Abstract
Large-scale volcanic rocks of the Lanqi Formation are developed in the Changheyingzi area, western. Liaoning Province. LA-ICPMS zircon U-Pb dating gives the Late Jurassic eruption age for andesitic breccia lava of the Lanqi. Formation as 159. 4 ±3. 4 Ma. In-situ zircon Hf analyses show that Lanqi Formation have 176Hf/177 Hf values of 0. 282098 to 0. 282789,εHf (t) values of-20. 4 to + 4.1, tDM(depleted mantle model age) of 0. 7-1. 6Ga and tcrust (average crustal model age) of 0. 9-2. 5Ga, respectively. Combining the published geochemical data of the volcanic rocks, especially their Sr-Nd isotopic compositions, we interpret the andesitic volcanic rocks as products mainly derived from the partial melting of Neoarchean basaltic rocks in the lower crust due to the basaltic magmas underplating in Mesozoic time.
| Translated title of the contribution | In-situ U-Pb dating and Hf isotopic analyses of zircons in the volcanic rock of the Lanqi Formation in the Beipiao area, western Liaoning Province |
|---|---|
| Original language | Chinese |
| Pages (from-to) | 3287-3297 |
| Number of pages | 11 |
| Journal | Acta Petrologica Sinica |
| Volume | 25 |
| Issue number | 12 |
| Publication status | Published - 2009 |
| Externally published | Yes |
Keywords
- Lanqi Formation
- Late Jurassic
- Partial melting of lower crust
- Underplating
- Western Liaoning Province
- Zircon Hf istopes
- Zircon U-Pb age