剑门关丹霞地貌晚侏罗—早白垩系沉积相的马尔科夫链特征

Markov chain characteristics of Late Jurassic-Early Cretaceous sedimentary facies of the Danxia landform in Jianmenguan Pass

丹霞地貌是我国五大地貌之一,具有极大的科研和观赏价值。剑门关丹霞地貌具有年代新、类型多、分布较集中等特点,主要形成于侏罗—白垩纪,沉积岩层自下而上包括上侏罗统的遂宁组、莲花口组和下白垩统的剑门关组。根据沉积序列与旋回研究,将剑门关丹霞地貌沉积相划分为山麓-洪积扇、河流、湖泊、三角洲沉积相,运用马尔科夫链法建立丹霞地貌的沉积相序,形成沉积相模式,对研究剑门关丹霞地貌的古地理和古环境具有重要意义。

The Danxia landform is one of China＇s five landforms, boasting great scientific and artistic value. The Danxia landform in Jianmenguan Pass is featured with new age, various types and centralized distribution. Formed during Jurassic-Cretaceous period, its sedimentary strata can be divided （in ascending order） into Upper Jurassic Suining Formation, Upper Jurassic Lianhuakou Formation, Lower Cretaceous Jianmenguan Formation. In respect of sedimentary sequence and cycle, the Danxia landform of Jianmenguan Pass is piedmont-diluvial fan, fluvial deposit, lacustrine deposit, delta deposit. Markov chain method is used to establish the sedimentary sequence of the Danxia landform and its sedimentary facies modes, which is of great importance in studying the palegeography and paleoenvironment of the Danxia landform in Jianmenguan Pass.