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作 者:刘钧枢
机构地区:[1]河南省地矿厅第二水文地质工程地质队,河南450100
出 处:《西安地质学院学报》1994年第4期48-54,共7页
摘 要:根据对Z_(37-2)孔的孢粉分析结果表明,郑州地区,自全新世以来,气候经历三次较大的波动,先是气候开始转暖,气温不高,温凉半湿润;二是气候继续升高,达到“最适宜”气候期,温暖湿润;最后是气候再度下降,降水减少,温凉偏干.本区气侯变化规律,与北京地区基本符合.依据气侯地层学的观点,并结合放射性碳年代测定,本区的全新世地层可以划分为三期:即全新世早期(距今11000~7500a),全新世中期(距今7500~2500a),全新世晚期(距今2500a至今).The sporopollen analysis results for well drilling No. Z37-2are indicated that the climate in the Zheng zhou area since the Holocene underwen three considerable fluctuations: firstly, the climate was staled change over to warm, air temperature was lower, the climate was warm-cool and humid: afterwards, the air temperature went on increase, most suitable climate period has arisen, the climate was warmhumid: lastly, the air temperture was lower once again, there has been a decrease in the precipitation , the climate was warm-cool and was on the arid side. The climate variation low in this area was confomed mainly to it in peking area.According to the stratigraphy viewpoint and based on the radio-carbon isotope age dating, the Holocene stratum may have been dirided in the three periods: early Holocene (11 000~7500 a B. P. )middle Holocene (7 500~2 500 a B. P.)later Holocene(2 500 a B. P. at Present).
分 类 号:P467[天文地球—大气科学及气象学] Q913.663.2[天文地球—古生物学与地层学]
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