Chahkuh Gorge

Chahkuh Gerge is located in the northwest of Qeshm Island, near the Chahu Sahrghi village. This geosite represents a significant and unique example of running water erosion and forming a canyon valley. The rapid and powerful water current in torrential and uncommon rains has been the main factor in shaping this gorge. However, water erosion is the second factor to form this gorge and has occurred along a joint and the main fracture. The floors surrounding this gorge are part of the Salakh anticline ridge where the Salt Dome is exposed. Anticline is a type of dome-like fold with a convex-up structure that is formed by internal and lateral earth pressures. Because of lateral pressures and elongation of the anticline layers, joints, fractures, and faults appear at the edge of the anticline. The joints and fractures in Chahkuh Gorge are the weaknesses of the edge, and erosive factors in these points have stronger and more effective performance. The Chahkuh Gorge is one of these primitive fractures that developed gradually by erosive factors. In the vertical direction of the main gorge, another gorge includes a very prominent linear crevice that can be observed along the fracture. One feature of the geological formation of Chahkuh Gorge is water impermeability. This feature leads to water flowing through and fills the fissures and cracks and gradually causes them to be eroded. Generally, the anticlines and their surrounding areas are considered turbulent and unstable regions, which causes the formation of faults and cracks. Due to the mechanical function of water, non-uniform substances, as well as erosion, linear, elliptical, and spherical concave shapes, have been created in the walls of the gorge. Also, due to the movement and rotation of rock fragments by water flow inside the gorge, ditches, bowl-like shapes, potholes, and other erosive forms have been created. The locals have utilized this feature by digging holes in the bottom of the gorge to collect and store rainwater. Due to the drought and the significant value of rainwater in the past, this invention has been highly valuable and effective. Tectonic structures: One of the visible phenomena in the Chahkuh gorge is the function of east-west faults, which are formed perpendicular to the main valley. These faults, which are parallel to each other, have an almost vertical fault mirror with left-slip surfaces and a normal component. The pigeonhole erosion (Tafoni) is a form of dissolution erosion in sandstone layers. In this type of erosion, winds containing saltwater droplets, after evaporation and crystallization of salt crystals, cause the sandstone to be separated into sheets and grains. In this picture, the flat surfaces of the ridges and arches indicate that these surfaces are equally affected by other erosion processes such as rapid water and wind erosions.