Volcanic ash in a cored borehole W of the Shetland Islands: evidence for Selandian (late Palaeocene) volcanism in the Faeroes region

Morton, A. C.; Evans, David; Harland, Rex; King, Chris; Ritchie, D.

doi:10.1144/gsl.sp.1988.039.01.24

Cited by 15 publications

(31 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…strikingly similar to the lower series at Site 642 (Morton et al, 1988a). Below a sequence of Holocene to upper Paleocene sediments, the well was drilled through about 700 m of extrusive basalts before penetrating 356 m into dacites.…”

Section: Upper and Lower Seriessupporting

confidence: 55%

“…The main basalts are also olivine tholeiites, but with a composition quite similar to normal mid-ocean ridge basalt. According to Morton et al (1988a), the lower, homogeneous cordierite-phyric dacites originate from melting at depth of argillaceous, possibly also arenaceous, rocks. K-Ar dating gives ages in the range 51-58 Ma, averaging 55 Ma, without significant differences between the basalts and dacites.…”

Section: Upper and Lower Seriesmentioning

confidence: 99%

See 1 more Smart Citation

Evolution of the Vøring Volcanic Margin

Eldholm¹,

Thiede²,

Taylor³

1989

Proceedings of the Ocean Drilling Program

136

107

View full text Add to dashboard Cite

ODP Sites 642 and 643 recovered a succession of rocks which have greatly improved the understanding of how the Cenozoic volcanic Wring Margin evolved, particularly by providing important constraints on the series of events that occurred during the initial opening of the Norwegian-Greenland Sea. The more than 900 m of igneous rocks and interbedded sediments drilled at Site 642 constitute two distinct, strikingly different volcanic series. The upper series, composed of transitional mid-oceanic tholeiitic lava flows and thin interbedded volcaniclastic sediments confirmed the seaward-dipping reflectors to be a terrestrially constructed extrusive complex. The lower series, probably extending for several hundred meters below the bottom of the hole, consists of another flow complex of dacitic composition, some dikes and thicker interbedded sediments, partially continentally derived. We suggest that the margin evolved by crustal extension in the Paleocene accompanied by uplift and a progressively more intense invasion of dikes and sills in the rift zone. Just prior to breakup, magma from shallow crustal melts produced the lower series. The upper series was constructed during an intense, rapidly waning, volcanic surge of subaerial accretion of oceanic magma following breakup in middle of Chron 24.2R. The surge is characterized by a much increased rate of magma production and high spreading rate. The upper series cover both newly formed oceanic crust and large areas of the adjacent thinned continental crust. The dipping wedge was formed by subsidence due to loading and thermal contraction, possibly amplified by a tectonic force. When the surge had abated, the injection center quickly subsided and normal oceanic crust was formed. Our interpretation is that the continent/ocean boundary occurs at the seaward termination of reflector K, which separates the two volcanic series. However, a region of strongly intruded transitional crust is inferred in 30-to 50-km wide zones on either side of the Vdring Plateau Escarpment.The Wring Margin experienced crustal uplift and extension prior to breakup, restricted to a Tertiary marginal basin west of the present shelf edge. The initial volcanic surge and shallow extrusion level are related to a higher than normal temperature at the base of the lithosphere, inducing partial melting combined with opening in previously thinned crust. The commonly described non-extensional nature of this margin is only an apparent phenomenon. Except for the outer basin, extension by dike injection coupled with high strength of the thin, pre-opening crust in the Vdring Basin precluded the formation of a faulted rift unconformity. We believe these observations have relevance for volcanic margins elsewhere, but infer that seaward-dipping reflectors can form in many environments.The Wring Plateau marginal high and other similar features in the North Atlantic are an integrated part of the North Atlantic Volcanic Province, which extends 2000 km longitudinally. Compared to the central, transverse, part of ...

show abstract

Section: Upper and Lower Seriessupporting

confidence: 55%

Section: Upper and Lower Seriesmentioning

confidence: 99%

Evolution of the Vøring Volcanic Margin

Eldholm¹,

Thiede²,

Taylor³

1989

Proceedings of the Ocean Drilling Program

136

107

View full text Add to dashboard Cite

show abstract

“…A compilation of the new radiometric ages presented here, published NAVP lava ages, and fossil ages of ash layers in sediments in the North Sea (Knox and Morton, 1988;Morton et al, 1988) indicate that the bulk of the province is the product of two distinct pulses of magmatism, one occurring prior to 60 Ma and the other beginning around 57 Ma (Fig. 7).…”

Section: North Atlantic Volcanismmentioning

confidence: 72%

“…. Compilation of new radiometric ages presented in this paper and published ages from West Greenland (Larsen et al, 1992), East Greenland (Noble et al, 1988;Hansen et al, 1993;Upton et al, 1995), northwest Britain (Dagley and Mussett, 1986;Mussett, 1986), the Vøring Plateau (Boulter and Manum, 1989), and North Sea sediments (Knox and Morton, 1988;Morton et al, 1988). We cannot discount older ages in the eastern Atlantic SDRS because the lower lavas were not sampled.…”

Section: Discussionmentioning

confidence: 92%

40 Ar- 39 Ar ages of lavas from the southeast Greenland Margin, ODP Leg 152, and the Rockall Plateau, DSDP Leg 81

Sinton¹,

Duncan²

1998

Proceedings of the Ocean Drilling Program

View full text Add to dashboard Cite

ABSTRACT40 Ar incremental heating experiments were performed on volcanic rocks recovered by drilling during Ocean Drilling Program Leg 152, southeast Greenland Margin (63°N), and Deep Sea Drilling Project Leg 81, southwest Rockall Plateau (56°N). Both of these legs drilled into thick sections of submerged lava flows, known as seaward-dipping reflector sequences, that are part of the Tertiary North Atlantic Volcanic Province (NAVP). Results show that subaerial volcanism began at the southeast Greenland Margin as early as 61−62 Ma with the eruption of continentally contaminated lavas. After an apparent hiatus, volcanism continued with the subaerial eruption of noncontaminated, mid-ocean-ridge basalt (MORB) -like lavas. A sill or flow was emplaced at 52 Ma into the sediments overlying the basement lavas at the most seaward site (918). The MORB-like lavas of the Rockall Plateau gave poor results, although the data suggest that they erupted at 57−58 Ma and may be contemporaneous with the compositionally similar oceanic lavas of Leg 152.Compiled ages from the NAVP indicate that most of the lavas were erupted in two distinct magmatic episodes. The first occurred prior to 60 Ma with volcanism at the southeast Greenland Margin, in West Greenland, and the northwest British Isles. This early stage of widespread volcanism most likely records the arrival of the Iceland mantle plume. The second phase of magmatism began about 57 Ma with voluminous basaltic eruptions centralized along the eventual line of continental separation. Magmatism at this stage was associated with continental breakup and asthenospheric upwelling with probable thermal input from the mantle plume.

show abstract

“…3). While Morton et al (1988) discounted the British Tertiary Igneous Province as a source of these ashes on the basis of geochemical evidence, an east Greenland-Faroe Islands origin was regarded as plausible. However, the age of the onshore Faroe Islands and East Greenland lava fields discounts them as a source for these ashes, suggesting an as yet unidentified igneous centre in the offshore NE Atlantic.…”

mentioning

confidence: 99%

The evolution of the North Atlantic Igneous Province and the opening of the NE Atlantic rift

Jolley

Bell

2002

View full text Add to dashboard Cite

Volcanic ash in a cored borehole W of the Shetland Islands: evidence for Selandian (late Palaeocene) volcanism in the Faeroes region

Cited by 15 publications

References 15 publications

Evolution of the Vøring Volcanic Margin

Evolution of the Vøring Volcanic Margin

40 Ar- 39 Ar ages of lavas from the southeast Greenland Margin, ODP Leg 152, and the Rockall Plateau, DSDP Leg 81

The evolution of the North Atlantic Igneous Province and the opening of the NE Atlantic rift

Contact Info

Product

Resources

About