伶仃洋表层沉积物特征及其泥沙运移趋势

根据伶仃洋表层沉积物的粒度分析资料,探讨表层沉积物的特征,并在此基础上应用Gao-Collins粒径趋势分析方法(GSTA模型)分析了伶仃洋表层沉积物的泥沙净输运趋势。结果表明,伶仃洋表层沉积物共有6种类型,其中以黏土质粉砂分布最广泛。受径流、潮流、波浪和陆架水入侵等多种动力作用,伶仃洋表层沉积物颗粒在北面最粗,南面次之,中间最细,东面略粗,西面略细;分选由中部向东、西两岸逐渐变好,但总体分选差;不同级配的泥沙分布和沉积特征存在差异。伶仃洋泥沙运移规律较复杂,泥沙呈现出向西南输运的总趋势;内伶仃洋四周泥沙受各种力作用,呈现出顺时针方向的环流运移,中心区域为最大浑浊带,泥沙以垂直落淤为主。淇澳岛以南至澳门半岛以东海域受粉砂和黏土向西扩散影响,泥沙向西运移。大屿海峡及外伶仃岛附近海域为高盐水入侵通道,泥沙向西北运移。     

湘黔交界娄山关组层序地层学研究

传统上认为湘黔交界处的中寒武统一下向陶统娄山关组为均一性极强的厚层白云岩,可分性极差。但笔者新近研究发现,其顶、底均为古岩溶不整合面,并有大量颗粒（鲕、豆、核形石）白支岩和藻纹层白云岩夹层,还有许多鸟眼构造、叠层石横行、交错层帐蓬构造存在。据其重向组合规律,将娄山关组分为三段。认为娄山关组由７个三级层序组成,层序界面为古岩溶不整合面或暴露带,每个序都由海进体系域和高水位体系域构成。     

StudyofCurieisothermalsurfaceinSichuanBasinandtheseismicareaonitswesternmar┐gin

ＳｔｕｄｙｏｆＣｕｒｉｅｉｓｏｔｈｅｒｍａｌｓｕｒｆａｃｅｉｎＳｉｃｈｕａｎＢａｓｉｎａｎｄｔｈｅｓｅｉｓｍｉｃａｒｅａｏｎｉｔｓｗｅｓｔｅｒｎｍａｒ┐ｇｉｎＸＩＡＮＺＨＡＮＧ（张先），ＸＩ－ＦＥＮＧＨＵ（虎喜凤），ＪＩＮＧ－ＸＩＵＳＨＥＮ（沈京秀...     

南海东北部海陆深地震联测与滨海断裂带两侧地壳结构分析

南海东北部首次成功实施海陆联合深地震探测,填补了海陆过渡带深地震探测的空白. 利用该次海陆联测地震数据,通过数据处理、震相分析、射线追踪、走时模拟等方法,获得了滨海断裂带附近的纵波地壳速度结构,探明了海陆联测剖面中滨海断裂带可能位置. 地壳速度结构为陆壳结构,地壳厚度由陆地向海区逐步变薄;在上地壳下部普遍存在一层速度为5.5～5.9km·s-1、厚度为2.5～4.0km的低速层,并向海区方向减薄,该区未发现明显的高速层. 滨海断裂带为一纵向低速带,位于南澳台东南35km处,对应于重、磁异常带,断裂带断至莫霍面,是华南陆区正常型陆壳与海区减薄型陆壳的分界地壳断裂.     

Associations of decimetric type Ⅲ bursts with coronal mass ejections and Hα flares

We present a statistical study of decimetric type Ⅲ radio bursts,coronal mass ejections(CMEs),and Hα flares observed in the period from July 2000 to March2005.In total,we investigated 395 decimetric type Ⅲ radio burst events,21% of which showed apparent correlation to CMEs that were associated with Hα flares.We noticed that the Hα flares which were strongly associated with CMEs were gradual events,and82% of them took place before CMEs appeared in the field of view of LASCO C2;that most of the CME-associated radio bursts started in the frequency range around750 MHz with a frequency drifting rate of several hundred MHz s-1,of which both positive and negative ones were recognized; and that the correlation of type Ⅲ radio bursts to CMEs without associated flares is fairly vague,less than 9%.     

Sequence Stratigraphy of the Permian--Triassia Boundary Section of Changxing, Zhejiang, Southern China

Three third-order sequences and about one hundred high-frequency cycles or Milankovitchcycles within the Late Permian Changxingian to Early Triassic Griesbachian are identified in theMeishan Section of Changxing, Zhejiang Province, southern China, the candidate stratotype sec-tion of the global Permo-Triassic boundary, based on a detailed study of the biological,ecological and high-resolution allochthonous cyclic events, microfacies and depositional systems.Furthermore, the stacking pattern of the depositional systems across various Changxingian andGriesbachian sedimentary facies of the Lower Yangtze and the sequence stratigraphic frameworkare outlined with the Meishan section as the principal section. In this paper the habitat types offossil biota are applied to semiquantitative palaeobathymetry and the study of relative sea levelchanges.     

应力释放模型的改进及其在研究台湾地区地震预测问题中的应用.

应力释放模型过去主要用于研究大范围历史大地震活动规律．本文对应力释放模型进行了改进，对其能否运用于区域更小、时段更短、震级更低的情况进行了探讨；以台湾地区近百年6级以上地震为例的研究结果表明，应力释放模型仍然适用．在回溯性的地震预测检验中，用改进的应力释放模型计算出台湾地区地震发生的条件概率强度，并用其预测6级以上地震的发震时刻．结果表明，其预测精度优于泊松模型．      

三维复杂介质中转换波走时快速计算

复杂介质中转换波走时计算是多波勘探地震学中重要内容之一.本项研究利用惠更斯原理和费玛原理,获得了三维复杂介质中转换波快速计算的改进型最小走时树方法.其中,在保证精度的条件下,为了提高三维转换波走时计算效率,首先对初至波最小走时树基本算法进行了改进.本方法通过将转换波分为上、下行波分别进行射线追踪以实现三维转换波走时的快速计算.模型计算表明,方法的计算速度快,而且稳定性强,对多波地震勘探具有较大的应用价值.     

Research on the effect estimation of seismic safety evaluation

IntroductionItisdefinitelystipulatedintheLawofthePeople'sRepublicofChinaonProtectingagainstandMitigatingEarthquakeDisastersthattheseismicsafetyevaluationmustbemadeformajorprojects(includinglifelineprojects)and,accordingtotheresultsobtained,theseismicresistancerequirementsshouldbedetermined.Thenecessityofseismicsafetyevaluationhasbeenrecog-nizedgradually,butthetopicontheeffectofsafetyevaluationhasnotbeenreferredmuch.Gener-allyspeaking,althoughmostpeopleapprovethesocialeffectofsafetyevaluatio…     

新矿物—彭志忠石的发现及研究

彭志忠石产于湖南安化白钨矿区,是一种富含镁、锡、铝的复杂氧化物。矿物为浅黄褐色、浅黄色,少量无色,晶体呈六方板状。晶体化学式为:(Mg,Zn,Fe,Al)_4(Sn,Fe)_2(Al,□)_(10)O_(22)(OH)_2,空间群P_3ml,a=5.692(5)A,c=13.78(2)A,V=386.7A~3,Z=1。D=4.22(3)g/cm~3,H≥8,一轴正晶,ω=1.802(2),ε=1.814(2)。