摘要
对大别山高压-超高压变质岩剥露地表的时间以及前陆盆地对郯庐断裂带起源的指示等重要问题进行了探讨。前陆盆地上三叠统至下一中侏罗统砂岩的端元组分分析结果指示了前陆盆地的物源区为大别造山带。砂岩成熟度从近断裂带处的1．54左右变化为远离断裂带处的5．4左右，反映了前陆沉积盆地中黄马青群及象山群应是直接来自大别造山带的原地沉积，也说明郯庐断裂带在晚三叠世时可能已经存在于大别山东缘。伊利石的结晶度多数介于0．24°～0．39°（△2θ），多型为2M型和1M＋2M1型，指示了当时前陆沉积的热演化温度为190-320℃，从而反映了前陆沉积的最大原始埋深约为10000m。
This paper deals with the time that high pressure （HP） to ultrahigh-pressure （UHP） metamorphic rocks exhumed to the surface and the relation between the deposits in the foreland basin and the origin of the Tan-Lu fault zone. The point-counting analysis of sandstones from Huangmaqing and Xiangshan Groups shows that the provenance of the foreland basin is Dabie Mountains. The maturity index is lower in the area near the Tan-Lu fault zone （about 1.54 p. f. u） and higher in the area far from the fault zone （about 5.4 p. f. u, at most 7. 2 p. f. u）, which indicates that the sediments in the foreland basin are direct deposits from Dabie Mountains and that the Tan-Lu fault zone may occur on the eastern margin of Dabie Mountains in later Triassic. It is found from analysis of polytype and crystallinity of illite that the temperature of the foreland basin is 190-320 ℃, which shows that the maximum primary depth of sediments in the foreland basin is about 10 000 m.
出处
《合肥工业大学学报（自然科学版）》
CAS
CSCD
北大核心
2006年第4期448-453,共6页
Journal of Hefei University of Technology：Natural Science
