The magmatic–hydrothermal transition—evidence from quartz phenocryst textures and endoskarn abundance in Cu–Zn skarns at the Empire Mine, Idaho, USA

Information about the magmatic to hydrothermal transition is preserved in late-stage features of quartz phenocrysts and endoskarn alteration in some Cu–Zn skarn deposits such as the Empire Mine in Idaho. Important features include: (1) quartz phenocrysts with strong resorption textures such as vermicular zones of igneous groundmass cutting primary quartz cathodoluminescence banding, (2) anomalous amounts of endoskarn (more than 50% of mineralized rock), (3) high F activities as evidenced by fluorite as an accessory mineral in igneous rocks, in alteration assemblages, and in fluid inclusions and by high F in hydroxyl sites in igneous biotite and amphibole, and (4) direct association of Zn, which normally is deposited distally at low temperature, with Cu in proximal locations and in endoskarn. These features are explained by the following model: (1) F lowers the solidus temperature of the magma, thus changing the timing, temperature, and duration of hydrothermal fluid exsolution. (2) Upon magmatic vapor saturation the F-rich hydrothermal fluids form bubbles that adhere to quartz phenocrysts and chemically corrode/tunnel into the quartz forming vermicular resorption textures. (3) F-rich hydrothermal fluids also promote the formation of endoskarn; silicic rocks are attacked by F-rich fluids in the same sense that carbonate wall rocks are dissolved by weakly to moderately acidic hydrothermal fluids. (4) Low fluid exsolution temperature facilitated by high F activity promotes high Zn/Cu ratios in proximal locations due to the solubility of Zn relative to Cu at lower temperatures. This model may be applicable at other localities such as the world-class Cu–Zn skarn Antamina mine, as well as some tin and rapakivi granites.     

An Operational Precipitable Water Vapor Retrieval Algorithm for Fengyun-2F/VISSR Using a Modified Three-Band Physical Split-Window Method

The Visible and Infrared Spin-Scan Radiometer(VISSR) onboard the Fengyun-2(FY-2) satellite can provide valuable thermal infrared observations to help create a precipitable water vapor(PWV) product with high spatial and temporal resolutions. The current FY-2/VISSR PWV product in operation is produced by using a traditional two-band physical split-window(PSW) method, which produces low quality results under dry atmospheric conditions. Based on the sensitivity characteristics of FY-2 F/VISSR water vapor channel and two split-window channels to atmospheric water vapor, this study developed a new, robust operational PWV retrieval algorithm for FY-2 F to improve the operational precision of the current PWV product. The algorithm uses a modified three-band PSW method, which adds a scale for the water vapor channel in the improved three-band PSW method. Integrated PWV products from the radiosonde data in 2016 are used here to validate the precision of the PWV retrieved by the modified three-band and traditional two-band PSW methods. The mean bias, root mean square error(RMSE), and correlation coefficient of the PWV retrieved by the modified three-band PSW method are 0.28 mm, 4.53 mm, and 0.969, respectively. The accuracy is much better than the PWV retrieved by the two-band method, whose mean bias, RMSE, and correlation coefficient are 12.67 mm, 29.35 mm, and 0.23. Especially, in mid-or high-latitude regions, the RMSE of the PWV is improved from 10 to 2 mm by changing the inversion in the two-band method to the modified three-band PSW method. Furthermore, the modified three-band PSW results show a better consistency with the radiosonde PWV at any zonal belt and season than the two-band PSW results. This new algorithm could significantly improve the quality of the current FY-2 F/VISSR PWV product, especially at sites where the actual PWV are lower than 15 mm.     

利用FY-2F快速扫描资料分析对流初生阶段的云顶物理量特征

基于FY-2F静止气象卫星提供的2015年5—9月的高分辨率数据,通过温度阈值法识别出深、浅对流后,分析和比较了深、浅对流在对流初生(convective initiation,CI)至发展阶段中云顶高度、云顶快速降温率(cloud top cooling rate,CTC)以及多通道差值等云顶物理量特征的变化异同。结果表明:深、浅对流在CI阶段的云顶物理量特征具有相似变化特征,即云顶高度均在短时间内快速上升,CTC值均先减小后增大;深、浅对流差异表现为深(浅)对流云顶上升高度能(不能)超越水汽层高度;深对流CTC最低值较浅对流CTC最低值更低。基于CI阶段深、浅对流的CTC最低值的差异,通过个例验证,表明利用深、浅对流CTC最低值的差异,可以在识别出CI的基础,判断出CI是否发展成为深对流,从而能提前做出预警。     

Modbus在生物采样电子监控系统中的应用

针对深海生物幼体采样的需要,提出一种基于Modbus协议的电子监控系统.首先介绍了Modbus通信协议,并重点研究了Modbus主从机的软件设计.设计实现了电子监控系统的软硬件部分.文章设计的监控系统将电子监控引入深海生物幼体采样,并实现了Modbus规约的网络化控制.系统大大提高了采样系统各部件的工作效率和稳定性,低功耗模式的设计也延长了采样系统的工作时间,一定程度上缓解了海底设备电力不足的困境.系统也适用于普通渔场生物拖网的控制.     

辽西金羊盆地南部髫髻山组陆相火山岩及旋回层序划分

辽西金羊盆地（金岭寺－羊山盆地）南部髫髻山组陆相火山岩发育,为一套以中性为主的基性、中基性、中性火山岩组合。火山岩碱度主要为钙碱性。火山岩形成环境为活动大陆边缘区,这与本区所处大地构造位置相吻合。根据当前火山岩的研究现状,尝试性地对该盆地髫髻山组火山岩进行了火山喷发旋回层序的划分,共划分了四级火山喷发旋回层序。其中 A-A′剖面Ⅰ级 1个,Ⅱ级 5个,Ⅲ级 17个,Ⅳ级 21个; B-B′剖面Ⅰ级 1个,Ⅱ级 5个,Ⅲ级 18个,Ⅳ级 24个。     

基于F型mtDNA D-Loop的厚壳贻贝(Mytilus coruscus)群体遗传多样性研究

为研究东海区厚壳贻贝(Mytilus coruscus)遗传多样性,以厚壳贻贝F mtDNA D-loop为标记,对浙江省舟山嵊山岛、宁波渔山岛、温州南麂岛、福建省宁德湾和莆田南日岛五个海区的厚壳贻贝群体进行了遗传分析。结果表明,厚壳贻贝各群体的遗传多样性差异不明显,在5个群体中,宁德群体的遗传多样性相对最丰富;将5个群体作为一个整体时,呈现出较高的单倍型多样性和较低的核苷酸多样性。对厚壳贻贝5个群体间的遗传分化系数(Fst)和基因流(Nm)进行检测,结果显示群体间Fst值都很低,但Nm值都很高(Nm绝对值1),表明5个群体间存在丰富的基因交流。但宁德群体与浙江沿海的3个群体(嵊山、渔山、温州)的Fst值相对较高,且差异显著(P0.5),表明宁德群体与这3个群体间出现遗传分化。本研究旨在为海洋经济贝类资源的保护管理提供理论依据。     

CCSD主孔榴辉岩中磷灰石的矿物化学特征及对榴辉岩中F、Cl、Sr等元素地球化学行为的影响

为探讨榴辉岩中磷灰石的矿物化学特征及榴辉岩中某些相关元素的地球化学行为,对中国大陆科学钻探(CCSD)主孔500~540m深度的榴辉岩样品进行了岩石化学及磷灰石的矿物化学分析。这些榴辉岩具有不同的矿物组成和化学成分,并可据此分为上下两段,上段500~530m为正常榴辉岩,下段530~540m为高Ti榴辉岩和高Ti-Fe榴辉岩,其原岩可能为类似于辉长质和苦橄质的基性—超基性岩石。其中的磷灰石成分没有明显差别,均为氟—磷灰石,其富F贫Cl的特征可能是造成榴辉岩中高盐度流体包裹体和全岩高F低Cl的主要原因。磷灰石普遍含有一定的Sr、S、Fe元素,多数还含有Cu、Pb、Zn等元素。榴辉岩中P2O5含量与其F、Cl、Sr、S元素的相关程度表明,磷灰石是榴辉岩中F元素的最主要储存库,也是Sr元素的重要储存库之一,而对于Cl元素则只是部分控制,与S元素则没有相关性。榴辉岩中F、Sr及Cl元素的地球化学行为主要受控于磷灰石,因此,在榴辉岩从进变质—退变质过程中,这些元素的活动性直接受控于磷灰石的稳定性。     

断裂密集带在油运聚成藏中的作用——以三肇凹陷和尚2井区块扶杨油层为例

为研究三肇凹陷和尚2井区块扶杨油层油气成藏规律,采用断裂密集带与油气分布叠合的方法,分析断裂密集带在油气成藏分布中的作用.结果表明:三肇凹陷扶杨油层发育35条断裂密集带,尚2井区块扶杨油层发育9条断裂密集带;油主要分布在断裂密集带两侧,少量分布在断裂密集带内部.断裂密集带对油运移的控制作用表现在2方面:(1)断裂密集带边界断裂为油输导断裂;(2)断裂密集带不利于油横穿其侧向运移,但可沿其侧向运移.断裂密集带对油聚集的控制作用表现在2方面:(1)断裂密集带两侧的地垒和断阶构造是油聚集的有利部位;(2)断裂密集带内部的背形构造也是油聚集的有利部位.     

The role of vibrationally excited nitrogen in the ionosphere

Theoretical and experimental aspects of the production, transformation, diffusion and loss of N₂ in the upper atmosphere are considered. The N₂-CO₂ near-resonant system in theD andE regions is taken into account. We describe our understanding of the methods necessary to find the vibrational populations of N₂ and CO₂ (asymmetric mode of CO₂). The calculations of the vibrational temperatures in theD, E, andF regions for the mid-latitude ionosphere and an aurora are presented. The connection between the excited species and the 4.26-m radiation intensities is considered. The models for the rate coefficient of the reaction of O⁺ with N₂ and the electron density decrease resulting from N₂ in the F region are discussed.     

CHLOROPHYLL FLUORESCENCE RATIO F685/F735 IN BROWN ALGAE AND ITS VARIATION UNDER EXCITATION BY TWO TYPES OF LIGHT AND DEHYDRATION

Calculation and comparative study of the chlorophyll fluorescence ratio F685/F735 in brown algae (Laminaria japonica, Underia pinnatifida and Padina crassa) excited by blue and green light showed that the fluorescence ratios were higher when the algae were excited by blue light (440 nm), but reduced obviously under green light (540 nm) excitation. The values also reduced under dehydration but could recover during rehydration if the stress was not serious. The variation of the fluorescence ratio under dehydration was mainly because changes in fluorescence emission at 735 nm were always sharper than those at 685 nm. The ratio was sensitive to stress and has potential as a stress indicator in phycological research. Measurement of the fluorescence excitation spectra showed that the only peak at 540 hm changed apparently during dehydration. It meant that the function of the Chl a /Fucoxanthin protein complex for energy transfer was easily inhibited by water stress. However, no variation of the ratio was foun