[1] The lunar steep-sided Gruithuisen and Mairan domes are morphologically and spectrally distinctive structures and appear similar to terrestrial extrusive volcanic features characterized by viscous magma. We use the basic morphologic and morphometric characteristics of the domes to estimate the yield strengths ( 10 Pa), plastic viscosities ( 10 Pa s), and effusion rates ( 50 m/s) of the magma...

Exceptional exposures of igneous intrusions of the Henry Mountains of southern Utah allow for the detailed study of three-dimensional pluton geometries as well as igneous emplacement and assembly processes. Examination of the geometry, fabric, and wallrock structures of relatively small intrusions (<3 km map-view diameter) suggests that several plutons in the region (Maiden Creek sill, Trachyte...

Galileo and Clementine multispectral data of the Mare Tranquillitatis region have been analyzed to investigate the stratigraphy of basaltic units and the effects of lateral and vertical mixing processes within the mare. The distribution of compositionally distinct mare units is observed to be correlated with previous UV/VIS ratio images, although estimates of soil titanium contents are low in s...

Observations on shocked quartz in Cretaceous-Tertiary (K-T) boundary sediments compellingly tied to Chicxulub crater raise three problems. First, in North America shocked quartz occurs above the main K-T ejecta layer. Second, shocked quartz is more abundant west than east of Chicxulub. Third, shocked quartz reached distances requiring initial velocities up to 8 kilometers per second, correspond...

The Bushveld Complex formed by the crystallization of successive basaltic magmatism may be of the order of several million years. For example, the Columbia River Basalts (Hooper, injections of magma, which were sufficiently closely spaced in time that each previous magma had not cooled and differentiated 1988) were erupted in the period 17–12 Ma, with minor eruptions for a further 5 my, althoug...

Experiments were made to determine the effects of sediment size, sediment concentration, and flow velocity on the depositional style of sand-sized particles in a highvelocity surgd. A dimdnsional analysis of the experimental system was performed in an effort to relate the experimental results to deposits from turbidity currents and overwash surges. A large part of each deposit was a result of d...

Intrusions of magma induce thermal aureoles in the country rock. Analytical solutions predict that the thickness of an aureole is proportional to the thickness of the intrusion. However, in the field, thermal aureoles are often significantly thinner or wider than predicted by simple thermal models. Numerical models show that thermal aureoles are wider if the heat transfer in the magma is faster...