Generation of Deccan Trap magmas

Deccan Trap magmas may have erupted through multiple centers, the most prominent of which may have been a shield volcano-like structure in the Western Ghats area. The lavas are predominantly tholeiitic; alkalic mafic lavas and carbonatites are rare. Radioisotope dating, magnetic chronology, and age constraints from paleontology indicate that although the eruption started some 68 Ma, the bulk of lavas erupted at around 65–66 Ma. Paleomagnetic constraints indicate an uncertainty of ± 500,000 years for peak volcanic activity at 65 m.y. in the type section of the Western Ghats. Maximum magma residence times were calculated in this study based on growth rates of “giant plagioclase” crystals in lavas that marked the end phase of volcanic activity of different magma chambers. These calculations suggest that the > 1.7 km thick Western Ghats section might have erupted within a much shorter time interval of ∼ 55,000 years, implying phenomenal eruption rates that are orders of magnitude larger than any present-day eruption rate from any tectonic environment. Other significant observations/conclusions are as follows: (1) Deccan lavas can be grouped into stratigraphic subdivisions based on their geochemistry; (2) While some formations are relatively uncontaminated others are strongly contaminated by the continental crust; (3) Deccan magmas were produced by 15–30% melting of a Fe-rich lherzolitic source at ∼ 3–2 GPa; (4) Parent magmas of the relatively uncontaminated Ambenali formation had a primitive composition with 16%MgO, 47%SiO₂; (5) Deccan magmas were generated much deeper and by significantly more melting than other continental flood basalt provinces; (6) The erupted Deccan tholeiitic lavas underwent fractionation and magma mixing at ∼ 0.2 GPa. The composition and origin of the crust and crust/mantle boundary beneath the Deccan are discussed with respect to the influence of Deccan magmatic episode.     

长白山天池火山密码破译势在必行

长白山天池火山是中新世以来多次喷发并造成严重灾害的火山。通过十几年的火山地质及火山地震监测研究认为长白山天池火山近期不会马上喷发，但它是一座具有潜在喷发危险性的活动火山，并提出建立长白山火山观测站的重要意义，讨论了天地火山密码的破译需要调动各方面有利因素和有利条件。     

800KaB．P．来西藏“一江两河”中游地区的气候与西南季风变化

西藏“一江两河”中游地区风成地层沉积时代、沉积相和磁化率等研究结果表明，早在８００ＫａＢ．Ｐ．前西南季风就已存在，受全球气候波动和青藏高原隆起的影响，其盛行衰变与东南季风具有较好的一致性，主要表现为本区地层所记录的气候变化信息不如东南季风区详细；而且西南季风因高原屏障作用给本区带来的降水愈来愈少，气候明显地向干冷化发展。     

沂沭泗防汛水情信息系统

沂沭泗防汛水情信息系统是防汛调度决策支持系统中的一个重要组成部分。主要介绍系统的开放性、水情信息处理的自适应性、水情信息图形化、图形漫游、水情信息综合显示、多窗口结合、图形叠加、人机对话、历史资料检索以及屏幕绘图与绘图仪绘图相对应等主要设计特点。     

青藏高原东北部古喀斯特过程与环境

本文介绍了青藏高原东北部地区的古喀斯特现象，并对相关沉积进行了化学成、粘土矿物的Ｘ－射线衍射以及石英砂表面结构等气候代用指标的分析。分析结果一致，指示了温暖湿润的亚热带气候条件。重结晶方解石的裂变径迹测年结果表明，该地区古喀斯特发育于中中新世。     

数字化线性地图要素的综合

本文从制图线理论出发,侧重讨论了数字化线性地图要素(链)的综合方法,并编写了与之相应的计算机自动综合程序,以用于机助制图。     

遥感用于地震预报的途径

本文提出了遥感用于地震预报的思路、途径及步骤,并从理论上进行了阐述。     

Analytical dynamic orbit improvement for the evaluation of geodetic-geodynamic satellite data

Summary Given an analytical solution (solution of the equations of motion using analytical integration techniques) an integration of the variational equations is not necessary but simply a differentiation of the analytical solution. Based on a high-precision analytical solution explicit expressions for the coefficients of the observation equations to improve state variables and force model parameters have been derived.The definition of suitable unknowns for a pure dynamic orbital improvement can be based then on an analysis of the information content of the data at hand by using those expressions.Regarding the Fourier series structure of orbital perturbations as well as the special properties of crossover difference data, the proposed technique is particularly favourable for an evaluation of Remote Sensing Data such as altimeter, SST and gradiometer data from satellites in repeating orbits.After a general discussion of the observation equations for crossover data our present results using GEOSAT altimeter data are discussed as one example for applications. Some short remarks about further applications are given.     

从钠溪气田看阳新统裂缝型气藏分布复杂性

本文以纳溪气田的实际资料，特别是纳６井裂缝系统的典型资料，裂缝系统在纵横向上的分布具明显的方向性和系统中流体分布异常，剖析川南地区二叠系阳新统裂缝型气藏分布的复杂性，为裂缝型气藏的勘探提供借鉴。