▁Pro ter oz o ic . ▁ ▁Earth qu akes ▁▁ ▁The ▁collision ▁of ▁India ▁with ▁the ▁rest ▁of ▁Asia ▁has ▁led ▁to ▁se ism ic ▁activity ▁throughout ▁western ▁China , ▁particularly ▁in ▁Tib et ▁and ▁the ▁Y unn an , ▁X in ji ang , ▁S ich uan , ▁G ans u ▁and ▁Q ing hai ▁provinces . ▁However , ▁these ▁regions ▁in ▁comparison ▁with ▁Eastern ▁China ▁have ▁a ▁low ▁population ▁density . ▁These ▁areas ▁also ▁in ▁general ▁have ▁poor er ▁transport ▁and ▁building ▁codes . ▁Through out ▁China ▁poor ▁building ▁codes ▁increases ▁the ▁damage ▁and ▁loss ▁of ▁life ▁from ▁earth qu akes . ▁ ▁China ▁has ▁been ▁the ▁location ▁of ▁some ▁of ▁the ▁most ▁dead ly ▁earth qu akes ▁in ▁history . ▁H undred s ▁of ▁thousands ▁of ▁people ▁were ▁killed ▁by ▁magnitude ▁ 8 . 0 ▁earth qu akes ▁in ▁ 1 3 0 3 ▁in ▁Hong d ong ▁and ▁ 1 5 5 6 ▁in ▁Sh a an xi . ▁This ▁Sh a an xi ▁earth qu ake ▁killed ▁about ▁ 8 3 0 , 0 0 0 ▁people , ▁many ▁dying ▁with ▁the ▁coll ages ▁of ▁their ▁under ground ▁homes ▁built ▁into ▁lo ess ▁banks ▁and ▁cl iffs . ▁The ▁ 2 0 th ▁century ▁saw ▁ 2 7 3 , 4 0 0 ▁people ▁killed ▁in ▁the ▁ 1 9 2 0 ▁H ai y uan ▁earth qu ake ▁and ▁a ▁magnitude ▁ 8 . 6 ▁earth qu ake ▁in ▁ 1 9 5 0 , ▁the