晋冀蒙交界东六马坊幅1:50000地质图数据库

1:50000 Geological Map Database of the Dongliumafang Map-sheet at the Junction of Shanxi, Hebei and Inner Mongolia

东六马坊幅(K50E023002)位于晋冀蒙交界地区的恒山-桑干高压麻粒岩带内,属华北克拉通典型的早前寒武纪高级变质岩区。东六马坊幅1:50000地质图数据库按照中国地质调查局新颁布的《区域地质调查技术要求(1:50000)》(DD 2019-01)和行业其他统一标准及要求,采用现代变质岩区填图技术方法和数字填图采集系统编制完成。该图幅对区内新太古代-新生代地层、岩浆岩、变质作用以及构造等进行了详细的划分厘定:建立了新太古代桑干岩群和古元古代集宁岩群4个构造–岩石地层单位以及中元古代-新生代13个地层单位;建立了新太古代-古元古代和中元古代-中生代(变质)侵入岩演化序列;识别出早前寒武纪3期变形构造样式和中-新生代印支期、燕山期和喜马拉雅期断裂构造形迹;识别出2类不同原岩性质的高压基性麻粒岩,并对变质作用期次进行了划分。图幅采用特殊线段及花纹表达了古老造山带深部地壳岩石塑性流变特征及构造变形样式,重塑了古元古代造山构造演化过程。该数据库为Map GIS格式,数据内容主要由1:50000地质图库、图饰部分及角图等组成,并包含9个锆石U–Pb年龄数据,数据量为53.8 MB。东六马坊幅1:50000地质图创新了高级变质岩区填图和图面表达方法,为高级变质岩区填图工作提供了参考范例。

The Dongliumafang Map-sheet(K50E023002)is located in the Hengshan-Sanggan high-pressure granulite belt at the junction of Shanxi,Hebei and Inner Mongolia.The 1:50000 Geological Map Spatial Database of Dongliumafang Map-sheet was compiled in accordance with the Technical Requirement for Regional Geological Survey(1:50000)(DD2019-01)newly issued by China Geological Survey and other relevant uniform standards and requirements,by using modern mapping technology for metamorphic rock area and digital mapping acquisition system.The map-sheet gave a detailed definition of the strata,magmatic rocks,metamorphism and tectonic structure in the Neoarchean-Cenozoic era in the area:four tectonic-lithostratigraphic units of the Neoarchean Sanggan Group and the Paleoproterozoic Jining Group,and 13 Mesoproterozoic-Cenozoic stratigraphic units have been established;the evolutionary series of Neoarchean-Paleoproterozoic and Mesoproterozoic-Mesozoic(metamorphic)intrusive rocks have been established;the structural deformation style of three periods of Early Precambrian,and the fracture structure in the Mesozoic-Cenozoic Indosinian,Yanshanian and Himalayan periods have been identified;two types of high-pressure basic granulites with different protolith properties have been identified,with metamorphic periods divided.The map-sheet uses special line segments and patterns to express the plastic rheological characteristics and structural deformation style of deep crustal rocks in the ancient orogenic belt,and has reconstructed the evolution process of Paleoproterozoic orogenic tectonics.The database adopts a Map GIS format and comprises 1:50000 geological map library,map appearance and corner maps,and contains nine data pieces of zircon U-Pb age,with a data volume of 53.8 MB.The 1:50000 Geological Map of Dongliumafang Map-sheet has innovated the mapping techniques for high-grade metamorphic areas as well as map expression methods,setting an example for mapping work on high-grade metamorphic rock areas.