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金厂铜金矿床东部及外围广泛出露一套中酸性火山岩系,岩性为流纹质、英安质凝灰岩及晶屑凝灰岩。作为火山岩主体的流纹质凝灰岩,其w(SiO2)为66.32%～75.56%,w(Al2O3)为12.09%～15.64%,总碱量w(Na2O+K2O)为6.40%～7.91%,且CaO>MgO,Na2O>K2O,Al2O3/(CaO+K2O+Na2O)<1.1,属中酸性准铝质钙碱性岩石系列。火山岩样品TY-6的锆石谐和年龄为(210.4±1.6)Ma;TY-7的锆石谐和年龄为(210.0±1.9)Ma,显示火山岩成岩时代为印支晚期。结合岩性特征,说明研究区火山岩应归属于三叠世罗圈站组(T3l)。火山岩岩石化学特征表明研究区火山岩为地壳部分熔融产物。罗圈站组火山岩可能标志着区域构造由兴蒙造山结束并向环太平构造转换。而金厂铜金矿床成矿时代为118.6Ma,说明金丰度较高的罗圈站组火山岩(210Ma左右)其原始岩浆可能存在着金的预富集,且可能为金厂铜金矿床成矿提供部分物质。但二者不具有直接的成因联系。
In the east and outside of the Jinchang copper-gold deposit, a series of medium-acidic volcanic rocks are widely exposed. The lithology is rhyolitic, quartzitic tuff and crystal tuff. The rhyolitic tuff, which is the main body of volcanic rocks, has w (SiO2) of 66.32% -75.56%, w (Al2O3) of 12.09% -15.64% and total alkali content of w (Na2O + K2O) of 6.40% ~ 7.91% > MgO, Na2O> K2O, Al2O3 / (CaO + K2O + Na2O) <1.1. The zircon zircon dating of TY-6 was (210.4 ± 1.6) Ma and that of TY-7 was (210.0 ± 1.9) Ma, indicating that the volcanic diagenetic period was the late Indosinian. Combined with lithological characteristics, the volcanic rocks in the study area should belong to the Triassic Luojuan formation (T3l). Volcanic rocks Petrochemical characteristics indicate that volcanic rocks in the study area are part of crustal melting products. The volcanic rocks in the Luohuozhan Formation may indicate that the regional structure was ended by the Xingmeng orogen and converted to the Central Pacific. While the Jinchang copper-gold deposit metallogenic epoch is 118.6Ma, indicating that there may be pre-enrichment of gold in the original magma of the Luohuodazhan volcanic rock (about 210Ma) with high gold abundance, and may be a gold mineralization in the Jinchang copper-gold deposit Provide some material. But the two do not have a direct causal link.