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The stratigraphy and sedimentology of Jurassic to Tertiary sediments within the Laura and Carpentaria basins in northeastern Australia show that the continental drainage divide here predates the onset of continental margin formation and has remained stationary since the Middle Jurassic. This result is contrary to models of the evolution of highlands adjacent to passive continental margins that state that divide migration associated with downwarping of the highland flank and widespread stream reversals and/or captures should occur following margin development. The results also show that a maximum of only 50 m of denudation could have occurred on the continental drainage divide here since the Cretaceous. Keywords: passive margin, tectonics, continental drainage divide, denudation.

Objective: The aim of this review is to highlight an emerging problem with anticoagulation-related complications in neonatal and paediatric ECMO, to explore for flaws in the currently recommended anticoagulation management responsible for these problems and to discuss possible strategies mitigating further escalation of the issue. Data Sources: Pertinent neonatal and paediatric literature on the topic of interest and international Extracorporeal Life Support Organisation (ELSO) registry data request. Conclusions: The international ELSO registry data reveals increasing rates of anticoagulation-related complications during neonatal and paediatric ECMO worldwide. The causes are multifactorial and the proposed solution to the problem is to match anticoagulation management to the pathophysiological complexity of haemostasis on ECMO. [ABSTRACT FROM AUTHOR]

The horizontal-to-vertical (H/V) technique by Nakamura (1989) was applied to data from 30 new field stations and 64 other broadband temporary and permanent seismic stations within the Mississippi Embayment of the central United States to develop a 3D model of unconsolidated sediment shear-wave velocity structure. Using the Dart (1992) map of sediment thickness as a basis, two selfconsistent models of average shear-wave velocity versus sediment thickness were developed by utilizing the theoretical linear relationship between the frequency of the H/V peak and shear-wave velocity. One model was based on the observation that the H/V peak period Tp (s) versus sediment thickness h (m) was seen to be approximately linear with the relationship T p = 0.003266h + 1.084. The second model was developed by considering peak frequency f p versus sediment thickness parameterized to follow In /p = 8.325 × 10-7h² - 0.00232h - 0.01796. Overall, the models show low-average shear-wave velocity near the edge of the Mississippi Embayment with velocities increasing with increasing sediment thickness, consistent with increased sediment compaction. These models will be useful in studies of site resonance and amplification for earthquake-shaking hazards and for wave propagation computations for the region. [ABSTRACT FROM AUTHOR]

Ambient ground-motion data were collected using phased seismic arrays in fall 2002 and spring 2007 within the Mississippi embayment and at a single station external to the embayment. These data allowed us to determine the wave-field composition of ambient noise for understanding wave-propagation mechanisms giving rise to spectral peaks using Nakamura's HIV technique. Ambient ground motions in the frequency band of 0.1-0.33 Hz (10-3 sec period) were dominated by spatially localized Rayleigh- and Love-wave microseisms generated by high-ocean waves along the North American seaboard in the time periods of analysis. Seismic waves important in forming the H/V peak near 4 sec period are composed of relatively high-phase velocity Rayleigh and Love waves that convert to propagating homogeneous shear waves in the thick unconsolidated sediments of the embayment. The H/V resonant period is controlled by both constructive and destructive interference of these shear waves. A simple relationship for the H/V peak is given using a propagator matrix formulation that predicts the resonance frequency of a layered medium for surface wave motion at the base of the system. The amplitude of the observed H/V peak, however, does not give an accurate estimate of shear-wave amplification because it depends on the slowness of the incident wave. The inconsistency in estimated average shear-wave velocities using the H/V method and differential travel times of local earthquake Sp phases in the Mississippi embayment may be explained by misidentification of Sp-wave conversion points from deeper interfaces. [ABSTRACT FROM AUTHOR]

This article describes an unusually well-behaved, unusually well-documented central and eastern United States (CEUS) earthquake sequence. Detailed analysis of regional and local waveform data from the 6 June 2003 Bardwell, Kentucky, earthquake indicates that the mainshock has the seismic moment of M0 1.3 (± 0.5) x 1015 N m (Mw 4.0) and occurred at a depth of about 2 (± 1) km on a near-vertical fault plane. A temporary seismic network recorded 85 aftershocks that delineate an east-trending fault approximately 1 km in length. The hypocenters illuminate a vertical plane between 2.0 and 2.7 km depth. The centroid of the aftershock distribution is at 36.875° N, 89.010° W and a depth of 2.4 km. The aftershock cluster is interpreted as a circular fault area with a radius of 0.44 (± 0.03) km. This source radius yields a static stress drop, Δσ = 67 (± 14) bars for the mainshock. The focal mechanism for the mainshock has strike = 90°, dip = 89°, and rake = - 165° with a subhorizontal P axis trending 135°. A formal stress inversion based on the focal mechanisms of the mainshock and ten aftershocks indicates the maximum compressive stress trends 104° with a plunge of 5°. The local stress field near Bardwell is therefore rotated about 40° clockwise relative to 65° for eastern North America as a whole. The Bardwell earthquakes have the opposite sense of slip to earthquakes with east-trending nodal planes that occur near New Madrid, Missouri. This requires a significant local rotation of the stress field over a distance of 60 km. [ABSTRACT FROM AUTHOR]