(U-Th)/He thermochronology of metallic ore deposits in the Liaodong Peninsula: Implications for orefield evolution in northeast China
(U-Th)/He thermochronology of metallic ore deposits in the Liaodong Peninsula: Implications for orefield evolution in northeast China
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辽东半岛金属矿床(U-Th)/He热年代学：对中国东北地区矿田演化的启示
DOI：
10.1016/j.oregeorev.2017.11.025
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发表时间：
2018
影响因子：
3.3
通讯作者：
Liekun Yang
中科院分区：
文献类型：
--
作者：
Yinzhi Wang;Fei Wang;Lin Wu;Wenbei Shi;Liekun Yang
辽东半岛是中国东北重要的多金属矿开采区，但目前缺乏精确的热年代学数据来有效地约束该矿田的演化。在辽东半岛青城子和武隆矿田采集了15个花岗岩样，进行了锆石和磷灰石的(U-Th)/He研究。青城子矿田单粒哲和AHe年龄分别为73 ~ 166 Ma和22 ~ 48 Ma，武隆矿田单粒哲和AHe年龄分别为42 ~ 88 Ma和21 ~ 56 Ma。有些样品产生分散的年龄。综合分析表明，U和Th的非均质分布、辐射损伤和冷却速率是引起he年龄层色散的主要原因，而AHe年龄层色散主要是由前两个因素引起的。根据氦年龄，计算了两个矿田不同时期的平均掘冷速率及剥蚀作用，青城子矿田为4.3 km，武隆矿田为4.7 km。利用流体包裹体均一温度和矿化度估算成矿深度，青城子铅锌矿床和金银矿床成矿深度分别为1.5 ~ 3.2 km和1.0 ~ 2.2 km，武隆金矿床成矿深度为2.1 ~ 3.1 km。这些结果远小于总剥蚀量，表明矿体已被严重侵蚀。结合两个矿田的氦年龄分布，模拟的低t热史表明，辽东半岛在早白垩世（约135 ~ 115 Ma）、晚白垩世末至早始新世（约70 ~ 50 Ma）和晚始新世至渐新世（约38 ~ 26 Ma）经历了3个相对快速的冷却阶段。最后一个冷却阶段影响了两个矿田，代表了一个相对强烈的构造活动时期。最后，将这些结果与邻近胶东半岛的研究结果进行了比较。研究表明，辽东半岛矿田的降温过程与胶东半岛的降温过程基本一致。这些资料为进一步研究东北矿田演化提供了有价值的资料。
The Liaodong Peninsula is an important region where polymetallic ores are mined in northeast China, but precise thermochronological data needed to effectively constrain the evolution of this orefield are presently lacking. For this study, fifteen samples of granitoid rocks were collected from the Qingchengzi and Wulong orefields located in the Liaodong Peninsula to undertake (U-Th)/He study of zircon and apatite. Single-grain ZHe and AHe ages from the Qingchengzi orefield range from 73 to 166 Ma and from 22 to 48 Ma, respectively, whereas single-grain ZHe and AHe ages from the Wulong orefield range from 42 to 88 Ma and from 21 to 56 Ma, respectively. Some samples yield dispersed ages. Comprehensive analyses indicate that the main causes of the dispersion in the ZHe ages are heterogeneous distribution of U and Th within the crystals, radiation damage and cooling rates, whereas the dispersion in the AHe ages is primarily due to the first two factors. Based on the helium ages, we calculate the average exhumation and cooling rates of the two orefields during different periods and the associated denudation, which are 4.3 km for the Qingchengzi orefield and 4.7 km for the Wulong orefield. The mineralization depths are estimated using homogenization temperature and the salinity of fluid inclusions, and are calculated to be 1.5–3.2 km and 1.0–2.2 km for the Qingchengzi Pb-Zn and Au-Ag deposits, respectively, and 2.1–3.1 km for the Wulong Au deposit. These results are much less than the total denudation, suggesting that the orebodies have been heavily eroded. In conjunction with the distribution of the helium ages, the modeled low-T thermal histories of the two orefields reveal that the Liaodong Peninsula experienced three stages of relatively rapid cooling during the Early Cretaceous (ca. 135–115 Ma), from the end of the Late Cretaceous to the Early Eocene (ca. 70–50 Ma) and from the Late Eocene to the Oligocene (ca. 38–26 Ma). The last stage of cooling affected both orefields and represents a period of relatively intense tectonic activity. Finally, these results are compared with those of previous studies from the adjacent Jiaodong Peninsula. This discussion shows that the cooling experienced by the orefields in the Liaodong Peninsula is largely consistent with that experienced by the Jiaodong Peninsula. These data provide valuable information for further studies of the evolution of orefields in northeast China.
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DOI：
--
发表时间：
2005
期刊：
The European Physical Journal B
影响因子：
--
作者：
B. McInnes;N. Evans;K. Deckart;F. Fu;S. Garwin;E. Belousova;W. Griffin;Alfredo N. Bertens;D. Sukarna;S. Permanadewi;R. L. Andrew
通讯作者：
B. McInnes;N. Evans;K. Deckart;F. Fu;S. Garwin;E. Belousova;W. Griffin;Alfredo N. Bertens;D. Sukarna;S. Permanadewi;R. L. Andrew
影响因子：
5
作者：
R. A. Wolf;K. Farley;L. Silver
通讯作者：
R. A. Wolf;K. Farley;L. Silver
影响因子：
1.8
作者：
Yang Li
通讯作者：
Yang Li
DOI：
--
发表时间：
2010
期刊：
Journal of Jilin University
影响因子：
--
作者：
JI Zhao-jia
通讯作者：
JI Zhao-jia
DOI：
10.1086/378486
发表时间：
2003-11
期刊：
The Journal of Geology
影响因子：
--
作者：
Jian-wei Li;P. Vasconcelos;Jun Zhang;Mei‐Fu Zhou;Xiaojun Zhang;Feng-Hua Yang
通讯作者：
Jian-wei Li;P. Vasconcelos;Jun Zhang;Mei‐Fu Zhou;Xiaojun Zhang;Feng-Hua Yang