TEM, HRTEM - Acronyms for transmission-electron-microscope and high-resolution-transmission-electron-microscope. These are primarily imaging instruments that work for small samples which have been thinned to electron transparancy. Accelerated electrons pass through and interact with samples, allowing microstructural and crystallographic data to be obtained. HRTEM is done on a smaller, higher-magnification scale than TEM and can be used to image the lattice planes of minerals.
pH - This parameter (dimensionless) is a measure of hydrogen ion activity (effective H ion concentration) in a solution. pH = -log aH+, where aH+ = activity of hydrogen ion. Lower values (<7) of pH represent progressively acidic solutions, and higher values (>7) represent progressively more basic solutions.
Eh - This parameter (measured in volts) reflects the ability of a solution to be an electron donor or acceptor relative to a standard H2 electrode. Oxidizing solutions have Eh > 0 and function as electron acceptors; reducing have Eh < 0 and function as electron donors.
regolith gardening - This refers to the overturning
of a regolith by impact processes.
Vug (~1 mm across) filled with blue halite in Zag
(H-chondrite breccia). This halite probably formed
by evaporation of brines in the H-chondrite
parent body. See the accompanying link for a short
article by Zolensky et al.
From: http://www.nyrockman.com/meteorite/gallery/zag.htm
Transmitted light image of coarse halite in Monahans
(H-chondrite breccia); field of view ~ 1 mm wide. Water-filled
fluid inclusions can be seen within the halite. This halite
probably formed by evaporation of brines in the H-chondrite
parent body. See the accompanying link for a short article
by
Zolensky and coworkers.
From: http://www-curator.jsc.nasa.gov/astromaterials/specialfeatures/monahans/