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Abstract: A robust geochronology based on U–Pb zircon ages in Australia (n=158) and Europe (n=376) provides a rigorous test of (1) the model of a climatic–tectonic cycle of a single continent (Pangea) and ocean (Panthalassa) with an icehouse climate alternating with many continents and oceans with a greenhouse climate, and (2) the idea of coeval (320 to 300Ma) right-lateral shear events in Eastern Australia and Europe followed by earliest Permian (~300Ma) extension. During Pangean assembly, stress from the oblique collision of Laurussia and Gondwanaland bent the oroclines in Iberia, drove the intense shortening in Central Australia and terminal megakinking in the Lachlan orogen, and possibly drove the bending of oroclines in Eastern Australia. Extension I (~300Ma, Carboniferous/Permian) followed the first outburst of self-induced (monsoonal) heat from the newly assembled Pangea, and generated fresh accommodation space for globally synchronous sedimentary successions, including the glacial base and succeeding coals of the Gondwana facies. Extension was relieved by sags on (isotropic) cratons and rifts on (anisotropic) fold belts with voluminous volcanics. In Europe, the Variscan orogen was cut into right-lateral magmatic rifts and the craton sagged to accumulate magmatic basins; likewise, the convergent margin of Eastern Australia was cut into a long magmatic rift and the cratonic foreland covered by the Gondwana facies. The end-Permian (251Ma) sea-level drawdown, climate warming, and severe biotic extinction, with no obvious tectonic cause, were responsible for the Early-Middle Triassic coal gap. A second outburst of heat drove Extension II (235Ma, Carnian, Late Triassic), expressed as rifts and sags that accumulated a second set of coal-bearing strata. At this time of its largest extent, Pangea underwent incipient breakup by rifting of the Atlantic Margins of North America, Morocco, and Western Europe that developed into 190Ma drifting. [Copyright &y& Elsevier]

Abstract: It is practically impossible to measure soil properties continuously at each location across the globe. Therefore, it is necessary to have robust systems that can predict soil properties at a given location. That is needed in many tropical countries where the dearth of soil property measurements is large. This paper reviews the use of pedotransfer functions (PTF) for predicting properties of soils in the tropics. First, the guiding principles of prediction and the type of predictors are discussed, including laboratory data, field description and soil morphology, electromagnetic spectrum, proximal and remote sensed data. In the subsequent section, PTFs are discussed for soil physical and chemical properties followed by infrared spectroscopy, proximal sensing and remote sensing. An analysis of ISRIC (mainly tropical) and USDA (mainly temperate) soil databases showed that soils in the tropics have higher clay content, lower cation exchange capacity, higher bulk density, lower water content at −10kPa and −1500kPa than soils in the temperate regions. Various methods developed in temperate regions can be applied for the soils in the tropical regions although calibration and careful selection of predictors remains necessary. It is concluded that PTFs are an important tool to overcome the dearth of soil data in many tropical countries. [Copyright &y& Elsevier]