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The Dahuiyeh (Zarand) earthquake of 2005 February 22 in central Iran: reactivation of an intramountain reverse fault 总被引:3,自引:0,他引:3
184.
The Cone-in-Cone Structure and Its Origin 总被引:1,自引:0,他引:1
Morphostructural investigation of carbonate cone-in-cone formations allows to conclude that they belong to self-organizing (dissipative, according to I. Prigogine's terminology) systems of the geological past formed in a thermogradient field at the expense of energy of heat and mass transfer (Prigogine and Stengers, 1984). First, the fluid-convective metasomatic hypothesis unites and reconciles the most well-known hypotheses that previously seemed to be incompatible and transforms them to rather consistent particular cases of a more intricate multistage geological phenomenon. Second, it helps to identify the morphologically and genetically analogous noncarbonate structures that mimic biogenic ones. The probable indicative role of cone-in-cone structure in the mapping of fluid-conducting systems is a consequence of the proposed hypothesis. 相似文献
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Origin of Geochemical Variability by Arc-Continent Collision in the Biru Area, Southern Sulawesi (Indonesia) 总被引:1,自引:0,他引:1
Analyses of igneous rocks from the Eocene calc-alkaline andMiocene potassic volcanic arc in southwest Sulawesi indicatethat magmas became more heterogeneous in their trace elementand PbSrNd isotopic signature following the collisionof the Buton microcontinent with the arc at 相似文献
187.
Data of hydrological and hydrochemical observations conducted in August 2000 at Lake Seliger and its major tributaries are presented. The analyzed characteristics included: O2, H2S, CH4, microelements; mineral and organic compounds of P and N, ionic composition components (HCO3
–, Cl–, Na+, K+, dry residue, pH; color index, electrical conductivity. Bottom sediment samples were analyzed for microelement concentrations, CH4, oil hydrocarbons. The influence of the basin on the ecological state of the lake was assessed, and tendencies in the evolution of its ecosystem are analyzed. It is shown that the ecological conditions of the lake has not changed significantly since 1960–1991, however, nutrient concentrations in the lake water was found to increase. 相似文献
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