Exhumation Processes of UHP Metamorphic Belt in the Northern Qaidam and Their Constraints to Rutile Mineralization: Evidences from Compositional Zoning of Garnets in Yuqia and West Tieshiguan Areas(PDF)
《地球科学与环境学报》[ISSN:1672-6561/CN:61-1423/P]
- Issue:
- 2016年第02期
- Page:
- 143-159
- Research Field:
- 基础地质与矿产地质
- Publishing date:
Info
- Title:
- Exhumation Processes of UHP Metamorphic Belt in the Northern Qaidam and Their Constraints to Rutile Mineralization: Evidences from Compositional Zoning of Garnets in Yuqia and West Tieshiguan Areas
- Author(s):
- CHEN Xin; ZHENG You-ye; XU Rong-ke; GUO Xian-zheng; WANG Hui-min; CAI Peng-jie; DU Wen-yang; LIN Cheng-gui; FANG Chang-tan; LU Rui; FAN Xian-bin
- 1. Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, Hubei, China; 2. Institute of Geological Survey, China University of Geosciences, Wuhan 430074, Hubei, China; 3. College of Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China
- Keywords:
- garnet; major element; trace element; rutile deposit; eclogite; UHP metamorphic belt; Qaidam Basin
- PACS:
- P588.3
- DOI:
- -
- Abstract:
- The ore-forming prospect of eclogite-type rutile in Yuqia is different from that in West Tieshiguan, located in the northern Qaidam ultrahigh-pressure(UHP) metamorphic belt. Recently, the large eclogite-type rutile ore deposit in Yuqia is found, but only titanium mineralization in West Tieshiguan is found. Based on detailed field geological and microscopic observation, the major elements were analyzed by electron probe; moreover, the in-situ trace element contents in garnet collected from the deposits were performed by LA-ICP-MS. The results show that the occurrences of Yuqia and West Tieshiguan eclogites are basically identical. Yuqia eclogite degenerates weakly with mineral idiomorphic granular, and garnets contain more inclusions. Major and trace earth elements have well-developed zoning characteristic, and the mantle and rim enrich rare earth element in garnets. Relatively, the degeneration of West Tieshiguan eclogite is strong and mineral xenomorphic-granular. Some garnets of eclogites contain less inclusions and the zoning of major element has been homogenized, rare earth elements of the core and mantle are more than the side. Combining the chronology evidences, Yuqia eclogite undergoes rapid subduction and exhumation of the dynamic process, and the rutiles barely turn into ilmenites. West Tieshiguan eclogite undergoes an evolution history with a rapid burial and slow uplift, and the rutiles nearly turn into ilmenites, which reveal the differences between the dynamics process and the occurrence state of rutile. These characters provide directions for the study area to further find eclogite-type rutile deposits in the northern Qaidam UHP metamorphic belt.
Last Update: 2016-03-28