Characteristics of the West Greenland Margin in the Southern Baffin Bay

Block, M.; Damm, Volkmar; Ehrhardt, A.; Berglar, Kai; Schnabel, M.; Altenbernd, Tabea

doi:10.3997/2214-4609.20148225

Cited by 2 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Characteristics of a volcanic margin typically are a high velocity lower crust (magmatic underplating) and seaward dipping reflector sequences of flood basalts, that formed at the initial break-up (Hopper et al 2003;Mjelde et al 2005;Voss et al 2009). Seaward dipping reflectors of flood basalt are imaged on the MCS data from 390 to 410 km (Block et al 2012), supporting an interpretation as volcanic margin, as does the discussion on magmatic underplating in the previous section.…”

Section: Greenland Transitional Crustsupporting

confidence: 75%

“…13). The Greenland continental margin is classified as a volcanic margin as no evidence of serpentinized mantle material is found and seaward dipping reflectors are imaged on the MCS data (Block et al 2012). Mafic intrusions in the lower crust are inferred from a P ‐wave velocity increase and support this interpretation.…”

Section: Discussionmentioning

confidence: 99%

“…The MCS data show a basement morphology with block faulting after a model distance of 430 km (Fig. 3) and from the distance of 390–410 km seaward dipping reflectors are imaged (Block et al 2012).…”

Section: Seismic Datamentioning

confidence: 98%

See 2 more Smart Citations

The crustal structure of southern Baffin Bay: implications from a seismic refraction experiment

Suckro¹,

Gohl²,

Funck

et al. 2012

Geophysical Journal International

View full text Add to dashboard Cite

SUMMARY Baffin Bay represents the northern extension of the extinct rift system in the Labrador Sea. While the extent of oceanic crust and magnetic spreading anomalies are well constrained in the Labrador Sea, no magnetic spreading anomalies have yet been identified in Baffin Bay. Thus, the nature and evolution of the Baffin Bay crust remain uncertain. To clearly characterize the crust in southern Baffin Bay, 42 ocean bottom seismographs were deployed along a 710‐km‐long seismic refraction line, from Baffin Island to Greenland. Multichannel seismic reflection, gravity and magnetic anomaly data were recorded along the same transect. Using forward modelling and inversion of observed traveltimes from dense airgun shots, a P‐wave velocity model was obtained. The detailed morphology of the basement was constrained using the seismic reflection data. A 2‐D density model supports and complements the P‐wave modelling. Sediments of up to 6 km in thickness with P‐wave velocities of 1.8–4.0 km s−1 are imaged in the centre of Baffin Bay. Oceanic crust underlies at least 305 km of the profile. The oceanic crust is 7.5 km thick on average and is modelled as three layers. Oceanic layer 2 ranges in P‐wave velocity from 4.8 to 6.4 km s−1 and is divided into basalts and dykes. Oceanic layer 3 displays P‐wave velocities of 6.4–7.2 km s−1. The Greenland continental crust is up to 25 km thick along the line and divided into an upper, middle and lower crust with P‐wave velocities from 5.3 to 7.0 km s−1. The upper and middle continental crust thin over a 120‐km‐wide continent–ocean transition zone. We classify this margin as a volcanic continental margin as seaward dipping reflectors are imaged from the seismic reflection data and mafic intrusions in the lower crust can be inferred from the seismic refraction data. The profile did not reach continental crust on the Baffin Island margin, which implies a transition zone of 150 km length at most. The new information on the extent of oceanic crust is used with published poles of rotation to develop a new kinematic model of the evolution of oceanic crust in southern Baffin Bay.

show abstract