Subjects: Geosciences >> Geography submitted time 2024-05-20 Cooperative journals: 《干旱区地理》
Abstract：由于造景岩石普遍为钙质和铁质胶结的砂岩和砾岩，丹霞地貌具有独特的景观特征和成因机制，同时因具有较高的科学和观赏价值而成为备受关注的旅游资源。东南湿润区丹霞地貌的研究程度较高，但是对西北干旱气候区丹霞地貌的研究还比较少见。以新疆阿克苏温宿大峡谷为研究对象，通过野外调查、样品显微镜观察、盐化学和元素地球化学实验以及ArcGIS面积高程积分（Hypsometric integral，HI）方法，探讨该地区丹霞地貌的特征和成因。结果显示：（1）研究区呈现峡谷、山峰及峰林景观，以发育陡崖泥流林和顶盖型石柱为特色，其造景岩石主要为新近纪河流相红色砾岩和砂岩，硬度较高的砾岩层为形成顶盖型石柱提供了有利保障。（2）红层位于温宿盐丘附近，岩石含盐量较高，主要的盐类型为氯化物、硫酸盐和硝酸盐。陡崖洞穴风化碎屑物样品中的大部分主量元素相对于表岩迁出，说明干旱气候下化学风化仍较活跃。（3）面积高程积分显示研究区南部HI值为0.61，处于幼年期，而北部HI值为0.38，处于老年期，整体地貌演化发育阶段差别较大。研究区虽然降水量较低，但河流侵蚀作用明显，同时构造也是影响丹霞地貌演化的主要因素。
Subjects: Geosciences >> Geology submitted time 2023-05-17 Cooperative journals: 《干旱区地理》
Abstract： There are more than 54 spots of Danxia landforms in Shaanxi Province, northwest China, which are distributed in the Weibei Uplift and Yishan Slope of the Ordos Basin. In terms of landscape, both positive and negative Danxia landforms have considerable regional differentiation from southwest to northeast of the province. The sandstones of aeolian desert facies with mainly near horizontal or gently inclined Danxia occurrences are the most widely distributed. They are characterized by gully Danxia, wave Danxia, and colored hills, and most of them are in their early stage. The spatial structure type of Danxia landform distribution in Shaanxi Province is condensed, with two high-density areas (Ganquan-Zhidan-Ansai-Fuxian Danxia area and Yulin Jingbian Danxia area), one medium-density area (Zhaojin-Xunyi-Binxian Danxia area), and two low-density areas (Baoji Jiulongshan area and Fugu Lianhuachan area) according to the nearest neighbor index and nuclear density analysis methods. From the viewpoint of the formation mechanism, Mesozoic sedimentation in the Ordos Basin laid the material foundation for the Danxia landform, regional tectonic evolution controls the distribution of positive and negative landforms, and characteristics of joints and fissures are critical in the landscape pattern of the Danxia landform, and water and wind erosions are the leading forces shaping the landscape form of the Danxia landform.
Subjects: Geosciences >> Geology submitted time 2021-04-13 Cooperative journals: 《干旱区地理》
Abstract： 延安地区丹霞地貌是国内外地貌学界近年来的最新发现和持续关注点。通过对延安地区 丹霞地貌地质遗迹的系统调查和研究发现，该区丹霞地貌景观资源丰富，类型多样，具有较高的观 赏价值和科学研究价值。通过野外考察和岩石样品分析，从地质构造、地层组合、岩性特征和外动 力等方面来探讨延安地区丹霞地貌的发育机制。研究表明：晚白垩世以来，该地区经历多次构造 抬升和新生代以来地壳保持差异升降，区内构造简单，地层产状平缓，但节理、裂隙数量较多，对延 安地区丹霞地貌的发育具有控制作用；延安地区丹霞地貌造景岩层主要为白垩系志丹群洛河组（K1l），为一套干旱气候条件下的红色碎屑岩沉积，沉积环境为沙漠环境，岩层倾角近于水平，为丹 霞地貌的发育提供了较好的物质基础；岩性特征上，延安地区丹霞地貌造景岩层岩石成熟度不高，硬度低易碎，抗侵蚀能力较弱，岩石具有相似的矿物组成及峰值强度分布，其沉积过程经历了较为 复杂的风力作用过程，岩石强度存在差异性，易受到后期外动力作用的改造；外动力方面，季节性 的流水是塑造“沟谷型”丹霞地貌的主要外动力，此外，凹片状和凸片状风化作用以及崩塌作用对 延安丹霞地貌的发育也有重要影响。
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