ARTYKUŁY INFORMACYJNE Procesy geomorfologiczne na wybranych wysadach soli w pasie fałdowo-nasuwczym gór Zagros w Iranie
Abstract
Geomorphological processes in selected salt domes in the Zagros fold-thrust belt in Iran.
A b s t r a c t. Presently, about 160 salt domes of various sizes exist in the Zagros fold-thrust belt in southern Iran. The salt domes constitute a unique proving ground for research on salt tectonics. In the dry climate that currently dominates in Iran, forms of horizontal salt formations are created, referred to as salt glaciers, in addition to typical steeply falling salt domes. Consequently, it is possible to conduct observations of geomorphological processes developing on the surface of exposed salt rocks and keep a continuous record of their tectonic activity. Salts occurring in that area represent the Hormuz (Hormoz) Formation of the Ediacaran period (Late Neoproterozoic to Early Cambrian). The rocks of the formation usually present a colourful blend of rock salt, anhydrite, black dolomite, shale, and red volcanic tuff, as well as extrusive magmatic and metamorphosed rocks that are interpreted as fragments of deep basement elevated to the land surface by salt domes. The paper describes the geology and geomorphology of the Jashak (Dashti) salt glacier from the Busher Province and two salt domes located on the Persian Gulf Islands: Hormuz (Hormoz Island) and Namakdan (Qeshm Island). The present- day salt dome geomorphology is a result of both climatic effects (precipitation and air temperature) and diapir uplifting forces.
A b s t r a c t. Presently, about 160 salt domes of various sizes exist in the Zagros fold-thrust belt in southern Iran. The salt domes constitute a unique proving ground for research on salt tectonics. In the dry climate that currently dominates in Iran, forms of horizontal salt formations are created, referred to as salt glaciers, in addition to typical steeply falling salt domes. Consequently, it is possible to conduct observations of geomorphological processes developing on the surface of exposed salt rocks and keep a continuous record of their tectonic activity. Salts occurring in that area represent the Hormuz (Hormoz) Formation of the Ediacaran period (Late Neoproterozoic to Early Cambrian). The rocks of the formation usually present a colourful blend of rock salt, anhydrite, black dolomite, shale, and red volcanic tuff, as well as extrusive magmatic and metamorphosed rocks that are interpreted as fragments of deep basement elevated to the land surface by salt domes. The paper describes the geology and geomorphology of the Jashak (Dashti) salt glacier from the Busher Province and two salt domes located on the Persian Gulf Islands: Hormuz (Hormoz Island) and Namakdan (Qeshm Island). The present- day salt dome geomorphology is a result of both climatic effects (precipitation and air temperature) and diapir uplifting forces.