We carry out Monte Carlo simulations and study the dependence of the behaviors of steps on impurities on a vicinal face. We assume that the impurities are immobile and the lifetime of them is much longer than that of adatoms. During growth, the impurities in front of a step prevent the step from advancing. If a wide terrace appears due to the fluctuations of step positions, the number of impuri...

The ;400 km2 Clearwater River basin, located on the Pacific flank of the actively uplifting Olympic Mountains of western Washington State, contains a well-preserved flight of Holocene fluvial terraces. We have collected a large data set of numeric ages from these terraces that is used to elucidate the geomorphic, fluvial, active tectonic, and climatic processes that operate at Holocene spatial ...

New, high-precision U-series ages of solitary corals (Balanophyllia elegans) coupled with molluscan faunal data from marine terraces on the Pacific Coast of North America yield information about the timing and warmth of the last interglacial sea-level highstand. Balanophyllia elegans takes up U in isotopic equilibrium with seawater during growth and shortly after death. Corals from the second t...

A suite of fluvial terraces (T1–T6, from top to bottom of the staircase) occur along a 70 km stretch of the Tejo River in central Portugal, between the small towns of Gavião and Chamusca. Terrace correlation was based upon the following: (a) aerial photograph analysis, geomorphological mapping and field topographic survey; (b) sedimentology of the terrace deposits, namely the maximum particle s...

As part of a study of species important in automotive exhaust chemistry, the reactivity of atomic N and NO on Pt~335! at low temperature has been studied. The atomic N was produced by dissociating adsorbed NO with a 76 eV electron beam. Cross sections for electron-stimulated desorption and dissociation are estimated for NO on terrace and step sites. Terrace NO is at least five times more likely...

Combining high resolution optical microscopy and spectroscopy, we propose a novel, generally applicable and highly sensitive method for determining the local morphology in organic semiconductor thin films (e.g. perfluoropentacene (PFP)). An azimuthally or radially polarized doughnut mode (APDM or RPDM) laser beam is focused by a high numerical aperture parabolic-mirror to excite a diffraction l...

[1] The landscape response to climate change is frequently investigated with models because natural experiments on geologic timescales are rare. In Quebrada Veladera, in the western Andes Mountains, the formation of alluvial terraces during periods of high precipitation presents opportunities for such an experiment. We compare drainage-average erosion rates during Pleistocene terrace deposition...

This paper presents first results from scanning tunneling microscopy measurements, which show that a close-packed terrace of a metal surface can be far from static, even at temperatures as low as room temperature. We make the motion visible of the atoms in a Cu(001) terrace, by embedding a low density of In atoms in the first Cu layer. The peculiar characteristics of the motion of the In show t...

The nucleation of graphene on a transition metal surface, either on a terrace or near a step edge, is systematically explored using density functional theory calculations and applying the two-dimensional (2D) crystal nucleation theory. Careful optimization of the supported carbon clusters, C(N) (with size N ranging from 1 to 24), on the Ni(111) surface indicates a ground state structure transfo...

Previous studies reported that the 2015 Gorkha earthquake (Mw 7.8), which occurred in Nepal, triggered landslides in mountainous areas. In Kathmandu, earthquake-induced land subsidence was identified by interpreting local phase changes in interferograms produced from Advanced Land Observing Satellite-2/Phased Array type L-band Synthetic Aperture Radar-2 data. However, the associated ground defo...