Bailiya Basin is located in west-north segment of Xianshuihe active fault zone,east Tibet Plateau. Working in the field and utilizing Google Earth map, this paper describes a series of structural landform; trough on slope, offset streams, offset of terrace, triangular facet,deformed terrace surface , abandoned river,rift lake. T4 is cut off by Luhe active fau Kerilong river goes through T3 (14. 92kaB. P. ) ,and approximately flows along Luohe active fault. This probably means that the tectonic stress field has been changed, Bailiya Basin is formed.rnAges by OSL dating ( T1, T2 , T3 and T4 ) are followed:1. 06± 0. 06kaB. P., 1. 83± 0. 06kaB. P., 14. 92± 0. 76kaB. P. And 42. 48±2. 35kaB. P., these times perhaps are when the terraces were formed. Since 42. 48 and 14. 92kaB. P.,the Luhe active fault sinistral strike-slip velocities decreased from 3. 73mm/a(42. 48kaB. P. -now) to 0. 85mm/a( 14. 92kaB. P. ~ now) ; The rates perhaps show that the fault level slip velocities decreased from Late Pleistocene( Q3: 42. 48ka) to now. The Daqu( River) incision rates increased from T4 ~ T3 (42. 48 - 14. 92kaB. P., 0. 14mm/a)to T3 ~T2(14. 92 ~1. 83kaB. P. ,4. 66mm/a) and T2 ~ Tl ( 1. 83 ~ 1. 06kaB. P.,5. 19mm/a) ; These illustrate that terrace incision rates speed up from Late Pleistocene( Q3:42. 48ka)to now.%白利雅盆地位于青藏高原东部,鲜水河断裂带北西段炉霍活断层与达曲活断层的斜接部位.通过野外实际考查,结合Google Earth地图发现白利雅盆地发育一系列的构造地貌:断层三角面、坡中槽、断错阶地、废弃河道、裂陷湖和阶地面变形.盆地发育的4级阶地是构造成因.废弃河道是新的断裂活动形成的新冲沟、新河道——达曲,其快速下切,废弃老河道,形成狭长的‘U’型沟谷.鲜水河断裂的北西段炉霍活断层切过T3河流阶地,说明其(白利雅以北)是在大约14.92kaB.P.以后形成的,可能预示着构造应力场的变化和白利雅盆地形成.对盆地4级阶地(T1,T2,T3和T4)的河流沉积物光释光(OSL)测年结果分别是1.06±0.06kaB.P.,1.83±0.06kaB.P.,14.92±0.76kaB.P.和42.48±2.35kaB.P,代表了相应阶地的沉积年龄.这些结果与阶地前缘陡坎断错的距离计算显示,从42.48kaB.P.和14.92kaB.P.以来,断层走向平均移动速率分别为3.73mm/a和0.85mm/a,显示从中更新世晚期以来,鲜水河断裂带炉霍活断层水平滑移有减慢的趋势.在42.48 ～ 14.92kaB.P.,14.92～1.83kaB.P.和1.83 ～ 1.06kaB.P.,相邻阶地垂向隆升或河流下切的速率分别为0.14mm/a(T4～T3),4.66mm/a(T3 ～ T2)和5.19mm/a(T2～ T1),显示从中更新世晚期以来,阶地垂直隆升或河流下切有加快的趋势.
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