Disparate crustal thicknesses beneath oceanic transform faults and adjacent fracture zones revealed by gravity anomalies

Guo，Zhikui1,2; Liu，Sibiao2; Rüpke，Lars2; Grevemeyer，Ingo2; Morgan，Jason P.3; Lange，Dietrich2; Ren，Yu2; Tao，Chunhui1,4

2023

10.1130/G50429.1

Geology   Impact Factor & Quartile

0091-7613

1943-2682

Plate tectonics describes oceanic transform faults as conservative strike-slip boundaries, where lithosphere is neither created nor destroyed. Therefore, seafloor accreted at ridge-transform intersections should follow a similar subsidence trend with age as lithosphere that forms away from ridge-transform intersections. Yet, recent compilations of high-resolution bathymetry show that the seafloor is significantly deeper along transform faults than at the adjacent fracture zones. We present residual mantle Bouguer anomalies, a proxy for crustal thickness, for 11 transform fault systems across the full range of spreading rates. Our results indicate that the crust is thinner in the transform deformation zone than in either the adjacent fracture zones or the inside corner regions. Consequently, oceanic transform faulting appears not only to thin the transform valley crust but also leads to a secondary phase of magmatic addition at the transition to the passive fracture zones. These observations challenge the concept of transform faults being conservative plate boundaries

English

NI Journal Papers

Others

National Natural Science Foundation of China[42127807];

GEOSCIENCES

2-s2.0-85150849802

Scopus

1.Key Laboratory of Submarine Geosciences,Second Institute of Oceanography,MNR,Hangzhou,310012,China
2.GEOMAR,Helmholtz Centre for Ocean Research Kiel,Kiel,Wischhofstrasse 1-3,24148,Germany
3.Southern University of Science and Technology,Shenzhen,Xueyuan Avenue 1088,518055,China
4.School of Oceanography,Shanghai Jiao Tong University,Shanghai,1954 Huashan Road,200030,China

Guo，Zhikui,Liu，Sibiao,Rüpke，Lars,et al. Disparate crustal thicknesses beneath oceanic transform faults and adjacent fracture zones revealed by gravity anomalies[J]. Geology,2023,51(3):300-304.

Guo，Zhikui.,Liu，Sibiao.,Rüpke，Lars.,Grevemeyer，Ingo.,Morgan，Jason P..,...&Tao，Chunhui.(2023).Disparate crustal thicknesses beneath oceanic transform faults and adjacent fracture zones revealed by gravity anomalies.Geology,51(3),300-304.

Guo，Zhikui,et al."Disparate crustal thicknesses beneath oceanic transform faults and adjacent fracture zones revealed by gravity anomalies".Geology 51.3(2023):300-304.