地震模拟图纸数字化存储的实现

地震模拟图纸数字化存储技术方案设计分为3个环节:图纸扫描并保存为图形文件、图纸信息录入、图纸信息校验。对图纸扫描过程中的各个参数进行分析研究,并给出参数的选定方法和参考值。对关键技术(信息校验)进行分析研究,设计3种校验规则:文件命名校验规则、非法输入规则和放大倍数校验规则。此外,研发图纸信息录入软件和图纸信息校验软件,完成河北省地震局259 744张地震模拟图纸(有震图纸)的数字化存储。     

汉江一级阶地抬升以来北亚热带风尘堆积、发育与东亚季风演变的耦合关系——以郧县段汉江上游谷地为例

风成黄土对东亚冬夏季风优势期转换及起迄时间起到良好指示作用,探究风尘黄土堆积、发育特征与东亚季风演变的耦合关系十分必要。本文通过研究汉江一级阶地上覆黄土-古土壤序列的构型、磁化率、烧失量、粒度、元素组成特征,分析汉江一级阶地抬升以来黄土-古土壤序列的成因及成壤特征,探究东亚冬夏季风的演化序列。结果表明：（1）汉江上游地区黄土-古土壤序列的地层构型为表层土（MS）-近代黄土（L₀）-古土壤（S₀）-过渡层（L_t）-马兰黄土（L₁）,磁化率、粒度、烧失量、元素组成等特征指示各地层成壤强度特征为S₀>L₀/L_t>L₁。（2） 成壤强度指示18000 a BP以来,东亚冬夏季风演替特征为末次盛冰期冬季风强烈→全新世早期冬季风减弱→全新世中期夏季风主导→全新世晚期夏季风减弱~,冬季风强盛,其演变滞后于低纬太阳辐射变化2000~3000 a。（3）该风尘堆积物理化性质对6000~5000a BP的气候恶化期有所响应。总而言之,汉江上游一级阶地上覆黄土为风尘堆积物,指示18000a BP以来东亚季风的变迁规律及季风异常事件,能够体现北亚热带对全球气候变化及极端事件的响应。     

Effects of the modified Huanglian Jiedu decoction on the disease resistance in grey mullet (Mugil cephalus) to Lactococcus garvieae

Lactococcosis is prevalent on grey mullet (Mugil cephalus) in Hong Kong aquaculture resulting in serious economic loss. A compound formulation of Traditional Chinese Medicines (TCM) (modified Huanglian Jiedu decoction (HLJDD)) comprising Rhizoma coptidis, Radix scutellaria, Cortex phellodendri, Fructus gardeniae, Fructus forsythiae and Flos lonicerae japonicae (in a ratio of 3:2:2:3:3:5) were applied as feed supplements to deal with the disease. The Nitroblue tetrazolium activity in blood, bactericidal activity and total immunoglobulin in plasma were significantly enhanced after feeding 1% of this TCM for 28 days. The disease resistances to Lactococcus garvieae in 1% and 2% TCM feeding groups were significantly enhanced. In the in vitro study, the modified HLJDD also activated the plasma bactericidal activities (p < 0.01). Based on this study, 1% modified HLJDD feeding for 28 days may be an optimal dose to prevent L. garvieae infection and could be used in aquaculture industries.     

2013年8月河北蔚县小震群遗漏地震检测与发震构造分析

华北地区近年来小震群活动频繁, 在有数字波形记录的中强地震相对缺乏的背景下, 小震群发震构造精细研究可为华北地区地震危险性分析和地震趋势判断提供重要依据. 本文利用匹配滤波技术对2013年8月22—25日河北蔚县小震群遗漏地震事件进行检测, 并通过地震精定位和震源机制求解分析此次震群的发震构造. 计算结果显示, 通过互相关扫描检测到18次被地震台网常规分析遗漏的地震, 约为地震目录给出的13次地震事件的1.38倍. 该震群发震构造有北东向和北西向两组断裂, 震群活动前期以北东向构造活动为主, 后期地震主要发生在北西向构造, 北西向构造在此次震群活动中地震频度和强度均高于北东向构造. 震源机制计算结果显示北西向构造发震机制以正断拉张为主.      

深井盆地南缘断裂特征与活动性研究

深井盆地是山西断陷盆地带北段内部一个规模很小的次级盆地,为中更新世以来发育的三角型山间小型盆地。盆地附近断裂发育,构造复杂,深井盆地南缘断裂为主控边界断裂,控制着盆地的发展演化。本文通过对地形地貌、断裂剖面、地层测年及地震活动等方面的分析和研究,获得了断裂活动时代和活动速率等参数,综合阐述了断裂的空间展布及活动特征。研究表明:深井盆地南缘断裂晚第四纪期间仍在活动,最新活动时代为晚更新世晚期;断裂具有分段性,西段长约6km,多处可见断裂错断晚更新世地层剖面,属正断倾滑性质;东段表现为盆地与黄土斜坡直接接触,由西向东断裂地貌表现逐渐减弱,未见明显的断裂剖面,止于NW向构造,附近发生的4次4 3/4级地震与该段断裂关系密切。     

Advances in studying interactions between aerosols and monsoon in China

Scientific issues relevant to interactions between aerosols and the Asian monsoon climate were discussed and evaluated at the 33rd “Forum of Science and Technology Frontiers” sponsored by the Department of Earth Sciences at the Chinese Academy of Sciences. Major results are summarized in this paper. The East Asian monsoon directly affects aerosol transport and provides a favorable background circulation for the occurrence and development of persistent fog-haze weather. Spatial features of aerosol transport and distribution are also influenced by the East Asian monsoon on seasonal, inter-annual, and decadal scales. High moisture levels in monsoon regions also affect aerosol optical and radiative properties. Observation analyses indicate that cloud physical properties and precipitation are significantly affected by aerosols in China with aerosols likely suppressing local light and moderate rainfall, and intensifying heavy rainfall in southeast coastal regions. However, the detailed mechanisms behind this pattern still need further exploration. The decadal variation in the East Asian monsoon strongly affects aerosol concentrations and their spatial patterns. The weakening monsoon circulation in recent decades has likely helped to increase regional aerosol concentrations. The substantial increase in Chinese air pollutants has likely decreased the temperature difference between land and sea, which favors intensification of the weakening monsoon circulation. Constructive suggestions regarding future studies on aerosols and monsoons were proposed in this forum and key uncertain issues were also discussed.     

Effects of chemical,mineralogical, and temperature variations on the density and bulk sound velocity of the bottom lower mantle

In this study, we have modeled the density(ρ) and bulk sound velocity(VΦ) profiles of the bottom lower mantle using the experimental thermal equation of state(EoS) parameters of lower-mantle minerals, including bridgmanite, ferropericlase,CaSiO3-perovskite, and post-perovskite. We re-evaluated the literature pressure-volume-temperature relationships of these minerals using a self-consistent pressure scale in order to avoid the long-standing pressure scale problem and to provide more reliable constraints on the thermal EoS parameters. With the obtained thermal EoS parameters, we have constructed the ρ and VΦ profiles of the bottom lower mantle in different composition, mineralogy, and temperature models. Our modelling results show that the variations of chemistry, mineralogy, and temperature have different seismic signatures from each other. The Fe and Al enrichment at the bottom lower mantle can cause an increase in ρ but greatly lower VΦ. A change in mineralogy needs to be considered with the lateral variation in temperature. The cold slabs will be shown as denser regions compared to the normal mantle because of the combined effect of a lower temperature and the presence of a denser post-perovskite at a shallower depth,whereas the hot regions will have a 1–2% lower ρ than the normal mantle. VΦ of both cold slabs and hot regions will be lower than the normal mantle when bridgmanite is the dominant phase in the normal mantle, yet they will be greater once bridgmanite transforms into post-perovskite in the normal mantle. Our modeling also shows that the presence of a(Fe, Al)-enriched bridgmanite thermal pile above the core-mantle boundary will exhibit a seismic signature of enhanced ρ and VΦ, but a reduced VS,which is consistent with the observed seismic anomalies in the large-low-shear-velocity-provinces(LLSVPs). The existence of such a(Fe, Al)-enriched bridgmanite thermal pile thus can help to understand the origin of the LLSVPs. These results provide new insights for the chemical and structure of the deepest lower mantle.     

利用伸缩仪观测体应变资料检测地球自由振荡

将湖州地震台数字伸缩仪线应变观测数据转换成体应变数据,采用功率谱密度估计方法,资料未进行去固体潮处理,准确获得2011年3月11日日本大地震激发的0S4- 0S30基频球型自由振荡,对照PREM模型的理论计算周期,发现观测资料周期与之符合较好.     

含水层中弥散系数的尺度效应

为确定研究区含水层的弥散系数,进一步开展咸水体运移的数值模拟,根据研究区的地质背景和水文地质条件,针对含水层中咸水体分布格局设计并开展了示踪试验。利用试验获得的数据初步分析了咸水体垂向和横向运移特征,提出了依赖于单尺度示踪试验结果推求多尺度下弥散系数的内推-外延法,据此计算了试验尺度上的弥散系数。示踪试验结果直观地反映了咸水体对抽水井中氯离子质量浓度的影响,确定了试验尺度上的横向弥散度为7.42 m,垂向弥散度为41.4 m。基于弥散方程的解析解,采用半程拟合的方法进行尺度效应的分析,确立了横向及垂向弥散度与试验尺度关系分别为y=0.007 5·e^{0.129 3x}和y=0.102 9e^{0.049 2x}。根据上述定量关系可进行同类地区相似条件下的弥散系数计算和尺度效应分析,从而为进一步开展咸淡水交互地带水盐运移的模拟和预测提供参数基础。     

塔里木盆地东南坳陷侏罗系展布特征研究

塔东南坳陷位于塔里木盆地的东南部,勘探程度较低。侏罗系为该区主要油气勘探目的层,明确塔东南坳陷侏罗系展布特征是实现该区油气突破的关键问题。通过分析2015年后实施的最新钻探工程以及最新采集处理的地震、电法剖面,结合钻测井、露头资料,研究塔东南侏罗系分布范围及厚度,结果表明侏罗系在塔东南坳陷广泛发育,仅在且末凸起西部局部地区缺失;瓦石峡凹陷侏罗系十分发育,沉积厚度大,分布范围广,并向阿尔金山前有明显加厚趋势,可作为塔东南坳陷油气勘探目标区。