171,667 research outputs found
U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin. Cruise Report for 2008
USCGC Icebreaker Healy (WAGB-20)
U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin
CRUISES HE-0805
August 14 to September 5, 2008
Barrow, AK to Barrow, A
U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin. Cruise Report for 2008
USCGC Icebreaker Healy (WAGB-20)
U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin
CRUISES HE-0805
August 14 to September 5, 2008
Barrow, AK to Barrow, A
The Stratigraphic Record of Pre-breakup Geodynamics: Evidence from the Barrow Delta, offshore Northwest Australia
The structural and stratigraphic evolution of rift basins and passive margins has been widely studied, with many analyses demonstrating that delta systems can provide important records of post-rift geodynamic processes. However, the apparent lack of ancient syn-breakup delta systems and the paucity of seismic imaging across continent-ocean boundaries means the transition from continental rifting to oceanic spreading remains poorly understood. The Early Cretaceous Barrow Group of the North Carnarvon Basin, offshore NW Australia was a major deltaic system that formed during the latter stages of continental rifting, and represents a rich sedimentary archive, documenting uplift, subsidence and erosion of the margin. We use a regional database of 2D and 3D seismic and well data to constrain the internal architecture of the Barrow Group. Our results highlight three major depocentres: the Exmouth and Barrow sub-basins, and southern Exmouth Plateau. Over-compaction of pre-Cretaceous sedimentary rocks in the South Carnarvon Basin, and pervasive reworking of Permian and Triassic palynomorphs in the offshore Barrow Group, suggests that the onshore South Carnarvon Basin originally contained a thicker sedimentary succession, which was uplifted and eroded prior to breakup. Backstripping of sedimentary successions encountered in wells in the Exmouth Plateau depocentre indicate anomalously rapid tectonic subsidence (≤0.24 mm yr-1) accommodated Barrow Group deposition, despite evidence for minimal, contemporaneous upper crustal extension. Our results suggest that classic models of uniform extension cannot account for the observations of uplift and subsidence in the North Carnarvon Basin, and may indicate a period of depth-dependent extension or dynamic topography preceding breakup
Serious mortality: the date of the Fussell's Lodge long barrow
Twenty-seven radiocarbon results are now available from the Fussell’s Lodge long barrow, and are presented within an interpretive Bayesian statistical framework. Three alternative archaeological interpretations of the sequence are given, each with a separate Bayesian model. It is hard to decide between these, though we prefer the third. In the first (following the excavator), the construction is a unitary one, and the human remains included are by definition already old. In the second, the primary mortuary structure is seen as having two phases, and is set within a timber enclosure; these are later closed by the construction of a long barrow. In that model of the sequence, deposition began in the 38th century cal BC and the mortuary structure was extended probably in the 3660s–3650s cal BC; the long barrow was probably built in the 3630s–3620s cal BC; ancestral remains are not in question; and the use of the primary structure may have lasted for a century or so. In the third, preferred model, a variant of the second, we envisage the inclusion of some ancestral remains in the primary mortuary structure alongside fresh remains. This provides different estimates of the date of initial construction (probably in the last quarter of the 38th century cal BC or the first half of the 37th century cal BC) and the duration of primary use, but agrees in setting the date of the long barrow probably in the 3630s–3620s cal BC. These results are discussed in relation to the development and meanings of long barrows at both national and local scales
U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin, cruise report for 2009
U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin
CRUISES HE-0905
August 7 to September 16, 2009
Barrow, AK to Barrow, A
U.S. Law of the Sea Cruise to Map the Foot of the Slope and 2500-m Isobath of the U.S. Arctic Ocean Margin, Barrow to Barrow. Cruise Report
U.S. Law of the Sea cruise to map the foot of the slope and 2500-m isobath of the US Arctic Ocean margin
CRUISES HE-0302
August 30 to September 11, 2003
Barrow, AK to Barrow, A
Evolution of the Bianchi I, the Bianchi III and the Kantowski-Sachs Universe: Isotropization and Inflation
We study the Einstein-Klein-Gordon equations for a convex positive potential
in a Bianchi I, a Bianchi III and a Kantowski-Sachs universe. After analysing
the inherent properties of the system of differential equations, the study of
the asymptotic behaviors of the solutions and their stability is done for an
exponential potential. The results are compared with those of Burd and Barrow.
In contrast with their results, we show that for the BI case isotropy can be
reached without inflation and we find new critical points which lead to new
exact solutions. On the other hand we recover the result of Burd and Barrow
that if inflation occurs then isotropy is always reached. The numerical
integration is also done and all the asymptotical behaviors are confirmed.Comment: 22 pages, 12 figures, Self-consistent Latex2e File. To be published
in Phys. Rev.
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