穿地壳岩浆系统改变岩石圈流变和热结构  

Trans-crustal magmatic system changes lithospheric rheology and thermal structure

作　　者：周瑶琪[1] 刘婕 张鑫 刘朋 周腾飞 李孙义 陈扬 ZHOU Yaoqi;LIU Jie;ZHANG Xin;LIU Peng;ZHOU Tengfei;LI Sunyi;CHEN Yang(School of Geosciences and technology in China University of Petroleum(East China),Qingdao 266580,China;Shandong Energy Group South America Company Limited,Qingdao 266000,China)

机构地区：[1]中国石油大学(华东)地球科学与技术学院,山东青岛266580 [2]山东能源集团南美有限公司,山东青岛266000

出　　处：《中国石油大学学报（自然科学版）》2024年第1期1-12,共12页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：山东能源集团有限公司重大项目(SNKJ2022A06-R23)。

摘　　要：以山东东部穿地壳岩浆系统为例,通过研究岩石圈流变结构和热结构,结合已有野外探勘及地球物理数据,对山东东部地壳演变进行还原和解释,并且进一步建立穿地壳岩浆系统的岩浆深部热效应模型,考察岩石圈深部动力学演化机制。初步估算靶区地温,对山东东部地区超过6 km岩石圈结构及其地热储集体展布进行预测,进一步阐述山东东部深部地热储集体形成理论模型。结果表明:华北克拉通太古宙形成具有稳定刚性的陆壳,花岗岩主要以未变质或浅变质的表壳岩为主;中生代以来受华北克拉通基底不稳定,经历强烈构造-岩浆活动,产生强烈构造变形,岩石圈地幔发生拆沉和置换;晚中生代山东东部由于深部构造活动剧烈,穿地壳岩浆沿大型断裂上涌至喷出地表,伴随热隆效应及同化混染;岩石圈厚度减薄,地幔上涌至上、中地壳,伴随表壳岩熔融,其中富含不相容的放射性元素随岩浆再次上涌,不断向浅部地壳输送生热的放射性元素,从而使得岩石圈热结构及流变结构改变。This paper takes the transcrustal magmatic system in eastern Shandong as an example.By studying the rheological structure and thermal structure of the lithosphere,combined with the existing field exploration and geophysical data,the crustal evolution in eastern Shandong was reduced and explained,and the magma deep thermal effect model of the transcrustal magmatic system is further established to understand the deep dynamic evolution mechanism of the lithosphere.The geothermal temperature of the target area is preliminarily estimated,and the lithospheric structure and the distribution of geothermal reservoirs above 6 km in eastern Shandong are predicted,and the theoretical model of the formation of deep geothermal reservoirs in eastern Shandong is further elaborated.The results show that the North China Craton formed a stable and rigid continental crust in the Archean,and the granites are mainly composed of non-metamorphic or low-metamorphic supracrustal rocks.Since the Mesozoic,the basement of the North China Craton has been unstable and experienced strong tectono-magmatic activities,resulting in strong tectonic deformation,delamination and replacement of the lithospheric mantle.In the late Mesozoic,due to the intense deep tectonic activity in the eastern part of Shandong Province,the transcrustal magma surged up to the surface along the large fault,accompanied by the thermal uplift effect and assimilation and contamination.The thickness of the lithosphere is thinned,and the mantle rises to the upper and middle crust.With the melting of the supracrustal rock,the incompatible radioactive elements are re-upwelled with the magma,and the heat-generating radioactive elements are continuously transported to the shallow crust,thus changing the thermal structure and rheological structure of the lithosphere.

关 键 词：穿地壳岩浆系统 岩石圈热结构 岩石圈流变结构 地热能 

分 类 号：P54[天文地球—构造地质学]