【摘 要】
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Geological and geochemical characteristics of cherts of the low|middle parts of the Jinchang Formation indicate that cherts are associated with hydrothermal sed
【出 处】
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Chinese Journal of Geochemistry
论文部分内容阅读
Geological and geochemical characteristics of cherts of the low|middle parts of the Jinchang Formation indicate that cherts are associated with hydrothermal sedimentation, but the middle|upper parts of the Jinchang Formation are mixed with normal sediments. The cherts are characterized by high Fe, As, Sb, Bi and Ga, low Al and total REE, negative Ce anomaly and HREE enrichment. Their {δ{}+{18}O} values show that the forming temperatures of the cherts range from 128 ℃ to 146 ℃.
Geological and geochemical characteristics of cherts of the low | middle parts of the Jinchang Formation indicate that cherts are associated with hydrothermal sedimentation, but the middle | upper parts of the Jinchang Formation are mixed with normal sediments. The cherts are characterized by high Fe, As, Sb, Bi and Ga, low Al and total REE, negative Ceanomaly and HREE enrichment. Their {δ {} + {18 } O } values show that the forming temperatures of the cherts range from 128 ° C to 146 ° C.
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