| Abstrakt: |
The present review of the pyrometamorphic rocks (varicolored marble) from Maqarin, Suweileh, and Daba-Siwaqa Khushym Matruck areas, Jordan, demonstrates the value of the identified unusual high- and low-temperature minerals in acting as a sink for hazardous elements. Pyrometamorphism has produced minerals with unique chemistry, substitutions, solid solution series, and strong enrichment in the light isotopes of oxygen and carbon. The high-temperature minerals are the result of in situ combustion of the bituminous marl precursor enriched with reduced sensitive elements (RSE: Zn, Cd, Fe, Ni, Cu, V, Cr, Fe, Mo, As, Co, U). The pyrometamorphic rocks are characterized by unusual textures and structures in addition to the ultrahigh-temperature minerals. Features as the brecciated and highly fractured and molten rocks, polygonal jointing, explosion breccia and fragments, and many others suggest another triggering event of combustion than the spontaneous ignition related to the bituminous marl (oil shale) and tectonism along the Rift Valley. Different meteoritic impacts/cosmic air bursts are suggested as possible triggering events between the periods of Waqf As Suwwan (Post Early Eocene) and Tall el-Hammam (~ 3600 years ago) meteoritic impact episodes. The highly alkaline circulating water in the pyrometamorphic rocks has led to the liberation and mobilization of trace elements from the source rock. The low-temperature minerals with high concentrations of RSE were the result of crystallization from these waters along the weakness zones and fractures of the altered bituminous marl, varicolored marble, and travertine. [ABSTRACT FROM AUTHOR] |
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