Submarine landslide identified in DLW3102 core of the northern continental slope,South China Sea

In this paper, we take DLW3101 core obtained at the top of the canyon(no landslide area) and DLW3102 core obtained at the bottom of the canyon(landslide area) on the northern continental slope of the South China Sea as research objects. The chronostratigraphic framework of the DLW3101 core and elemental strata of the DLW3101 core and the DLW3102 core since MIS5 are established by analyzing oxygen isotope, calcium carbonate content, and X-Ray Fluorescence(XRF) scanning elements. On the basis of the information obtained by analyzing the sedimentary structure and chemical elements in the landslide deposition, we found that the DLW3102 core shows four layers of submarine landslides, and each landslide layer is characterized by high Si, K, Ti, and Fe contents, thereby indicating terrigenous clastic sources. L1(2.15–2.44 m) occurred in MIS2, which is a slump sedimentary layer with a small sliding distance and scale. L2(15.48–16.00 m) occurred in MIS5 and is a debris flow-deposited layer with a scale and sliding distance that are greater than those of L1. L3(19.00–20.90 m) occurred in MIS5; its upper part(19.00–20.00 m) is a debris flow-deposited layer, and its lower part(20.00–20.90 m) is a sliding deposition layer. The landslide scale of L3 is large. L4(22.93–24.27 m) occurred in MIS5; its upper part(22.93–23.50 m) is a turbid sedimentary layer, and its lower part(23.50–24.27m) is a slump sedimentary layer. The landslide scale of L4 is large.     

Hydroacoustic estimates of fish biomass and spatial distributions in shallow lakes

We conducted acoustical surveys with a horizontal beam transducer to detect fish and with a vertical beam transducer to detect depth and macrophytes in two typical shallow lakes along the middle and lower reaches of the Changjiang(Yangtze) River in November 2013. Both lakes are subject to active fish management with annual stocking and removal of large fish. The purpose of the study was to compare hydroacoustic horizontal beam estimates with fish landings. The preliminary results show that the fish distribution patterns dif fered in the two lakes and were af fected by water depth and macrophyte coverage. The hydroacoustically estimated fish biomass matched the commercial catch very well in Niushan Lake, but it was two times higher in Kuilei Lake. However, acoustic estimates included all fish, whereas the catch included only fish 45 cm(smaller ones were released). We were unable to determine the proper regression between acoustic target strength and fish length for the dominant fish species in the two lakes.     

CORROSION AND ADHERENCE AT SEA OIL-PLATFORM

Measurements of the adhesive corrosion and protective potentials of 3 Bohai Sea oilplatforms under different cathodic protection showed corrosion still occurred on these platforms undertheir designed protective potentials. Preliminary conclusions from indoor experiments on the relation betweenadhesive corrosion and cathodic protection showed adhering organisms caused the corrosion onthese platforms.     

Research progress of TiO2 photocathodic protection to metals in marine environment

Corrosion protection has become an important issue as the amount of infrastructure construction in marine environment increased.Photocathodic protection is a promising method to reduce the corrosion of metals,and titanium dioxide(TiO_2) is the most widely used photoanode.This review summarizes the progress in TiO_2 photo gene rated protection in recent years.Different types of semiconductors,including sulfides,metals,metal oxide s,polymers,and other materials,are used to design and modify TiO_2.The strategy to dramatically improve the efficiency of photoactivity is proposed,and the mechanism is investigated in detail.Characterization methods are also introduced,including morphology testing,light absorption,photoelectrochemistry,and protected metal observation.This review aims to provide a comprehensive overview of Ti02 development and guide photocathodic protection.     

打桩振动对周围环境的影响

在城市建筑物密集区进行振动沉管施工,引起震动对周围环境的影响已成为地基处理施工中一个突出的问题,通过对某项工程水泥粉煤灰碎石柱(CFG)桩施工振动对周边建筑物影响的测试和分析,对地基处理方法的选型及如何有效减轻和控制施工振动对周围环境的影响,均具有一定意义。     

北大巴山早古生代地幔交代作用与煌斑岩浆的起源和演化

产于陕西岚皋境内、赋存于碱质煌斑杂岩中的金云角 闪 辉石岩捕虏体是交 代地幔捕虏体。微量元素和SrNd同位素的对比研究表明,金云角闪辉石岩型交代地幔是寄 主煌斑岩的源区。金云角闪辉石岩捕虏体富含高Na、Ti的角闪石是本区寄主煌斑岩富Ti, 具 低K/Na值的根本原因。煌斑杂岩的同位素地球化学研究表明,早古生代地幔交代作用相对 于煌斑岩的侵位是一个相对近的时间间隔,大约发生于距今600～700 Ma。寄主煌斑岩 的 原生岩浆是金云角闪辉石岩型地幔经较大程度部分熔融而形成,原生岩浆为相似于橄榄金伯 利岩和橄辉玢岩的碱质超基性煌斑岩浆,其经初步分离结晶后形成两个不同的母岩浆,分别 相当于橄榄金伯利岩浆和橄辉玢岩岩浆,两个母岩浆各自具有不同的分离结晶系列,形成不 同的岩石类型。     

试论碳酸盐岩上覆红土的形成模式及演化趋势

据长期对岩溶及红土化作用等的研究成果,本文全面系统地分析了碳酸盐岩上覆红土的形成及演化规律,提出了一个新的碳酸盐岩上覆红土的形成模式,进而深入阐明了碳酸盐岩上覆红土的演化规律及其在现代气候条件下的演化趋势等,在解决岩溶及红土学术界存在的碳酸盐岩上覆红土的形成、碳酸盐岩与上覆红土之间的相互关系及其发展演化规律等一系列重大疑难问题上向前迈进了一步,对相关学科的发展将产生积极的推动作用.     

The comparison analysis of Chinese public perception of earthquakes on different time scales

China has suffered from severe earthquake disasters in recent years. In order to explore the impact of severe earthquakes on public risk perception on different time scales, four surveys were conducted twice each after the severe Wenchuan and Yushu earthquakes. t tests were performed between two consecutive surveys to explore the change of public risk attitudes. The results demonstrated that after the two severe earthquakes, the public seismic risk acceptance has increased over time, and the comparison between pre- and post-Yushu earthquake illustrated that the severe disaster had more impact on vulnerable population such as females, children and low-income people. Moreover, linear regression models were employed to find the determining factors of public acceptance towards earthquake risks. It was discovered that the public perceived earthquake effect had significant negative relationship with seismic risk acceptance, and public trust towards local government had positive relationship with the risk acceptance. This study could help government to gain better understanding of public mental status and take more effective disaster preparedness measures when preventing and responding to a severe earthquake.     

地气测量在内蒙老羊壕金矿区的某些试验成果

以内蒙老羊壕金矿区为试验基地 ,引进抽气法地气测量 ,探讨了地气测量在内蒙干旱荒漠区寻找浅覆盖区隐伏金矿床的有效性。并以试验资料为依据 ,初步探讨了抽气法地气测量中的若干问题 ,指出了抽气法地气测量中存在微尘颗粒干扰。对寻找隐伏金矿床的多元素地气测量 ,采用经 0 .2 2 μm微孔滤膜过滤泡沫塑料吸附为好。已有资料显示可能有超微粒 (接近纳米级 )物质自深部矿体迁移上来     

辉石巨晶中的硫化物及其成因

我国一些地区玄武岩辉石巨晶中的硫化物球泡(0.02-0.05mm)呈点阵式、散布式、定向带状或微裂隙羽状分布。硫化矿物组合是磁黄铁矿-镍黄铁矿-黄铜矿,其中以磁黄铁矿为主(～90％)。根据硫化物的规则排布以及高温矿物组合推测点阵式、散布式硫化物形成于地幔。是由溶解了～1％S的硅酸盐熔体在减压上升过程中析出过饱和的硫所致。