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81.
S.B. Nielsen K. Gallagher D.L. Egholm O.R. Clausen M. Summerfield 《Journal of Geodynamics》2009,48(2):101-106
In this reply, we address the issues raise by the comment of Lidmar-Bergström and Bonow [Lidmar-Bergström, K., Bonow, J., 2009. Hypotheses and observations on the origin of the landscape of southern Norway – a reply regarding the isostasy–climate–erosion hypothesis by Nielsen et al., 2008. Journal of Geodynamics, in press]. We reject them and maintain all our suggestions regarding western Scandinavia unaltered. 相似文献
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83.
Aisling Gallagher 《New Zealand geographer》2017,73(1):15-24
There has been a significant growth in childcare in New Zealand (NZ) since 2006. Shaped by debates around the marketisation of childcare, this paper will make some key observations about the NZ childcare market. I will argue that the landscape of childcare has changed in favour of a burgeoning private sector and consider the recent impetus for corporatisation. Finally, I will examine the discourse of parental ‘choice’ which pervades policy discussions around ECE in New Zealand and how this plays out in the face of an expanding private for‐profit sector. 相似文献
84.
Centimeter-Level Positioning of a U. S. Coast Guard Buoy Tender 总被引:1,自引:1,他引:0
David B. Zilkoski J. Don D'Onofrio Rudolf J. Fury Curtis L. Smith Lloyd C. Huff Barry J. Gallagher 《GPS Solutions》1999,3(2):53-65
With the availability of high-accuracy, differential global positioning system (GPS) results in real-time, there is a new
opportunity to use GPS to accurately measure a marine vessel's dynamic draft (settlement and squat) and 3D attitude (roll,
pitch, and heading). The National Geodetic Survey (NGS) and the Coast Survey (CS), offices of the National Ocean Service (NOS),
National Oceanic and Atmospheric Administration (NOAA), propose to transfer this technology to the shipping industry. The
overall goal of this project is to provide the position of a vessel's keel in real time to within 10 cm (about 4 inches) relative
to the bottom of the shipping channel.
In support of this phase of the project, there were three meetings hosted by the Port of Oakland, California and NOS to discuss
the real-time positioning of vessels project. On December 3 and 4, 1996, CS, NGS, Trimble Navigation Ltd., and the U. S. Coast
Guard (USCG) performed GPS tests on a USCG buoy-tender ship. GPS data were used to compute the vessel's dynamic draft and
3D attitude. During the test, five receivers continually collected data; one receiver was located at a base station on the
USCG pier on Yerba Buena Island, and four were on the ship: two on the stern and two on the bow. CS installed a TSS-335B vertical
reference unit (to measure heave, pitch, and roll) in the engine room of the ship.
NOS processed the GPS data and computed the vessel's dynamic draft and 3D attitude. The results indicate that the linear equivalent
to the vessel's dynamic draft and 3D attitude were accurate to the 10-cm level using GPS. It was also demonstrated how a ship
can be used to measure local water-level changes and actual water-level values everywhere it travels. ? 1999 John Wiley &
Sons, Inc. 相似文献
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86.
Abstract The Jurassic-Cretaceous subsidence history of the Eromanga Basin, a large intracratonic sedimentary basin in central eastern Australia, has been examined using standard backstripping techniques, allowing for porosity reduction by compaction and cementation. Interpretation of the results suggests that during the Jurassic the basin was subsiding in a manner consistent with the exponentially decreasing form predicted by simple thermally based tectonic models. By the Early Cretaceous, the rate of subsidence was considerably higher than that expected from such models and nearly half of the total sediment thickness was deposited over the final 20 Myr of the basin's 95 Myr Mesozoic depositional history. The Early Cretaceous also marks the first marine incursion into the basin, consistent with global sea-level curves. Subsequently, however, the sediments alternate between marine and non-marine, with up to 1200 m of fluvial sediments being deposited, and this was followed by a depositional hiatus of about 50 Myr in the Late Cretaceous. This occurred at a time when global sea-level was rising to its peak. A model is presented which is consistent with the rapid increase in tectonic subsidence rate and the transgressive-regressive nature of the sediments. The model incorporates a sediment influx which is greater than that predicted by the thermally based tectonic models implied by the Jurassic subsidence history. The excess sedimentation results in the basin region attaining an elevation which exceeds that of the contemporary sea-level, and thereby giving the appearance of a regression. The present day elevation of the region predicted by the model is about 100–200 m above that observed. This discrepancy may arise because the primary tectonic subsidence is better represented by a linear function of time rather than an exponentially decreasing form. 相似文献
87.
88.
Brent Gallagher 《地球物理与天体物理流体动力学》2013,107(1):347-354
AbstractPhotographs are presented which show a series of small waves produced in a surf zone behind the front of each breaking swell. They probably represent solutions to the Korteweg deVries (cnoidal-wave) equation, and their generation is favored by bottom topography not typical of most surf zones. 相似文献
89.
Fingerprinting glacial silt in last glacial-age sediments from Upper Klamath Lake (UKL) and Bear Lake (BL) provides continuous radiocarbon-dated records of glaciation for the southeastern Cascade Range and northwestern Uinta Mountains, respectively. Comparing of these records to cosmogenic exposure ages from moraines suggests that variations in glacial flour largely reflect glacial extent. The two areas are at similar latitudes and yield similar records of glacial growth and recession, even though UKL lies less than 200 km from the ocean and BL is in the continental interior. As sea level began to fall prior to the global Last Glacial Maximum (LGM), existing glaciers in the UKL area expanded. Near the beginning of the global LGM (26.5 ka), the BL record indicates onset of glaciation and UKL-area glaciers underwent further expansion. Both records indicate that local glaciers reached their maximum extents near the end of the global LGM, remained near their maxima for ~ 1000 yr, and underwent two stages of retreat separated by a short period of expansion. 相似文献
90.