Strong lateral strength contrasts in the mantle lithosphere of continents: A case study from the hot SW Canadian Cordillera

摘要: Abstract This study aims at quantifying the 3-D variability in lithosphere strength of south-eastern Canadian Cordillera and adjacent craton to east. Strength is calculated a forward manner, starting from rheological laws brittle ductile deformation. The work flow calculates temperature model based on multi-layer compositional subsequently estimates distribution both models. modeling involves numerical inversion cubic spline algorithms which enable impose boundary conditions that account better for strong lateral variations thickness heat flow. addresses structure between craton. marked by hot thin ~ 60 km stands contrast cold thick ~ 170 km east, consequently results pronounced changes bulk strength. high surface interior its with Foreland Basin can be reproduced models combine elevated mantle due higher crustal production magmatic intrusions. A series models, examines role different input composition strain rate, shows first-order pattern persistent. For Cordillera, resides > 80% upper crust integrated 2.0–3.5⋅106 MPa⋅m. craton, provides > 75% values 4.0–8.0⋅106 MPa⋅m 20–65⋅106 MPa⋅m lithosphere. Effective elastic estimated 5 15 km 40–80 km illustrates transition as prominent feature dynamics spatial seismicity trends.