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Travertine deposited around the Niangziguan karst springs was used as a new type of paleoclimate record in this study. Five stages of climate change in northern China from 200± ka to 36± ka before the present (B. P.) were reconstructed using the 18O and 13C isotope record of the travertine. Tendency of the change was towards a more arid climate. Coupling the temporal-spatial evolution of the springs with climate change, the hydrogeological evolution could be divided into four major periods since middle Pleistocene: (1)No spring period; (2)The initial period of spring outcropping as the predominant way of discharge; (3)The culmination period of spring development; and (4)The spring discharge attenuation period. The attenuation is partly related to the decrease of recharge as a result of the dry climate after 90±kaBP.
Travertine deposited around the Niangziguan karst springs was used as a new type of paleoclimate record in this study. Five stages of climate change in northern China from 200 ± ka to 36 ± ka before the present (BP) were reconstructed using the 18O and 13C isotope record of the travertine. Tendency of the change was towards a more arid climate. Coupling the temporal-spatial evolution of the springs with climate change, the hydrogeological evolution could be divided into four major periods since middle Pleistocene: (1) No spring period; (2) The initial period of spring outcropping as the predominant way of discharge; (3) The culmination period of spring development; and (4) The spring discharge attenuation period. The attenuation is partly related to the decrease of recharge as a result of the dry climate after 90 ± kaBP.