What can we infer about the ion diffusion region from oxygen ion observations?

Suiyan Fu1, Tong Wu1, Weijie Sun1, Shaojie Zhao2, Qiugang Zong1, Zuyin Pu3, Lun Xie3 and Xuzhi Zhou1, (1)Peking University, School of Earth and Space Sciences, Beijing, China, (2)Peking university, Beijing, China, (3)Peking University, Beijing, China