학술논문

Fault-mediated melt ascent in a Neoproterozoic continental flood basalt province, the Franklin Sills, Victoria Island, Canada
Document Type
Academic Journal
Source
Geological Society of America Bulletin. 124(5-6):723-736
Subject
05A|Petrology - igneous and metamorphic rocks
16|Structural geology
Arctic Archipelago
basalts
Canada
contact metamorphism
dikes
emplacement
faults
flood basalts
Franklin Sills
igneous rocks
intrusions
large igneous provinces
magma chambers
magma transport
magmas
metamorphism
Neoproterozoic
Northwest Territories
Nunavut
periodicity
Precambrian
Proterozoic
sills
structural controls
transport
upper Precambrian
Victoria Island
volcanic rocks
Western Canada
Language
English
ISSN
0016-7606
Abstract
The Neoproterozoic Franklin large igneous province on Victoria Island, Canada, is characterized by continental flood basalts and a sill-dominated feeder system. Field relationships indicate that fault-guided transfer zones allowed magma to jump up-section to form higher-level intrusions. Where sills connect to dikes and magmas moved up-section, roof and wall rocks are characterized by wide and intense contact-metamorphic haloes, consistent with throughflow of magma. The geometric constraints suggest that conduits may have opened episodically and then closed when magma pressure waned. The episodic nature of conduit opening events can explain the pulsed ascent of crystal slurries, and may also play a role in the deposition of Ni-sulfides.