Ice-crystal traces imply ephemeral freezing in early Permian equatorial Pangea

Ice Crystal Growth during the Rapid Freezing of Tissues

This paper contains a few comments on the physical analysis of the factors controlling the rate of cooling, and the relation of the rate of cooling to ice crystal formation which has been carried out in connection with the electron microscopic work described by Dr. C-ersh at this conference. Of the many factors which influence the rate of cooling, by far the most important is the size of the sa...

Freezing Properties of Disaccharide Solutions: Inhibition of Hexagonal Ice Crystal Growth and Formation of Cubic Ice

Shifts in late Paleozoic atmospheric circulation over western equatorial Pangea: Insights from pedogenic mineral d18O compositions

The d18O values of pedogenic calcites, phyllosilicates, and iron (oxyhydr)oxides from fossil soils throughout the southwestern United States show systematic paleolatitudinal and temporal trends that indicate a significant change in soil moisture conditions and atmospheric circulation patterns over southwestern Euramerica throughout latest Pennsylvanian and Early Permian time. A progressive depl...

Supernumerary ice-crystal halos?

Geometric-optics singularities in the intensity profiles of refraction halos formed by randomly oriented ice crystals are softened by diffraction and decorated with fine supernumerary fringes. If the crystals have a fixed symmetry axis (as in parhelia), the geometric singularity is a square-root divergence, as in the rainbow. However, the universal curve that describes diffraction is different ...

The so-called “Paleophytic–Mesophytic” transition in equatorial Pangea — Multiple biomes and vegetational tracking of climate change through geological time

Article history: The Paleophytic, Mesophyti Accepted 26 March 2008