中国大都市区界定探讨——基于"五普"分县数据的分析

改革开放以来，中国城市化的快速发展为大都市区发展创造了条件，大都市区已成为我国城市化发展新的空间载体。对大都市区进行界定是大都市区研究的前提。本文提出以第五次人口普查数据为基础界定中国大都市区的简化方法，并对中国大都市区的发展情况进行了初步研究。     

典型岩溶流域不同地貌类型景观结构分析——以云南小江流域为例

利用2003年小江流域的TM影像，结合实地调查，再根据流域地质分布和地貌发育情况，将流域地貌类型划分为岩溶地貌和非岩溶地貌两个一级类型景观，在此基础上，根据地貌发育程度结合高程情况，将岩溶区又划分为6个岩溶景观，非岩溶地貌分为两个二级类型景观。应用景观生态学原理，并通过Fragstats 3．3软件在流域尺度上计算了一些相关指标。结果表明：岩溶区的景观生态特征总体上体现了其生态环境的特殊性和脆弱性，地表水资源溃乏，土层薄、土壤资源零星分布且易流失，造成未利用地面积大，石漠化现象严重，土地利用程度低的特点。非岩溶区景观生态由于耕地和林地占绝对优势，石漠化面积少，香农多样性指数和均匀度低，景观的异质性较低，结构较为简单。     

地方政府官方旅游网站营销功能实证分析

在线营销已成为信息时代目的地整体营销战略的重要组成部分,考察目的地营销网站的发展状况有助于目的地营销组织审视其在线营销活动。以中国内地31个省为例,将营销战略、信息服务、交易处理、技术支持和网站运营作为一级指标,对官方旅游网站的营销功能进行评估。结果表明,目前国内目的地营销网站功能已无显著地区差异,大部分网站处于信息提供的初级发展阶段,目的地营销战略实施、交易处理等功能尚需改进;地方官方网站营销功能的充分发挥有赖于各级政府的支持,目的地在线营销的发展必须与目的地整体营销战略相整合。     

2006年甘肃文县5.0级地震灾害损失评估

2006年6月21日在甘肃省文县发生MS5.0地震,造成了建筑物破坏及人员伤亡。在震后开展的地震现场考察与震害评估工作中,将灾区分为2个评估子区,完成了29个点的震害抽样调查工作,根据地震灾害损失评估系统EDLES2.5的要求建立了有关数据库,做出了经济损失评估,并针对灾害特点给出了灾区恢复重建的建议。     

华夏地块东南部地壳地震各向异性特征初步研究

本研究采用SAM剪切波分裂分析方法，使用福建区域数字地震台网记录到的（1999年01月～2003年12月）的波形资料，挑选符合剪切波窗口条件的记录，得到华夏地块东南部地区23°N～29°N，116°E～120°E）10个台站的剪切波分裂参数. 研究结果表明，该区域快剪切波平均偏振方向为NW109.4°±42.6°，慢剪切波平均时间延迟为2.5±1.5(ms/km)，快剪切波平均偏振方向对应该区的水平主压应力方向. 闽东台站NW方向的快剪切波偏振优势方向揭示了NW向的水平主压应力和NW走向断裂的构造意义. 两个闽西台站NE方向的快剪切波偏振优势方向与区域水平主压应力方向不一致，与NE走向的断裂一致，体现了局部构造和局部应力场的复杂性. 本研究证实，位于活动断裂上的台站的快剪切波偏振方向的优势方向与断裂走向一致，位于海边或岛上的台站的快剪切波偏振方向较为离散，主要是受到不规则表面地形和断裂交汇的影响. 慢剪切波延迟时间的空间分布特征，显示沿海地区慢剪切波延迟时间变化较大，而内陆地区则较为平缓.     

Geochemistry and spatial distribution of OIB and MORB in A’nyemaqen ophiolite zone: Evidence of Majixueshan ancient ridge-centered hotspot

The mafic volcanic association is made up of OIB, E-MORB and N-MORB in the A'nyemaqen Paleozoic ophiolites. Compared with the same type rocks in the world, the mafic rocks generally display lower Nb/U and Ce/Pb ratios and some have Nb depletion and Pb enrichment. The OIB are LREE-enriched with (La/Yb)N =5―20, N-MORB are LREE-depleted with (La/Yb)N = 0.41―0.5. The OIB are featured by incompatible element enrichment and the N-MORB are obviously depleted with some metasomatic effect, and E-MORB are geochemically intermediated. These rocks are distributed around the Majixueshan OIB and gabbros in a thickness greater than a thousand meters and transitionally change along the ophiolite extension in a west-east direction, showing a symmetric distribution pattern as centered by the Majixueshan OIB, that is, from N-MORB, OIB and E-MORB association in the Dur'ngoi area to OIB in the Majixueshan area and then to N-MORB, OIB and E-MORB assemblage again in the Buqingshan area. By consideration of the rock association, the rock spatial distribution and the thickness of the mafic rocks in the Majixueshan, coupled with the metasomatic relationship between the OIB and MORB sources, it can be argued that the Majixueshan probably corresponds to an ancient hotspot or an ocean island formed by mantle plume on the A'nyemaqeh ocean ridge, that is the ridge-centered hotspot, tectonically similar to the present-day Iceland hotspot.     

Application of <Superscript>137</Superscript>Cs fingerprinting technique to interpreting sediment production records from reservoir deposits in a small catchment of the Hilly Loess Plateau,China

According to variations of 137Cs and clay contents, 44 flood couplets were identified in a profile of reservoir deposit with a vertical length of 28.12 m in the Yuntaishan Gully. Couplet 27 at the middle of the profile had the highest average 137Cs content of 12.65 Bq kg-1, which indicated the 1963s' deposits, then 137Cs content decreased both downward and upward in the profile. The second top and bottom couplets had average 137Cs contents of 2.15 Bq kg-1 and 0.92 Bq kg-1, respectively. By integrated analysis of reservoir construction and management history, variations of 137Cs contents over the profile, sediment yields of flood couplets and rainfall data during the period of 1958-1970, individual storms related to the flood couplets were identified. 44 floods with a total sediment yield of 2.36×104 m3 occurred and flood events in a year varied between 1 and 10 times during the period of 1960-1970. 7-10 flood events occurred during the wet period of 1961-1964 with very wet autumn, while only 1-2 events during the dry period of 1965-1969. Average annual specific sediment yield was 1.29×104 t km-2 a-1 for the Yuntaishan Gully during the period of 1960-1970, which was slightly higher than 1.11 ×104 t km-2 a-1 for the Upper Yanhe River Basin above the Ganguyi Hydrological Station and slightly lower than 1.40 ×104 t km-2 a-1 for the nearby Zhifang Gully during the same period. Annual specific sediment yields for the Yuntaishan Gully were correlated to the wet season's rainfalls well.     

Pb and Th in settling particles in the western Northwest Pacific Ocean: Particle flux and scavenging

A mooring of three conical time-series sediment traps was deployed at two sites in the western Northwest Pacific Ocean for 9 months. Total mass fluxes and activities of ²¹⁰Pb and ²³⁰Th were determined for the settling particles to elucidate their scavenging and transport processes. Sediment samples also were analyzed for ²¹⁰Pb activities. Total mass fluxes, ²¹⁰Pb fluxes and ²³⁰Th fluxes showed large seasonal variations and their weighted mean fluxes tended to increase with depth, with an especially large increase near-bottom. The ratios of the observed ²¹⁰Pb fluxes to the ²¹⁰Pb deficiency fluxes in the upper traps at the two sites were only 0.02 and 0.12, and were attributable to advective export of ²¹⁰Pb from the surface waters. Those ratios in the near-bottom traps ranged between 1.22 and 2.63. This suggests that these high ratios are due to effective particle scavenging, large lateral ²¹⁰Pb import and input of resuspended particles that have not become incorporated into the sediments. The mean total ²³⁰Th fluxes at the near-bottom traps were 4.2–6.7 times higher than that expected from production in the overlying water column. The ²¹⁰Pb activities in the surficial sediments were much lower than those in the near-bottom traps. The ²¹⁰Pb accumulation rates estimated from the excess ²¹⁰Pb inventory in the sediment column were 40–70% higher than the mean ²¹⁰Pb fluxes at the near-bottom traps. The ratios of the ²¹⁰Pb accumulation rates to the ²¹⁰Pb deficiency fluxes at the near-bottom traps ranged between 2.0 and 3.7. The high fluxes of particulate ²¹⁰Pb and ²³⁰Th at the near-bottom traps reflected a combination of enhanced scavenging of dissolved nuclides and the lateral redistribution of particulate matter by downslope and alongshore transports. However, it was not possible to discriminate among the various processes contributing to high nuclide fluxes.     

The deep-lake deposit in the Upper Triassic Yanchang Formation in Ordos Basin, China and its significance for oil-gas accumulation

The deep-lake facies of the Yanchang Formation represents a large outflowing lake basin in the Ordos area. Its deposition can be divided into four stages lake genetic and expanding stage, peak stage, inversion stage and dying stage. All the stages are obviously consistent with the evolution of depositional environment and the paleoclimate in the region. The study indicates that the lake basin has evolution fluctuations from highstand to lowstand for four times in its evolution history, and the deposition center of the lake has not obviously moved, staying along the Huachi-Yijun belt. The deep lake sedimentary system mainly consists of deep water deltas and turbidite fans during the entire evolution course of the lake basin in the Late Triassic. The former mainly developed on the slope of steep shore of the delta in the early period of the deep-water expansion and gradually experienced a big shift from deep-water deltas to shallow-water platform delta. And the latter appeared almost in all the above stages and had two types of turbidite fans, slope-moving turbidite fans and slump turbidite fans. The slope-moving turbidite fans have relatively complete facies belts overlapping one another vertically and consist of the slope channel of inter fans, the turbidite channel, inter turbidite channel and turbidite channel front of middle fans and outer fans (or lakebottom plain). However, the slide-moving turbidity fans are formed in the deep lake with their microfacies difficult to be distinguished, and only the center microfacies and edge microfacies can be determined. The two types of the turbidity fans are similarly distributing in the near-root-slope and far-root-slope regions. The deep-lake deposition governs the distribution of the hydrocarbon and reservoir, while the slope-moving turbidite fans are excellent reservoirs for oil-gas exploration due to their great thickness, widespread distribution and accumulation properties.