Les manifestations tectono-sédimentaires d'âge Campanien–Maastrichtien en Tunisie : implications sur l'évolution géodynamique de la marge Nord-AfricaineThe Campanian–Maastrichtian synsedimentary tectonic activity: implication in the geodynamic evolution of the North African Margin

The synsedimentary tectonic activity evidenced in central and northern Tunisia points out the fact that the Campanian–Maastrichtian deposits are associated with several NW–SE and east–west normal faults. These results suggest that the east–west transform fault of North African Margin is still active during this stage. These data allow us to discuss a new geodynamic model for the North African Margin. To cite this article: M. Dlala, C. R. Geoscience 334 (2002) 135–140.     

中国铝土矿成矿作用的物质来源与深时环境因素：进展与讨论

铝土矿是工业上可供利用的铝矿石总称,可视为陆表化学风化作用的终极产物。作为一种战略性大宗矿产,当前我国铝土矿使用总量的60%以上依赖于进口铝土矿石,铝土矿及其伴生的其他金属资源对国家资源安全的重要性突出。铝土矿化作用、红土化作用、热带成壤作用是热带风化作用的不同表现形式,主控因素包括适宜的气候(温度、降水)、侵蚀速率、母岩、时间、植被、地形地貌等。三者之间存在联系,但区别也较为显著,主要体现在时间尺度和沉积作用复杂程度两方面。红土化作用或热带成壤作用可能包含在铝土矿化作用的某一阶段。中国铝土矿资源主要集中在晚古生代,在不同地区存在不同的物质来源,可概括为：稳定的板块内部原地-准原地物源、板块边缘异地火山活动物源、板块边缘造山带异地物源3种主要类型。物源成分则可能来自于下伏沉积岩基底或板块边缘火山弧物质,或者两者的混合供给。不同成矿物质来源的铝土矿中保存了特征明显的碎屑锆石年代学分布规律,且在一定程度上决定了不同地区铝土矿床的地球化学组成特征,其中TiO₂含量变化显著,可视为潜在的物源指标。中国晚古生代铝土矿化作用除特殊的大地构造背景外,古气候、海平面变化、古水文条...     

Mesozoic–Cenozoic multistage tectonic evolution of the Pamir: Detrital fission-track constraints from the Tajik Basin

Knowledge of the tectonic history of the Pamir contributes to our understanding of both the evolution of collisional orogenic belts as well as factors controlling Central Asian aridification. It is, however, not easy to decipher the Mesozoic–Cenozoic tectonics of the Pamir due to extensive Neogene deformation in an orogen that remains largely understudied. This study reports detrital apatite and zircon fission-track (FT) ages from both the eastern Tajik Basin sedimentary rocks and Pamir modern river sands. These FT data, supported by vitrinite reflectance and zircon and apatite U–Pb double dating, suggest that the majority of the FT ages are unreset and record exhumation stages of the Pamir, which has served as the source terrane of the Tajik Basin since the Cretaceous. Furthermore, we combine the new data with a compilation of published detrital apatite and zircon FT data from both the Tajik Basin sedimentary rocks and Pamir modern river sands, to explore the Mesozoic–Cenozoic tectonic history of Pamir. Deconvolved FT Peak Ages document two major Mesozoic exhumation events associated with the Late Triassic–Early Jurassic Cimmerian orogeny that reflects accretion of the Pamir terranes, as well as the Early–early Late Cretaceous deformation associated with the northward subduction of the Neo-Tethys Ocean beneath Pamir. The compiled data also show significant Late Eocene–Neogene exhumation associated with the ongoing formation of the Pamir, which peaks at ca. 36, 25, 14 and 7 Ma.     

从第32届国际地质大会看矿床学及相关学科的进展

第32届国际地质大会中有关矿产方面的动态和进展主要分为以下4个部分：与黑色页岩有关的矿床;中亚地区的矿床及构造;锡、钨及其他稀有金属矿床的新发展;海洋矿床的最新发展。