Some salient features of the atmosphere observed over the north Bay of Bengal during BOBMEX

This paper describes the near surface characteristics and vertical variations based on the observations made at 17.5degreesN and 89degreesE from ORV Sagar Kanya in the north Bay of Bengal during the Bay of Bengal Monsoon Experiment (BOBMEX) carried out in July-August 1999. BOBMEX captured both the active and weak phases of convection. SST remained above the convection threshold throughout the BOBMEX. While the response of the SST to atmospheric forcing was clearly observed, the response of the atmosphere to SST changes was not clear. SST decreased during periods of large scale precipitation, and increased during a weak phase of convection. It is shown that the latent heat flux at comparable wind speeds was about 25-50% lower over the Bay during BOBMEX compared to that over the Indian Ocean during other seasons and tropical west Pacific. On the other hand, the largest variations in the surface daily net heat flux are observed over the Bay during BOBMEX. SST predicted using observed surface fluxes showed that 1-D heat balance model works sometime but not always, and horizontal advection is important. The high resolution Vaisala radiosondes launched during BOBMEX could clearly bring out the changes in the vertical structure of the atmosphere between active and weak phases of convection. Convective Available Potential Energy of the surface air decreased,by 2-3 kJ kg(-1) following convection, and recovered in a time period of one or two days. The mid tropospheric relative humidity and water vapor content, and wind direction show the major changes between the active and weak phases of convection.

El Nino and the Indian rainfall in June

We have addressed the question of whether the massive deficit of 42% in rainfall over the Indian region in June 2014 can be attributed primarily to the El Nino. We have shown that the variation of convection over the Northern part of the Tropical West Pacific (NWTP: 120-150E, 20-30N) plays a major role in determining the all-India rainfall in June with deficit (excess) in rainfall associated with enhancement (suppression) of convection over NWTP. In June 2014, the outgoing long wave radiation (OLR) anomaly over this region was unfavourable, whereas in June 2015, the OLR anomaly over NWTP was favourable and the all-India rainfall was 16% higher than the long-term average. We find that during El Nino, when the convection over the equatorial central Pacific intensifies, there is a high propensity for intensification of convection over NWTP. Thus, El Nino appears to have an impact on the rainfall over the Indian region via its impact on the convection over the West Pacific, particularly over NWTP. This occurred in June 2014, which suggests that the large deficit in June 2014, could be primarily attributed to the El Nino acting via intensification of convection over NWTP.

Phase synchronization between stratospheric and tropospheric quasi-biennial and semi-annual oscillations

A combination of singular systems analysis and analytic phase techniques are used to investigate the possible occurrence in observations of coherent synchronization between quasi-biennial and semi-annual oscillations (QBOs; SAOs) in the stratosphere and troposphere. Time series of zonal mean zonal winds near the Equator are analysed from the ERA-40 and ERA-interim reanalysis datasets over a ∼ 50-year period. In the stratosphere, the QBO is found to synchronize with the SAO almost all the time, but with a frequency ratio that changes erratically between 4:1, 5:1 and 6:1. A similar variable synchronization is also evident in the tropical troposphere between semi-annual and quasi-biennial cycles (known as TBOs). Mean zonal winds from ERA-40 and ERA-interim, and also time series of indices for the Indian and West Pacific monsoons, are commonly found to exhibit synchronization, with SAO/TBO ratios that vary between 4:1 and 7:1. Coherent synchronization between the QBO and tropical TBO does not appear to persist for long intervals, however. This suggests that both the QBO and tropical TBOs may be separately synchronized to SAOs that are themselves enslaved to the seasonal cycle, or to the annual cycle itself. However, the QBO and TBOs are evidently only weakly coupled between themselves and are frequently found to lose mutual coherence when each changes its frequency ratio to its respective SAO. This suggests a need to revise a commonly cited paradigm that advocates the use of stratospheric QBO indices as a predictor for tropospheric phenomena such as monsoons and hurricanes. © 2012 Royal Meteorological Society.

Cross-Ocean distribution of Rhodobacterales bacteria as primary surface colonizers in temperate coastal marine waters

Bacterial surface colonization is a universal adaptation strategy in aquatic environments. However, neither the identities of early colonizers nor the temporal changes in surface assemblages are well understood. To determine the identities of the most common bacterial primary colonizers and to assess the succession process, if any, of the bacterial assemblages during early stages of surface colonization in coastal water of the West Pacific Ocean, nonnutritive inert materials (glass, Plexiglas, and polyvinyl chloride) were employed as test surfaces and incubated in seawater off the Qingdao coast in the spring of 2005 for 24 and 72 h. Phylogenetic analysis of the 16S rRNA gene sequences amplified from the recovered surface-colonizing microbiota indicated that diverse bacteria colonized the submerged surfaces. Multivariate statistical cluster analyses indicated that the succession of early surface-colonizing bacterial assemblages followed sequential steps on all types of test surfaces. The Rhodobacterales, especially the marine Roseobacter clade members, formed the most common and dominant primary surface-colonizing bacterial group. Our current data, along with previous studies of the Atlantic coast, indicate that the Rhodobacterales bacteria are the dominant and ubiquitous primary surface colonizers in temperate coastal waters of the world and that microbial surface colonization follows a succession sequence. A conceptual model is proposed based on these findings, which may have important implications for understanding the structure, dynamics, and function of marine biofilms and for developing strategies to harness or control surface-associated microbial communities.

Extracellular hydrolytic enzyme screening of culturable heterotrophic bacteria from deep-sea sediments of the Southern Okinawa Trough

The Southern Okinawa Trough is an area of focused sedimentation due to particulate matter export from the shelf of the East China Sea and the island of Taiwan. In order to understand the geomicrobiological characteristics of this unique sedimentary environment, bacterial cultivations were carried out for an 8.61 m CASQ core sediment sample. A total of 98 heterotrophic bacterial isolates were characterized based on 16S rRNA gene phylogenetic analysis. These isolates can be grouped into four bacterial divisions, including 13 genera and more than 20 species. Bacteria of the gamma-Proteobacteria lineage, especially those from the Halomonas ( 27 isolates) and Psychrobacter ( 20 isolates) groups, dominate in the culturable bacteria assemblage. They also have the broadest distribution along the depth of the sediment. More than 72.4% of the isolates showed extracellular hydrolytic enzyme activities, such as amylases, proteases, lipases and Dnases, and nearly 59.2% were cold-adapted exoenzyme-producers. Several Halomonas strains show almost all the tested hydrolases activities. The wide distribution of exoenzyme activities in the isolates may indicate their important ecological role of element biogeochemical cycling in the studied deep-sea sedimentary environment.

ABUNDANCE OF CHEMICAL-ELEMENTS IN CONTINENTAL-SHELF SEDIMENT OF CHINA

For the first time, an element abundance table of China Shelf Sea sediments is published based on 286 samples from the continental shelf of China analyzed for 62 chemical elements. The shelf sediments result from the redistribution of sediments from China over the continental shelf. On the basis of comparison of element abundances among the China shelf samples, hemipelagic Okinawa Trough samples, and pelagic brown clay from the West Pacific, it is clear that each has its own elemental characteristics. Hg anomaly enrichment in Okinawa Trough sediments may be used as an indicator of hydrothermal activity.

大气季节内振荡对东亚夏季风活动的影响研究

利用ERA40逐日再分析资料、NCEP/NCAR2逐日再分析资料、中国740个测站日降水资料、上海台风研究所提供的西太平洋热带气旋资料、Kaplan等重建的月平均SSTA资料、NOAA逐日长波辐射（OLR）等资料，应用离散功率谱分析、带通滤波、EOF分析等统计方法，研究了东亚夏季风(EASM）的移动特征、东亚地区季节内振荡(ISO)的基本特征、季节内振荡对东亚夏季风活动的影响、季节内振荡对东亚夏季风异常活动的影响机理。主要结论如下： （1）综合动力和热力因素定义了可动态描述东亚夏季风移动和强度的指数，并利用该指数研究了东亚夏季风的爆发和移动的季节内变化及其年际和年代际变化特征。研究发现，气候平均东亚夏季风前沿分别在28候、33候、36候、38候、40候、44候出现了明显的跳跃。东亚夏季风活动具有显著的年际变率，主要由于季风前沿在某些区域异常停滞和突然跨越北跳或南撤引起，造成中国东部旱涝灾害频繁发生。东亚夏季风的活动具有明显的年代际变化，在1965年、1980年、1994年发生了突变，造成中国东部降水由“南旱北涝”向“南涝北旱”的转变。 （2）东亚季风区季节内变化具有10~25d和30~60d两个波段的季节内振荡周期，以30-60d为主。存在三个主要低频模态，第一模态主要表征了EASM在长江中下游和华北地区活动期间的低频形势；第二模态印度洋-菲律宾由低频气旋式环流控制，主要表现了ISO在EASM爆发期间的低频形势；第三模态主要出现在EASM在华南和淮河活动期间的低频形势。第一模态和第三模态是代表东亚夏季风活动异常的主要低频形势。 （3）热带和副热带地区ISO总是沿垂直切变风的垂直方向传播。因此，在南海-菲律宾东北风垂直切变和副热带西太平洋北风垂直切变下，大气热源激发菲律宾附近交替出现的低频气旋和低频反气旋不断向西北传播，副热带西太平洋ISO以向西传播为主。中高纬度地区，乌拉尔山附近ISO以向东、向南移动或局地振荡为主；北太平洋中部ISO在某些情况下向南、向西传播。 （4）季风爆发期，伴随着热带东印度洋到菲律宾一系列低频气旋和低频反气旋， 冷空气向南输送，10~25天和30~60天季节内振荡低频气旋同时传入南海加快了南海夏季风的爆发。在气候态下，ISO活动表现的欧亚- 太平洋（EAP）以及太平洋-北美（PNA）低频波列分布特征(本文提出的EAP和PNA低频波列与传统意义上的二维定点相关得到的波列不同)。这种低频分布形式使得欧亚和太平洋中高纬度的槽、脊及太平洋副热带高压稳定、加强，东亚地区的低频波列则成为热带和中高纬度ISO相互作用影响东亚夏季风活动的纽带。不同的阶段表现不同的低频模态，30~60d低频模态的转变加快了EASM推进过程中跳跃性；30-60d低频模态的维持使得EASM前沿相对停滞。 （5）30-60d滤波场，菲律宾海域交替出现的低频气旋和低频反气旋不断向西北传播到南海-西太平洋一带。当南海-西太平洋地区低频气旋活跃时，季风槽加强、东伸，季风槽内热带气旋（TC）频数增加；当南海-西太平洋低频反气旋活跃时，季风槽减弱、西退，TC处于间歇期，生成位置不集中。 （6）在El Nino态下，大气季节内振荡偏弱，北传特征不明显，但ISO由中高纬度北太平洋中部向南和副热带西太平洋向西的传播特征显著，东亚地区ISO活动以第三模态为主，EASM集中停滞在华南和淮河流域，常伴随着持续性区域暴雨的出现，易造成华南和江淮流域洪涝灾害，长江和华北持续干旱。在La Nina态下，大气季节内振荡活跃，且具有明显的向北传播特征，PNA低频波列显著，东亚地区ISO活动以第一模态单峰为主；EASM主要停滞在长江中下游和华北地区，这些地区出现异常持续强降水，华南和淮河流域多干旱；在El Nino态向La Nina态转换期，ISO活动以第一模态双峰为主，长江中下游常常出现二度梅。

西太平洋特定海域沉积物的地磁场相对强度研究

沉积物可以提供连续的地磁场相对强度（RPI）记录，这些记录在全球范围内的对比具有一致性。目前RPI记录越来越多地在布容极性期内作为千年尺度高精度的地层对比手段，但由于构建RPI所需的岩石磁学标准较高，总体来说，RPI数据还相对缺乏，尤其是太平洋地区连续的RPI记录更是相对较少。本文以西太平洋特定海域沉积物为研究对象，进行了古地磁和岩石磁学方面等多个参数的综合测量，通过归一化天然剩磁得到了地磁场相对强度变化曲线，为RPI研究提供了新的记录，为研究区测年提供了新的手段。 西菲律宾海的Ph05孔沉积物的岩石磁学和古地磁研究表明，岩芯中的载磁矿物比较单一，以低矫顽力的磁铁矿为主，χ、ARM及SIRM等参数指示的磁性矿物的含量变化不大。磁性矿物的颗粒以准单畴为主，粒度指示参数χARM/χ具有冰期-间冰期旋回变化。通过交变退磁可得到稳定的特征剩磁，32-38 cm及108-110 cm处发现负倾角，并伴随着RPI的低值。谱分析检验后选择ARM作为归一化参数，通过ARM归一化天然剩磁获得了200 ka以来的地磁场相对强度记录。重建的RPI记录与综合曲线Sint-200有良好对比，可以反映全球性的信号。基于RPI建立的年代模型与氧碳同位素年代模型相似，可以作为独立的定年手段。 对东菲律宾海帕里西维拉海盆西侧F090102孔柱样沉积物进行了系统的古地磁和岩石磁学分析，结果表明样品适合进行相对强度研究。根据功率谱分析结果，选择非磁滞剩磁作为归一化的参数，得到约2 Ma以来的地球磁场相对强度变化曲线。该曲线与SINT-2000曲线可详细对比，比如呈比较典型的锯齿状特征，布容期内的记录与800 ka以来的SINT-800曲线相符。布容/松山极性转换期呈单强度降低的特征，在极性转换期和极性漂移期，相对强度曲线表现为显著低值。 对东海内陆架泥质区沉积物EC2005孔的磁学研究表明，岩芯在110 cm即受到还原成岩作用的影响；110-600 cm经历了铁氧化物还原阶段，样品中磁性矿物以PSD磁铁矿为主，随深度增加，其含量快速减少，其间随着硬磁矿物含量的波动，磁学参数也呈现出峰谷变化；600 cm向下岩芯经历硫酸盐还原阶段，各磁学参数都维持在很低的水平，顺磁性颗粒增加，并出现黄铁矿。早期成岩作用及重磁化作用使得古地磁信号被削弱和改造。

东、西太平洋深海沉积物细菌多样性研究

深海生物圈有着不同于陆地和浅海的典型特点，例如高压、低温、永久黑暗及寡营养，并且深海微生物具有特殊的代谢途径及庞大的生物量，这使得深海成为一个巨大的有待开发利用的生物资源宝库。 本文研究的样品分别取自东太平洋E272站位(12°36’39"N, 104°19’28"W)和西太平洋Ph05-5站位(16°04’93"N, 124º34’48"E)。E272站位距离东太平洋13°N海隆45km，水深3 191m；而Ph05-5站位地处西菲律宾海盆，在黑潮源区附近，位于西太平洋暖池区边缘，水深3 382m，并且Ph05-5岩芯一共包含了五个明显的火山灰层。 本文采用了末端限制性片段长度多态性分析（T-RFLP）和16S rRNA 基因文库分析的方法在小尺度上对东太平洋E272站位的沉积物样品进行细菌群落结构的研究。研究结果表明沉积物细菌群落结构在小尺度上存在明显的垂直变化。系统进化分析表明，该沉积物样品的细菌多样性较高，共包含9个主要的门类，包括变形菌门、绿弯菌门（绿色非硫细菌）、浮霉菌门、酸杆菌门、放线菌门（高G+C革兰氏阳性菌）、拟杆菌门、硝化螺旋菌门、以及两个待定的门类OP8和TM6。其中变形菌门细菌是一类在海洋中非常常见的细菌，广泛分布于各个海洋环境，在我们的文库当中发现了变形菌门的三个纲，包括α-、-、-变形菌纲。本项研究充分表明该沉积物环境中具有较高的细菌多样性，在小尺度上细菌群落垂直分布明显，其结果也可从侧面反映深海沉积物近表层处的环境条件在小尺度上的垂直变化显著。 对西太平洋暖池区沉积物样品的细菌群落的研究也采用16S rRNA 基因文库分析的方法。系统进化分析表明该沉积物样品细菌的多样性相对较低，一共包含了六个不同的门类，包括变形菌门、浮霉菌门、放线菌门、厚壁菌门（低G+C革兰氏阳性菌）、绿弯菌门、酸杆菌门。在这个沉积物样品中也发现了变形菌门的三个纲包括α-、-和-变形菌纲。聚类分析和系统进化分析都表明表层的细菌群落同其它8层的细菌群落存在明显的差异，并且其它8层包括5个火山灰层和3个远洋粘土层的细菌群落结构差异不大，推测火山灰成分不仅对火山灰层的细菌群落产生影响，而且可能通过扩散对整个沉积物的微生物群落结构都产生影响。表层可能由于沉积时间较晚所以受影响相对较小或表层本身不同于较深层次的理化条件而使表层群落存在较大差异。 对东、西太平洋不同环境下的两个深海沉积物样品的细菌多样性进行比较，结合其它研究发现变形菌门细菌在不同深海环境中都普遍存在，是深海不同环境的广适类群。另外，两个环境中的细菌多样性存在很大差异，东太平洋沉积环境中的细菌多样性要远高于西太平洋沉积环境中的细菌多样性，推测其最可能的原因是西太平洋沉积物火山灰成分对细菌群落的影响，致使其细菌群落与东太平洋远洋粘土沉积物细菌群落产生很大差异；另外，不同洋区的环境差异也应该是造成细菌群落差异的一个重要方面。

长白山火山成因—物理机制和化学演化

This thesis is one of the contributions to NSFC project, “The Changbaishan Volcanism and its Links to the Northeast Asia Tectonic System”. The thesis presents our most recent works on Changbaishan Volcanism, on two aspects as (1) the chemical evolution of the Cenozoic volcanism and the physical links of magma genesis, (2) the Holocene activity of the Tianchi Volcano and risks of potential eruption. 1. Chemical evolution and physical links to the Changbaishan Volcanism Physical links to the Chanbaishan Volcanism, just like origins of most of the volcanisms in eastern China, has long been an enigma. A large scale of volcanic activity has dominated many places of eastern China in Meso-Cenozoic. Activity of these volcanisms in eastern China covers several quite different blocks, covers variety of tectonics, and covers a period of time over 200 million years. Such a large-scale and long-lived volcanism in a continental area challenges our knowledge on dynamics of the Earth’s interior. Some works on “Diwa” hypothesis and “lithospheric thinning” hypothesis present possible links between volcanisms and dynamic evolutions of the earth’s interior, but still cannot interpret where are the sources of the heat and fluid, which are essential to the volcanisms. Based on the study of this thesis, we suggest that dynamics of the deep subduction of western Pacific Plate is the critical factor to the Changbaishan Volcanism and volcanisms in NE China, and maybe even essential to most of the Meso-Cenozoic volcanisms in eastern China. In NE China, stagnant slabs flatted in the mantle transition zone (MTZ, ca. 660 km deep) transport and release significant hydrous fluid to the upper mantle. Metamorphism of the deep-subducted slabs and hence a series of mineral phases play an important role in the water transport, exchange, restore, and release. Dehydrated fluid of the wet slab ascending from the MTZ fertile the upper mantle, and also provide upward heat flow which is essential to the magma genesis. Then magma and volcanism occur with the deep subduction from Mesozoic to mordern time in eastern China. To discribe the exact chemical characteristics of the deep subduction releated volcanics is very difficult, because few researches has contributed to the chemical behaviors of fluid and trace elments in the very deep interior of the Earth, such 660 km deep, 410km or 350km where the fluid may ascend and react. However we can still find some chemical characteristics of oceanic subduction. Basalts of the Changbaishan Volcanism have siginficant characteristics of potassium rich, and even can be called a potassic igneous province. If there are only two possible ways, recycled continentical crust or oceanic crust, to fertile the mantle potossium element as we know now, it’s easy to attribute this to the deep-subducted of the west Pacific Plate. To the eastern China, fluid inclusions in mantle xenoliths from the Cenozic basalts also reveal potassium-rich characteristics. This reveals that the same potassium feritle agents may occur in the mantle sources of eastern China. 2. Holocene activiy of the Tianchi Volcano As one of the large volcanic center and complex volcanic cone, the Tianchi Volcano is a dangerous active volcano, with several Holocene eruptions. Among these eruptions, the Millennium Eruption is regardede as one of the biggist eruptions in the world in the last 2000 years. To estimate the potential danger of volcanic eruption, we discuss two essential factors, as (i) volcanic history of Holocene eruptions, including volcanic geolgy, chronnology and chemistry, (ii) state, evolution and relationship of the magma chambers in mantle and crust beneath the Tianchi Volcano.

南海沉积物中的放射虫及其古环境意义

In this paper a systematic study of radiolarian from surface sediments of all the South China Sea (SCS) has initially been done for its deposit ecology, biogeography and paleoenvironment significance. The paleoenvironment information obtained by radiolarian analysis and other sedimentary method for core samples is also made use as the synthesis proxy for revealing the paleoenvironment changes in the SCS and the relations of it with the past globe change during last 200ka. Some results come out of this study as: 1) Radiolarian skeleton chemistry composition and skeleton morphological features were analyzed, chiefly dividing them as 15 types of basic morphological features: 2) Analysis of biogeographical feature demonstrates that the fauna in SCS obviously belonging to a transitional type of west Pacific - Indian Ocean and has a particularity of itself: 3) Tendency of radiolarian population distribution is lower in shallow continental shelf area, increasing gradually toward the abyssal region; 4) Nine character boundaries of radiolarian depth distribution in the sediments from whole the South China Sea may be recognized; 5)Two radiolarian transfer functions for paleotemperature and paleo-primary productivity in the South China Sea have also been established respectively. The equation of transfer function for winter paleotemperature has only an average estimated error of 0.18678 ℃ and the equation for paleo-primary productivity has the calculation accuracy of 85.31%; 6) Changes of radiolarian individuals, numbers of species and H(S) values in core NS93-5 show the completely different oceanic geographical circumstance and ecology structure in the Last Maximum Glacial with present; 7) The abundance variation of some raiolarian warm species and cold species indicate the changes of water masse features along with the paleoenvironment evolution, showing that this sea area clearly is controlled in 6 issues of oxygen isotopes by the cold water masses; 8) By comparative analysis of δ ~(18)O curves with GISP2;s ice core can core 17940 of the northern SCS, the occurring characters of D/O's events 1-21 and Heinrich's events H1-H6 have been revealed in this sea area by core NS93-5, which prove the existence of paleoclimatic tele-connections between the southern SCS and Arctic region since about 200ka BP.

大兴安岭南段中生代火山-侵入杂岩带的双层叠置构造体制兼论滇中武定、易门碳酸质火山岩年代、来源及矿库与找矿研究

These are two parts included in this report. In the first part, the zonation of the complexes in its series, lithofacies, the depth of magma source and chambers is discussed in detailed for the first time based on the new data of petrol-chemistry, isotopes, tectono-magma activity of Mesozoic volcano-plutonic complexes in the southern Great Hinggan Mts. Then, the genetic model of the zonality, double overlapped layer system, is proposed. The main conclusions are presented as follows: The Mesozoic volcanic-plutonic complexes in the southern Great Hinggan were formed by four stages of magma activity on the base of the subduction system formed in late Paleozoic. The Mesozoic magmatic activity began in Meso-Jurassic Epoch, flourished in late Jurassic Epoch, and declined in early Cretaceous Epoch. The complexes consist dominantly of acidic rocks with substantial intermediate rocks and a few mefic ones include the series of calc alkaline, high potassium calc alkaline, shoshonite, and a few alkaline. Most of those rocks are characterized by high potassium. The volcano-plutonic complexes is characterized by zonality, and can be divided mainly into there zones. The west zone, located in northwestern side of gneiss zone in Great Xinggan mountains, are dominated of high potassium basalts and basaltic andesite. The middle zone lies on the southeast side of the Proterozoic gneiss zone, and its southeast margin is along Huangganliang, Wushijiazi, and Baitazi. It composed of dominatly calc-alkaline, high potassium calc-alkaline rocks, deep granite and extrusive rhyolite. The east zone, occurring along Kesheketong Qi-Balinyou Qi-Balinzuo Qi, is dominated of shoshonite. In generally, southeastward from the Proterozoic gneiss zone, the Mesozoic plutons show the zones-mica granitites zone, hornblende-mica granitite zone, mica-hornblende granitite zone; the volcanic rocks also display the zones of calc alkaline-high potassium calc alkaline and shoshonites. In the same space, the late Paleozoic plutons also display the same zonality, which zones are combined of binary granite, granodiorite, quartz diorite and diorite southeast wards from the gneiss. Meso-Jurassic Epoch granite plutons almost distribute in the middle zone on the whole. Whereas late Jurassic Epoch volcanic rocks distribute in the west and east zone. This distribution of the volcano-plutonic complexes reveals that the middle zone was uplifted more intensively then the other zones in Meso-Jurassic and late Jurassic Epoches. Whole rock Rb-Sr isochron ages of the high potassium calc-alkaline volcanic rocks in the west zone, the calc-alkaline and high potassium calc-alkaline granite the middle zone, shoshonite in the east zone are 136Ma, 175Ma and 154Ma, respectively. The alkaline rocks close to the shoshonite zone is 143Ma and 126Ma. The isochron ages are comparable well with the K-Ar ages of the rocks obtained previously by other researchers. The compositions of Sr ans Nd isotopes suggest that the source of Mesozoic volcanic-plutonic complexes in Great Hinggan Mts. is mostly Paleo-Asia oceanic volcanic-sedimentary rocks, which probably was mixed by antiquated gneiss. The tectonic setting for Mesozoic magmatism was subductive continental margin. But this it was not directly formed by present west Pacific subduction. It actully was the re-working of the Paleozoic subduction system( which was formed during the Paleo-Asia ocean shortening) controlled by west Pacific subduction. For this reason, Although Great Hinggan Mts. is far away from west Pacific subduction zone, its volcanic arc still occurred echoing to the volcanic activities of east China, it, but the variation trend of potassium content in volcano-plutonic complexes of Great Hinggan is just reverse to ones of west Pacific. The primitive magmas occurred in the southern Great Hinggan Mts. Include high-potassium calc-alkaline basalt, high potassium calc-alkaline rhyolite, high potassium rhyolite, non-Eu negative anomaly trachy-rhyolite et al. Therefore, all of primitive magmas are either mafic or acid, and most of intermediate rocks occurring in the area are the products of Mesozoic acid magma contaminated by the Paleozoic volcanic- sedimentary rocks. The depth of those primitive magma sources and chambers gradually increase from northwest to southeast. This suggests that Paleozoic subduction still controlled the Mesozoic magmatism. In summary, the lithosphere tectonic system of the southern Great Hinggan Mts. controlling Mesozoic magmatism is a double overlapped layer system developing from Paleozoic subduction system. For this reason, the depth of crust of the southern Great Hinggan Mts. is thicker than that of its two sides, and consequently it causes regional negative gravity abnormity. The second part of this report shows the prolongation of the research work carried on in my doctor's period. Author presents new data about Rb-Sr and Sm-Nd isotopic compositions and ages, geochamical features, genesis mineralogy and ore deposit geology of the volcanic rocks in Kunyang rift. On the base of the substantial work, author presents a prospect of copper bearing magnetite ore deposit. The most important conclusions are as follows: 1. It is proved that all of these carbonatites controlled by a ringing structure system in Wuding-Lufeng basin in the central Yunnan were formed in the Mesoproterozoic period. Two stages could be identified as follows: in the first stage, carbonatitic volcanic rocks, such as lavas(Sm-Nd, 1685Ma), basaltic porphyrite dykes(Sm-Nd, 1645Ma), pyroclastic rocks and volcaniclastic sedimentary rocks, formed in the outer ring; in the second stage, carbonatitic breccias and dykes(Rb-Sr, 1048 Ma) did in the middle ring. The metamorphic age of the carbonatitic lavas (Rb-Sr, 893 Ma) in the outer ring was determined. The magma of carbonatitic volcanic rocks derived mainly form enriched mantle whose basement is depleted mantle that had been metasomated by mantle fluid and contaminated by Archaean lower crust. Carbonatitic spheres were discovered in ore bearing layers in Lishi copper mining in Yimen recently, which formed in calcite carbonatitic magma extrusion. This discovery indicates that the formation of copper ore deposit genesis relates to carbonatitic volcanic activity. The iron and copper ore deposits occurring in carbonatitic volcanic- sedimentary rocks in Kunyang rift results from carbonatitic magmatism. Author calls this kind of ore deposits as subaqueous carbonatitic iron-copper deposit. The magnetic anomaly area in the north of Lishi copper mining in Yimen was a depression more lower than its circumference. Iron and copper ores occurrig on the margin of the magnetic anomaly are volcanic hydrothermal deposit. The magnetic body causing the magnetic anomaly must be magnetite ore. Because the anomaly area is wide, it can be sure that there is a large insidious ore deposit embedding there.

中国东海陆架盆地构造-热演化研究

East China Sea Shelf Basin (ECSSB), as a basin with prospect of oil & gas resource and due to its special geological location on the west margin of the west Pacific, attracts a lot of attention from many geologists in the world.Based on systematic temperature measurements, bottom hole temperature (BHT) and the oil temperature data, the geothermal gradients in the ECS SB are calculated and vary from 25 to 43°C/km, with a mean of 32.7°C/km. The geothermal gradient in Fuzhou Sag has the higher value(40.6°C/km) in Taibei Depression than that in others. The lower value (27.2 °C/km) occurs in in Xihu Depression. The middle values occurs in Jiaojiang and Lishui sags in Taibei Depression with a mean value of 34.8 °C/km. Incorporated with the measured thermal conductivity, heat flow values show that the ECSSB is characterized by present-day heat flow around 70.6mW/m2, varying between 55 and 88 mW/m2. No significant difference in heat flow is observed between the Xihu and the Taibei Depressions. These heat flow data suggest that the ECSSB is geothermally not a modem back-arc basin.Applying the paleogeothermal gradient based method, thermal history is reconstructed using vitrinite reflectance (VR) and apatite fission track (AFT) data. The results suggest that the thermal history was different in the Taibei and the Xihu depressions. Paleo-heat flow values when the pre-Tertiary formations experienced their maximum temperature at the end of the Paleocene reached a mean of 81 mW/m2 in the Taibei Depression, much higher than the present-day value. The lower Tertiary sediments in the Xihu Depression experienced maximum temperatures at the end of Oligocene and reached a mean paleo-heat flow value of 83.4 mW/m2. The time, when the paleo-heat flow reached the maximum value, suggests that the ECSSB rifted eastward.Tectonic subsidence analysis shows that the timing of the major rifting episode was different across the ECSSB. The rifting occurred from the Late Cretaceous to the early Eocene in the Taibei Depression, followed by thermal subsidence from the late Eocene to the end of Miocene. In contrast, in the Xihu Depression the initial subsidence lasted until the early Miocene and thermal subsidence to the end of Miocene. From Pliocene to the present, an accelerated subsidence took place all along the West Pacific margin of the east Asia.The thermal lithosphere thickness is determined by temperature profile in the lithosphere, the mantle adiabat or the dry basalt solidus. It indicates that the thermal lithosphere reached the thinnest thickness at the end of Eocene in the Taibei Depression and the end of Oligocene in the Xihu Depression, respectively, corresponding with a value of 57-66km and 56-64km. In Taibei Depression, the lithosphere thickness decreased 16-22km from the end of Mesozoic to Paleocene. After Paleocene, the thickness increased 13-16km and reached 71-79 km at present-day. In Xihu Depression, From the end of Oligocene to present-day, the thickness increased 10-13km and reached 69-76km at present-day. The evolution of the lithosphere thickness is associated closely with the lithosphere stretching.Combining the reconstructed thermal history and the burial history, the maturation of the Jurassic oil-source rock shows that the main hydrocarbon generation phase was in the mid-Jurassic and a secondary hydrocarbon generation occurred at the end of Paleocene. The secondary generation was controlled mainly by the tectono-thermal background during the Paleocene.

Evolution in the deep sea: a combined analysis of the earliest diverging living chitons (Mollusca : Polyplacophora : Lepidopleurida)

Lepidopleurida is the earliest diverged group of living polyplacophoran molluscs. They are found predominantly in the deep sea, including sunken wood, cold seeps, other abyssal habitats, and a few species are found in shallow water. The group is morphologically identified by anatomical features of their gills, sensory aesthetes, and gametes. Their shell features closely resemble the oldest fossils that can be identified as modern polyplacophorans. We present the first molecular phylogenetic study of this group, and also the first combined phylogenetic analysis for any chiton, including three gene regions and 69 morphological characters. The results show that Lepidopleurida is unambiguously monophyletic, and the nine genera fall into five distinct clades, which partly support the current view of polyplacophoran taxonomy. The genus Hanleyella Sirenko, 1973 is included in the family Protochitonidae, and Ferreiraellidae constitutes another distinct clade. The large cosmopolitan genus Leptochiton Gray, 1847 is not monophyletic; Leptochiton and Leptochitonidae sensu stricto are restricted to North Atlantic and Mediterranean taxa. Leptochitonidae s. str. is sister to Protochitonidae. The results also suggest two separate clades independently inhabiting sunken wood substrates in the south-west Pacific. Antarctic and other chemosynthetic-dwelling species may be derived from wood-living species. Substantial taxonomic revision remains to be done to resolve lepidopleuran classification, but the phylogeny presented here is a dramatic step forward in clarifying the relationships within this interesting group.

Larval Transport Modeling of Deep-Sea Invertebrates Can Aid the Search for Undiscovered Populations

Background: Many deep-sea benthic animals occur in patchy distributions separated by thousands of kilometres, yet because deep-sea habitats are remote, little is known about their larval dispersal. Our novel method simulates dispersal by combining data from the Argo array of autonomous oceanographic probes, deep-sea ecological surveys, and comparative invertebrate physiology. The predicted particle tracks allow quantitative, testable predictions about the dispersal of benthic invertebrate larvae in the south-west Pacific. Principal Findings: In a test case presented here, using non-feeding, non-swimming (lecithotrophic trochophore) larvae of polyplacophoran molluscs (chitons), we show that the likely dispersal pathways in a single generation are significantly shorter than the distances between the three known population centres in our study region. The large-scale density of chiton populations throughout our study region is potentially much greater than present survey data suggest, with intermediate ‘stepping stone’ populations yet to be discovered. Conclusions/Significance: We present a new method that is broadly applicable to studies of the dispersal of deep-sea organisms. This test case demonstrates the power and potential applications of our new method, in generating quantitative, testable hypotheses at multiple levels to solve the mismatch between observed and expected distributions: probabilistic predictions of locations of intermediate populations, potential alternative dispersal mechanisms, and expected population genetic structure. The global Argo data have never previously been used to address benthic biology, and our method can be applied to any non-swimming larvae of the deep-sea, giving information upon dispersal corridors and population densities in habitats that remain intrinsically difficult to assess.