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11.
Landslides - A Correction to this paper has been published: https://doi.org/10.1007/s10346-021-01646-0. 相似文献
12.
Landslides - Assessment of the spatial probability of future landslide occurrences for disaster risk reduction is done through landslide susceptibility modelling. In this study, we investigated the... 相似文献
13.
Martha Tapas Ranjan Roy Priyom Jain Nirmala Khanna Kirti Mrinalni K. Kumar K. Vinod Rao P. V. N. 《Landslides》2021,18(6):2125-2141
Landslides - India ranks first in the world in terms of fatal landslides. Large vulnerable area (0.42 million km2), high population density and monsoon rainfall make India’s landslide... 相似文献
14.
Numerical study of baroclinic tides in Luzon Strait 总被引:6,自引:1,他引:5
The spatial and temporal variations of baroclinic tides in the Luzon Strait (LS) are investigated using a three-dimensional
tide model driven by four principal constituents, O1, K1, M2 and S2, individually or together with seasonal mean summer or winter stratifications as the initial field. Barotropic tides propagate
predominantly westward from the Pacific Ocean, impinge on two prominent north-south running submarine ridges in LS, and generate
strong baroclinic tides propagating into both the South China Sea (SCS) and the Pacific Ocean. Strong baroclinic tides, ∼19
GW for diurnal tides and ∼11 GW for semidiurnal tides, are excited on both the east ridge (70%) and the west ridge (30%).
The barotropic to baroclinic energy conversion rate reaches 30% for diurnal tides and ∼20% for semidiurnal tides. Diurnal
(O1 and K1) and semidiurnal (M2) baroclinic tides have a comparable depth-integrated energy flux 10–20 kW m−1 emanating from the LS into the SCS and the Pacific basin. The spring-neap averaged, meridionally integrated baroclinic tidal
energy flux is ∼7 GW into the SCS and ∼6 GW into the Pacific Ocean, representing one of the strongest baroclinic tidal energy
flux regimes in the World Ocean. About 18 GW of baroclinic tidal energy, ∼50% of that generated in the LS, is lost locally,
which is more than five times that estimated in the vicinity of the Hawaiian ridge. The strong westward-propagating semidiurnal
baroclinic tidal energy flux is likely the energy source for the large-amplitude nonlinear internal waves found in the SCS.
The baroclinic tidal energy generation, energy fluxes, and energy dissipation rates in the spring tide are about five times
those in the neap tide; while there is no significant seasonal variation of energetics, but the propagation speed of baroclinic
tide is about 10% faster in summer than in winter. Within the LS, the average turbulence kinetic energy dissipation rate is
O(10−7) W kg− 1 and the turbulence diffusivity is O(10−3) m2s−1, a factor of 100 greater than those in the typical open ocean. This strong turbulence mixing induced by the baroclinic tidal
energy dissipation exists in the main path of the Kuroshio and is important in mixing the Pacific Ocean, Kuroshio, and the
SCS waters. 相似文献
15.
Natural Resources Research - The original version of this article unfortunately contained a mistake in figures. The source file for figures was submitted and published incorrectly; hence, the... 相似文献
16.
With oblique rifting, both extension perpendicular to the rift trend and shear parallel to the rift trend contribute to rift formation. The relative amounts of extension and shear depend on α, the acute angle between the rift trend and the relative displacement direction between opposite sides of the rift. Analytical and experimental (clay) models of combined extension and left-lateral shear suggest the fault patterns produced by oblique rifting. If α is less than 30°, conjugate sets of steeply dipping strike-slip faults form in rifts. Sinistral and dextral strike-slip faults trend subparallel and at large angles to the rift trend, respectively. If α is about 30°, strike-slip, oblique-slip and/or normal faults form in rifts. Faults with sinistral and dextral strike slip trend subparallel and at large angles to the rift trend, respectively. Normal faults strike about 30° counterclockwise from the rift trend. If α exceeds 30°, normal faults form in rifts. They have moderate dips and generally strike obliquely to the rift trend and to the relative displacement direction between opposite sides of the rift. If α equals 90°, the normal faults strike parallel to the rift trend and perpendicularly to the displacement direction.The modeling results apply to the Gulf of California and Gulf of Aden, two Tertiary continental rift systems produced by combined extension and shear. Our results explain the presence and trends of oblique-slip and strike-slip faults along the margins of the Gulf of California and the oblique trend (relative to the rift trend) of many normal faults along the margins of both the Gulf of California and the Gulf of Aden. 相似文献
17.
We report broadband infrared photometry of comets P/Stephan-Oterma and Bowell between 1 and 20 μm. Their JHK colors are similar to P/Meier and P/Tuttle and are compatible with scattering of sunlight by micron-sized grains. The thermal emission from P/Stephan-Oterma showed an effective temperature significantly higher than that expected from a blackbody in equilibrium. The thermal emission can be models be fit by models of the dust coma consisting of micron-sized grains. Most of the flux at all observed wavelengths comes from the dust grains rather than form the nucleus. 相似文献
18.
We consider the inverse problem of permeability estimation for two-phase porous-media flow. The novel approach is based on
regularization by zonation, where the geometry and size of the regions are chosen adaptively during the optimization procedure.
To achieve this, we have utilized level-set functions to represent the permeability. The available data are sparsely distributed
in space; hence, it is reasonable to confine the estimation to coarse-scale structures. The level-set approach is able to
alter the boundaries between regions of different permeability without strict restrictions on their shape; however, when the
data are sparse, a reasonable initial guess for the permeability is required. For this task, we use adaptive multiscale permeability
estimation, which has the potential of identifying main permeability variations. These are described by a piecewise constant
function, where the constant values are attained on rectangular zones. In the current work, we develop a level-set corrector
strategy, assuming adaptive multiscale permeability estimation as a predictor. 相似文献
19.
Luiz N. da Costa Adi Nusser Wolfram Freudling Riccardo Giovanelli Martha P. Haynes John J. Salzer & Gary Wegner 《Monthly notices of the Royal Astronomical Society》1998,299(2):425-432
We present a comparison between the peculiar velocity fields measured from a recently completed l -band Tully–Fisher survey of field spirals (SFI) and that derived from the IRAS 1.2-Jy redshift survey galaxy distribution. The analysis is based on the expansion of these data in redshift space using smooth orthonormal functions, and is performed using low- and high-resolution expansions, with an effective smoothing scale which increases almost linearly with redshift. The effective smoothing scales at 3000 km s−1 are 1500 and 1000 km s−1 for the low- and high-resolution filters. The agreement between the high- and low-resolution SFI velocity maps is excellent. The general features in the filtered SFI and IRAS velocity fields agree remarkably well within 6000 km s−1 . This good agreement between the fields allows us to determine the parameter β = Ω0.6 / b , where Ω is the cosmological density parameter, and b is the linear biasing factor. From a likelihood analysis on the SFI and IRAS modes we find that β = 0.6 ± 0.1, independently of the resolution of the modal expansion. For this value of β, the residual fields for the two filters show no systematic variations within 6000 km s−1 . Most remarkable is the lack of any coherent, redshift-dependent dipole flow in the residual field. 相似文献
20.
Martha Riherd Weller Marian Furst T.A. Tombrello D.S. Burnett 《Geochimica et cosmochimica acta》1978,42(7):999-1009
We have analyzed B in carbonaceous chondrites in order to clarify a factor of 100 difference between the solar system B abundance derived from the solar photosphere and that inferred from previous meteorite data. Consistent results were obtained from two instrumental methods for B analysis: (a) counting of the high energy betas from 12B produced by the 11B(d,p) reaction, and (b) measurement of particle track densities from 10B(n,α)7Li in a plastic track detector affixed to a homogenized meteorite sample. Contamination is a major problem in B analyses, but extensive testing showed that our results were not seriously affected. Our B concentrations are typically 1–2 ppm and are a factor of 2–6 lower than previous carbonaceous chondrite measurements. Our data for the Cl chondrites Ivuna and Orgueil would indicate a solar system B/Si atomic abundance ratio of 58 × 10?6, but this is still a factor of 2–10 higher than the photospheric estimates. It may be that B is depleted in the sun by thermonuclear processes; however, the similarity of photospheric and meteoritic Be abundances is a problem for this point of view. Alternatively, B may be enhanced in carbonaceous chondrites, but this would make B a cosmochemically unique element. A mm-sized (Fe,Mn,Mg)CO3 crystal from Orgueil shows no B enrichment. We find 10B ≤ 1016 atoms/g in two Allende fine-grained inclusions suggesting that B is not a refractory element under solar nebula conditions. This 10B limit, when taken as a limit on 10Be when the inclusion formed, puts constraints on the possibility of a solar system synthesis of 26Al. For a proton spectrum of E?a, a must be ≥ 3 if a solar gas is irradiated or a ≥1.5 if dust of solar composition is irradiated. 相似文献