The discovery of the Jurassic OIB-type rocks in the Bangong Lake-Nujiang River suture zone

Nadong oceanic island is located in the western part of the Bangong Lake-Nujiang River suture zone. It occurs as an EW-trending belt in parallel with ophiolite and is associated with the Jurassic Muga Kangri Group. There exists transitional contact relationship between the OIB-type basalts and the flysch of the Muga Kangri Group. The OIB-type rocks are composed of basalt, basaltic conglomerate, limestone and/or reef limestone. Furthermore, these rocks display several volcanic eruption cycles. Geochemical data show that all the basalts have typical OIB features. Studies have also shown that a Jurassic ocean basin existed in the Bangong Lake-Nujiang River suture zone. Thus the discovery of the Nadong oceanic island plays a key role in revealing the evolutionary history of the Bangong-Nujiang Ocean during the Jurassic.