Geochronology 

Calcite is frequently formed during alteration processes in the basaltic, uppermost layer of juvenile oceanic crust. Weathered oceanic basalts are hard to date with conventional radiometric methods. We show in a case study from the North Pamir, Central Asia, that calcite U-Pb age data – supported by geochemistry and petrological microscopy – has the potential to date sufficiently old oceanic basalts, if the time span between basalt extrusion and latest calcite precipitation (~ 25 Ma) is considered.

This paper outlines a method that helps mineral explore for gold. When can see the alteration caused by the mineralising fluids, it is possible to use geochemical methods to vector towards the deposit. But such methods failed at Martabe. We decided to work out why. Our results showed that there were several distinct and separate very short-lived alteration events. The answer might be that vectoring is possible only when samples are compared from the same mineralising system.

This study presents erosion rates of the George River and seven of its tributaries in northeast Tasmania, Australia. These erosion rates are the first measures of landscape change over millennial timescales for Tasmania. We demonstrate that erosion is closely linked to a topographic rainfall gradient across George River. Our findings may be useful for efforts to restore ecological health to Georges Bay by determining a pre-disturbance level of erosion and sediment delivery to this estuary.

We develop in-situ produced terrestrial cosmogenic krypton as a new tool to date and quantify Earth surface processes; the motivation being the availability of six stable and one radioactive isotope (⁸¹Kr, half-life 229 kyr) and of an extremely weathering-resistant target mineral (zircon). We provide proof of principle that terrestrial Kr_it can be quantified and used to unravel Earth surface processes.

Phanerozoic sedimentary rocks of northern Canada have compositionally heterogeneous detrital apatite with high age dispersion caused by differential thermal annealing. Discrete AFT kinetic populations with variable annealing temperatures are defined using elemental data but are poorly resolved using conventional parameters (D_par and Cl). Inverse thermal modelling of samples from northern Yukon reveals a complicated record of multiple heating-cooling cycles consistent with geological constraints.