1994年AGU香港会议与旧金山会议

本文综述了１９９４年ＡＧＵ香港会议与旧金山会议的概况，介绍了这两次会议中地震预报研究专题的情况，论及了这两次会议的作用与影响。     

分块变换中的边界问题和P4T方法

在分块变换或纠正中,其边界的拓扑性保持是非常重要的。本文从二维变换的角度出发,对一般的分块变换在分析其边界影象错落的普遍性基础上,给出了解决此类问题严密且实用的方法。     

长春地震台用最大振幅和持续时间联合确定的矩震级公式

根据《中国地震台网观测报告》,选取1983—1986年期间的109次地震(5.5≤Ms≤8.5;10°≤Δ≤105°)资料。在宽频带中周期SK地震图上,量取两个水平向尾波振幅减少到S波最大值三分之一处的持续时间,再取它与震中距和最大地动位移的乘积。取对数作为地震矩Mo然后与Ms进行线性拟合,并应用最小二乘法分别计算出我国和NEIS的矩震级公式。从统计结果看,我国和NEIS的矩震级公式的标准偏差分别的0.2400和0.3046。其相关系数均达0.83以上。利用最大振幅和持续时间联合确定的矩震级公式实用性强,能解决巨大震级的饱和问题;同时,对面波限幅的地震解决了计算震级的困难。     

利用树木车轮资料重建西藏中部过去气候的初步尝试

为较可靠地利用年轮气候学方法重建过去气候，本文依据西藏中部，四个经过合适取样和精确定年的树木年轮年表，首先确立了它们各自生长状况对气候要素的响应函数，进一步明确年轮宽度与气候变化的关系。接着，选择可被重建的气候因子，并建立包括前期生长在内的、经过正交变换的转换函数，达到重建过去气温和降水的目的。此外，还划出不同的校准期和验证期，采用统计方法和其它类型代用资料进行检验。     

DISTRIBUTION OF DISSOLVED AND PARTICULATE TRACE METALS IN ANOXIC SEAWATER, SAANICH INLET, B . C. CANADA

This paper discusses the spatial and seasonal distribution character of dissolved and paniculate trace metals in the anoxic seawater of Saanich Inlet, B.C., Canada. The study showed that concentration of dissolved and paniculate trace metals in anoxic seawater is closely related to (1) the concentration of H2S and the depth of the O2-H2S interface, (2) the exchange of seawater in Saanich Inlet with outside seawater, (3) biotic action, and (4) the flushing event. The study was based in part on the ratio between trace metals and nutrients. There was a steep change in the concentration of dissolved trace metals at the O2-H2S interface. The concentration of dissolved trace metals in the H2S-controlled zone was dependent on the H2S there. The suspended matter in Saanich Inlet comes from the Hero Strait seawater, phytoplankton production and resuspension of flushed-up sediments. The concentration of particulate trace metals was rather low in Saanich Inlet and tended to increase with depth. The total concentra     

吉林桦甸太古代杂岩的矿物化学和变质作用温压条件

本文重点研究了桦甸杂岩的主要造岩矿物黑云母、角闪石、辉石和石榴石以及它们之间的平衡共生关系。各主要造岩矿物的化学成分及相互关系都说明桦旬杂岩的变质作用高峰达麻粒岩相。文中用斜方辉石-单斜辉石、石榴石-黑云母、石榴石-普通角闪石、石榴石-斜方辉石和石榴石-斜方辉石-斜长石-石英等矿物对和矿物组合作了变质作用温度、压力估测。桦甸杂岩的变质作用温压条件约为6.4—7.1kbar,700—750℃,桦甸杂岩变质时的埋藏深度约25km,当时的地热梯度大约30℃/km。     

北京居民生活满意度的多层级定序因变量模型分析

传统经济学视角出发的个体生活满意度研究往往忽略了数据的嵌套性,多层级模型更适用于地理学中分析不同层级地理单元特征对个体生活满意度的影响。采用多层级定序因变量模型,以北京为例,研究居民生活满意度在城市内部街道和居住小区尺度内的异质性,并研究了高层级地理空间单元的属性特征对居民生活满意度的影响。结果表明,生活满意度在居住小区层级的异质性远高于街道层级,个体自身的社会经济属性对个体的生活满意度有显著影响,总的来说,高收入、老年人、北京户口居民的生活满意度更高。除个体属性特征以外,居住小区的类型是影响生活满意度的重要因素,商品房小区居民的满意度显著高于保障房和单位房小区居民。     

南极普里兹湾及邻近南大洋水体N_2O分布特征

利用中国第25、26次南极科学考察航次获得南极普里兹湾及邻近南大洋附近水样,采用顶空气相色谱法分析其中N_2O含量,结果表明普里兹湾陆架水体N_2O浓度较低,介于13.2―17.4 nmol·L~(-1),且呈现不饱和状态,饱和度异常值为-7%;而普里兹湾附近南大洋水体中N_2O浓度较高,介于15.5―23.3 nmol·L-1,除表面一层极薄的不饱和层外,中层至底层水体相对工业革命前大气浓度为高度过饱和状态。该区域N_2O的分布格局与复杂的水团特性和水文过程有密切关系。N_2O含量不饱和的普里兹湾陆架水(SW)和绕极深层流(CDW)混合下沉形成南极底层水(AABW),可能为温室气体N_2O提供向深层海洋输运的通路。这个过程为大气N_2O提供了一个汇的机制,使南极近岸水体成为大气N_2O的汇区。     

Agent-Based Modeling and Analysis of Hurricane Evacuation Procedures for the Florida Keys

The unique geography of the Florida Keys presents both high risk of hurricane landfall and exceptional vulnerability to the effects of a hurricane strike. Inadequate hurricane shelters in the Keys make evacuation the only option for most residents, but the sole access road can become impassable well in advance of a major storm. These extraordinary conditions create challenges for emergency managers who must ensure that appropriate emergency plans are in place and to ensure that an orderly exodus can occur without stranding large numbers of people along an evacuation route with inadequate shelter capacity. This study attempts to answer two questions: (1) What is the minimum clearance time needed to evacuate all residents participating in an evacuation of the Florida Keys in advance of a major hurricane for 92,596 people – a population size calculated based on the 2000 US Census population data, census undercounts, and the number of tourists estimated to be in the area? (2) If a hurricane makes landfall in the Keys while the evacuation is in progress, how many residents will need to be accommodated if the evacuation route becomes impassable? The authors conducted agent-based microsimulations to answer the questions. Simulation results suggest that it takes 20 h and 11 min to 20 h and 14 min to evacuate the 92,596 people. This clearance time is less than the Florida state mandated 24-h clearance time limit. If one assumes that people evacuate in a 48-h period and the traffic flow from the Keys would follow that observed in the evacuation from Hurricane Georges, then a total of 460 people may be stranded if the evacuation route becomes impassable 48 h after an evacuation order is issued. If the evacuation route becomes impassable 40 h after an evacuation order is issued, then 14,000 people may be stranded.