A genetic interpretation on The Origin of Hormoz Salt Formation

Category Other
Group GSI.IR
Location Proceed ings of Symposium on DIAPIRISM
Holding Date 11 March 2008
     The geographical-temporal distribution of the sedimentary and magmatic rocks in the interval of Upper Proterozoic-Carnbrian in Iran and NE-Arabian Platform with stress on the Horrnoz Salt Formation (HSF) is briefly reviewed. The mineral resources and fuels, hosted in these rocks, i.e., rock salt and K-salt, magmatic and sedimentary phosphates, zinc, gold, radioactives, REE and hydrocarbons are genetically interpreted under the light of a proposed genetic model, i.e, "Volcanogenic model".
According to the model, the extended alkaline magmatism in the subject (including the HSF) is the initial source for the minerals and fuels. The alkaline magma, rich in fumaroles with Na, K, Cl, P, Fe, Pb, Zn, Au, U, REE H2S, CO2, CH4 and some other components, introduces these mineral materials into the sedimentary basin (rift? basin). The discharterial from magma into the sedimentary basin takes place from the volcanic vents and/or the exhalation foci. The basinal water becomes abnormally rich in the ore forming ions, first locate around the vents and foci and gradually in the whole basin. The precipitation of Na, K, Mg salts will occur near the emanation foci just at the bottom of the basin due to saturation (not necessarily with evaporation process). The environmental parameters like Eh, PH, T, depth, evaporation, water movements like currents, tides, upwelling, etc. may provide different conditions for precipitation of Fe, Pb, Zn, Au, Ea, U, REE, P and evaporites as sulfides, cloridesoxides, sulphates etc. The abnormal amounts of P, CH4, H2s, CO2 and some other componetns may be consumed as nutrients for bioagents and cause the expantion of their populations, the mortality of which may produce the potentiality for sedimentary phosphates, hydrocarbons precursors, coal, sulfides etc.
Huge masses of exhalative Fe oxides with apatite, U, REE may precipitate in association or close to the submarine volcanic vents with alkaline affinity or its exterm differentiation product, i.e., carbonatite vents. As salt piles, according to this model, form around the exhalation foci. one can expect a rough and uneven morphology of salt masses on the basins floor during sedimentation. The huge piles may make up the "initial-core" for the later on diapirs which may grow up during later tectonic events.
The HSF, its synchroneous rocks and their enclosing mineral and fuel resources in Upper Proterozoic-Cambrian are genetically evaluated under the light of the "Volcanogenic model".