The occurrence of the dinoflagellate cyst
            <i>Apectodinium</i>
            (Costa &amp; Downie 1976) Lentin &amp; Williams 1977 in the Moray and Montrose Groups (Danian to Thanetian) of the UK central North Sea

Thomas, Joanna E.

doi:10.1144/gsl.sp.1996.101.01.07

Cited by 9 publications

(4 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Several occurrences of Apectodinium spp. have been reported at stratigraphic levels below the Base Apectodinium Datum, and A. homomorphum occurs in strata of Danian age in the Maureen Formation of the central North Sea (Thomas, 1996). Given these uncertainties, it is likely that the basalts and picrites of the Lower Series at Kangerlussuaq are substantially older than the previous studies suggest.…”

Section: Age Of the Igneous Basementmentioning

confidence: 76%

Magmatic development of the southeast Greenland Margin and evolution of the Iceland Plume: geochemical constraints from Leg 152

Saunders¹,

Larsen²,

Fitton³

1998

Proceedings of the Ocean Drilling Program

View full text Add to dashboard Cite

Leg 152, located on the southeast Greenland Margin, successfully recovered igneous rocks from three drill sites along a transect at 63°N: 915, 917, and 918. The margin is characterized by a 150-km-wide sequence of seaward-dipping reflectors (SDRS), and thus has an architecture typical of volcanic rifted margins. Site 917 was located close to the inboard, feather-edge of the SDRS, on the continental shelf, and drilling recovered rocks ranging in composition from picrite to dacite. Site 915 was immediately oceanward of Site 917, and Site 918 was located on the continental rise, in the main sequence of the SDRS. Drilling at both Sites 915 and 918 recovered basalt. Ash horizons were cored in the sediment column at Site 918 and Site 919 in the Irminger Basin. The oldest recovered lavas (the Lower and Middle Series from Site 917), erupted approximately 61 m.y. ago, sit on steeply dipping pre-rift metasediments. They are variably contaminated by ancient amphibolite-and granulite-facies crust, consistent with eruption in a continental setting before plate breakup. A few of the Lower Series lavas are high-MgO basalts. The amount of contamination decreased dramatically in the succeeding Upper Series lavas, which also show evidence for a rapid shallowing of the average depth of melting, and contain a high proportion of picrites and high-MgO basalts. These observations are consistent with attenuation of the lithosphere and rapid egress of magmas to the surface during eruption of the Upper Series lavas. Basalt from Site 915 is only slightly contaminated by continental crust, and basalts from Site 918, erupted during C24r time (approximately 56−53 Ma), are uncontaminated. The eruption environment and the composition of the lavas indicate a clear role for the Iceland plume, in that (1) some lava flows from the Lower and Upper Series at Site 917 represent high-MgO magmas and, by inference, had high liquidus and source temperatures; (2) the main sequence of the SDRS were erupted subaerially, thus requiring support from hot, buoyant mantle; and (3) the basalts from Sites 915 and 918 more closely resemble depleted Icelandic tholeiites than normal mid-oceanridge basalts. Leg 152 has shown that igneous activity was under way by 61 Ma on the southeast Greenland Margin, at the same time as in West Greenland and the British Isles, over 2000 km apart in their pre-drift locations.

show abstract

Section: Age Of the Igneous Basementmentioning

confidence: 76%

Magmatic development of the southeast Greenland Margin and evolution of the Iceland Plume: geochemical constraints from Leg 152

Saunders¹,

Larsen²,

Fitton³

1998

Proceedings of the Ocean Drilling Program

View full text Add to dashboard Cite

show abstract

“…This is consistent with an Early Eocene age for A.a . in the northern North Sea and is supported by several authors [e.g., Mudge and Copestake , ; Gradstein et al ., ; Mudge and Bujak , ; Neal , ; Thomas , ]. A.m .…”

Section: Data Processing and Methodsmentioning

confidence: 99%

Incipient mantle plume evolution: Constraints from ancient landscapes buried beneath the North Sea

Quay

Watson

Jackson

2017

Geochem Geophys Geosyst

View full text Add to dashboard Cite

Geological observations that constrain the history of mantle convection are sparse despite its importance in determining vertical and horizontal plate motions, plate rheology, and magmatism. We use a suite of geological and geophysical observations from the northern North Sea to constrain evolution of the incipient Paleocene-Eocene Icelandic plume. Well data and a three-dimensional seismic survey are used to reconstruct a 58-55 Ma landscape now buried 1.5 km beneath the seabed in the Bressay region. Geochemical analyses of cuttings from wells that intersect the landscape indicate the presence of angiosperm debris. These observations, combined with presence of coarse clastic material, interpreted beach ridges, and a large dendritic drainage network, indicate that this landscape formed subaerially. Longitudinal profiles of paleo-rivers were extracted and inverted for an uplift rate history, indicating three distinct phases of uplift and total cumulative uplift of 350 m. Dinoflagellate cysts in the surrounding marine stratigraphy indicate that this terrestrial landscape formed in <3 Ma and was rapidly drowned. This uplift history is similar to that of a slightly older buried landscape in the Faeroe-Shetland basin 400 km to the west. These records of vertical motion are consistent with pulses of anomalously hot asthenosphere spreading out from the incipient Icelandic plume. Using simple isostatic calculations, we estimate that the maximum thermal anomaly beneath Bressay was 50-1008C. Our observations suggest that a thermal anomaly departed the Icelandic plume around 57.4 6 2.2 Ma at the latest and travelled with a velocity > 150 km/Ma.

show abstract

“…The changes in microfaunal abundance and diversity are accompanied by changes in the palynomorph assemblages (Thomas 1996), with the upward transition from greenish claystone to grey mudstone being marked by a dramatic increase in the ratio of terrestrial to marine forms. This feature persists to the top of the lower division of the Sele Formation (unit Sla of Knox & Holloway 1992), above which the turbidite sandstone unit is characterized by an increase in the proportion of marine forms and by the incoming of the genus Apectodinium.…”

Section: The Basinal Record Of the Central North Seamentioning

confidence: 99%

“…The marked increase in the proportion of terrestrial palynomorphs can be interpreted in terms of increased terrestrial run-off, resulting from either sea-level fall or climatic change. According to some interpretations, the increase in relative abundance of Apectodinium might be an indicator of warming, but other factors, such as sea-level change, may also be involved (Thomas 1996). However, an increase in temperature around the S 1 a/S l b boundary has previously been inferred by Schrrder (1992) from the composition of the palynomorph assemblages, and fluctuations in the composition of the palynomorph assemblages reported from the remainder of the Slb section (Forties Sandstone) may also be of climatic origin (Wood & Tyson 1996).…”

Section: The Basinal Record Of the Central North Seamentioning

confidence: 99%

Correlation of the early Paleogene in northwest Europe: an overview

Knox

1996

View full text Add to dashboard Cite

The occurrence of the dinoflagellate cyst Apectodinium (Costa & Downie 1976) Lentin & Williams 1977 in the Moray and Montrose Groups (Danian to Thanetian) of the UK central North Sea

Cited by 9 publications

References 10 publications

Magmatic development of the southeast Greenland Margin and evolution of the Iceland Plume: geochemical constraints from Leg 152

Magmatic development of the southeast Greenland Margin and evolution of the Iceland Plume: geochemical constraints from Leg 152

Incipient mantle plume evolution: Constraints from ancient landscapes buried beneath the North Sea

Correlation of the early Paleogene in northwest Europe: an overview

Contact Info

Product

Resources

About