Crustal evolution events in the Chinese continent: evidence from a zircon U-Pb database

Abstract

The zircon U-Pb chronology database provides a good opportunity to obtain important zircon growth peak periods in the Earth's history so as to study the origin and evolution of the crust. It should be noted that research preference affects the objectivity of zircon sampling, leading to hot data in the database and age statistics. To evaluate the influence of hot data on statistical results, the W and Y indexes are introduced. Using a Gaussian model of multipeak fitting of zircon U-Pb age frequencies, we identify seven major growth peaks in zircons from the Chinese continental crust, which are 2498.95, 1855.82, 828.88, 444.29, 249.46, 131.96, and 58.21 Ma. Due to differences in the time scales of zircon growth peaks, these peaks can be divided into two categories: first-order zircon growth peaks (I) and second-order zircon growth peaks (II), which represent longer and shorter time scales, perhaps due to different kinds of geological dynamics, respectively. In addition, there are clear correspondences between these ages and various geological events recognized by most scholars, namely, the Wutai orogeny, Lvliang orogeny, Jinning orogeny, Caledonian orogeny, Indosinian orogeny, Yanshanian orogeny, and Himalayan orogeny, respectively.

Keywords

• crustal evolution
• major geological event
• time scale
• zircon u-pb chronology database
• hot data