2021年2月13日日本福岛Mj7.3级地震潜在破坏区快速估计

基于2021年2月13日日本福岛M_j7.3级地震加速度记录,离线模拟了阈值预警方法在此次地震中快速估计潜在破坏区的表现。结果显示,该方法能够在台站P波触发后3s就快速对台站及其周边区域进行地震破坏性判断,同时估计的潜在破坏区域也基本与美国地质调查局（USGS） ShakeMap震后实测VII度以上区域吻合,展示了该方法在此次地震中运用的可行性;然而该方法没有对处在震后实测VII度以上区域内的宫城县南部沿海以及福岛县小部分东北区域给出准确的潜在破坏区判断,这一估计偏差为该方法的适应性研究以及下一步优化提供了参考。     

Geologic age of the lower Josoji Formation,Shimane Peninsula,Southwest Honshu,Japan: Implications for an abrupt change to deep-water during the earlier opening stage of the Japan Sea

The lower part of the Josoji Formation, Shimane Peninsula, contains clues for figuring out changes in deep-water characteristics during the opening of the Japan Sea. The foraminiferal assemblage includes early to middle Miocene biostratigraphic index taxa such as planktonic foraminiferal Globorotalia zealandica and Globorotaloides suteri. The occurrence of these two species, together with the absence of praeorbulinids, suggests that the lower part of the Josoji Formation is assigned to the top of planktonic foraminiferal Zone N7/M4 (16.39 Ma). The benthic foraminiferal assemblage, which is characterized by Cyclammina cancellata and Martinottiella communis, clearly suggests that the lower Josoji Formation was deposited at bathyal depths, and that it developed in association with the abrupt appearance of deep-sea calcareous forms. Such bathyal taxa are the main constituents of the Spirosigmoilinella compressa–Globobulimina auriculata Zone of the Josoji Formation and also of the Gyrodina–Gyroidinoides Zone at Ocean Drilling Program Site 797 in the Japan Sea. The base of these benthic foraminiferal zones can be correlated with the base of the nannofossil Sphenolithus heteromorphus Base Zone (= CNM6/CN3); thus, its estimated age is 17.65 Ma. This biostratigraphic information suggests that the lower Josoji Formation was deposited from shortly before 17.65–16.39 Ma in upper limit age. Evidence that fresh to brackish and shallow-water basins formed in the rifting interval of 20–18 Ma in the Japan Sea borderland suggests that the abrupt appearance of deep-sea calcareous foraminifera occurred about 1 my earlier in this area than in other sedimentary basins and suggests that a significant paleoceanographic change occurred in the proto-Japan Sea at 17.65 Ma.     

Charge exchange in massive star‐forming regions

As a result of feedback from massive stars, via their intense winds and/or supernova explosions, massive star‐forming regions are entirely filled with hot, X‐ray emitting plasmas, which escape into the ambient ISM. As shown recently by Townsley et al. for several “extreme” cases (Carina, M17, NGC 3576, NGC 3603, 30 Dor), by way of large Chandra ACIS mosaics, extra, non‐thermal emission lines are present on top of the standard lines emitted by hot plasmas. Some of them are very close to lines characteristic of charge‐exchange reactions between the hot plasma and the cold surrounding material, suggesting that this mechanism operates on large spatial scales (several 10 pc) in star‐forming regions in general. The connection with starburst galaxies is briefly mentioned, and it is pointed out that supernovae interacting with molecular clouds may also provide a good environment to look for charge exchange processes (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

遥感卫星数据产品分类分级规则研究

随着遥感卫星应用的发展,多源、多时相、多尺度以及不同类型遥感卫星的数据综合集成应用以及与地面观测信息集成,对遥感信息产品进行深度开发利用正在成为遥感应用的重要趋势。目前不同国家和地区、不同系列的遥感卫星数据产品分别采用不同的分类分级方案,难以适应多源、多系列地理空间信息整合应用的需求。本文从遥感应用对遥感卫星数据产品分类分级的需求出发,分析了目前主要遥感卫星的产品系列及其数据产品分类分级规则,参考了正在研究的相关国际标准,遵循系统性、科学性、完整性、兼容性、可操作性和可扩充性原则,研究提出了中国遥感卫星数据产品分类分级的规则。该规则以卫星载荷采用的遥感探测光谱特征及其数据获取方式作为分类依据,以卫星遥感数据的处理水平作为分级依据,建立统一的遥感卫星数据产品的分类分级体系。该规则与正在研究制订的相关国际标准保持一致,不但覆盖目前广泛应用的各类遥感卫星数据产品,而且能方便地建立与现有遥感卫星数据产品分类分级方案的映射关系,并且对未来的数据产品的分类分级留有比较充分的可扩充性,为遥感卫星数据产品分类分级指标体系的研究和相关国家标准的研制提供了依据。     

重庆市地质灾害监测预警信息系统建设与应用

文章从系统建设需求、系统构架、功能组成及数据集成建设、系统展示与应用六个方面介绍了重庆市地质灾害监测预警系统建设与应用。系统研发过程中利用了计算机网络、通信和3S技术,按照统一的标准和规范要求建设,旨在搭建一个重庆市地质灾害防治信息与监测预警平台,实现地质灾害防治网络化运作模式,提升地质灾害防治日常管理、监测预警、决策支持和应急处置能力,为重庆地质灾害防治提供信息服务及决策服务。     

张衡地动仪的诞生

地动仪的诞生有着深厚的历史背景,本文旨在探讨张衡科学思想的形成过程和物质基础.张衡生活在东汉文化发展的顶峰时期,“观察异象、辨别凶吉”的朴素愿望是研制地动仪的原始动力.作者追溯了当时的历史背景、张衡的学术历程、地动仪的问世过程,分析了东汉早期的地震活动、古代的地震观念和灵台科学活动的特点.指出地动仪的研制起步于公元128年,张衡基于感性认识升华出两个地震概念——地震的位置可按方位判断、地震和地裂必须加以区别,这使地动仪的研制有了明确的技术追求.仪器制作上,张衡崇尚“制器尚象”的原则.地动仪的测震原理模仿了悬挂物(即天然验震器)对地震的反应,技术实现上借鉴了门闩类的触发机构,还通过龙首吐丸的方式留下了发生地震的物质证据,这3个关键问题的解决成就了公元132年地动仪的问世和134年的成功验震,构成他科技创新的完整内容.地动仪的发明深化了人类对自然规律的认识,对当时的东汉及其后世界文化的发展具有积极意义.     

ENERGY SOURCES FOR EVAPORATION ON TROPICAL ISLANDS

The sources of energy for evaporation on tropical islands were explored by studying 49 lowland sites in the Hawaiian Islands with concurrent pan evaporation and solar radiation measurements. The Priestley-Taylor (1972) method was used to quantify the contribution of solar radiation in evaporation and the residual term between estimated and measured evaporation was attributed to heat advection. Pearson correlation coefficients between monthly measured and estimated evaporation (using solar radiation data) were greater than 0.95 at 26 of the sites, 0.90 for 37 sites, and 0.80 at 46 of the 49 sites used in the study. As expected, solar radiation supplies the bulk of the energy absorbed by evaporation at low elevations in Hawaii. However, a pattern of negative advection in summer and positive advection in winter from the surrounding ocean modifies the monthly evaporation values. For the 20 sites showing the greatest oceanic influence, departures ranged, on average, from +0.84 mm/day in November to -0.71 mm/day in June. This onshore advection corresponds to the seasonal lag in sea surface temperatures. At inland and wet lee sites, the effect of advection from oceanic sources diminishes. At dry lee sites, strong positive advection is evident in summer and autumn, enhancing evaporation by up to 2.8 mm/day. [Key words: evaporation, energy, tropical islands, radiation, advection]     

Combining spatial transition probabilities for stochastic simulation of categorical fields

Categorical spatial data, such as land use classes and socioeconomic statistics data, are important data sources in geographical information science (GIS). The investigation of spatial patterns implied in these data can benefit many aspects of GIS research, such as classification of spatial data, spatial data mining, and spatial uncertainty modeling. However, the discrete nature of categorical data limits the application of traditional kriging methods widely used in Gaussian random fields. In this article, we present a new probabilistic method for modeling the posterior probability of class occurrence at any target location in space-given known class labels at source data locations within a neighborhood around that prediction location. In the proposed method, transition probabilities rather than indicator covariances or variograms are used as measures of spatial structure and the conditional or posterior (multi-point) probability is approximated by a weighted combination of preposterior (two-point) transition probabilities, while accounting for spatial interdependencies often ignored by existing approaches. In addition, the connections of the proposed method with probabilistic graphical models (Bayesian networks) and weights of evidence method are also discussed. The advantages of this new proposed approach are analyzed and highlighted through a case study involving the generation of spatial patterns via sequential indicator simulation.     

基于 GIS 的天津市突发性地质灾害预警预报系统设计与实现

基于地质灾害的多样性及其变化的随机性和非稳定性特点,本文综合利用数学算法和GIS技术,设计了地质灾害预警模型,分析了诱发地质灾害的地形、地貌、气象、水文等几方面的因素,应用地质灾害显式统计预警的基本原理,并通过确定性系数模型(CF)综合分析了天津市地质灾害分布与地质环境基础因素的关系,更好的修订了我市地质灾害预警预报模型.实践证明,应用基于GIS 的地质灾害预警预报系统已在我市近几年的地质灾害气象预警预报中不断完善,预警预报精度得到提高,防灾减灾效果明显,对保护人民生命财产安全发挥了重要作用.     

采煤塌陷区整治方法的评价与选择

采煤塌陷是煤矿城市所面临的一个重要问题,针对这个问题,社会各界专家提出了不同的整治方法,文章基于这些已有的方法,提出了定量化的采煤塌陷区整治方法评价指标体系,并将其运用到关店乡总体规划中对丁集煤矿采煤塌陷区整治方法的选择上,从而为规划的编制提供一定的理论依据.