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| Jones, Ejw; Siddall, R; Thirlwall, Mf; Chroston, Pn; Lloyd, Aj. |
| Seismic data from the flat-topped Anton Dohrn Seamount in the central Rockall Trough reveal that the feature is capped by a thin (approximately 100 m) sedimentary layer which covers an extensive erosion surface lying approximately 800 m below sea level. The surface of erosion truncates a volcanic sequence that outcrops on the eastern side of the seamount to form a well-defined terrace from which alkali basalts and chalks of late Cretaceous age have been recovered. A refraction profile shot over the summit plateau and ultrasonic measurements on the basalts suggest that sedimentary and volcanoclastic units are abundant constituents of a low-velocity (3.69 km s-1) volcanic core which persists to depths of over 1 500 m. The seamount differs from the shallow... |
| Tipo: Text |
Palavras-chave: ATLANTIC; BASALTS; GUYOT; RIFTING; ROCKALL. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00098/20887/18501.pdf |
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| Knutz, Pc; Austin, Wen; Jones, Ejw. |
| Lithology, lithic petrology, planktonic foraminiferal abundances, and elastic grain sizes have been determined in a 30 m-long core recovered from the Barra Fan off northwest Scotland. The record extends back to around 45 kyr B.P., with sedimentation rates ranging between 50 and 200 cm/kyr. The abundance of ice-rafted debris indicates 16 glacimarine events, including temporal equivalents to Heinrich events 1-4. Enhanced concentrations of basaltic material derived from the British Tertiary Province suggest that the glacimarine sediments record variations in a glacial source on the Hebrides shelf margin. Glacimarine zones are separated by silty intervals with high planktonic foraminifera concentrations that reflect an interstadial circulation regime in the... |
| Tipo: Text |
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| Ano: 2001 |
URL: https://archimer.ifremer.fr/doc/00220/33174/31680.pdf |
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