14 research outputs found
Anthropogenic renourishment feedback on shorebirds: A multispecies Bayesian perspective
Anticonvulsant activity of melatonin against seizures induced by quinolinate, kainate, glutamate, NMDA, and pentylenetetrazole in mice
Diurnal changes in cyclic nucleotide response to pineal indoles in murine mammary glands
Presynaptic effects of melatonin on norepinephrine release and uptake in rat pineal gland
Paleo-Rock-Hosted Life on Earth and the Search on Mars: A Review and Strategy for Exploration
A randomized, double-blind study of six combined oral contraceptives
Contraception253231-241CCPT
Climatic variability and body size variation in the muskrats (Ondatra zibethicus) of North America
On the origin of A-tents (pop-ups), sheet structures, and associated forms
Copyright © 2009 by SAGE PublicationsA-tents are also known as pop-ups and by several other local names. They consist of raised slabs or plates of various thicknesses and origins. Laminae are caused by weathering, and spall plates or slabs may be caused in part by freeze-thaw acting on water held in pre-existing partings which are, however, like the sheet fractures that define the thicker sheet structures, probably of tectonic origin. A-tents are the result of the buckling of such laminae, plates and slabs. Again, tectonism in the form of compressive horizontal stress, appears the most likely and common causation, though decreases in lithostatic pressure consequent on unloading and, in particular cases, surficial expansion of plates caused by the intense heat of fires, may also contribute to rock failure and rupture. All A-tents are of Holocene age and are, therefore, neotectonic forms. Some have developed in living memory, and some are known to be developing from blisters. There is some evidence of continued dislocation along sheet fractures and of the transformation of blisters or arches into A-tents under the influence of continued lateral compression. This review demonstrates, therefore, that A-tents, sheet structures, and associated forms share a common heritage