Thermal structure and evolution of an Archean large hot orogen: Insights from the Tasiusarsuaq terrane, SW Greenland
Thermal structure and evolution of an Archean large hot orogen: Insights from the Tasiusarsuaq terrane, SW Greenland
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太古代大型热造山带的热结构和演化：来自格陵兰岛西南部 Tasiusarsuaq 地体的见解
DOI：
10.1016/j.precamres.2019.105499
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发表时间：
2019
影响因子：
3.8
通讯作者：
Scherstén
中科院分区：
文献类型：
--
作者：
Dziggel;Diener;Kokfelt;Scherstén
Tasiusarsuaq地体代表了一个太古宙大陆上板块，在大约2970年至2700 Ma之间，一系列火成岩和构造事件组装并加厚了该板块。对现有数据的审查结合热力学模拟和钛铁矿和锆石U-铅测年，可以详细了解中太古代和新太古代期间的地壳生长过程。在弧形背景下，大约2970-2950 Ma Fiskenæsset杂岩侵入之后，Tasiusarsuaq地体的南部在大约2920到2880 Ma之间被早期的TTG代侵入，形成了比约纳斯德地块。随后，在约2880~2830 Ma期间，Ttg岩浆活动迁移至塔苏萨尔苏克地体中部和北部的Sermilik地块，而二长花岗岩岩浆活动则发生在南部。我们将这种火成岩活动模式解释为Sermilik地块向Bjørnerund地块的吸积，以及在吸积的地体后面形成新的板块界面的结果。与这一早期增长阶段有关的组构保存在来自比约内蒙德地块的前进型角闪岩相(580-630 °C；4-6 kbar)岩性中，其钛铁矿U-Pb年龄为约2820 Ma。此后，持续的南向俯冲导致大量增厚，表现为高压麻粒岩相变质作用(870 °C，9.0-9.2 kbar)和c.2805-2785 Ma Ilivertalik侵入杂岩的侵入。早太古代陆壳(Færingehavn地体)在约2760-2720 Ma期间的会聚和俯冲导致了热的韧性麻粒岩推覆体向中地壳的挤压。当时，Tasiusarsuaq地体的大段进行了广泛的角闪岩相改造，条件从中部的~725 °C到5.00-5.5 Kbar，到北部的6.5-7 Kbar和700 °C。这些条件一直持续到2720-2700 Ma的地体最后碰撞。总的来说，我们的模型描述了太古宙大型热造山带的演化，其特征是连续的会聚而不是间歇性的俯冲。在许多方面，它类似于较新的大型热造山带，如格伦维尔，包括碰撞造山之前地体的吸积。
The Tasiusarsuaq terrane represents an Archean continental upper plate that was assembled and thickened by a series of igneous and tectonic events between c. 2970 and 2700 Ma. A review of the available data combined with thermodynamic modelling and U-Pb titanite and zircon dating allows detailed insight into the processes of crustal growth during the Meso- and Neoarchean. Following the intrusion of the c. 2970–2950 Ma Fiskenæsset complex in an arc-type setting, the southern part of the Tasiusarsuaq terrane was intruded by an early TTG generation between c. 2920 and 2880 Ma to create the Bjørnesund block. Subsequently, from c. 2880 to 2830 Ma, TTG magmatism migrated to the Sermilik block in the central and northern part of the Tasiusarsuaq terrane, whereas monzogranite magmatism occurred in the south. We interpret this pattern of igneous activity to be a result of accretion of the Sermilik block to the Bjørnesund block and the formation of a new plate interface behind the accreted terrane. Fabrics related to this early accretionary stage are preserved in the prograde amphibolite facies (580–630 °C; 4–6 kbar) lithologies from the Bjørnesund block that have U-Pb titanite ages of c. 2820 Ma. Afterwards, ongoing southwards-directed subduction led to substantial thickening, manifested by high-pressure granulite facies metamorphism (870 °C, 9.0–9.2 kbar) and the intrusion of the c. 2805–2785 Ma Ilivertalik intrusive complex. Convergence and underthrusting by Eoarchean continental crust (Færingehavn terrane) at c. 2760 to 2720 Ma led to the extrusion of hot, ductile granulite nappes into the mid crust. At this time, large sections of the Tasiusarsuaq terrane underwent extensive amphibolite facies reworking, at conditions ranging from ~725 °C to 5.0–5.5 kbar in the central parts to 6.5–7 kbar and 700 °C in the north. These conditions lasted until the final collision of the terranes at 2720–2700 Ma. Collectively, our model describes the evolution of an Archean large hot orogen that is characterized by continuous convergence rather than intermittent subduction. In many respects, it resembles more recent large hot orogens such as the Grenville, including the accretion of terranes prior to collisional orogeny.
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影响因子：
3.8
作者：
C. Friend;A. Nutman
通讯作者：
C. Friend;A. Nutman
格伦维尔造山带的构造环境和演化：过去 40 年进展评估
DOI：
--
发表时间：
2015
期刊：
影响因子：
--
作者：
T. Rivers
通讯作者：
T. Rivers
影响因子：
1.4
作者：
C. Beaumont;R. Jamieson;M. Nguyen
通讯作者：
C. Beaumont;R. Jamieson;M. Nguyen
影响因子：
3.4
作者：
L. Riciputi;J. Valley;V. R. Mcgregor
通讯作者：
L. Riciputi;J. Valley;V. R. Mcgregor
影响因子：
64.8
作者：
T. Næraa;A. Schersten;M. Rosing;A. Kemp;J. Hoffmann;T. Kokfelt;M. Whitehouse
通讯作者：
T. Næraa;A. Schersten;M. Rosing;A. Kemp;J. Hoffmann;T. Kokfelt;M. Whitehouse