小炮检距、单深井激发、组合接收”等采集技术措施，使用绿山初至折射静校正方法及浮动基准面叠加方法的资料处理技术，最终有效地压制了干扰，提高了信噪比，使反射波更加突出，成像效果明显。