西南山区遥感蚀变异常信息提取综合研究——以云南酒房地区为例

遥感蚀变异常信息现已广泛的用于矿产勘查,并在一些地区取得了良好的效果,但由于西南地区地形地貌复杂,地表覆盖严重,给遥感蚀变异常提取带来了很大的困难。如何因地制宜的进行西南地区遥感蚀变异常信息提取工作是我们面临的重要问题。本文以云南酒房地区为例,探讨了西南地区遥感蚀变异常信息提取中遇到的主要问题,结合地形地貌特征进行干扰信息的去除;结合地质背景、成矿条件进行遥感异常信息提取类别的选择;以及结合化探异常进行异常信息后处理等几个方面完善了异常提取的方法,使得遥感蚀变异常提取方法更加具有针对性,通过与现有地质资料的分析,证明本文异常提取方法可以有效的提取西南地区与矿相关的蚀变信息。     

Growth of normal faults in multilayer sequences: A 3D seismic case study from the Egersund Basin,Norwegian North Sea

We investigate the structural style and evolution of a salt-influenced, extensional fault array in the Egersund Basin (Norwegian North Sea) through analysis of 3D reflection seismic and well data. Analysis of fault geometry/morphology, throw distribution and syn-kinematic strata reveal an intricate but systematic style of displacement and growth, suggesting an evolution of (1) initial syn-sedimentary fault growth contemporaneous with salt mobilization initiated during the Late Triassic, (2) cessation of fault activity and burial of the stagnant fault tips, and (3) subsequent nucleation of new faults in the cover above contemporaneous salt re-mobilization initiated during the Late Cretaceous, with downward propagation and linkage with faults. Stage 3 was apparently largely controlled by salt mobilization in response to basin inversion, as reactivated faults are located where the underlying salt is thick, while the non-reactivated faults are found where salt is depleted. Based on the 3D-throw analyses, we conclude that a combination of basement faulting and salt (re-) mobilization is the driving mechanisms behind fault activation and reactivation. Even though the sub- and supra-salt faults are mainly geometrically decoupled through the salt, a kinematic coupling must have existed as sub-salt faults still affected nucleation and localization of the cover faults.     

西藏尼木地区遥感数据地温反演与地热异常预测

为探明西藏尼木地区地热资源的空间分布及指导该区地热资源的勘探与开发,选取2010年1月21日与2月22日的Landsat 5TM数据,基于单波段的单窗算法进行地表温度反演,并利用ArcGIS软件分析了地表温度、已有地热异常点、构造及人类活动之间的关系,对该区潜在的地热异常进行预测。结果表明,地表温度分别为：-21.75～40.65 ℃,-18.95～46.45 ℃,二者进行对比分析表明反演结果符合实际且结果可靠。依据遥感数据地温反演结果,发现区内温度异常区比背景区高10 K以上,研究区存在未被发现的隐伏断层及地热活动异常信息,由此划分出21个潜在地热异常区。结论认为位于亚东—谷露与雅鲁藏布江缝合带交汇区的尼木地区地热异常特征明显,勘探开发前景广阔;在高寒缺资料区基于遥感单窗算法进行温度反演,可以有效提取地热异常信息,帮助预测具有开发前景的地热异常区,并进一步识别圈定具有勘探意义的靶区。     

西藏尼木地区遥感数据地温反演与地热异常预测

为探明西藏尼木地区地热资源的空间分布及指导该区地热资源的勘探与开发,选取2010年1月21日与2月22日的Landsat 5TM数据,基于单波段的单窗算法进行地表温度反演,并利用ArcGIS软件分析了地表温度、已有地热异常点、构造及人类活动之间的关系,对该区潜在的地热异常进行预测。结果表明,地表温度分别为： -21.75～40.65 ℃,-18.95～46.45 ℃,二者进行对比分析表明反演结果符合实际且结果可靠。依据遥感数据地温反演结果,发现区内温度异常区比背景区高10 K以上,研究区存在未被发现的隐伏断层及地热活动异常信息,由此划分出21个潜在地热异常区。结论认为位于亚东—谷露与雅鲁藏布江缝合带交汇区的尼木地区地热异常特征明显,勘探开发前景广阔;在高寒缺资料区基于遥感单窗算法进行温度反演,可以有效提取地热异常信息,帮助预测具有开发前景的地热异常区,并进一步识别圈定具有勘探意义的靶区。     

城市区域热辐射方向性研究进展

城市是陆地生态系统中极为重要的地表覆盖类型,把握其热辐射特征对于研究城市地表能量平衡和城市热岛具有积极的意义.相对于自然地表,城市区域表现出更为显著的热辐射方向特征,但这方面的研究直到近年来才开始发展起来.对城市区域的航空遥感和地表观测试验均揭示,城市区域热辐射方向性与太阳-地面目标-传感器几何关系、城市形态与结构、地面目标物理性质等密切相关.同时,为描述城市区域热辐射方向性,辐射温度三维格局模型、几何模型以及辐射传输模型都相继建立起来.从热辐射方向性的试验观测、模型建立及其与城市热岛关系等角度入手,系统回顾了城市区域热辐射方向性的研究进展,并对已经取得的研究成果进行了总结.最后,指出了尚待解决的问题及今后应着重研究的方向.     

Rocky desertification and its causes in karst areas: a case study in Yongshun County,Hunan Province,China

Rocky desertification, a process of land degradation characterized by soil erosion and bedrock exposure, is one of the most serious land degradation problems in karst areas, and is regarded as an obstacle to local sustainable development. It is well known that human activities can accelerate rocky desertification; however, the effects of climate change on rocky desertification in karst areas are still unclear. This study focused on the effects of temperature and precipitation changes and human activities on rocky desertification in karst areas to determine the impacts of climate change and human disturbances on rocky desertification. Areas of different level of rocky desertification were obtained from Landsat TM (1987) and Landsat ETM+ (2000) images. The results show that, although the total desertification area increased by only 1.27% between 1987 and 2000, 17.73% of the slightly desertified land had degraded to a moderate or intense level, 2.01 and 15.71%, respectively. Meanwhile, between 1987 and 2000, the air temperature increased by 0.7°C, and precipitation increased by 170 mm. Statistical results indicate that the increase in precipitation was caused by heavy rainfall. In addition, under the interactive influences of heavy rainfall and temperature, the average karst dissolution rate was about 87 m³ km⁻² a⁻¹ during the 14 years in the study area. Further analysis indicated that rocky desertification was positively related with the increase in temperature and precipitation and especially with the heavy rainfall events. Climate change accelerated rocky desertification in the karst areas. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

热红外遥感技术在江西寻乌地区地热勘查中的应用

热红外遥感是地热资源勘查中的常用技术,对江西寻乌地区的Landsat 8热红外影像采用单窗算法,根据MODIS影像计算大气水汽含量,并逐步获取反演参数,得到地表温度反演结果;利用MOD11_L2地表温度产品对结果进行对比分析,验证反演有效性。通过对已有地热资料和地质构造背景的研究,总结地热形成的有利构造条件,分析地表反演温度与已有地热及断裂构造之间的空间关系,建立地热异常区圈定依据,并剔除假异常,最终在研究区圈定了11个潜在地热异常区,为该区地热勘查提供依据。     

Use of geoprocessing in the study of land degradation in urban environments: the case of the city of São Carlos,state of São Paulo,Brazil

This paper presents a methodology for the geological engineering survey of land degradation in urban environments using both remote sensing and geoprocessing tools. The area under study was the city of São Carlos, state of São Paulo, Brazil (urban and expansion area). The data presented here were obtained from earlier studies, photointerpretation and geological engineering mapping. The Envi 4.1 software package was used to prepare the digital orthophotos that served as a reference base for the information. Orthorectification of the Ikonos image (PSM, 1 m) was done and compared with other orthophotos from studies of environmental degradation in urban areas. The evolution of land degradation processes was analyzed based on the photointerpretation of aerial photographs taken on different dates and using Ikonos image. This study allowed to conclude that most of the degradation occurring in the city has been caused by unplanned land occupation, in disregard of environmental conditions, resulting in environmental degradation and thus impacting the quality of life of the urban population.     

Application of remote-sensing data to groundwater exploration: A case study of the Cross River State, southeastern Nigeria

 The Cross River State, Nigeria, is underlain by the Precambrian-age crystalline basement complex and by rocks of Cretaceous to Tertiary age. The exploration for groundwater in this area requires a systematic technique in order to obtain optimum results, but the non-availability of funds and facilities has made it extremely difficult to carry out site investigations prior to the drilling of water wells. Therefore, the failure rate is as high as 80%. In order to delineate areas that are expected to be suitable for future groundwater development, black and white radar imagery and aerial photographs were used to define some hydrological and hydrogeological features in parts of the study area. Lineament and drainage patterns were analysed using length density and frequency. Lineament-length density ranges from 0.04–1.52; lineament frequency is 0.11–5.09; drainage-length density is 0.17–0.94, and the drainage frequency is 0.16–1.53. These range of values reflect the differences in the probability of groundwater potentials. Results were then used to delineate areas of high, medium, and low groundwater potential. Study results also indicate that correlations exist between lineament and drainage patterns, lithology, water temperature, water conductivity, well yield, transmissivity, longitudinal conductance, and the occurrence of groundwater. Received, August 1994 · Revised, March 1996, June 1996 · Accepted, October 1996     

遥感影像地表温度反演与地热资源预测——以石家庄地区为例

热红外遥感技术可以反演地表温度信息,可在地热资源预测方面发挥重要作用.研究基于京津冀地区地热成藏模式,利用单窗算法反演出石家庄地区2015年3月6日地表温度,结合夜间热红外影像、遥感构造解译结果和剩余重力异常数据,综合分析,相互论证,圈定1处山地对流型地热远景区和2处沉积盆地型地热远景区.其中,平山县寺沟村昼夜地温值均...     

Lithofacies paleogeography mapping and reservoir prediction in tight sandstone strata: A case study from central Sichuan Basin,China

Sand-rich tight sandstone reservoirs are potential areas for oil and gas exploration. However, the high ratio of sandstone thickness to that of the strata in the formation poses many challenges and uncertainties to traditional lithofacies paleogeography mapping. Therefore, the prediction of reservoir sweet spots has remained problematic in the field of petroleum exploration. This study provides new insight into resolving this problem, based on the analyses of depositional characteristics of a typical modern sand-rich formation in a shallow braided river delta of the central Sichuan Basin, China. The varieties of sand-rich strata in the braided river delta environment include primary braided channels, secondary distributary channels and the distribution of sediments is controlled by the successive superposed strata deposited in paleogeomorphic valleys. The primary distributary channels have stronger hydrodynamic forces with higher proportions of coarse sand deposits than the secondary distributary channels. Therefore, lithofacies paleogeography mapping is controlled by the geomorphology, valley locations, and the migration of channels. We reconstructed the paleogeomorphology and valley systems that existed prior to the deposition of the Xujiahe Formation. Following this, rock-electro identification model for coarse skeletal sand bodies was constructed based on coring data. The results suggest that skeletal sand bodies in primary distributary channels occur mainly in the valleys and low-lying areas, whereas secondary distributary channels and fine deposits generally occur in the highland areas. The thickness distribution of skeletal sand bodies and lithofacies paleogeography map indicate a positive correlation in primary distributary channels and reservoir thickness. A significant correlation exists between different sedimentary facies and petrophysical properties. In addition, the degree of reservoir development in different sedimentary facies indicates that the mapping method reliably predicts the distribution of sweet spots. The application and understanding of the mapping method provide a reference for exploring tight sandstone reservoirs on a regional basis.     

基于地球化学异常特征揭示地质构造——以四川惠远寺地区为例

为查明研究区地质构造活动特征,以四川道孚县惠远寺地区为研究对象,开展了1:5万区域地球化学扫面工作,将典型元素的异常分布和背景值特征与区内已知断裂构造、出露岩体、地质界线等进行对比研究.结果表明:元素(或异常)分布特征与断裂活动、岩体和地层分布相匹配,表现出受已知地质构造(鲜水河断裂带)的影响很大;地球化学异常的形成和迁移与成矿期的构造作用密切相关,相关资料可用于反演推断地质构造活动特征;在已知断裂的基础上,结合化探资料和地质观察,对地质体空间分布和构造界限的位置做出推测,初步厘定区内存在推测断层6条.该研究对未知地区和隐伏性地质构造提出推断,为后续找矿勘探提供依据.     

Geological structure revelation based on geochemical anomalies: A case study in Huiyuan Temple area of Sichuan Province

In order to probe the characters of tectonic structures in the study area, the authors conducted the 1:50 000 regional geochemical profile scan and took Huiyuan Temple area in Daofu County of Sichuan Province as a case study. The anomaly distribution and background value characters of the typical elements were compared with the known inferred faults, hidden rocks and geological boundaries. The results show that element (or anomaly) distribution characters correspond to the characters of fault activities, rocks and strata, which have been largely affected by the known geological structure (Xianshuihe Fault Zone). The formation and change of geochemical anomaly is closely related to those tectonic structures during the metallogenic period. Therefore, these data could be used to invert and infer the tectonic activity charaters. Based on the known faults and combined with the geochemical data and geological observation, the authors preliminarily inferred the spatial distribution of geological bodies and the locations of tectonic boundaries, and identified six inferred faults. This research aims to infer about those unknown regions and concealed geological structures, which provides some reference for future geological prospecting.     

从钻井测温曲线看地下水流方向及油气储藏条件——以川东南地区丁山1井为例

实测丁山1井测温曲线显示:温度向井底持续升高,井口温度25℃左右,井底温度107.5℃。温度曲线在1 000～3 000 m深度范围内出现"上凸"的扰动现象。现今平均地温梯度纵向上分段明显:三叠系及二叠系地层平均地温梯度为23.94℃/km;志留系和奥陶系地层平均地温梯度较大,为37.27℃/km;寒武系地层平均地温梯度较低,为16.65℃/100m。根据地温梯度分段性特征与地层热导率、地层岩性的相关性分析认为地下流体垂向上升运动造成了温度曲线扰动。进而推断出下奥陶统—中寒武统的地层具有较高的孔隙度和渗透率,而中奥陶统—志留系的地层则具有良好的封堵性,而这种上盖下储的地层组合,对油气成藏较为有利,反映了川东南地区下组合良好的油气储藏条件。     

基于地球化学异常特征揭示地质构造——以四川惠远寺地区为例

为查明研究区地质构造活动特征,以四川道孚县惠远寺地区为研究对象,开展了1:5万区域地球化学扫面工作,将典型元素的异常分布和背景值特征与区内已知断裂构造、出露岩体、地质界线等进行对比研究。结果表明: 元素(或异常)分布特征与断裂活动、岩体和地层分布相匹配,表现出受已知地质构造(鲜水河断裂带)的影响很大; 地球化学异常的形成和迁移与成矿期的构造作用密切相关,相关资料可用于反演推断地质构造活动特征; 在已知断裂的基础上,结合化探资料和地质观察,对地质体空间分布和构造界限的位置做出推测,初步厘定区内存在推测断层6条。该研究对未知地区和隐伏性地质构造提出推断,为后续找矿勘探提供依据。     

浙江泰顺龟湖叶腊石矿床热液蚀变短波红外光谱分析

蚀变岩帽与斑岩体关系密切,具有形成斑岩-浅成低温热液型矿床的潜力.位于浙闽交界的龟湖地区发育规模巨大的蚀变岩帽(>30 km2),形成了龟湖超大型叶腊石矿床,矿体属于岩帽的一个分带.矿床及其围岩蚀变主要由粒度微小或隐晶质的层状硅酸盐蚀变矿物组成,矿物之间差别极为细微,仅凭肉眼难以区分.短波红外光谱技术可以有效识别这些蚀...     

基于宽频大地电磁法的页岩气探测实践——以川西南沐川地区须家河组为例

四川盆地上三叠统须家河组陆相富有机质页岩较为发育,页岩连续厚度较大,含气性好,有望开辟四川盆地页岩气新区新层系。然而,复杂的人文干扰（城镇密集、人口众多）和较大的埋藏深度（2000~3000m）挑战了页岩气地球物理勘探的精度,这在很大程度上制约了川西南沐川地区三叠系须家河组页岩气的进一步勘探。本文在分析前人研究资料基础上,优选了川西南沐川地区须家河组作为新区新层系的探测目标,根据研究区地质情况,构建理论电性模型,通过正演模拟和“已知”钻孔标定方法试验,确定了宽频大地电磁法的适用性和有效性。进而在重点页岩气远景区部署一条宽频大地电磁剖面,通过数据处理分析,结合地质资料获得了研究区深部电性结构,认为研究区一带地层连续、完整,断裂不发育,具有稳定的地质结构,其中上三叠统须家河组发育较大厚度的富有机质页岩,可作为本区页岩气勘探的新区新层系,具有良好的页岩气、致密气资源前景。同时,证实了在3000m以浅页岩气探测方法中,宽频大地电磁法（BMT）可以有效地识别富有机质页岩规模和空间展布特征,是一种快速、经济、无损有效的页岩气探测方法,可以为页岩气勘探提供先导依据,同时也为同类地质情况页岩气探测提供应用示范。     

Irrigated area determination: a case study in the Province of San Juan,Argentina

Much of the central-western region of Argentina, where San Juan Province is located, experiences arid to semi-arid climatic conditions with low average annual rainfall accompanied by substantial evapotranspiration. Consequently, a viable crop industry depends to a large extent upon irrigation from major river systems. Increasing demand for water in the lower basin of the San Juan River is emphasizing the need for more accurate estimates of water used for irrigation. Since the water demand for a particular crop is very closely related to crop area, monitoring the area of crop under irrigation is considered a proxy for the amount of water used. Landsat 5 imagery for the growing season, field data and aerial photographs were used to evaluate crop area.     

Coupling near-surface geomorphology with mangrove community diversity at the estuarine scale: A case study at Dongzhaigang Bay,China

Coastal wetlands are key features of the Earth's surface and are characterized by a diverse array of coupled geomorphological and biological processes. However, the links between the distribution of biodiversity (for example, species and structural diversity) and the formation of coastal geomorphology are not well-understood on a landscape scale most useful to coastal zone managers. This study describes the relationship between select geomorphological and biological mangrove community features (i.e. species composition and functional root type) in a landscape-distributed coastal zone of Dongzhaigang Bay, north-eastern Hainan Island, China. A total of 11 mangrove species and five functional aerial root types were encountered, with the location of species by root types being controlled by the elevation of the soil surface. Plank roots, prop roots and pneumatophores occupied the lowest intertidal elevations, while knee roots and fibrous roots of the mangrove fern, Acrostichum aureum, preferred the highest intertidal elevations. Surface sediment deposition in areas with mangroves was greater than deposition in non-mangrove forest zones, establishing an important biological mechanism for this large-area response because surface erosion/compaction was also more prominent within mangrove roots. Indeed, functional root type influenced the magnitude of deposition, erosion and compaction, with knee roots and pneumatophores being more effective in promoting deposition and preventing surface erosion/compaction than prop roots. These results indicate a potential role for vegetation type (especially functional root type) to influence coastal geomorphological processes at large landscape scales. While soil surface elevation is correlated to the distribution of mangrove species and functional root types, a significant feedback exists between elevation change and the capacity of those root types to influence coastal geomorphological differentiation within sustainable intertidal elevations. An enhanced understanding of geomorphological development, mangrove species distribution and functional root type may improve management to support nature-based solutions that adjust more effectively to sea-level rise through feedbacks.     

Study on the oasis landscape fragmentation in northwestern China by using remote sensing data and GIS: a case study of Jinta oasis

The purpose of this study is to investigate the oasis landscape fragmentation in northwestern China’s arid regions. Landscape maps of Jinta oasis were compiled by using GIS based on Landsat TM data of 1990 and 2000. Landscape indexes for evaluating fragmentation are patch area, patch density, corridor density and split index. Results indicated many difference. First, between the years 1990 and 2000, the landscape fragmentation in Jinta oasis decreased slightly. Second, the area of the matrix decreased at the class level. The landscape fragmentation of the matrix (bare soil) increased as a result of increased influence of human activities on matrix and was opposite to the irrigated farmland whose area is larger and more aggregated in 2000 than in 1990. Third, dense corridor system is one of the most prominent characteristics of the arid regions. It is one of the key factors resulting in the landscape fragmentation; especially the fragmentation within the same patch types. The corridor density of irrigated farmland, residential area and forestland were quite large in Jinta oasis both in 1990 and 2000. The pattern of Jinta oasis is characterized by agricultural oasis embedded in Gobi and in the desert, where the ecosystem was disturbed strongly by the intense human activities.