Imperial College London
Alternate

ProfessorJoannaMorgan

Faculty of Engineering, Department of Earth Science & Engineering

Emeritus Professor of Geophysics
 
 
 
//

Contact

 

+44 (0)20 7594 6423j.v.morgan

 
 
//

Location

 

1.46CRoyal School of MinesSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Zhao:2020:10.1016/j.gr.2019.12.003,
author = {Zhao, J and Xiao, L and Gulick, SPS and Morgan, JV and Kring, D and Fucugauchi, JU and Schmieder, M and de, Graaff SJ and Wittmann, A and Ross, CH and Claeys, P and Pickersgill, A and Kaskes, P and Goderis, S and Rasmussen, C and Vajda, V and Ferrière, L and Feignon, J and Chenot, E and Perez-Cruz, L and Sato, H and Yamaguchi, K},
doi = {10.1016/j.gr.2019.12.003},
journal = {Gondwana Research},
pages = {128--150},
title = {Geochemistry, geochronology and petrogenesis of Maya Block granitoids and dykes from the Chicxulub Impact Crater, Gulf of México: Implications for the assembly of Pangea},
url = {http://dx.doi.org/10.1016/j.gr.2019.12.003},
volume = {82},
year = {2020}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The Late Paleozoic tectono–magmatic history and basement of the Maya block are poorly understood due to the lack of exposures of coeval magmatic rocks in the region. Recently, IODP–ICDP Expedition 364 recovered drill core samples at borehole M0077A from the peak ring of the Chicxulub impact crater, offshore of the Yucatán peninsula in the Gulf of México, have been studied comprehensively. In the lowermost ~600 m of the drill core, impact–deformed granitoids, and minor felsite and dolerite dykes are intercalated with impact melts and breccias. Zircon U-Pb dating of granitoids yielded ages of around 326 ± 5 Ma, representing the first recovery of Late Paleozoic magmatic rocks from the Maya block, which could be genetically related to the convergence of Laurentia and Gondwana. The granitoids show the features of high K2O/Na2O, LaN/YbN and Sr/Y ratios, but very low Yb and Y contents, indicating an adakitic affinity. They are also characterized by slightly positive Nd(326Ma) of 0.17–0.68, intermediate initial 87Sr/86Sr(326Ma) of 0.7036–0.7047 and two–stage Nd model age (TDM2) of 1027–1069 Ma, which may indicate a less evolved crustal source. Thus, the adakitic granitoids were probably generated by partial melting of thickened crust, with source components similar to Neoproterozoic metagabbro in the Carolina block (Pan–African Orogeny materials) along Peri–Gondwana. Felsite dykes are shoshonitic with typical continental arc features that are sourced from a metasomatic mantle wedge by slab–fluids. Dolerite dykes display OIB–type features such as positive Nb and Ta anomalies and low ThNpm/NbNpm. In our interpretation, the Chicxulub adakitic granitoids of this study are formed by crustal anatexis due to asthenospheric upwelling resulting from slab breakoff. Through comparing sources and processes of Late Paleozoic magmatism along the Peri–Gondwanan realm, a tearing slab breakoff mode
AU  - Zhao,J
AU  - Xiao,L
AU  - Gulick,SPS
AU  - Morgan,JV
AU  - Kring,D
AU  - Fucugauchi,JU
AU  - Schmieder,M
AU  - de,Graaff SJ
AU  - Wittmann,A
AU  - Ross,CH
AU  - Claeys,P
AU  - Pickersgill,A
AU  - Kaskes,P
AU  - Goderis,S
AU  - Rasmussen,C
AU  - Vajda,V
AU  - Ferrière,L
AU  - Feignon,J
AU  - Chenot,E
AU  - Perez-Cruz,L
AU  - Sato,H
AU  - Yamaguchi,K
DO  - 10.1016/j.gr.2019.12.003
EP  - 150
PY  - 2020///
SN  - 1342-937X
SP  - 128
TI  - Geochemistry, geochronology and petrogenesis of Maya Block granitoids and dykes from the Chicxulub Impact Crater, Gulf of México: Implications for the assembly of Pangea
T2  - Gondwana Research
UR  - http://dx.doi.org/10.1016/j.gr.2019.12.003
UR  - https://www.sciencedirect.com/science/article/pii/S1342937X2030006X?via%3Dihub
VL  - 82
ER  -
Download