SHRIMP Geochronology of Volcanics of the Zhangjiakou and Yixian Formations, Northern Hebei Province, with a Discussion on the Age of the Xing＇anling Group of the Great Hinggan Mountains and Volcanic Strata of the Southeastern Coastal Area

A zircon U-Pb geochronological study on the volcanic rocks reveals that both of the Zhangjiakou and Yixian Formations, northern Hebei Province, are of the Early Cretaceous, with ages of 135-130 Ma and 129-120 Ma, respectively. It is pointed out that the ages of sedimentary basins and volcanism in the northern Hebei -western Liaoning area become younger from west to east, i. e. the volcanism of the Luanping Basin commenced at c. 135 Ma, the Luotuo Mount area of the Chengde Basin c. 130 Ma, and western Liaoning c. 128 Ma. With a correlation of geochronological stratigraphy and biostratigraphy, we deduce that the Xing‘anling Group, which comprises the Great Hinggan Mountains volcanic rock belt in eastern China, is predominantly of the early-middle Early Cretaceous, while the Jiande and Shimaoshan Groups and their equivalents, which form the volcanic rock belt in the southeastern coast area of China, are of the mid-late Early Cretaceous, and both the Jehol and Jiande Biotas are of the Early Cretaceous, not Late Jurassic or Late Jurassic-Early Cretaceous. Combining the characteristics of the volcanic rocks and, in a large area, hiatus in the strata of the Late Jurassic or Late Jurassic-early Early Cretaceous between the formations mentioned above and the underlying sequences, we can make the conclusion that, in the Late Jurassic-early Early Cretaceous, the eastern China region was of high relief or plateau, where widespread post-orogenic volcanic series of the Early Cretaceous obviously became younger from inland in the west to continental margin in the east. This is not the result of an oceanward accretion of the subduction belt between the Paleo-Pacific ocean plate and the Asian continent, but rather reflects the extension feature, i.e. after the closure of the Paleo-Pacific ocean, the Paleo-Pacific ancient continent collided with the Asian continent and reached the peak of orogenesis, and then the compression waned and resulted in the retreating of the post-orogenic extension from outer orogenic zone to inner part (or collision zone). The determination of the eruption age of the volcanics of the Zhangjiakou Formation definitely constrains the switch period, which began in the Indosinian and finished in the Yanshanian, that is, 140-135 Ma. The switch is concretely the change from the approximate E-W Paleo-Asian tectonic system to the NE to NNE Pacific system, and the period is also the apex of a continent-continent collision and orogenesis of subduction, being consumed and eventually disappearing of the Paleo-Pacific ancient continent, and all the processes commenced in the Indosinian. While the following post-orogenic large-scale eruption in the Early Cretaceous marks the final completeness of the Paleo-Pacific structure dynamics system.     

张家口市水资源安全风险空间分异研究

张家口市地处生态脆弱的农牧交错地带,地表水资源匮乏,地下水超采严重,可利用的地表水资源有限。同时,张家口市又处于京津冀协同发展中的水源涵养区,其水资源安全对于整个京津冀至关重要。根据水资源安全风险大小进行水资源分区管理和决策工作意义重大。本文在遵循科学性、可比性、可操作性和数据可获取性原则指导下,构建水资源安全风险评价指标体系,利用层次分析法求取指标权重,采用数理统计和3S技术空间分析获取张家口市基于水资源分区的以县域为单位的多源数据,进行数据归一化处理和加权水资源安全风险评价,结果表明:张家口市水资源安全风险在地貌单元与县域行政尺度上和在流域尺度上分异明显。坝上高风险区面积较大,但高风险极端值在坝下市辖区;流域尺度上水资源安全高风险区分布在内陆河流域和永定河流域,所辖的滦河流域、潮白河流域、大青河流域水资源安全风险值呈现由北向南降低的趋势。坝上偏西偏北区域,"孕灾环境脆弱性"对水资源安全风险的贡献率最大,坝下农区农业用水虽然会挤占其它产业发展和生态用水空间,在水资源禀赋不足的条件下,市辖区城市人口的集聚和工业经济的发展造成的水资源数量短缺和水环境污染所引发的水资源安全风险更大。张家口市水资源安全风险的空间分异研究,可为农牧交错带水资源安全风险分区管理和决策工作提供重要科学参考。     

张家口获3亿元矿山治理资金

本刊讯（李亚楠）河北省张家口市国土资源局积极组织申报下花园矿山地质环境治理项目,获得国务院审批。日前,该项目3亿元专项治理资金,已到位1亿元,近期即可开工建设。近年来,为加快我国重点区域矿山地质环境治理,财政部、国土资源部计划用3年时间,重点支持资源枯竭城市的矿山地质环境治理。     

Change of Ecological Footprint and Analysis of Ecological Sustainability —— Taking Zhangjiakou City as an Example

This paper researches the ecological sustainability of Zhangjiakou City, Hebei Province, China, using the ecological footprint model. According to the study we find that Zhangjiakou City was in the situation of ecological deficit from 1990 to 2000 and the deficit had the enlarging tendency. In 1990 the per capita ecological footprint was 0.964 and the per capita ecological capacity was 0.518, thus it can be calculated that the per capita ecological deficit was –0.446. However in 2000, the per capita ecological footprint increased to 1.068, at the same time the per capita eco- logical capacity decreased to 0.471, then the per capita ecological deficit in 2000 was –0.597. Furthermore, this paper studies the ecological sustainability of the city from the changes of the ecological footprint of per 10,000 yuan GDP and the productivity of ecological system. Finally the authors point out the shortage of the model and the way to improve it.     

京津冀不能再分灶吃饭 京津冀一体化发展论坛在崇礼召开 柳忠勤出席并主持开幕式

本刊讯8月16日．第三十二次中国科技论坛——京津冀一体化发展沦坛在河北省张家口市崇礼县召开。中国国土经济学会副理事长兼秘书长、研究员柳忠勤出席并主持开幕式,北京、天津、河北三地专家学者共议京津冀一体化协同发展。     

宣化、张家口：城市的兴衰

为什么张家口这座小小的城堡,会在今天发展成一座占地广大的地级市,而宣化却从一座府级城市下降为张家口下辖的一个区？ 带着疑问,我从北京出发,前往宣化和张家口一探究竞。 一座城市的地位和命运,经常会发生戏剧性的变化。宣化,号称“京西第一府”,在明代不仅是长城沿线的“九边重镇”之一,还是朱元璋之子谷王朱撼和万全都司（相当于省军区）的驻地。而张家口,最初只是万全都司属下一个默默无闻的小城堡。时光流转数百年,张家口不断扩张,到了20世纪,竟反将它曾经的“顶头上司”宣化“一口吞了下去”。如今,张家口上升为地级市,而宣化已经下降为张家口市所属的一个区。     

张家口市煤炭资源现状与勘查战略研究

张家口市资源开发程度偏高．后备资源及可供建井的基地严重匮乏,衰老矿井逐年增多,给今后煤炭工业的可持续发展带来了困难。在全面总结全市各含煤区的内、外部条件及勘查利用情况后认为,目前该市的的勘查程度结构不尽合理．面临着探采严重失调的被动局面,因而提出了继续加强煤田地质基础研究工作、加强老矿区外围及深部勘查工作、加强北部地区普查找煤工作及南部找煤工作、加强煤层气资源勘查及开发利用的试验研究工作等对策．为今后的煤炭地质勘查工作指明了方向。     

征地无小事 事事民为先

2003年对张家口市国土资源局宣化分局来说，是不同寻常的一年。丹拉高速公路工程、河北福田重工机械工程、宣化污水处理厂工程，都是国家、省重点项目。由于工期紧，征用地数目大，拆迁范围广，各项补偿费用多，分局的同志们加班加点，忘我工作，做到了依法行政，文明执法，秉公办事，执政为民，在平凡的工作岗位上认真践行”三个代表”重要思想，圆满完成了三大工程项目的征地拆迁、组卷报批和各项补偿工作，保证了工程项目顺利开工，受到了上级主管部门和区政府及当地群众的一致好评。     

张家口市国土资源系统首期新闻写作培训班圆满结束

2004年12月7日，张家口市国土资源系统首期新闻写作培训班在赤城开班。培训班上，省国土资源厅宣传中心主任刘扬正等分别对新闻写作的基础理论、新闻宣传的特点、新闻写作的技巧以及通讯员应具备的素质进行了深入浅出的讲解。通过培训，提高了学员们对新闻写作的认识，激发了学员们的写作热情，为进一步做好国土新闻宣传工作起到了积极的推动作用。