Skip to main content
Go to the home page of the European Commission (opens in new window)
English en
CORDIS - EU research results
CORDIS

The ‘orphan’ boundary type in plate tectonics: oceanic transform faults reconstructed

Project description

Research could upend understanding of oceanic transform faults

The Plate Tectonic Revolution gave birth to three types of plate boundaries: mid-ocean ridges, subduction zones and oceanic transform faults (OTFs). OTFs have only been studied to a limited extent, but recent observations suggest they exhibit complex behaviours. OTF morphology and numerical modelling indicate they may evolve from a strike-slip fault at the surface to extensional features below. These strike-slip plate boundaries can generate valleys up to 18 km wide and 7 km deep, challenging our understanding of plate tectonics. The ERC-funded TRANSFORMERS project aims to explore these phenomena through extensive seismological, geodetic and geological surveys of the ocean floor. Project results could enable researchers to reclassify OTFs as two-stage accretion features, transforming our understanding of plate tectonics.

Objective

The plate tectonic revolution gave birth to three types of plate boundaries; two got most of the interest, i.e. the mid-ocean ridges where new ocean floor is formed and subduction zones where the lithosphere is recycled back into the Earth’s interior. In the oceans, the third type, the “simple” strike-slip conservative plate boundary or oceanic transform fault (OTF), was treated like an orphan in a Charles Dickens novel. However, recent observations challenge plate tectonics, revealing that OTFs show unexpected complex behaviour. The morphology of oceanic transform systems and numerical modelling suggests that OTFs are extensional below their strike-slip faults at the surface. Later in their evolution, before converting from an active fault into an inactive fracture zone at the ridge-transform intersection, OTFs may turn into accretionary features. Yet, how can a strike-slip plate boundary, generating magnitude >7 earthquakes, promote extension forming up to 18 km wide and 7 km deep valleys? Furthermore, a fault zone grading from a strike slip fault into an extensional feature at depth would be a unique geological feature and may control their major seismic slip deficit. TRANSFORMERS will reveal: (i) if OTFs are indeed wrongly classified in plate tectonics and are not conservative plate boundaries, but instead have to be re-classified as features where accretion occurs in two-stages, separated by a period of transform extension, revealing a process fundamentally different from predictions of plate tectonics, suggesting that fracture zones are structurally different from OTFs; (ii) how OTFs operate from top to bottom and why their seismic moment release is too low. The project will require major sea-going efforts, issuing seismological, geodetic and geological surveys on the ocean floor, mimicking a multiple year’s land campaign. The outcome will revolutionize our understanding of oceanic transform faults, adding a new chapter to plate tectonics.

Fields of science (EuroSciVoc)

Keywords

Programme(s)

Topic(s)

Funding Scheme

HORIZON-ERC - HORIZON ERC Grants

See all projects funded under this funding scheme

Call for proposal

(opens in new window) ERC-2022-ADG

See all projects funded under this call

Host institution

HELMHOLTZ-ZENTRUM FUR OZEANFORSCHUNG KIEL (GEOMAR)
Net EU contribution
€ 2 864 427,50
Address
WISCHHOFSTRASSE 1-3
24148 Kiel
Germany
Region
Schleswig-Holstein Schleswig-Holstein Kiel, Kreisfreie Stadt
Activity type
Research Organisations
Links
Total cost
€ 2 864 427,50

Beneficiaries (1)