Western Block
... that the oldest part of the Western Block of the North China Craton formed 2.7 billion years ago?
... that the oldest part of the <b id="mwBdw"><a href="./Western_Block_of_the_North_China_Craton" id="mwBd0" rel="mw:WikiLink" title="Western Block of the North China Craton">Western Block</a></b> of the <a href="./North_China_Craton" id="mwBd4" rel="mw:WikiLink" title="North China Craton">North China Craton</a> formed 2.7<span id="mwBd8" typeof="mw:Entity"> </span>billion years ago?