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At the St Asaph Bypass, surface cracking developed along the crest of a modern highway cutting, above a cluster of badger setts excavated in the sandy soils of the cutting slope. This prompted concerns about the extent of the underlying tunnel systems and the possible existence of deep cavities lacking surface expression that might cause a potential slope instability problem. The full threat posed to the integrity of the cutting and to the safety of road users remained uncertain. In addition, intrusive investigations were deemed inappropriate and a non-invasive solution to the problem was required. Ground-penetrating radar was used along a 50 m stretch of the cutting to determine the full extent of the badger setts beneath the surface. The geophysical survey identified 324 m of tunnels and demonstrated that the tunnel network was generally shallow ( c. 0–2 m). Pronounced radar reflections characteristic of air voids were identified in the data and interpreted as the badgers’ access tunnels and living and nursery chambers whereas the more subdued features were interpreted as collapsed and abandoned diggings. This case history illustrates the benefits of using ground-penetrating radar to provide an understanding of slope stability and local ground conditions in areas of environmental sensitivity when non-intrusive investigations are required to provide reassurances in relation to public safety.

Two principal types of nephrite jade orebody are now recognized: (1) ortho-nephrite jade bodies associated with serpentinized ultrabasic igneous rocks and exemplified by those of the Canadian Cordillera, British Columbia; and (2) para-nephrite jade bodies associated with metasedimentary strata and exemplified by those of Eyre Peninsula, South Australia. Major-element geochemistry of nephrite jades from the two contrasting geological environments have much in common. However, trace-element geochemical signatures show marked dissimilarity with ortho-nephrites distinguished by high levels of the basic elements Cr, Co and Ni, and para-nephrites characterized by relatively subdued trace-element abundances. Whereas ortho-nephrite jade forms in folded orogenic belts and bears a mantle signature, para-nephrite jade may appear in a variety of tectonic settings but carries a crustal signature. The role of tectonic setting is important but subordinate to that of the composition of the source region in determining the typology of nephrite jades.

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Loess deposits in Asia have been used as indicators of palaeoclimate, because they are usually found bordering deserts. This paper reports extensive and thick deposits of loess in tropical southwest China, between latitudes 18 and 23°30′N, which is 1300 km south of known, and extensively researched loess deposits in north China. The present climate of the reported loess areas is hot and humid, with mean annual rainfall of 1000–2000 mm, and vegetation of subtropical evergreen broadleaf forest. This compares with less than 400 mm rainfall and vegetation of semi‐desert steppe, in areas of current loess accumulation on desert margins in north China. The source area of the loess, which is dated by optical luminescence to the late Pleistocene, from 90–222 ka, is thought to be the exposed East Asian Shelf, which was up to 140 m below present sea level during Quaternary arid phases. Recent research on the nature of the shelf environment, and the relatively large particle size of the loess, suggests a local origin. The reported loess is not interbedded with palaeosols, and small amounts of soil cover the loess, compared with well developed soils in loess in semiarid regions in north China. This is explained by elimination of the supply source by sea level rise following each arid phase, as continued dust supply appears necessary for soil to form. This preliminary report of loess in southwest China conflicts with palynological evidence, and suggests that recent reconstructions of Pleistocene aridity in east Asia may be conservative.