Table 1.

Summary of Late Cenozoic crustal thickening and uplift for the northern Bolivian Andes (with 2σ error bars), calculated in 2D crustal balancing reference model (γ = 1)

Location and deformation phaseBrittle crustal thickening* (km)Ductile crustal thickening* (km)Total crustal thickening* (km)Surface uplift (km) (k = 6.5 ± 1)Rock uplift proxy† (km)
Altiplano, uniform ductile crustal flow
6–0 Ma (γ2 = 1)0.3 ± 0.35.1 ± 1.75.4 ± 1.80.84 ± 0.30.6 ± 1.0 (QG)
10–6 Ma (γ1 = 1)3.3 ± 1.75.0 ± 1.08.3 ± 2.01.3 ± 0.42.5 ± 1.0 (QG)
10–0 Ma3.6 ± 1.710.1 ± 2.113.7 ± 2.82.14 ± 0.5<3.3 (QG), 2.8 ± 0.5 (G)
Eastern Cordillera, uniform ductile crustal flow
6–0 Ma (γ2 = 1)5.1 ± 1.75.1 ± 1.70.83 ± 0.3
10–6 Ma (γ1 = 1)5.0 ± 1.05.0 ± 1.70.8 ± 0.2
10–0 Ma10.1 ± 2.110.1 ± 2.11.63 ± 0.41.75 ± 0.7 (1.5 ± 0.7) (BL)
  • γ, focusing factor (see text); k, isostatic compensation factor, where uplift = 1/k × crustal thickening.

  • *Parameters used: present width of Corque–Corocoro basin, 120 ± 30 km; present width of zone of ductile crustal flow, 250 ± 20 km; shortening in Corque–Corocoro structure: 10–6 Ma, 26 ± 5 km, and 6–0 Ma, 2 ± 2 km; underthrusting of Brazilian Shield: 10–6 Ma, 25 ± 5 km, and 6–0 Ma, 45 ± 10 km; thickness at depth of incoming Brazilian shield (piston thickness), 27 ± 5 km; average crustal thickness today beneath high Andes, 60 ± 2 km; thickness of brittle layer 15 ± 5 km.

  • †Sources for estimates: QG, Ghosh et al. (2006), Quade et al. (2007) and Garzione et al. (2008); G, Gregory-Wodzicki et al. (1998); BL, Barke & Lamb (2006). Surface uplift is given in parentheses, assuming erosion is 230 ± 90 m (Barke & Lamb 2006). See kinematic constraints on the focusing factor γ and Figs 8 and 9 for solutions with γ ≠ 1.