云贵川鸡鸣三省大峡谷景观特征及形成机理研究

On Landscape Characteristic and Formation Mechanism of Yunguichuan Big Valley

云贵川鸡鸣三省大峡谷地质遗迹景观,平面形态以喇叭状和常态为主,截面形态类型多样,主要有对称和不对称的"U"形、"V"形、"√"形、箱形或地缝式等形态,在纵向上以层层叠叠的断崖为景观特色.根据峡谷景观特征及分布,结合区内地层岩性展布、地质构造及水文地貌特征,分析云贵川鸡鸣三省大峡谷的形成机理.结果表明,鸡鸣三省大峡谷的景观形态与区内地层岩性展布、峡谷发育所处的构造部位和断层节理的发育有密切联系.根据研究分析区内两种形态的峡谷形成因素及各因素的耦合关系,提出了云贵川鸡鸣三省大峡谷主要经历溶蚀期、崩塌期(侵蚀期)和搬运期3个时期,并在地层岩性展布、地质构造、岩溶水文地貌因素等影响下,形成喇叭状和常态两种峡谷类型的演化模式.

Geological relic landscape of Jiming Grand Canyon in Yunnan,Guizhou and Sichuan has trumpet and normal plane shapes.The cross section shapes include symmetrical and asymmetrical“U”shape,“V”shape,“√”shape,box shape or ground crack and other shapes.Folds of bluff are longitudinal landscape features.In the paper,formation lithologic distribution,geological structure and hydrological features in the zone have been combined for analyzing the generation mechanism of Jiming Grand Canyon in Yunnan,Guizhou and Sichuan according to characteristics and distribution of the canyon landscape.It is believed that the landscape form is tightly related to formation lithologic distribution,structural location of canyon development part and development of fault joint in Geological relic landscape of Jiming Grand Canyon in Yunnan,Guizhou and Sichuan.The coupling relationship between canyon generation factors and other factors of two forms in the zone have been studied and analyzed.It is proposed that Jiming Grand Canyon in Yunnan,Guizhou and Sichuan mainly experienced three stages of erosion period,collapse period and(erosion period)moving period,etc.The evolution models of trumpet and normal plane shapes are formed under the influence of strata lithology distribution,geological structure,karst hydrological landscape factors,etc.