Upwelling Process of the Western Himalaya Mountains: Height and Velocity Estimation Evidenced by Formation and Evolution of the Zanda Basin,Tibet,China

Based on field geological survey, stratigraphic section measurement and indoor comprehensive investigation, the Zanda Basin's tectonic location in the Himalaya Plate was ascertained, and the formation and evolution of the Zanda Basin during the Pliocene to Early Pleistocene was classified as six stages: (a) primary rift‐faulting stage, (b) quick rift‐faulting Stage, (c) intensive rift‐faulting stage, (d) stasis stage, (e) secondary rift‐faulting stage, and (f) secondary quick rift‐faulting stage. Based on this six‐staged formation‐evolution theory of the Zanda Basin, the upwelling process of the Western Himalaya Mountains from the Pliocene to Early Pleistocene was classified as the following five stages: (a) slow upwelling stage (5.4–4.4 Ma), (b) mid‐velocity upwelling stage (4.4–3.5 Ma), (c) quick upwelling stage (3.5–3.2 Ma), (d) upwelling‐ceasing stage (3.2–2.7 Ma), and (e) quick upwelling stage (2.7 Ma). Research has shown that in the duration from the Early Pliocene (4.7 Ma) to the End of Pliocene (2.67 Ma), which lasted 2.03 million years, the Himalaya Mountains had uplifted 1500 m at a velocity of 0.74 mm/a; this belongs to a mid‐velocity upwelling. During the 1.31 million years in the Early Stage of the Early Pleistocene, the Himalaya Mountains had risen up another 1500 m at a velocity of 1.15 mm/a; this is a rather quick upwelling. All of these data have shown that the upwelling of the Western Himalaya Mountains is along a complicated process with multi‐stages, multi‐velocities, and non‐uniformitarian features.