查詢結果分析
來源資料
相關文獻
- Thermochronological Study of the Dabie Shan Ultrahigh-Pressure Metamorphic Terrane, East Central China
- 中國東部大別山造山帶熱定年學研究及其在構造演化之意義
- 40Ar/39 Geochronology of Volcanic and Intrusive Rocks in the Dabie and Sulu Terranes, Eastern China, and Their Tectonic Implications
- Role of the Nanjih Fault on the Exhumation of the Pingtan-Dongshan Metamorphic Belt, Se China
- 40Ar/39Ar Dating of Mylonitization in the Tananao Schist, Eastern Taiwan
- Field Occurrence, 40Ar/39Ar Dating and Petrochemical Features of Volcanic Rocks in Mienhuayu off NE Taiwan
- 40Ar/39Ar Dating of High-Pressure Rocks in the Tananao Basement Complex, Taiwan
- 40Ar/39Ar Method of K-Ar Age Determination of Geological Samples Using Tsing-Hua Open-Pool (THOR) Reactor
- 40Ar/39Ar Dating of Plutonic/Metamorphic Rocks from Chinmen Island off Southeast China and Its Tectonic Implications
- Diversity and origin of quaternary basaltic magma series in northern Taiwan
頁籤選單縮合
題 名 | Thermochronological Study of the Dabie Shan Ultrahigh-Pressure Metamorphic Terrane, East Central China=大別山超高壓變質帶之定年學研究 |
---|---|
作 者 | 劉瑩三; 羅清華; 蔡金河; 王珮玲; 陳正宏; | 書刊名 | 中國地質學會會刊 |
卷 期 | 42:2 1999.05[民88.05] |
頁 次 | 頁159-188 |
分類號 | 356.2 |
關鍵詞 | 定年學; 超高壓變質帶; 大別山; Thermochronology; Ultra-high pressure metamorphism; Dabie Shan; |
語 文 | 英文(English) |
中文摘要 | 大別山超高壓變質帶內礦物之□Ar/□Ar年代,顯示此一超高壓帶曾於中生代抬升 過程當中,以三階段方式冷卻。首先於241~190Ma間,以5.6~17.7℃/Ma之速度發生快速冷 卻,然後冷卻速度於190~140Ma間,有明顯減緩的趨勢(1.3~2.7℃/Ma),績以於140~100Ma 間再次發生快速冷卻(5.0~9.8℃/Ma)。此種冷卻趨勢雖不見得顯示三階段之抬升作用,但由 變質岩發生再次快速冷卻之年代與變質帶內發現同時代之鐵鎂質岩脈(130-100Ma)看來,超高 壓變質帶的抬升作用,應與中國東部晚中生代之岩石圈張裂作用有關。此外,大別山超高壓 變質帶雖曾被推測具有四個岩石單元,這些單元分別代表揚子-中朝陸塊縫合帶內的四個構造 單元,於陸陸碰撞縫合過程中,扮演不同之構造運動角色。但本研究工作結果顯示,四個單 元的冷卻歷史並無明顯的時間差異,此一現象似乎更支持上述超高壓變質帶的晚期抬升作 用,係與岩石圈張裂作用有關的推論。 |
英文摘要 | □Ar/□Ar thermochronological data for hornblende, white micas, biotite, and K-feldspar from gneissic rocks, indicate a three-stage cooling history (~241 to 100Ma) for the exhumation of the Dabie Shan ultrahigh-pressure (UHP) metamorphic terrane in east central China. From middle Triassic to early Cretaceous, the Dabie terrane has experienced a rapid cooling (5.6-17.7℃/Ma) in the period of 241-190Ma, a relatively slow cooling (1.3-2.7℃/Ma) at 190-140Ma, and another fast cooling (5.0-9.8℃/Ma) during 140-100Ma. Despite of apparent differences of lithological assemblages among the four units within the Dabie terrane, no significant variation in cooling history can be found among them. This finding implies that the whole terrane may have exhumed as a single tectonic block. This is significantly different from what was expected from previous tectonic models, which may therefore need further evaluation. Mafic dykes collected from the terrane yield Cretaceous ages in the range of 133-100Ma, indicating that there was a regional magmatic activity during Jurassic-Cretaceous. On the basis of previously published data and our new thermochronological data, it becomes more evident that a large-scale post-collisional extension may have played an important role in the exhumation of the Dabie UHP terrane. |
本系統中英文摘要資訊取自各篇刊載內容。