پترولوژي تراورتن هاي جنوب ميلاجرد (شمال غرب اردستان، اصفهان)

Petrology of South Milajed Travertines (N-W Ardestan. Esfahan)

N-W Ardestan travertines are located south of Milajerd village and north-east of Esfahan city. The region belongs to Uromia-Dokhtar belt zone. Morphologic evidences imply that the travertines are Fissure-Ridge type and are related to the Quaternary age. Petrology and geochemistry evidences indicate that most of these resources are thermogenic. Fabric and texture characteristic of these sediments emphasize the active presence of micro organisms and biological activities with travertine sedimentation simultaneously. The presence of lamination in travertine is due to alternative seasonally/daily growth. Most of these sediments are seen on/in the 1 to 2 kilometers of the active fault zones. With regard to the process of these faults, the generating agent of travertines is the local tension in fault regions. The geological evidences shows that these rocks occurred in a high geogradiant environment and due to the tectomagmatic activities circulation of magmatic and meteorite waters in depth and represented on surface by the faults and fractures in the form of hot springs causing the formations of travertines in springs and large faults trends.