内蒙古满都拉二叠纪海绵生物丘的发现及意义

在内蒙古自治区达尔罕茂明安联合旗北部满都拉地区进行 1/5万区域地质调查过程中 ,首次于阳新统哲斯组中识别出小型海绵生物丘。海绵生物丘发育于华北板块北部活动边缘晚华力西褶皱造山带上 ,分布于近东西向延伸的大石寨组火山岛弧的两侧 ,南侧在包特格、满都拉苏木等地以小型海绵丘为特征 (局限弧后盆地边缘海绵丘 ) ;北侧发育了规模较大的哲斯敖包生物礁 (开阔台地边缘礁 )。通过对海绵及其他生物化石的古生态分析 ,结合沉积特征探讨了该区阳新世的古地理环境

DISCOVERY OF THE PERMIAN SPONGE MOUNDS IN MANDULA,INNER MONGOLIA

Recently, the Permian sponge mounds were discovered in the Zhesi Formation at Mandula, Daerhanmaominganlianhe Country, Inner Mongolia. The sponge mounds are mainly distributed on the southern and northern sides of Permian volcanic rocks (Dashizai Formation) on the northern margin of the North China Plate known as late Variscan orogenic belt. The smaller southern sponge mounds in Baotege and Mandulasumu found in the elosed back-arc basin. The is larger ones known as Zhesiaobo Reef were found on the margin of open platform. In the paper, the sedimentary features and the paleoecology of sponges and other fossils of the Zhesi Formation are analyzed and the paleogeograpic environments of the Yangxing Epoch are discussed.