# name
Faults and lineaments of the Western Quebec Seismic Zone, Quebec and Ontario

# metadata.dc.description[].value
This Open File Report documents interpreted brittle lineaments and mapped faults of the Western Quebec Seismic Zone.

# metadata.dc.description[].value
Ce dossier public documente et interprète les lineaments et failles de la zone sismique de l,Ouest du Québec.

# metadata.dc.description.abstract[].value
This Open File contains the interpreted brittle lineaments and a compilation of mapped faults of an area bound by latitudes 44°N and 48°N and longitudes 73°W and 80°W. The area includes most of the Ottawa River watershed. It also covers most of eastern Ontario and theLaurentians, between Montréal (QC) and North Bay (ON). The study area includes the seismically active region known as the Western Quebec Seismic Zone (WQSZ). The WQSZ is an area where earthquakes as large as magnitude 6.2 have occurred in the past and where tens of smaller earthquakes are recordedyearly. Our study is an attempt to provide a homogeneous coverage of these brittle structures through an integration of visually interpreted lineaments and mapped faults. The possible relationships between these brittle faults and earthquakes will be examined later.Lineaments were observed mostly from the Digital Elevation Model (DEM) of the Canadian National Topographic Data Base (NTDB) at a scale of 1:250 000. The DEMs illuminated from two directions were used to first visually recognize lineaments and second, to georeference their surface expressions in aGeographic Information System (GIS). Since the final goal was to better map the brittle faults that could be reactivated in earthquakes, the clear ductile structures were not considered in this study and the more questionable ones re-evaluated subsequently against known geological information. Mostof the region of interest is southeast of the Grenville Front, where all ductile structures are related to the Grenville orogeny (about 1 billion years ago). The recognition of brittle structures is based on the observation that they are essentially linear in plan view. On the other hand, theductile structures are generally curved, enhance contact between different Grenvillian lithologies, or present a distinct structural pattern. With a few exceptions, only lineaments with a length greater than 5 km were included. After a first detection pass, lineaments at a more regional scale weredrawn by interpolating between segments of lineaments. These interpolated segments corresponded to areas where the topography was subdued and where no conspicuous trace existed. The interpreted lineaments were then compared with the provincial geological  maps of Quebec and Ontario, which often didnot distinguish between brittle faults and ductile shear zones. Lineaments that coincided with diabase dykes were recognized by consulting geological maps and by examining the total magnetic field. Our final product is a 1:750,000 scale map that can be used in the future to better understand theseismotectonics of this region.

# metadata.dc.relation.isrelatedto[].value
Faults and lineaments of the Quebec City, Charlevoix and Saguenay-Lac St-Jean regions, Québec

# metadata.dc.relation.isrelatedto[].value
Faults and lineaments of the Quebec City, Charlevoix and Saguenay-Lac St-Jean regions, Québec

# metadata.dc.subject.other[].value
Canadian National Topographic Data Base (NTDB)

# metadata.dc.title[].value
Faults and lineaments of the Western Quebec Seismic Zone, Quebec and Ontario