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181.
合理厘定西南天山构造属性,不仅对天山大地构造单元的准确划分具有重要科学意义,而且对中亚造山带的古生代构造演化也至关重要。通过对西南天山乌什北山地区的地质填图和构造解析,识别出5期构造变形,包括2期逆冲推覆构造。对主期逆冲推覆构造进行几何学、运动学研究表明,该逆冲推覆构造在空间上具有由北向南逆冲的运动学指向,并由北向南表现出由逆冲推覆构造的根带向前锋带变化的构造样式。根据逆冲推覆构造的物质组成及变形样式,认为西南天山乌什北山一带应属于塔里木板块北缘逆冲推覆构造带,从而为区域构造单元划分及西南天山晚古生代以来的构造演化过程提供构造变形方面的依据。 相似文献
182.
杨志华 《地球科学与环境学报》1996,(1)
地层是多重的,岩石地层及其单位是多种的。文中对多种岩石地层的概念、单位命名方案提出了意见,并对它在实际中的应用作了初步的尝试。 相似文献
183.
The volcanosedimentary units of Late Mesozoic-Tertiary age that outcrop in the Southeast Anatolian orogenic belt are commonly
referred to as the Maden complex. There is a long-lasting controversy over its definition, age, stratigraphic and structural
position, and the origin, and thus, the orogenic evolution. To solve this problem, large strips across the Southeast Anatolian
orogenic belt have been studied extensively, and different rock groups which were regarded previously as the Maden unit have
been differentiated. Their major characteristics and differences have been identified. The Maden unit sensu stricto is here
redefined as a volcanosedimentary succession of Middle Eocene age representing a short-lived back-arc basin which reached
the stage of an embryonic ocean. Presently, the Maden group occurs mainly within the lower nappe stack of the nappe zone of
the Southeast Anatolian orogen. It rests stratigraphically on an amalgamated nappe package consisting of the different metamorphic
tectonic units and, in turn, is overlain tectonically by the upper nappe units. 相似文献
184.
发展多种经营企业,是社会主义市场经济的需要,是地勘单位体制改革的必然趋势,产权单一,事企不分,人才匮乏、技术滞后,观念陈旧,市场不畅,是影响部分地勘单位多种经营企业发展的主要因素,只有在体制、科技和市场开拓等方面进行改革创新,才是地勘单位多种经营企业自我生存,自我发展的正确道路。 相似文献
185.
GIS支持下的不规则单元划分及地质信息提取 总被引:2,自引:0,他引:2
在矿产资源定量预测中,单元是预测模型与地质信息联系的桥梁,是统计分析的基础。传统的规则网格单元划分方法虽然给矿产预测的计算机化带来了方便,但也存在许多问题。作者在本文中初步论述了在地理信息系统的支持下不规则地质体单元的划分方法,以及利用GIS的空间数据分析功能提取出不规则单元中的地质信息。 相似文献
186.
Three-dimensional geologic modeling and visualization of the Virttaankangas aquifer,southwestern Finland 总被引:1,自引:1,他引:1
Aki Artimo Joni Mäkinen Richard C. Berg Curtis C. Abert Veli-Pekka Salonen 《Hydrogeology Journal》2003,11(3):378-386
A need exists for a reliable and long-term water supply for the 285,000 inhabitants of the Turku area in southwestern Finland.
In response to this need, there are plans to replace the present water supply from the surface sources with artificially infiltrated
groundwater from a Quaternary esker aquifer called the Virttaankangas aquifer. New sedimentological studies of the Virttaankangas
area have revealed the complexities of the esker system and its surrounding glacial, glaciofluvial, and glaciolacustrine geology.
This led to the characterization of the hydrogeological units of the aquifer, the result of which has been a three-dimensional
(3-D) truly integrated solids model that represents the geometry, interrelationships, and hydrostratigraphy of the study area.
The 3-D model was made with EarthVision geologic modeling software. The 3-D geological model of the Virttaankangas aquifer
can be used for planning the infiltration of river water into the aquifer and to understand the geologic and geographic boundaries
of the hydrogeologic units hosting the groundwater reserve and the geologic relationships between the units. Another major
outcome of this study is a powerful visualization tool that will be provided to municipal and government authorities who must
understand the geologic complexities involved with water-resource planning prior to their decision making.
Electronic Publication 相似文献
187.
Introduction At the juncture of Qinghai-Xizang, Ordos and Alxa blocks lies the Qinghai-Xizang plateau, an area with complicated topographic and morphologic features, strong tectonic activities and frequent earthquakes (many large-magnitude earthquakes have taken place), has become a focal area for geoscience study. Many geophysical and geological surveys have been carried out in and around the area, such as deep seismic sounding (DSS), gravimetry, magnetotelluric sounding, magnetic anomaly … 相似文献
188.
Exposures in a now-infilled pit mined for platiniferous UG2 chromitite in the Bushveld Complex, South Africa, are described. The layer of chromitite is underlain by anorthosite, providing a dramatic colour contrast. The interface between these two rock types shows evidence of various scales of irregularities. In plan view, small circular depressions, less than 3 cm across and 5 mm deep, occupy about 20% of the surface. Between them, the contact is planar. The anorthosite, immediately underlying the chromitite, has a planar fabric visible in thin sections that is not disturbed beneath these small depressions. Another set of depressions occurs, about 40 cm in diameter and with variable depth (< 40 cm). Again they are approximately circular. Larger structures, called potholes, reach several metres. No regular distribution pattern is apparent in any of these structures.
Several possible processes are reviewed for the origin of these irregularities, especially the small-scale structures, but none explains all the features noted. These processes include remelting, diapirism, impact-generated dimpling, gas escape, and interference rippling. We present a photographic record of these structures, but present no definitive model for their interpretation. 相似文献
189.
190.
从分析阻碍地勘单位企业化进程中存在的体制、资源、职工信心和矿业权归属等主要难点问题入手,提出了继续争取国家政策扶持、事企彻底分离、加大产权制度的改革力度、加快企业重组、加快人事制度改革、以及依托大集团优势达到壮大企业经济规模的相应对策. 相似文献