Early cretaceous magmatism during extensional deformation within the Antarctic Peninsula Magmatic Arc
- 作者：Vaughan ; Alan P.M. ; Millar ; Ian L.
- 刊名：Journal of South American Earth Sciences
- 出版年：1996
- 期刊代码：50_08959811
- 类别：ear
- 出版时间：January 3, 1996
- 卷：9
- 期：1-2
- 页码：121-129
- 文件大小：1.40 M
摘要
Early Cretaceous plutonic rocks at Creswick Peaks in NW Palmer Land, Antarctic Peninsula show evidence of synmagmatic crustal extension and deformation during emplacement and cooling at 141 ± 2 Ma. Deformation textures, ranging from sub-magmatic phenocryst alignment to ultramylonite, are preserved in granodiorite. Large volumes of gabbro were intruded late in the kinematic history. Crustal extension compensated by magma emplacement has occurred, and a close correspondence of ages between the shear zone, granodiorite and gabbro suggests a rapid phase of crustal growth. Extensional structures are partially overprinted by mid-Cretaceous thrusting and compression.