北山北带园包山地区中酸性火山岩地球化学特征及锆石U-Pb年龄
|
摘要
北山北带园包山地区晚古生代中酸性火山岩以英安岩类为主,夹少量安山质火山岩。测得英安质凝灰岩锆石U-Pb年龄为315.9±3.4Ma,形成时代为晚石炭世,认为该套火山岩为上石炭统干泉组。该套岩石属于过铝质低钾-中钾钙碱性火山岩,轻稀土元素和大离子亲石元素相对富集,具有较弱的负Eu异常,高场强元素(Nb、Ti)及P元素明显亏损,表明其形成于大洋岛弧向大陆边缘弧过渡的构造环境。结合区域构造,认为北山北带地区晚石炭世古亚洲洋仍在俯冲,尚未闭合。
The Late paleozoic intermediate and acid volcanic rocks from Yuanbaoshan area in the northern part of Beishan orogenic belt are dominated by dacitic rock with a small amount of andesitic rock. Zircon U-Pb isotopic age 315.9±3.4 Ma was obtained in the dacitic tuff. It means that the age of rock formation is Late Carboniferous. The authors consider that this set of volcanic rocks belong to Upper Carboniferous Ganquan Formation. This set of volcanic rocks have the characteristics of ocean island arc and continental margin arc and are of low potassium-medium potassium calc-alkaline series, enriched relatively in light rare earth elements and large ion lithophile elements, and relatively depleted in high field strength elements, with unconspicuous Eu-negative anomaly. Combined with previous studies of regional structures and geochemistry of volcanic rocks, the authors consider that Ancient Asian Ocean still subducted and had not yet been closed in the north part of Beishan orogenic belt in Late Carboniferous.
The Late paleozoic intermediate and acid volcanic rocks from Yuanbaoshan area in the northern part of Beishan orogenic belt are dominated by dacitic rock with a small amount of andesitic rock. Zircon U-Pb isotopic age 315.9±3.4 Ma was obtained in the dacitic tuff. It means that the age of rock formation is Late Carboniferous. The authors consider that this set of volcanic rocks belong to Upper Carboniferous Ganquan Formation. This set of volcanic rocks have the characteristics of ocean island arc and continental margin arc and are of low potassium-medium potassium calc-alkaline series, enriched relatively in light rare earth elements and large ion lithophile elements, and relatively depleted in high field strength elements, with unconspicuous Eu-negative anomaly. Combined with previous studies of regional structures and geochemistry of volcanic rocks, the authors consider that Ancient Asian Ocean still subducted and had not yet been closed in the north part of Beishan orogenic belt in Late Carboniferous.
引文
[1]左国朝,何国琦.北山板块构造及成矿规律[M].北京:北京大学出版社,1990:1-226.
[2]左国朝,李茂松.甘蒙北山地区早古生代岩石圈形成与演化[M].兰州:甘肃科学技术出版社,1996:1-120.
[3]左国朝,刘义科,刘春燕.甘新蒙北山地区构造格局及演化[J].甘肃地质学报,2003,12(1):1-15.
[4]龚全胜,刘明强,李海林,等.甘肃北山造山类型及基本特征[J].西北地质,2002,35:28-34.
[5]龚全胜,刘明强,梁明宏,等.北山造山带大地构造相及构造演化[J].西北地质,2003,36(1):11-17.
[6]何世平,任秉琛,姚文光,等.甘肃内蒙古北山地区构造单元划分[J].西北地质,2002,35(4):30-40.
[7]何世平,周会武,任秉琛,等.甘肃内蒙古北山地区古生代地壳演化[J].西北地质,2005,38(3):6-15.
[8]黄增保,金霞.甘肃红石山地区白山组火山岩地质特征及构造背景[J].甘肃地质,2006,15(1):19-24.
[9]徐学义,何世平,王洪亮,等.中国西北部地质概论-秦岭、祁连、天山地区[M].北京:科学出版社,2008:1-347.
[10]刘雪亚,王荃.中国西部北山造山带的大地构造及其演化[J].地学研究,1995,28(1):37-48.
[11]陈高潮,魏仙祥,忤康林,等.内蒙古西部阿拉善右旗下石炭统白山组碎屑岩锆石LA-ICP-MS U-Pb测年及意义[J].地质通报,2011,30(6):955-961.
[12]卢进才,牛亚卓,魏仙祥,等.北山红石山地区晚古生代火山岩LA-ICP-MS年龄及其地质意义[J].岩石学报,2013,(29):2685-2694.
[13]牛亚卓,魏建设,史冀忠,等.甘肃北山地区北部上石炭统火山岩LA-ICP-MS锆石U-Pb年龄及其构造意义[J].地质通报,2013,32(11):1720-1727.
[14]Xiao W J,Mao Q G,Windley B F,et al.Paleozoic multiple accretionary and collisional processes of the Beishan orogenic collage[J].American Journal of Science,2010,310:1553-1594.
[15]金松桥.甘肃北山区下石炭统划分及其对比[J].地质学报,1974,2:159-174.
[16]内蒙古自治区地质矿产局.内蒙古自治区区域地质志[M].北京:地质出版社,1991.
[17]内蒙古自治区地质矿产局.内蒙古自治区岩石地层[M].武汉:中国地质大学出版社,1996.
[18]邹运鑫,曹霞,亢文丽.北山六陀山地区上石炭统白山组LA-ICP-MS锆石U-Pb年龄[J].西部资源,2015,5:65-68.
[19]贾元琴,赵志雄,许海,等.北山风雷山地区白山组流纹岩LA-ICP-MS锆石U-Pb年龄及构造环境[J].中国地质,2016,43(1):91-98.
[20]覃小锋,王宗起,张英利,等.桂西南早中生代酸性火山岩年代学和地球化学:对钦-杭结合带西南段构造演化的约束[J].岩石学报,2011,27(3):794-807.
[21]李可,张志诚,李建锋,等.内蒙古西乌珠穆沁旗地区中生代中酸性火山岩SHRIMP锆石U-Pb年龄和地球化学特征[J].地质通报,2012,31(5):671-684.
[22]张金凤,白新会.内蒙古苏尼特右旗温都尔庙地区早石炭世火山岩的发现及其构造意义[J].岩石学报,2016,32(9):2780-2792.
[23]张文.北山-阿拉善北缘晚古生代花岗岩及其构造意义[D].北京大学博士学位论文,2013:111-113.
[24]郑荣国,吴泰然,肖文交,等.北山北部双井子复式岩体年代学、地球化学及其大地构造意义[J].地质学报,2016,90(11):3153-3172.
(1)甘肃省地质局地质力学区域测试队. 1∶20万六驼山幅区域地质调查报告. 1979.
[2]左国朝,李茂松.甘蒙北山地区早古生代岩石圈形成与演化[M].兰州:甘肃科学技术出版社,1996:1-120.
[3]左国朝,刘义科,刘春燕.甘新蒙北山地区构造格局及演化[J].甘肃地质学报,2003,12(1):1-15.
[4]龚全胜,刘明强,李海林,等.甘肃北山造山类型及基本特征[J].西北地质,2002,35:28-34.
[5]龚全胜,刘明强,梁明宏,等.北山造山带大地构造相及构造演化[J].西北地质,2003,36(1):11-17.
[6]何世平,任秉琛,姚文光,等.甘肃内蒙古北山地区构造单元划分[J].西北地质,2002,35(4):30-40.
[7]何世平,周会武,任秉琛,等.甘肃内蒙古北山地区古生代地壳演化[J].西北地质,2005,38(3):6-15.
[8]黄增保,金霞.甘肃红石山地区白山组火山岩地质特征及构造背景[J].甘肃地质,2006,15(1):19-24.
[9]徐学义,何世平,王洪亮,等.中国西北部地质概论-秦岭、祁连、天山地区[M].北京:科学出版社,2008:1-347.
[10]刘雪亚,王荃.中国西部北山造山带的大地构造及其演化[J].地学研究,1995,28(1):37-48.
[11]陈高潮,魏仙祥,忤康林,等.内蒙古西部阿拉善右旗下石炭统白山组碎屑岩锆石LA-ICP-MS U-Pb测年及意义[J].地质通报,2011,30(6):955-961.
[12]卢进才,牛亚卓,魏仙祥,等.北山红石山地区晚古生代火山岩LA-ICP-MS年龄及其地质意义[J].岩石学报,2013,(29):2685-2694.
[13]牛亚卓,魏建设,史冀忠,等.甘肃北山地区北部上石炭统火山岩LA-ICP-MS锆石U-Pb年龄及其构造意义[J].地质通报,2013,32(11):1720-1727.
[14]Xiao W J,Mao Q G,Windley B F,et al.Paleozoic multiple accretionary and collisional processes of the Beishan orogenic collage[J].American Journal of Science,2010,310:1553-1594.
[15]金松桥.甘肃北山区下石炭统划分及其对比[J].地质学报,1974,2:159-174.
[16]内蒙古自治区地质矿产局.内蒙古自治区区域地质志[M].北京:地质出版社,1991.
[17]内蒙古自治区地质矿产局.内蒙古自治区岩石地层[M].武汉:中国地质大学出版社,1996.
[18]邹运鑫,曹霞,亢文丽.北山六陀山地区上石炭统白山组LA-ICP-MS锆石U-Pb年龄[J].西部资源,2015,5:65-68.
[19]贾元琴,赵志雄,许海,等.北山风雷山地区白山组流纹岩LA-ICP-MS锆石U-Pb年龄及构造环境[J].中国地质,2016,43(1):91-98.
[20]覃小锋,王宗起,张英利,等.桂西南早中生代酸性火山岩年代学和地球化学:对钦-杭结合带西南段构造演化的约束[J].岩石学报,2011,27(3):794-807.
[21]李可,张志诚,李建锋,等.内蒙古西乌珠穆沁旗地区中生代中酸性火山岩SHRIMP锆石U-Pb年龄和地球化学特征[J].地质通报,2012,31(5):671-684.
[22]张金凤,白新会.内蒙古苏尼特右旗温都尔庙地区早石炭世火山岩的发现及其构造意义[J].岩石学报,2016,32(9):2780-2792.
[23]张文.北山-阿拉善北缘晚古生代花岗岩及其构造意义[D].北京大学博士学位论文,2013:111-113.
[24]郑荣国,吴泰然,肖文交,等.北山北部双井子复式岩体年代学、地球化学及其大地构造意义[J].地质学报,2016,90(11):3153-3172.
(1)甘肃省地质局地质力学区域测试队. 1∶20万六驼山幅区域地质调查报告. 1979.