A STUDY ON RECESSION MECHANISM AND REJUVENATION WAYS OF THENORTHEAST OLD INDUSTRIAL BASE

I.MAINRECESSIONCHARAgyERIarICSINTHENOn~~OafIanUSrnIAnSince1990,thenortheastoldindustrialbasehaslandedinabaddevelopingpredicament.Ithasslowdevelopment,exhaustedgrowthandaireconomicresult.Thepeoplecallit"theNortheastPhenomenon"(Kewen,1992).Themaincharacteristicsareasfollows:(1)TheeconomyinthenortheastoldindustrialbaseincreasedslowlyandthesituationoftotaloutputinthewholecountryhascomedO~obviously.From1989to1991,theincreasingspeedsofgross~ialproductinLiaoning,JinnandHeilongjiang…     

THE MIRE IN NORTHEAST OF CHINA

The northeast region is one of the principal mire distribution regions in China. According to the process of peat formation and accumulation , middle geomorphology type controlling water source supplement and the plant cover, 2 types, 10 subtypes and 27 mire bodies are divided. The mire area decreases gradually from north to south. There is more peat mire in the mountain and there is mainly gley mire without peat in the plain. The paper also explains the mire types in the principal mire distribution region and the utilization of mire in the fields of agriculture, forest, animal husbandry. The mire is a wetland ecosystem. It can reserve a lot of water, adjust rivers, humidify air. Thereby , attention must be paid to protecting ecological balance in the process of reclaiming mire and the mire protection.     

东北地区地貌信息熵与地震构造

利用侵蚀流域的地貌信息熵理论定量研究了东北地区的构造活动和区域稳定性，结果表明，熵值小于０．２的区域与现代构造活动的区域相一致，熵值的高梯度带及其走向畸变部位与大地震的位置具有某种对应关系。总体分布状态与新活动较强的构造格架可能有某种成因联系．     

一次罕见的左移超级单体风暴的特征

利用白山多普勒天气雷达、常规观测和地面加密观测资料,对2012年7月2日发生在吉林省南部的一次左移超级单体风暴进行了研究。结果发现,此次天气过程发生在深厚东北冷涡的东南象限、超强高空急流核附近的北侧,且低空风垂直切变不强、对流有效位能不大;低空有较强的暖平流,并存在一个西南—东北走向的风切变区;低空辐合、高空辐散、位于露点锋附近以及高空急流核的存在为有利于的对流发展的重要因素。在风暴发生发展过程中,始终有一个中-β尺度反气旋环流(尺度为120 km)相伴随,其旋转半径由高到低逐渐增加并在东南偏南方向被拉伸为椭圆型结构,风暴发生在该环流的西北象限的西南偏南气流之中,并具有钩状回波、弱回波区、反中气旋等超级单体所具有的特征。反中气旋出现在对流风暴发展的旺盛期,旋转半径从低层到高层逐渐增加。在风暴经过地区出现了冰雹、强降温、瞬时大风等天气现象和气象灾害。     

西秦岭北缘-拉脊山两侧地貌差异及地貌演化

为了解西秦岭北缘-拉脊山两侧的地貌差异及其发育机制,利用DEM数据结合地质数据,提取局部地形起伏并绘制高程带状剖面图,定量化揭示了西秦岭北缘-拉脊山东西两侧地貌结构;在此基础上,统计了两侧新生代不同时期地层砂岩的高程像元众数,并进行了对比分析;通过对已知地质资料的提取和归纳,对比了西秦岭北缘-拉脊山断裂两侧新生代盆地地层岩性及沉积相.结果表明,界限以东新生代地层呈现地层年代越老高程越高的趋势;界限以西则呈现古近纪至新近纪地层越新高程越高、第四纪地层高程最低的特征.这种地层发育规律体现了西秦岭北缘-拉脊山两侧的地貌演化过程存在差异,即东侧水系发育时间早于西侧,地貌接受侵蚀的时间较长.同时,也从侧面反映了东、西两侧构造活动强度与时间的不一致性,古近纪以来东侧构造演化具有自SW向NE逐渐扩展的趋势;而西侧构造演化更为复杂,体现在新生代以来不同断裂带隆升历史的不一致性以及在较强的挤压应力及较弱剥蚀共同作用下的增生过程.     

东北地区M≥5.0地震前中等地震集中活动的震兆研究

定义了描述东北地区中等地震活动增强的3个参量E、T和R,并对东北地区11次M≥5.0地震进行了统计分析.结果显示,东北地区地震活动具有明显的区域性特点:辽宁地区和嫩江断裂以西地区M≥5.0地震前均存在4级地震集中活动的现象,且预期的5级以上地震大部分发生在最近1次4级地震后的半年内;嫩江断裂以东地区5级地震前没有中等地震集中活动的特征.ETR方法在中等地震活跃后判定未来5级地震的震中时具有一定的指示意义.     

Glacier Peak and mid-Lateglacial Katla cryptotephras in Scotland: potential new intercontinental and marine-terrestrial correlations

Using contiguous high resolution sampling methods, we report the detection of a Glacier Peak volcanic ash from North America in Lateglacial Interstadial lake sediments in western Scotland. It occurs in close proximity to the Icelandic Borrobol and Penifiler tephras, but is distinguishable by its rhyolitic major-element composition that is consistent with the earliest set G layer, one of a number of mid-Interstadial Glacier Peak eruptions dated between 13.71 and 13.41 cal ka bp. Another cryptotephra layer present in these same Interstadial sediments has a rhyolitic composition consistent with the Icelandic Katla source. However, it is in a stratigraphic position below the widespread mid-Lateglacial Stadial Vedde Ash from Katla, which is also present in these cores. The Katla layer is stratigraphically well defined, suggesting primary airfall, and is compositionally similar to a mid-Interstadial rhyolitic tephra reported from a North Atlantic marine sequence south of Iceland dated to ~13.6 ka. The detection of Glacier Peak G in the European tephrostratigraphy will permit direct high-precision correlation of mid-Interstadial palaeoenvironments between North American and European terrestrial sequences. Any correlation between the new Katla layer and similar marine layers remains provisional, though if verified would permit similar correlation between North Atlantic marine and European terrestrial records.     

东北地区资源型城市经济结构转型研究

东北地区是以耗竭大量自然资源为代价的外延型经济发展典型地区。经过近百年来的开发．区域资源趋于枯竭．资源型城市发展面临着一系列矛盾和问题。东北地区资源型城市问题和矛盾是长期积累形成的．有着特定的时代背景和体制原因。本文分析了东北资源型城市所面临的问题．阐明了其经济衰退的机制和问题的成因．提出了今后东北资源型城市发展的四种模式——综合性发展模式、主导产业转型模式、培育接续产业模式、资源带动发展模式,论述了资源型城市实现经济结构转型和可持续发展所必须破解的三大难题——产业结构调整、劳动力就业、生态环境整治．并提出相应的对策和建议。     

滇东北MS≥5.0地震前地下流体异常特征与2014年云南鲁甸6.5级地震研究

在对滇东北地区地下流体观测资料进行综合评估的基础上,选择评估达到Ⅰ、Ⅱ类的观测资料,采用日值、五日均值、旬均值、相关矩平、K-L拟合分析、CF分析等方法,对2003～2012年以来滇东北地区的5组MS≥5.0地震进行震例回顾总结.归纳震前该区地下流体前兆异常的时空演化特征,发现前兆异常数量在时间上具有阶段性,异常项数在震前6个月开始增多,震前3个月达到最大值,临震前1个月部分异常转折结束,异常数量出现降低;异常在空间演化上具有震前3个月向震中收缩的特点.80％的震例表明震中距100 km范围内的观测点异常比例远高于100 km范围外的观测点异常比例.将结果外推应用于2014年8月3日鲁甸6.5级地震,发现他们具有较好的一致性,表明滇东北地区MS≥5.0地震前地下流体的异常特征具有普适性.     

Asymmetrical river valleys in response to tectonic tilting and strike‐slip faulting,northeast margin of Tibetan Plateau

The northeast margin of the Tibetan Plateau, a particularly important area to understand the mechanism of plateau formation, is characterized by large transpressional arcuate faults. There is debate on the amount of Quaternary sinistral displacement on the major Haiyuan Fault. Previously unrecognized systemic asymmetrical valleys have developed between the Haiyuan and Xiangshan faults. Southeast tilting and sinistral displacement on the northeast side of the Haiyuan Fault resulted in southeast migration of large rivers and asymmetrical widening of their valleys, leaving a systematic distribution of tilted strath terraces along their northwest sides. Where asymmetrical widening created by tilting kept pace with sinistral displacement, rivers have not been deflected, and the increase in valley width downstream from the fault should equate to total lateral displacement since river formation (e.g. Yuan River, a 7 km asymmetrical valley with a c. 2.2 Ma paleomagnetic age). Where river deflection and asymmetrical valley growth are coeval, valley width is less than total horizontal displacement (e.g. Hebao River, a c. 2.1 km asymmetrical valley with c. 2 km deflection). All rivers north of the Haiyuan Fault converge to cut across the Xiangshan Mountains as a gorge. Northeast thrusting of the upthrown side of the Xiangshan Fault has resulted in degradation and related strath terrace formation as the valleys asymmetrically widened. A probable earthquake‐induced landslide caused by movement on the Xiangshan Fault in latest Pleistocene blocked the gorge causing aggradation along all rivers and their tributaries. Deposition terraces were formed after the landslide dam was breached. Together with previous research on the Xiangshan Fault, it is concluded that there has been c. 7 km of Quaternary sinistral displacement on the Haiyuan and Xiangshan faults along the northeast margin of the Tibetan Plateau since the formation of rivers that intersect them. Copyright © 2014 John Wiley & Sons, Ltd.