New　zircon　LA-ICP-MS　U-Pb　ages,　Sr-Nd　isotopic　data,　and　whole-rock　major　and　trace　element　data　from　Early　Cretaceous　volcanic　rocks　are　reported　for　the　Jiwa　area　in　the　southern　central　Lhasa　Terrane　of　Tibet.　These　mainly　silicic　volcanic　rocks　and　subordinate　intermediate-basic　volcanic　rocks　have　long　been　considered　to　be　Pliocene　(Wuyu　Group)　or　Eocene　(Pana　Formation)　in　age.　However,　our　new　zircon　U-Pb　ages　constrain　the　timing　of　eruption　to　the　Early　Cretaceous　(124.6　+/-　1.6-126.1　+/-　1.1Ma);　thus,　we　have　redefined　these　volcanic　rocks　as　the　Lower　Cretaceous　Zenong　Group.　The　silicic　volcanic　rocks　feature　high-K　calc-alkaline　to　shoshonitic　compositions　and　are　mostly　strongly　peraluminous,　rich　in　Rb,　Th,　and　light　rare　earth　elements　(LREEs),　and　depleted　in　Nb,　Ta,　P,　and　Ti.　They　are　also　characterized　by　negative　whole-rock　epsilon　Nd(t)　values　(-9.1　to　-13.1)　and　variable　Sr-87/Sr-86　ratios.　Thus,　the　geochemical　and　zircon　U-Pb　age　data　of　the　Jiwa　volcanic　rocks　suggest　that　these　rocks　are　associated　with　a　continental　arc　and　are　mostly　likely　derived　from　anatexis　of　ancient　continental　crustal　material　and　minor　basalt-derived　melts.　The　discovery　of　Early　Cretaceous　volcanic　rocks　in　the　southern　central　Lhasa　Terrane　extends　the　duration　of　magmatism　triggered　by　southward　subduction　of　the　Bangong-Nujiang　oceanic　lithosphere　from　the　Late　Jurassic　to　the　Early　Cretaceous.　The　spatial　distribution　of　magmatism　is　also　extended　70-80km　to　the　south.　The　Lower　Cretaceous　volcanic　rocks　in　the　Jiwa　area　are　proposed　to　be　a　result　of　bi-directional　subduction,　with　southward　subduction　of　the　Bangong-Nujiang　oceanic　crust　and　northward　subduction　of　the　Yarlung　Zangbo　oceanic　crust.　The　bi-directional　subduction　of　the　oceanic　lithosphere　and　gravitational　sinking　led　to　slab　retreat　at　ca.　125Ma.　The　roll-back　of　the　slab　would　have　then　led　to　back-arc　extension　and　asthenospheric　upwelling.　The　subduction-induced　decompression　melting　of　the　mantle　led　to　the　generation　of　widespread　rhyolitic　volcanism　with　continental　arc　geochemical　signatures.