蒙古最南端与亚干—翁奇海尔罕变质核杂岩南倾拆离断层相关的糜棱岩表明早白垩世近水平的南南东向伸展，同运动期黑云母给出氩—氩年龄１２９Ｍａ－１２６Ｍａ，亚干－翁奇海尔罕变质核杂岩证明近来认识的东亚其它部分的晚中生代局部高应变伸展也发生在蒙古。翁奇海尔罕中生代变质作用（以前假定为前寒武纪）对南戈壁微大陆的存在提出了质疑 The mylonite associated with the southern declination of the sub-stem of the Yaqian-Wengheirhan metamorphic core at the southernmost tip of Mongolia indicates a near-horizontal south-south to eastward extension of the Early Cretaceous with an Argon-Argon age of 129 Ma -126Ma. The sub-ican-Wengheihai metamorphic core complex proved that the late Mesozoic local high-strain extensions that have recently been recognized in other parts of East Asia have also occurred in Mongolia. The Mesozoic metamorphism (previously assumed to be Precambrian) of the Wengqi Haerbin challenged the existence of the micro-continent in the South Gobi