地质通报
地質通報
지질통보
Geological Bulletin of China
2015年
10期
1869-1877
,共9页
陈树旺%张海华%郑月娟%卞雄飞%张健%苏飞%公繁浩%黄欣%甄甄
陳樹旺%張海華%鄭月娟%卞雄飛%張健%囌飛%公繁浩%黃訢%甄甄
진수왕%장해화%정월연%변웅비%장건%소비%공번호%황흔%견견
碎屑锆石LA-ICP-MSU-Pb年龄%林西组%晚二叠世%科右中旗—突泉地区
碎屑鋯石LA-ICP-MSU-Pb年齡%林西組%晚二疊世%科右中旂—突泉地區
쇄설고석LA-ICP-MSU-Pb년령%림서조%만이첩세%과우중기—돌천지구
detrital zircon LA-ICP-MS U-Pb ages%Linxi Formation%Late Permian%Horqin Right Wing Middle Banner-Tuquan area
内蒙古科右中旗—突泉地区出露一套缺少化石、遭受接触变质作用的巨厚层碎屑岩,其先后被划归为早二叠世索伦组、晚二叠世林西组、下寒武统.取自该套地层砂岩样品的碎屑锆石LA-ICP-MS U-Pb定年数据表现为2个主要年龄区间:255~354Ma,峰值年龄为263Ma和283Ma;413~529Ma,峰值年龄为485Ma.另有5颗锆石的年龄值分别为625Ma、965Ma、1372Ma、1707Ma、1727Ma.263Ma的峰值年龄限定了该套地层的沉积下限应为晚二叠世,结合区域地层对比,认为是晚二叠世林西组.该地层年代为突泉盆地下伏第二低阻层为林西组的推断提供了年代学证据.
內矇古科右中旂—突泉地區齣露一套缺少化石、遭受接觸變質作用的巨厚層碎屑巖,其先後被劃歸為早二疊世索倫組、晚二疊世林西組、下寒武統.取自該套地層砂巖樣品的碎屑鋯石LA-ICP-MS U-Pb定年數據錶現為2箇主要年齡區間:255~354Ma,峰值年齡為263Ma和283Ma;413~529Ma,峰值年齡為485Ma.另有5顆鋯石的年齡值分彆為625Ma、965Ma、1372Ma、1707Ma、1727Ma.263Ma的峰值年齡限定瞭該套地層的沉積下限應為晚二疊世,結閤區域地層對比,認為是晚二疊世林西組.該地層年代為突泉盆地下伏第二低阻層為林西組的推斷提供瞭年代學證據.
내몽고과우중기—돌천지구출로일투결소화석、조수접촉변질작용적거후층쇄설암,기선후피화귀위조이첩세색륜조、만이첩세림서조、하한무통.취자해투지층사암양품적쇄설고석LA-ICP-MS U-Pb정년수거표현위2개주요년령구간:255~354Ma,봉치년령위263Ma화283Ma;413~529Ma,봉치년령위485Ma.령유5과고석적년령치분별위625Ma、965Ma、1372Ma、1707Ma、1727Ma.263Ma적봉치년령한정료해투지층적침적하한응위만이첩세,결합구역지층대비,인위시만이첩세림서조.해지층년대위돌천분지하복제이저조층위림서조적추단제공료년대학증거.
A set of thick layer rocks, which lack fossils and suffered from contact metamorphism, have been recognized as Early Perm-ian Suolun Formation, Late Permian Linxi Formation and Lower Cambrian strata in Horqin Right Wing Middle Banner-Tuquan ar-ea, Inner Mongolia. Age data of 52 detrital zircons obtained from LA-ICP-MS dating show that the detrital zircon U-Pb ages could be divided into two parts:the young ages varying from 255Ma to 354Ma with the peak age of 263Ma and 283Ma, and the other ages concentrated in the range of 413-529Ma with the peak age of 485Ma. The authors also obtained some old data such as 625Ma, 965Ma, 1372Ma, 1707Ma, and 1727Ma. Compared with the age of 242Ma of the granite which was intruded into the strata, the age of 263Ma suggests that the strata could be assigned to the Late Permian Linxi Formation. The data of age characteristics that represent the provenance of the strata and the collision of the Siberian and North China plates in Late Permian are also discussed in this paper. In addition, the stratigraphic age gives evidence to support the assumption that the Late Permian Linxi Formation occurred beneath Tuquan Basin as"second low resistivity layer".
