Tectonics of Unusual Crustal Accretion in the Parece Vela Basin - Accretionary Prisms and Convergent Margin Tectonics in the Northwest Pacific Basin - page 152

b

21˚N

S7

50 km

S6

20˚N

6B

6A

S5

6C

S4

19˚N

7

S3

6 A

18˚N

6B

S2

17˚N

S1

16˚N

6A

Chaotic
Terrain

15˚N

135˚E 136˚E 137˚E 138˚E 139˚E 140˚E

Bathymetry (m)

−10000 −8000 −6000 −4000 −2000 0

Fig. 1 (continued)

footwalls of low-angle detachment faults (Cann et al. 1997 ; Blackman et al. 1998 ;
Tucholke et al. 1998 ; Escartín et al. 2003 ; MacLeod et al. 2009 ).
Normal faults are expected to develop increasing offset with increasing tectonic
extension. Many earlier models of OCC formation (e.g., Tucholke et al. 1998 ;
Blackman et al. 1998 ; Escartín et al. 2003 ) considered that amagmatic extension
along a given section of ridge segment was important for long-lived detachment
faulting. However, recent studies instead suggest that magmatic supply is the key