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对宁镇地区安基山岩体主要岩石类型花岗闪长斑岩的SHRIMP锆石U-Pb定年结果表明,安基山岩体的花岗闪长斑岩SHRIMP锆石U-Pb年龄为(106.9±0.9)Ma,代表了岩体形成年龄,岩体形成于早白垩世晚期;安基山岩体的形成明显晚于铜陵等地高钾钙碱性中酸性侵入岩形成时代,揭示出宁镇地区中酸性钙碱性岩浆活动及其成矿响应是中生代长江中下游成矿带大规模岩浆活动的另一期成岩成矿事件;宁镇地区铜多金属成矿作用在时间、空间和成因上与107Ma左右的钙碱性中酸性岩浆活动有密切的联系,区内成岩成矿作用是一个连续的过程;宁镇地区钙碱性中酸性岩浆活动的地球动力学背景对应中国东部中生代岩石圈拆沉减薄事件;长江中下游地区岩石圈拆沉从130Ma左右开始,可能一直持续到107Ma以后.
SHRIMP zircon U-Pb dating of the main rock type granodiorite porphyry in the Anji Mountain pluton in Ningzhen area shows that the SHRIMP zircon U-Pb age of the granodiorite porphyry in the Anji Mountain pluton is (106.9 ± 0.9) Ma, representing the age of rock mass. The rock mass formed in the early Early Cretaceous. The formation of the Anji rock mass was later than that of the high-K calc-alkaline intermediate-acid intrusive rocks in Tongling and other places, Acidic calc-alkaline magmatism and its metallogenic response are another stage of diagenetic and ore-forming events of the Mesozoic large-scale magmatic activity in the metallogenic belt of the middle and lower reaches of the Yangtze River. The metallogenic process of copper polymetallic in Ningzhen area is similar in time, space and genesis to 107 Ma The magmatic activity of calc-alkaline medium-acidic magmatism in Ningde area is closely related to the magmatic activity of calc-alkaline medium and the diagenesis and mineralization in the area are a continuous process. The geodynamic background of calc-alkaline magma activity in Ningzhen area corresponds to the Mesozoic lithospheric delamina- tion and sedimentation in eastern China Thin events; lithosphere delamination in the middle and lower reaches of the Yangtze River began around 130Ma, possibly lasting to 107Ma.