中缅油气管道跨断裂地震变形的GNSS观测

中缅油气管道工程是我国重要的能源战略项目,该工程沿线地质背景复杂、破坏性地震多发,尤其是在云南境内跨越的3条大断裂曾发生过7级以上大震,有再次发生破坏性地震的可能性,对管道安全有潜在威胁。中缅油气管道地震观测项目通过在管道与3条断裂交汇处布设3组GNSS观测点,观测地震可能引起的断层位错,进而估计管道可能的变形影响。基于观测数据,分析影响观测的因素及断层位错的观测误差。管道变形承受能力对比结果表明,GNSS跨断裂变形观测系统能够有效观测断裂的位错,进而估计其对管道产生的影响。     

环境干扰事件引起的“形变异常变化”

通过对山东泰安台形变观测受抽水、灌溉影响及烟台台形变观测受载荷影响的分析,认为同一台站的多套形变固体潮仪器"同步异常"的出现应成为判定异常发生的重要准则;对同一应变过程不同形变仪器的响应量级会有所不同,分量式应变仪对异常反映最有效,其次是伸缩仪。对几次"干扰异常"所揭示的问题进行了初步讨论,并在形变异常判定科学思路方面提出了一些建议。     

Reviews on Potash Deposit Metallogenic Conditions

Potash salt is one of key scarce strategic resources. Searching for large scale of potash salt deposit is one big problerm which Chinese academic community faces. Many new discoveries of world potash deposit have been made in recent ten years, which provide abundant practical information and complement the potash metallogenic theory. Through the summary of the potash forming characteristics at home and abroad, the paper studies the potash forming time, tectonic condition, paleogeographic condition, paleoclimate, basin location and salt source. Potash is mainly formed in Permian, Cretaceous, late Jurassic, Cambrian and Devonian. The combination of structure and environment helps to form large scale of evaporation. The climate cycle is related with crust activity. As the other ore deposit, the formation of potash ore also needs dry climate. Potash is the product of final stage in brine evolution, and therefore, it needs persistent drought climate. However, the climate condition is very complicated. Drought climate belt also occurs in humid climate stage, which is controlled by geomorphology. Potash ore can also form in local drought condition. Generally, potash forms in rock salt basin. However, the actual situation is very complicated. Some potash basin is coincided with rock salt basin, some is on one side of rock salt basin; and some are even in the outside of rock salt basin. Salt materials can be from three sources: marine source, terrigenous source and deep source.The paper gives an overview of the research status about the potash deposit forming conditions, which has great guiding significance for searching potash deposit in China. The paper also summarizes the three types of metallogenic models for potash deposit, including epicontinental metallogenic model, abnormal marine evaporation model and rift valley model. The three models are mainly different in material sources, in which the potash in epicontinental metallogenic model is from seawater; the potash in abnormal evaporation model is from nonmarine brine and the potash in rift valley model is mainly from deep material of volcanic activity.     

塔层风廓线与湍流通量关系的理论与实验研究(一)

本文根据大气边界层与湍流力学理论,研究得到了塔层无量纲风梯度与湍流动量通量在中性及不稳定大气层结中均能满足的理论关系——“塔层KEYPS方程”;并将其数值计算结果与实测数据作了对比,验证结果表明:该关系式和实际情况的吻合程度相当好,因而具有一定的实用价值。     

甘肃老虎山闪长岩的地球化学特征及其成因

位于北祁连造山带东端的老虎山闪长岩侵位在晚奥陶统阴沟群砂板岩中,闪长岩的单颗粒锆石Ｕ－Ｐｂ年龄为４２３．５±２．８Ｍａ,是中志留世侵位的。老虎山闪长岩属于钙碱性岩系,富集ＬＲＥＥ和大离子亲石元素（ＬＩＬＥ）,Ｃｅ／Ｙｂ比值大于１３,Ｔｈ／Ｔａ比值大（１３～４２）,在微量元素分布图中呈现明显的Ｎｂ负异常,具岛弧或活动陆缘环境的特征。虽然老虎山闪长岩具有岛弧地球化学特征,但并不能认为它就产于岛弧环境,因为,在奥陶纪末期,早古生代的北祁连洋盆已经发生闭合,华北板块与柴达木板块已发生碰撞。因此,老虎山闪长岩是造山后侵位的,其成因可能与岩石圈拆沉作用有关。     

Modelling the January and July Climate of 9000 Years before Present

ＭｏｄｅｌｌｉｎｇｔｈｅＪａｎｕａｒｙａｎｄＪｕｌｙＣｌｉｍａｔｅｏｆ９０００ＹｅａｒｓｂｅｆｏｒｅＰｒｅｓｅｎｔ￥ＷａｎｇＨｕｉｊｕｎ（王会军）（ＬＡＳＧ，ＩｎｓｔｉｔｕｔｅｏｆＡｔｍｏｓｐｈｅｒｉｃＰｈｙｓｉｃｓ，ＣｈｉｎｅｓｅＡｃａｄｅｍｙｏｆ...     

汛期短历时强降水过程的闪电特征

对2011年3次短历时强降水天气过程的闪电特征分析结果表明:①3次短时强降水都以负闪为主,负闪占总闪电的比例都在92﹪以上;②小时闪电频数峰值超前降雨峰值1h或同相;③5min闪电频数超前雨量峰值5~60min;④负闪电密集区主要发生在40dBZ以上的回波区,偶尔发生的正闪一般在较弱回波处;闪电大部分发生在回波顶高大于5km以上的区域;多分布在速度不均匀场附近;闪电密集区与VIL大值区对应关系不太好;⑤不同云体,闪电特征不尽相同,闪电频数高峰有的发生在强回波阶段,有的并不是回波最强阶段,而是减弱阶段。强回波前沿出现闪电密集区或前方无回波处发生闪电,预示未来强回波移动的方向;有的云体发展、成熟阶段闪电分布密集,负闪电主要集中在强回波中心附近,云体减弱阶段闪电分散,集中在单体的不同部位。     

二维小波变换在消除相干噪声中的应用

相干噪声常使地震记录中的反射同相轴模糊不清,使得处理解释难以进行。而常规的各种ｆ－ｋ滤波技术不能对其有效地消除,且每种技术都有其局限性,容易产生人为假象,使信号发生很大畸变。我们的技术是利用二维小波变换,把二维地震信号变换到有关频率、时间、波数、空间的一个四维函数。根据信号和相干噪声在频率、时间、波数、空间等方面的局部差异来达到滤波的目的。经过对实际炮集数据的处理表明该方法比ｆ－ｋ滤波技术消除噪声的效果要好,信号的畸变程度更低,并且没有任何限制条件。     

Crustal structure beneath the central Tien Shan from ambient noise tomography

Through analysis of seismic ambient noise recorded by the GHENGIS array, we constructed a high‐resolution 3‐D crustal shear‐wave velocity model for the central Tien Shan. The obtained shear‐wave velocity model provides insight into the detailed crustal structure beneath the Tien Shan. The results obtained at shallow depths are well correlated with known subsurface geological features. Low velocities are found mainly beneath sedimentary basins, whereas high velocities are mainly associated with mountain ranges. At greater depths of ~43–45 km, high velocities were observed beneath the Tarim Basin and Kazakh Shield; these high velocities extend forward in opposite directions and tilt down towards the central Tien Shan to a depth of in excess of 50 km, most likely reflecting lateral variations in crustal thickness beneath the Tien Shan and surrounding platforms.