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60°E E
80°N
80°N
60°N 60°N 60°N Seward 70°N 70°N 70°N 180° 80 N 150°E 120°E 120°E 120°E 90°E 90°E 90°E 60°E
60
180°
180°
Peninsula
150°E
150°E
Podvodnikov
Basin
Southwestern
Southwestern Paleogene
Southwestern
subterranes
subterranes
subterranes fault
Farewell Brooks Amerasian Basin Lomonosov Gakkel
Farewel
Farewelll
Makarov Paleozoic
fault
Aleutian
Basin
Chukchi Borderland
150°W
150°WW
30°E
30°E
150° Denali Kaltag Canada Ridge 30°E
Eurasian Basin
Ridge
area of inferred
Range
Trench
North Slope
North Slope
North Slope South Amerasia Basin oceanic crust Alpha 30°W Svalbard
Ridge
subterrane
subterrane
Yukon-Tanana north
Yukon-Tanana north
Alaska Yukon subterrane Ridge Harder Fjord de Geer
Canadian Arctic Transform System
Canadian Arctic Transform System
Porcupine
Pacific Canadian Arctic Transform System
St Elia Yukon-Tanana north Tuk Pearya
St Elias
St Eliass
Pearya
Pearya
Ocean Prince Patrick Atlantic
Island
Yukon-Tanana south
Yukon-Tanana south
Yukon-Tanana south
Alexander
Alexander
Island
Prince of
Prince of
Prince of Charlotte NWT NWT NWT Banks Sverdrup Franklinian Ocean 0°
basin
0°
0°
Wales
Walesles
Wa Alexander BC Tintina Devonian Basin Caledonian Germania Land
Ellesmere
Ellesmere
Mackenzie
Mackenzie
Queen 1 Mackenzie Mtns Mtns Mtns 2 Nunavut clastic wedge Ellesmere deformation zone
Caledonian
Caledonian
Island
Island
Island
Bank
Bankss
Banks 90°W Greenland deformation Storstrømmen
deformation front
120°W
deformation front
120°W
Island
Island
Island 120°W shear zone
Cordilleran
Cordilleran
Cordilleran Arctic Alaska terrane
deformation
deformation
Baffin
0 500 deformation front pole of Insular-Arctic terranes
Bay
70°N
70°N
km rotation 60°W 60°W 60°W 70°N front
front
front
Figure 1. Generalized terrane map showing the location of the Canadian Arctic transform system, geophysically defined features in the Canada Basin, and
terrane distribution on the Arctic and Cordilleran margins of Laurentia (modified after Colpron et al., 2019). Insets show simplified (1) rotation and (2) trans-
lation models (from Patrick and McClelland, 1995).
2019). The North Slope subterrane was incor- Structures that accommodated translation the Porcupine shear zone while it was an
porated into the greater Arctic Alaska terrane of Pearya project eastward to faults with active lithosphere-scale transform (Ward et
and juxtaposed with the Laurentian margin similar timing and kinematics in Svalbard al., 2019). Strike-slip basin sedimentation
by the Carboniferous (Strauss et al., 2013). (Fig. 1; Mazur et al., 2009). Although com- may be recorded by the newly recognized
South-directed Late Devonian–Carboniferous monly linked with strike-slip faults in the Devonian–Carboniferous Darcy Creek for-
structures on the north side of this boundary Caledonides (e.g., Storstrømmen shear zone; mation within the Porcupine shear zone
mark the probable offset western continuation Fig. 1), we suggest that faults in Svalbard (Faehnrich et al., 2021).
of the Ellesmerian orogen (Oldow et al., 1987). truncate the Caledonian structures and con- Linking strike-slip structures across
tinue eastward to Scandinavia as the de Geer Svalbard and northern Ellesmere Island to
PALEOZOIC TERRANE ACCRETION transform (Fig. 1; Lundin and Doré, 2019). Yukon and Alaska on the basis of orienta-
AND TRANSLATION ON THE PEARYA The Harder Fjord fault zone, a long-lived tion, timing, and kinematics defines a
AND PORCUPINE SHEAR ZONES steep structure that juxtaposes Ediacaran arc throughgoing Paleozoic fault system on the
Models that invoke terrane translation from rocks with the Franklinian margin on North northern Laurentian margin (Fig. 1), referred
the Arctic domain to the Cordilleran margin Greenland (Rosa et al., 2016), is similar to to here as the Canadian Arctic margin
(e.g., Northwest Passage model; Colpron and faults in Pearya and Svalbard (Fig. 1). transform system (CATS). Recognition of
Nelson, 2009) require a transcurrent bound- Strike-slip faults project westward from CATS carries significant implications for
ary along the Paleozoic Arctic margin. Pearya to the boundary between the Paleozoic paleogeographic reconstructions
Evidence for such a boundary on Ellesmere Laurentian margin and North Slope subter- of the northern Laurentian margin. Dis-
Island was outlined by Trettin (1998) in his rane in Yukon (Fig. 1). This boundary is placement and terrane juxtaposition along
assessment of the history of Pearya. Recent marked by the Porcupine shear zone, a broad the margin culminated with south-directed
fieldwork has confirmed that Pearya is sepa- fault zone (>17 km wide) of older sinistral shortening of the Late Devonian–Early
rated from the Laurentian margin by vertical and recent (late Cenozoic) dextral brittle Carboniferous Ellesmerian orogeny and
strike-slip structures that record a complex deformation (von Gosen et al., 2019). The development of a thick clastic wedge derived
history of reactivation, overprinting, and lithology and structural history of the North from a continental sediment source to the
reversals in displacement direction (Piepjohn Slope subterrane contrast sharply with the north. The nature of this northern source
et al., 2015). Current timing estimates for adjacent Laurentian margin rocks and are remains tentative but is most probably
Paleozoic sinistral displacement suggest a more akin to units in northeastern Laurentia derived from the Arctic Alaska–Chukotka
long-lived Ordovician to Devonian metamor- (Macdonald et al., 2009; Strauss et al., 2013; terrane (Beranek et al., 2010; Anfinson et
phic and deformation history associated with Gibson et al., 2021). Although originally al., 2012). The CATS model that accommo-
juxtaposition and translation of Pearya along interpreted to crosscut the shear zone (Lane, dates large-magnitude translational motion
the Laurentian margin (McClelland et al., 1992), Devonian granitoids common to the of terranes suggests the source may have
2012; Kośmińska et al., 2019). North Slope subterrane were emplaced within varied through time.
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