Sedimentary regimes at the Macquarie Ridge Complex: Interaction of Southern Ocean circulation and plate boundary bathymetry

Schuur, Catherine L.; Coffin, Millard F.; Frohlich, Clifford A; Massell, C.; Karner, Garry D.; Ramsay, Doug; Caress, David W.

doi:10.1029/98pa02357

Cited by 27 publications

(20 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hayes and Talwani [1972] concluded that the tectonics of the Hjort Trench are dominantly transcurrent with a secondary compressive component, and that various portions of the MRC may represent each of the previously proposed models. This recognition of the complex variability of tectonic interpretations directed subsequent, detailed structural and morphologic research of specific portions of the MRC, as well as the kinematic evolution of the different segments of the boundary (e.g., Puysegur, McDougall, Macquarie, and Hjort regions; Figures 1 and 2 [ Sutherland , 1995; Collot et al , 1995; Delteil et al , 1996; Frohlich et al , 1997; Lamarche et al , 1997; Lebrun et al , 1998; Schuur et al , 1998; Melhuish et al , 1999; Lamarche and Lebrun , 2000; Massell et al , 2000; Bernardel and Symonds , 2001].…”

Section: Geodynamic Setting and Previous Researchmentioning

confidence: 99%

Underthrusting at the Hjort Trench, Australian‐Pacific plate boundary: Incipient subduction?

Meckel

Coffin

Mosher

et al. 2003

Geochem Geophys Geosyst

View full text Add to dashboard Cite

The southernmost portion of the Macquarie Ridge Complex (MRC) comprises the Hjort Ridge, Trench, and Plateau, the topographic expression of the Australian‐Pacific plate boundary south of New Zealand. On the basis of marine geophysical (swath bathymetry/reflectivity, seismic reflection, gravity, magnetic) data, teleseismic data, and gravity modeling, we argue that the Australian plate is actively underthrusting the Pacific plate along the Hjort Trench, but self‐sustaining subduction does not yet appear to have commenced. We interpret a crustal discontinuity in the Trench as a shallowly dipping thrust splay off a sub‐vertical transform fault in the crest of the Hjort Ridge (Hjort Fault). The Hjort Fault separates oceanic crust generated at the Southeast Indian Ridge (SEIR crust), located to the south, from oceanic crust generated at the extinct Australian‐Pacific spreading center located to the north (MRC crust). Oblique convergence on the transform has initiated a significant plate boundary decollement in the Trench, but our estimate of ∼50 km of underthrusting does not support the existence of an eastwardly dipping Australian slab below ∼20 km depth. For the length of the Hjort Ridge and Trench system, oblique convergence is partitioned between the decollement in the Trench and the Hjort Fault. South of 57.5°S, the trench decollement accommodates thrusting. North of 57.5°S, the boundary‐parallel component of convergence becomes dominant, the Trench gradually shallows, and the trench decollement evolves into a low‐angle, oblique‐slip fault. The trench decollement and strike‐slip system in the Hjort Ridge are structural boundaries that contain tectonic slivers of inferred SEIR crust of the western flank of the Hjort Ridge that currently belong to neither the Australian nor the Pacific plates.

show abstract

Section: Geodynamic Setting and Previous Researchmentioning

confidence: 99%

Underthrusting at the Hjort Trench, Australian‐Pacific plate boundary: Incipient subduction?

Meckel

Coffin

Mosher

et al. 2003

Geochem Geophys Geosyst

View full text Add to dashboard Cite

show abstract

“…1). Beginning in the Southern Ocean, they pass through and around the Macquarie Ridge system (Schuur et al 1998), impinge against the flank of the Campbell Plateau, and then flow northeastward towards the Bollons Seamount (Carter & McCave 1997;Carter & Wilkin 1999). Extensive nodule fields in this region have been described previously (Summerhayes 1967;Goodell et al 1973;Glasby 1976a;Piper etal.…”

Section: Introductionmentioning

confidence: 82%

“…with the subsequent confined vigorous and erosive flow of the ACC/DWBC into the Solander Trough at c. 3.3 Ma, therefore removing part of the Solander Fan(Schuur et al 1998). These eroded sediments may have subsequently nourished the DWBC bedload.…”

mentioning

confidence: 97%

Occurrence and physical setting of ferromanganese nodules beneath the Deep Western Boundary Current, Southwest Pacific Ocean

Wright

Graham

Chang

et al. 2005

New Zealand Journal of Geology and Geophysics

View full text Add to dashboard Cite

show abstract

“…The primary data source we use in our analysis is swath bathymetry collected during four marine geophysical surveys of the Macquarie Ridge Complex: the 1993 cruise of the L'Atalante (Geodynz‐sud [ Collot et al , 1995; Lebrun et al , 1998]), the 1994 cruise of R/V Rig Seismic 124 [ Coffin et al , 1994; Frohlich et al , 1997; Schuur et al , 1998; Massell et al , 2000], 1996 cruise of R/V Maurice Ewing 9513 [ Massell et al , 2000], and the 2000 cruise of R/V L'Atalante AUSTREA‐2 [ Bernardel et al , 2000; Bernardel and Symonds , 2001; Meckel et al , 2003]. These swath data have been merged with predicted bathymetry [ Smith and Sandwell , 1997] to create a digital bathymetry grid between 45°S to 61°S and 155°E to 167°E (Figure 2).…”

Section: Datamentioning

confidence: 99%

“…Measured and predicted values were used to construct a Triangular Irregular Network (TIN) surface satisfying the Delaunay triangle criterion, allowing the highest resolution from each survey to be retained within the merged data set. Seafloor sediment distribution and thickness is generally quite well known from reflectivity and multichannel seismic surveys in the study area [e.g., Schuur et al , 1998], with the thickest accumulations in the Hjort Trench (up to 1.5 km) [ Meckel et al , 2003]. Magnetic anomaly data used to infer the age of the crust adjacent to the MRC is from Weissel et al [1977], Wood et al [1996], and Keller [2004].…”

Section: Datamentioning

confidence: 99%

Influence of cumulative convergence on lithospheric thrust fault development and topography along the Australian‐Pacific plate boundary south of New Zealand

Meckel

Mann

Mosher

et al. 2005

Geochem Geophys Geosyst

Self Cite

View full text Add to dashboard Cite

[1] The development of faulting and topography resulting from initial convergence within oceanic lithosphere is largely unknown. We explore relationships among convergence, structural development, and topography along $1500 km of the submarine Australian-Pacific plate boundary south of New Zealand, the Macquarie Ridge Complex (MRC). Due to the variable orientation of the boundary and close proximity of the Australian-Pacific poles of rotation, individual segments of the plate boundary have experienced different convergence histories since $10.95 Ma (Chron 5o). Because interaction along the oceanic extent of the boundary involves oceanic lithosphere of broadly the same age and therefore thermal structure, structural and morphologic differences can be attributed primarily to variations in angles and rates of convergence with respect to the plate boundary orientation since 10.95 Ma. We relate plate boundarynormal convergence determined from stage pole rotations to structural development, focusing on transitions from purely strike-slip faulting to partitioned thrust and strike-slip faulting between 47°S and 60°S since 10.95 Ma. Our results indicate that boundary-normal convergence of $100 km marks the transition from strike-slip dominated faulting to partitioned underthrusting and strike-slip faulting (incipient subduction). Establishment of subduction at the Puysegur Trench and incipient subduction at the Hjort Trench corresponds to convergence at rates between $2 and 4 cm/yr, angles >30°, and with durations of at least 10 m.y., resulting in >100 km of boundary-normal convergence. Anomalous topographic volumes resulting from tectonic deformation are quantified from swath bathymetry and compared to convergence history. Results from analysis of the central MRC suggest that prior to lithospheric-scale thrust faulting, $100 km of boundary-normal convergence can be accommodated by crustal deformation (6 km relief from ridge crest to adjacent trough) and strike-slip faulting. Our research supports induced/ forced intraoceanic initiation of subduction.

show abstract

Sedimentary regimes at the Macquarie Ridge Complex: Interaction of Southern Ocean circulation and plate boundary bathymetry

Cited by 27 publications

References 64 publications

Underthrusting at the Hjort Trench, Australian‐Pacific plate boundary: Incipient subduction?

Underthrusting at the Hjort Trench, Australian‐Pacific plate boundary: Incipient subduction?

Occurrence and physical setting of ferromanganese nodules beneath the Deep Western Boundary Current, Southwest Pacific Ocean

Influence of cumulative convergence on lithospheric thrust fault development and topography along the Australian‐Pacific plate boundary south of New Zealand

Contact Info

Product

Resources

About