The most-cited works in Geomorphology

We conducted a review and analysis of the references cited in articles published (1995–2004) in the journal Geomorphology and also solicited comments from the authors of the most-cited works on their major influences. Of the 31,696 unique works cited in the journal, only 22 were referenced at least 20 times, with the vast majority (92%) cited only once or twice. We divided the citations into the 10 most-cited books (i.e., complete volumes) and 10 most-cited papers (i.e., journal articles, book chapters, reports). A total of 23 different researchers were responsible for the 20 works, with one (Wolman) being an author or co-author of a quarter of them. Seven of the ten most-cited papers were based on work in the USGS in the mid-twentieth century, indicating a particularly fruitful time of geomorphic research and a particularly important cohort of scientists. Based on our citation analysis and author commentaries, we suggest that classic works in geomorphology are most likely to be those that provide useful knowledge and those that incorporate interdisciplinary perspectives.     

Gamma-ray bursts and Swift

Now that the Swift satellite is up and running, Paul O'Brien, Julian Osborne and Keith Mason report on the ideas and observations that this fast-moving autonomous observatory is investigating.     

Earthquake-induced landslides in Central America

Central America is a region of high seismic activity and the impact of destructive earthquakes is often aggravated by the triggering of landslides. Data are presented for earthquake-triggered landslides in the region and their characteristics are compared with global relationships between the area of landsliding and earthquake magnitude. We find that the areas affected by landslides are similar to other parts of the world but in certain parts of Central America, the numbers of slides are disproportionate for the size of the earthquakes. We also find that there are important differences between the characteristics of landslides in different parts of the Central American isthmus, soil falls and slides in steep slopes in volcanic soils predominate in Guatemala and El Salvador, whereas extensive translational slides in lateritic soils on large slopes are the principal hazard in Costa Rica and Panama. Methods for assessing landslide hazards, considering both rainfall and earthquakes as triggering mechanisms, developed in Costa Rica appear not to be suitable for direct application in the northern countries of the isthmus, for which modified approaches are required.     

Assessment of temporal changes in coastal sand dune environments using the log-hyperbolic grain-size method

Abstract Three cores (<9 m long) recovered from late Holocene coastal sand dunes in Northumberland, north‐eastern England, were examined stratigraphically and dated by the infrared stimulated luminescence (IRSL) method to the time period between the Medieval Warm Period (MWP; ≈ 900–1200 AD) and Little Ice Age (LIA; ≈ 1550–1800 AD). Grain‐size variability and CaCO₃ content were determined at 10‐mm intervals throughout parts of the cores. The sahara computer program was used to plot the log‐hyperbolic distribution (LHD) of grain‐size spectra from different stratigraphic levels and estimate the LHD's statistical components. Core samples plot variously in the depositional and erosional domains of the hyperbolic chi (χ) vs. xi (ξ) shape triangle, which describes components of sediment sorting. Depositional and erosional phases, discriminated within the LHD's shape triangle, cannot readily be resolved from core stratigraphies or correlated between cores. IRSL dates from single cores show a clustering about the period 1430–1540. Between the dated horizons, dunes accreted at ≈ 0·02–0·05 m year^?1, enabling the timing of excursions in χ and ξ to be estimated. These excursions, which can be resolved to the subannual level between the dated horizons, may be related to deposition by episodic storms or storm surges in the North Sea region, which is supported by historical documentary evidence. This innovative use of the LHD method and its derived statistics can be used successfully to describe temporal trends in coastal depositional environments and identify likely storm events in dune sediment records.     

Multi-attribute machine learning analysis for weak BSR detection in the Pegasus Basin,Offshore New Zealand

Marine Geophysical Research - Much of our knowledge of gas hydrate in the Dongsha area of the South China Sea has been gained through intensive geophysical surveys and drilling. However, many...     

The effect of salinity on growth and weight loss of juvenile plaice (Pleuronectes platessa, L): An experimental test

Previous population estimates of the 0+ plaice (Pleuronectes platessa L.) in the Firth of Forth, east central Scotland, did not take account of the Forth estuary west of the Forth bridges. Previous work found plaice in the estuary grew as fast as, or faster than, the outer firth plaice. It was hypothesised that salinity may affect growth rates of early 0+ plaice. This hypothesis was tested in a laboratory experiment, by exposing juvenile plaice to three different, but naturally — experienced by the juveniles, salinities; 25, 30 and 35. Plaice fed a minimum ration did not grow in length. Mean weight decreased at all three salinities, however, the lowest weight loss was found at the lowest salinity (25) and the highest weight loss was found at the highest salinity (35). The minimum feeding ration was halted and plaice were then fed ad libitum. Consumption rates were not significantly different during the ad libitum feeding, while significant differences in mean weight change were found between the highest and lowest salinities.     

FAUST observations of ultraviolet sources in the directions of NGC 4038–39 and 6752

Analysis of ultraviolet (UV) observations with the FAUST shuttle-borne telescope toward the Antennae and NGC 6752 celestial regions resulted in the detection of 46 and 221 candidate sources respectively, for a signal-to-noise ratio of 8. We discuss the source detection process and the identification of UV sources with optical counterparts. Using correlations with existing catalogues, we present reliable identifications for approximately 60 per cent of the sources. We find that most identified objects are B, A and F stars. The remaining identified objects are galaxies, a white dwarf in a binary system, and two K-type stars. Nearly all of the remaining unidentified objects have assigned optical counterparts but, lacking additional information, we give these only as best estimates. With help from new diagnostic diagrams, we suggest that these unclassified objects are main-sequence (or giant) stars within the local spiral arm or halo; or other hot evolved objects within the local spiral arm. We discuss the nature of the objects found and compare our results with those predicted from spectral and Galactic models.