Flat slab subduction dynamics in a mantle reference frame: Examples from the Andes , Mexico , and Tibet
Douwe J.J. van Hinsbergen, Lydian M. Boschman, Wim Spakman
Schepers, G., van Hinsbergen, D.J.J., Spakman, W., Kosters, M.E., Boschman, L.M., McQuarrie, N., 2017, South American plate
advance and forced trench retreat as drivers for transient Andean flat subduction episodes, Nature Communications 8, 15249 Boschman, L.M., van Hinsbergen, D.J.J., Kimbrough, D.L., Langereis, C.G., and Spakman, W., 2018, 220 Myr of Farallon
Plate subduction below Mexico, Geochemistry, Geophysics, Geosystems, accepted pending revision van Hinsbergen, D.J.J., Lippert, P.C., Li., S., Huang, W., Advokaat, E.L., and Spakman, W., 2018, Reconstructing Greater India:
paleogeographic, kinematic, and geodynamic perspectives, Tectonophysics in press
D
Vizcaino fore-arc basin NAM FAR
Arperos back-arc basin
?
500 km
Lower mantle and crustal deformation vertically not to scale
660 km 220 Ma
200 Ma
160 Ma
115 Ma
40 Ma
0 Ma
Basin and Range
Laramide fold thrust belt
A
B
G
C D
E F
Snapshot: Interval:
Arperos lithosphere
60 Ma flat slab
T
slab wall
slab wall
FAR M
NAM SB,T
FAR M
NAM, SB, T
FAR M, NAM, SB, T
FAR M
NAM SB,T
FAR M
NAM SB, T
FAR M, SB
NAM
FAR NAM M
SB
roll-back overriding plate advance
subduction rate
SB
T
T
overriding plate shortening overriding plate extension
M stationary reference
flat slab formation
flat slab steepening
? - 220 Ma
roll-back = trench advance > overriding plate advance:
overriding plate extension (Vizcaino fore-arc spreading)
160 - 115 Ma
roll-back = trench advance > overriding plate advance:
overriding plate extension (Arperos Basin opening)
40 - 0 Ma
roll-back = trench advance > overriding plate advance:
overriding plate extension (Basin and Range extension) 60 - 40 Ma
roll-back > overriding plate advance > trench advance:
overriding plate shortening and slab steepening (Laramide shortening)
200 -160 Ma
- stationary overriding plate
- stationary trench and slab bend:
slab wall formation 220 - 200 Ma
roll-back = trench advance = overriding plate advance
115 - 60 Ma
- mantle stationary slab bend:
slab wall formation
- overriding plate advancing > trench advance > roll-back:
overriding plate shortening and flat slab formation (Arperos closure and Laramide shortening)
D
D
B D
D
Lhasa Xigaze forearc
Neotethys Ocean Tibetan/Greater Himalayan
microcontinent Greater India Basin
India
>58 Ma A
Cretaceous oceanic crust Jurassic and olderoceanicc rust
660 km upper mantle
lower mantle Rapid transfer of slab
to lower mantle
High subduction rates (>16 cm/yr)
old oceanic crust subduction (>90 Ma)
~58 Ma B
Accreted Tibetan/
Greater Himalaya Xigaze ophiolites
Rapid transfer of slab to lower mantle
High subduction rates (>16 cm/yr)
old oceanic crust sinking in upper mantle (>90 Ma)
660 km upper mantle lower mantle
~50 Ma C
Slow transfer of continental and young oceanic lithosphere to lower mantle
Sharp decrease in subduction rates (<8 cm/yr)
Young oceanic crust subduction (<40 Ma); buckling and clogging upper mantle
660 km upper mantle lower mantle
~40 Ma
660 km upper mantle
lower mantle
Tibetan plateau shortening
Slab pile tipping over northward generating flat slab subduction
Northward migration arc;
strong decrease arc volume
660 km upper mantle
lower mantle
Lesser Himalaya accretion
Overturned slab shearing off horizontally underthrusting Indian continental lithosphere
End of volcanism
~25-15 Ma LH
TH/GH
Gangdese volcanic arc
Linzizong ignimbrite flareup
Gangdese volcanic arc slab buckling
and/or thickening
slab buckling and/or thickening
In
Hi
underthrusted Indian continental
lithosphere
Indian continent
M,B,T O
m
bo mo
ko
LH
GH TH XF
Entirely subdu cted G
reater India
C
58 Ma
Africa/
Arabia
India
Eurasia
Australia
30°N
0°N
Paleomagnetic Reference Frame
bo mo
ko
A
India
Africa
Arabia
Eurasia
Burma
0 Ma
30°N
Paleomagnetic Reference Frame
m
k
B
Africa/
Arabia
30 Ma
Eurasia
India
30°N
Paleomagnetic Reference Frame
m
k
PPE
PPE
WA WA
M,B,T O
M, T
O B
M
O T
M
O T
overriding plate
contraction
{ {
trench retreat=
slab rollbacksubduction rate
{
O T,B M D
slab overriding
plate
contraction
{ { {
trench retreatrollbackslab{
O T B M D
O D
M T
B
Mode 1: Trench retreat = slab rollback rate: dipping slab
B T
O D
M
B T
O D
M
O D
M T D B
Mantle frame
0°
30° S
50 Ma
50 Ma Absolute motion
trench
Absolute motion trench
Absolute motion South America 0 Ma
0 Ma 50 Ma 0 Ma
Trench at 50 Ma
~1000 km subduction
50 Ma 12 Ma
Present trench
A B
Present location slab
~1000 km
~250 km
Subduction thrice as much as Dipping slab: ~1000 km roll-back Flat slab: ~750 km roll-back
Not
reconstru cted
100 km depth contour
t = 0 t = 1 t = 0 t = 2 t = 0 t = 3 t = 0
1. forced trench retreat;
slab roll-back 2. roll-back resistance; tearing, 4. tear subduction, process repetition
Trigger mechanism
overpressuring of
sub-slab mantle; sub-slab pressure release;
Trigger mechanism overpressured
sub-slab mantle 10 20 30
40 50
10 20 30
40 50
550 km
~180 km 150 km
O’Neill et al. 2005 Doubrovine et al. 2012 Torsvik et al. 2012
05
~1100 km
Present-day trench
~900 km
Trench at 50 Ma
A B
90°W 60°W
60°S 30°S
60°W 50°W 40°W
70°W 80°W
40°S 30°S 20°W 10°W
