Abstract Reconstructing variations in the intensity of chemical weathering in river basins is crucial if we are to understand how climate change impacts environment and whether there are feedbacks between climate and weathering processes. Quantifying chemical weathering is, however, a complicated process, involving a number of competing proxies. We compare weathering records from the Pearl River delta of southern China and Ocean Drilling Program (ODP) Sites 1144 and 1146 on the northeastern slope of the South China Sea in order to test which proxies are the most widely applicable and robust. Comparison with speleothem rainfall records indicates that K/Al tracks precipitation variations most closely and out-performs the widely used Chemical Index of Alteration (CIA). Correlation of K/Al and kaolinite/illite indicates that this clay ratio is also an effective proxy of weathering intensity across all sites and timescales. Kaolinite/smectite, and to a lesser extent smectite/(illite+chlorite), are also indicative of weathering intensity, but show more scatter between sites that may be linked to provenance effects. Mg/Al is relatively immune to grain-size effects, but does not correlate well with other proxies. K/Rb is a reasonably reliable indicator of chemical weathering intensity and may be more sensitive than CIA or K/Al to weathering changes over short timescales and when weathering is not too intense. 87 Sr/ 86 Sr can be useful but can be influenced by both grain size and provenance effects. In general marine archives of fluvial sediment may record variations in weathering linked to climate, but these are increasingly signals of reworking going further offshore.

Abstract This paper examines the Late Quaternary evolutionary history of the northern coast of the South China Sea by reviewing geological evidence from this coast. Results show that: (1) a lithostratigraphy with two marine sequences is observed in the deltaic basins of the Song Hong, Pearl and Han rivers, and these basins are all bounded by active faults; (2) whilst the upper marine sequence belongs to the present interglacial or the past 10.5 ka, the lower or older marine sequence was most likely deposited during the high sea level of the last interglacial period, c. 126–120 ka; (3) the burial depth of the older marine sequence is recorded at −15 m below modern sea level or deeper, implying localized subsidence of varying rates between these deltaic basins because the height of sea level during the last interglacial was close to that of the present; (4) this tectonic process is probably associated with the continuous long-term subsidence of the northern South China Sea continental shelf within the tectonic framework of southward continental extension of the Eurasian Plate during the Cenozoic; (5) fault activity has enhanced the localized subsidence of these deltaic basins, which led to marine inundation during interglacial high sea levels.

Abstract During the TRANSALP project, deep seismic surveys and accompanying geophysical and geological projects were carried out to better understand the deep structure of the Eastern Alps south of Munich. The TRANSALP field trip series roughly follows the route in three parts: the Tauern Window, the Northern Calcareous Alps and its foreland, and the Southern Alps including the Dolomites. In this Tauern Window field trip, we will visit most of the geologically important sites along the middle part of the traverse or in its vicinity. The main topics covered in the Tauern Window will be the early Alpine paleogeographic situation on an extending European continental margin, Alpine nappe stacking and ductile rock deformation, metamorphism, uplift modes and exhumation, lateral escape, and the Brenner normal fault.