Investigations in Martian geology. Part 1:

مرکز و کتابخانه مطالعات اسلامی به زبان های اروپایی

منو

" Investigations in Martian geology. Part 1: "
J. M. Moore

Document Type	:	Latin Dissertation
Language of Document	:	English
Record Number	:	1112555
Doc. No	:	TLpq303796100
Main Entry	:	J. M. Moore
Title & Author	:	Investigations in Martian geology. Part 1:\ J. M. Moore
College	:	Arizona State University
Date	:	1990
student score	:	1990
Degree	:	Ph.D.
Page No	:	179
Abstract	:	This dissertation consists of two parts. Part I describes the geomorphology of a portion of northeastern Arabia, Mars. This surface is covered by an extensive, layered deposit which has been, in places, substantially eroded. Speculative origins for the deposit include formation as a differentially welded pyroclastic tuff, or a differentially compacted, zonally indurated aeolian dust deposit. Part II is an experimental study of the sublimation rate of H2O ice, both from clean surfaces and from under thin layers of dust or sand, in a Mars-like environment. The major conclusions drawn from the results of this experiment are: (1) even very thin layers of dust greatly lower the sublimation rate of an underlying ice substrate being heated from above, whereas thin layers of sand suppress the sublimation rate of underlying ice being heated from above to a significantly lesser extent; (2) thin layers of dust or sand only mildly suppress the sublimation rate of an underlying ice substrate when sample is wholly isothermal; (3) even a low-flux, desiccated gas flow over the sample surface significantly increases the sublimation rate of any given sample; (4) dry sublimation of ice underlying thin layers of dust or sand may modify the surface texture as a function of particle cohesion and as the ratio of particle layer thickness to the amount by which the surface was lowered; and (5) the actual sublimation rate of clean ice is several factors lower that the sublimation rate predicted by a commonly used formula.
Subject	:	Astronomy
	:	Astrophysics
	:	Astrophysics
	:	Earth sciences
	:	Geology
	:	Pure sciences