广昌付坊花岗岩地质特征及侵位机制

付坊花岗岩出露在武夷山西坡中段。在１：５万广昌县幅区调工作中,通过对其岩性、化学万分、结构、构造等演化特征的研究,将其划分为洋背、高洲、胡竹、太和、石咀圩５个单元,归并为一个超单元;根据其Ｕ－Ｐb法同位素年龄确定其侵位时代为晚奥陶世,属加里东造山期岩浆活动的产物;侵位机制属早期底辟、晚期轻气球膨胀强力型主动就位。     

石油勘探开发综合技术的应用—以苏北油田沙埝块断为例

从沙埝油田地质条件和地面条件的复杂性出发,在该油田产能建设中针对性地应用了石油勘探开发综合技术。重点介绍了三维地震处理解释一体化技术、储层横向预测技术、油藏工程研究技术的应用及取得良好的效果和显著经济效益的情况。说明多学科相互渗透的综合技术是油田发展的重要途径。     

江苏武进ZK04孔第四纪地层多重划分

叙述了ＺＫ０４孔第四绿地层的岩石地层、生物地层、磁性地层的划分。岩石地层有析世海门组、启动组、昆山组、湖组和全新世如东组;生物地层划分了１０个孢粉组合带、２个有孔虫组合、２个介形虫组合;磁性地层划分了２个极性世,其中布伦赫斯正极性出现了３次反极性事件即拉尚事件、布莱克事件和吉曼事件。对年代地层进行了详细的讨论。     

The property, age and formation environment of the palaeokarst in Qinghai-Xizang Plateau

The karst landforms distributed on the Qinghai-Xizang (Tibet) Plateau can be genetically classed with the Tertiary underground karst, which were gradually exhumed to the surface with the uplift of the plateau during Quaternary period. The relative deposits of the Tertiary palaeokarst processes, such as the residuum and speleothem, were discovered recently in the southern and southeastern fringe areas of the plateau, where has geological-currently been disintegrated by the headward erosion processes of the modern river systems. The major chemical components of the clay portion of the residuum consist mainly of SiO2C, Al2CO3 and Fe2O3. The clay minerals composition of the clay portion belongs to illite-kaolinite pattern for most of the residuum samples, and kaolinite-illite pattern for a few of the samples. It can be judged from the silicic acid index and the clay minerals composition that the formation of the residuum of the Plateau was in its initial phase. However, such a lower chemical weathering index only reflected the weathering degree in the bottom or lower parts of the lateritic weathering crust. The relatively intensive chemical weathering processes of the surface layers of the lateritic weathering crust could be logically speculated. The surface feature textures of quartz grains in the residuum were formed mainly by the chemical erosion, which revealed a long-term humid-tropical environment when the residuum and the palaeokarst formed.     

应用ATA的对数周期馈源方案于FAST的可能性探讨

介绍应用于美国凤凰计划的Allen望远镜阵(ATA)的对数周期馈源(LPA)概况，初步给出此种馈源的基本参数及性能，仿真估算了其驻波比和方向图，并结合正在进行中的我国500m孔径球面射电望远镜(FAST)计划，探讨了应用这种宽带馈源的可能性及其限制。     

Paleoclimatological and paleoenvironmental records since 4 000 a B. P. in sediments of alpine lakes in Taiwan

The 3 310-m-high Chia-min Lake records the climatic history since 4 ka B. P. in Taiwan. The warm/wet period before 2.2 ka B.P. seemed to correspond to the later part of the Holocene Megathermal, and the cold/dry period during 0–2.2 ka B. P. corresponded to the Katathermal. Before the termination of the Megathermal, an especially warm and humid segment (2.2–2.4 ka B. P.) emerged. The paleoclimatic records from Yuen-yang and Chi-tsai Lakes support the notion that the Megathermal in Taiwan terminated during 2—2.3 ka B. P. A warm segment (820–1 320 AD) in the Katathermal could be considered the Medieval Warm Period. The climate turned cold and dry after 1 320 AD and this indicated the onset of the Little Ice Age. These paleoclimatic variations are also in good agreement with those recorded in Great Ghost Lake.     

鲁中北寿光机械林场遗址的环境与盐业生产活动——炭化植物遗存分析

渤海南岸的莱州湾滩地是中国古代重要的产盐区, 分布有众多盐业遗址。其中, 山东寿光机械林场遗址是一处东周和宋元时期的盐业遗址, 分布有盐灶、盐井和灰坑等遗迹单位。炭化遗存分析结果显示, 遗址中农作物种子的数量较少, 杂草的种类及数量较为丰富, 以藜科、菊科、禾本科、茨藻科为主, 并且发现了数量较多的草本植物茎秆, 植物比例显示出偏向自然生长的状态, 可能与放荒发展草荡以供燃料有关。寿光机械林场在东周时期处于滨海盐生草甸植被分布区, 气候较为温和干旱, 至宋元时期湿地植物增加。土壤盐碱化的环境特征并不适合发展农业, 遗址多为煮盐作坊区, 与生活区间可能隔有一定距离, 或与官府对盐业的管控有关。先民在煮盐时就地取材, 利用周边杂草作为燃料, 煮盐集中在秋末、冬季, 遗址可能存在季节性利用的特征。有关盐业遗址的炭化植物遗存的研究相对较少, 寿光机械林场遗址炭化遗存分析结果可以为研究煮盐燃料及莱州湾滩地盐业作坊区周边的环境与植物类型提供一些线索。

     

ATTEM系统中电流关断期间瞬变电磁场响应求解的研究

在瞬变电磁法中,由于发射电流关断时间不为零、接收线圈的谐振频率有限,早期瞬变电磁信号发生畸变,只能舍弃,因此存在着探测盲区. 针对这一问题,研究了瞬变电磁方法中发射电流关断期间总磁场的形成过程,论证了一次场、二次场和总瞬变场的关系,分析了接收线圈的频率特性和关断时间对瞬变电磁场的影响,提出从总磁场中剔除一次磁场影响的方法,从而获得电流关断期间和电流关断后的早期瞬变电磁场. 采用吉林大学自主研制的瞬变电磁测量系统(ATTEM)在长春市伊通河活断层进行勘探,进一步验证了算法的有效性,缩短了瞬变电磁法的勘探盲区,实现了近地表4 m以下的勘探,可以清晰地分辨近地表的低阻异常,提高了浅层探测精度和分辨率.     

浙江东南印支晚期的构造伸展事件：来自诸暨大爽岩体的证据

出露于浙江省东南部的大爽岩体为黑云母二长花岗岩,LA-ICP-MS锆石U-Pb年代学研究表明该岩体形成于227±2Ma,属印支晚期岩浆作用的产物。地球化学分析显示该岩石低Na2O、富K2O,A/CNK=1.26~1.49(大于1.1),为强过铝质、钾玄质系列花岗岩;岩石稀土总量较高,富Sr(Sr=874.6×10-6~1158×10-6),贫Yb(Yb=3.00×10-6~3.92×10-6),富轻稀土而亏损重稀土,具轻微的负铕异常(δEu=0.68~0.70);相对富集Rb、Th等大离子亲石元素,而亏损Nb、Ta等高场强元素;Sr-Nd同位素分析表明岩石具有较高的初始锶比值(I Sr=0.710718~0.711008)和较低εNd(t)值(εNd(t)=-10.9~-11.1),上述地球化学特征指示该岩体岩浆源区为古老的地壳物质。综合分析认为大爽岩体是古老地壳部分减压熔融的产物,受控于印支造山后的伸展应力作用。     

云南弥渡宝兴厂金矿床成矿模式

宝兴厂矿区地质构造复杂,成矿条件有利。区内北东向响水断裂带是主要的控岩和控矿构造。三类金矿床分别在斑岩成矿期、热液成矿期和表生成矿期成生。文中建立相应的成矿模式。