Refference : The 25th Symposium on Geoscience;Tehran
Publishing Year : 1385

Abstract :

Diamictites are defmed as poorly sorted polymictic (paraconglomerates), conglomerates and breccias that contain less than 10 percent pebbles and a wide range of clast size and shapes. They contain rounded and angular fragments of carbonate, chert, quartz, volcanic and other rocks. During sedimentation, laminations near the clasts are bend down beneath them and arch over them. Diamictites are associated with rhythmites, cap carbonates and Neoproterozoic Rapitan banded iron formations in north and south America, Africa, Europe, Asia and Australia.
The deposition of diamictites is caused by Neoproterozoic interglacial and glacial events by wich the Earth became ice- covered from pole to pole along with rifting, glaciation and iron mineralization in the intracontinental rifts. In Iran, these glacial facies are observed at Bafq mining district and Jalal Abad iron deposit. At mishdavan icon deposit, dianuctites occur as 20 to 30 meters of massive and angular paraconglomerate and breccia overlying keratophyres and banded iron formations. At Jalal Abad iron deposit, a typical sequence of diamictites, rhythmites and cap carbonates, are observed, indicating rising the sea level transgression and iron mineralization, during glacio-marine deposition.The diamictic facies of Iran is comparable to those of Oman glacial facies (Huqf and Dhufar groups) and indicate the Neoproterozoic Rapitan model of banded iron formations in the stratigraphic column of Iran.

Subject List : Diamictites