滇西南昌宁-孟连带南皮河群地层、沉积特征及其构造古地理意义

南皮河群位于滇西南昌宁－孟连带西区，其地层序列已受到后期构造作用改造，总体呈无序状态，但其内部的各岩片地层仍保持相对连续的地层层序、据此，我们将南皮河群划分为下、中、上段，对其中各段的沉积特征和构造背景作了详细研究。甫皮河群下段为一套浊流、滑塌浊流、碎屑流和等深流沉积类型；中、上段为深水洋盆边缘沉积类型、其沉积构造背景为被动大陆边缘呈拉张状态的深水陆坡－洋盆边缘环境，物源区为西侧的保山－耿马地块。

STRATIGRAPHY,SEDIMENTOLOGY AND TECTONIC PALAEOGEOGRAPHY OF THE NANPIHE GROUP IN THE CHANGNING-MENGLIAN ZONE,SOUTHWESTERN YUNNAN

The Nanpihe Group is located in the western part of the Changning-Menglian zone insouthwestern Yunnan. Although its stratigraphic successions have been reworked chaoti-cally by tectonism, there exist a lot of stratal slices with relatively continuous sequences.The sedimentary characteristics and tectonic settings enable the distinction of three members: upper,middle and lower members. The lower member of the Nanpihe Group is made up of a series of turbidites, fluxoturbidites, debris flow deposits and contourites. The.middle and upper members of the group consist of the deposits on the margins of the deepwater oceanic basin. The tectonic settings of the group represent the deep-water extensional continental slope to oceanic basin margin environments on the passive continental margin. The principal source of detritus lay to the western Baoshan-Gengma block.