تركيب ژئوشيميايي خاكستر زغال سنگ هاي حوضه زغالي البرز

Geochemical Properties of coals in coal fields of Alboiz basin

The Alborz coal basin is located at north ranges of Iran. Three typical coal fields of Shahroud, Zirab and Lushan from well-known geological setting of Alborz coal basin chosen to cover a range of rank were used to compare and con­trast to conventional ash measurement method to improving of new made dual energy gamma-ray.device. Conventional method is based on the measuring of ash percent by analytical balance. The dual energy gamma-ray device is based on the dual energy gamma-rays transmission. A geochemical study in coal seams of the Upper Triassic to Middle Jurassic sed­iments of so-called Shemshak formation was undertaken to determine what fac­tors control coal quality and ash content. During this study several samples were collected from the three typical coalfields and were analyzed for major and some trace elements by X-ray floursences (XRF). The abundance of these elements was discussed in relation to local geological conditions. Relationships between various elements have been identified from scatter diagrams and reflect genetic associations. The average of some major and trace elements contents of these samples show higher concentration when compared to the range for most usual coals in the world, while the others agree with global ranges.