Abstract
In North Chile, Jurassic-Cretaceous arc magmatism is represented by several narrow belts of plutons and two separate volcanic sequences. New $^{40}Ar/^{39}Ar$ mineral ages confirm five distinct episodes of magma emplacement as plutonic complexes (c. 202-188 Ma, c. 160-153 Ma, c. 142-138 Ma, c. 130-127 Ma, and c. 106-103 Ma). Conjugate dike sets were emplaced immediately before periods of plutonism, and each distinct episode of magmatism prior to c. 127 Ma was located successively eastward, inboard from the subduction boundary, features interpreted to result from regional extension within the magmatic arc. Steeply dipping, ductile mylonitic shear zones were developed in wall-rocks along western contacts of Late Jurassic and Early Cretaceous plutons. Steeply-plunging mineral stretching lineations and a variety of kinematic indicators record an east-side-down extension. Along eastern faults of the Atacama Fault System steeply dipping, ductile mylonitic shear zones display subhorizontal mineral stretching lin...
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.