Title Information
Title
Abstract of Climate Change on Mars: The Nature and History of Non-Polar Ice-Rich Deposits, by Seth Kadish, Ph.D., Brown University, May 2011.
Name: Personal
Name Part
Kadish, Seth J
Role
Role Term: Text
creator
Origin Information
Copyright Date
2011
Physical Description
Extent
xviii, 288 p.
digitalOrigin
born digital
Note
Thesis (Ph.D. -- Brown University (2011)
Name: Personal
Name Part
Head, James
Role
Role Term: Text
Director
Name: Personal
Name Part
Mustard, John
Role
Role Term: Text
Reader
Name: Personal
Name Part
Huang, Yongsong
Role
Role Term: Text
Reader
Name: Personal
Name Part
Herbert, Timothy
Role
Role Term: Text
Reader
Name: Personal
Name Part
Fastook, James
Role
Role Term: Text
Reader
Name: Corporate
Name Part
Brown University. Geological Sciences
Role
Role Term: Text
sponsor
Genre (aat)
theses
Abstract
This dissertation explores the recent history of non-polar ice-rich paleodeposits on Mars, primarily through the analysis of pedestal craters. Pedestal craters are defined by having a crater bowl perched near the center of a plateau that is surrounded by a marginal outward-facing scarp. This work documents significant evidence that they result from impacts into ice-rich material deposited at mid latitudes during periods of climate change resulting from excursions to higher obliquity. The impact armors the proximal surface. When the obliquity lowers, the icy substrate sublimates and deflates from the intercrater terrain, but it is preserved beneath the indurated pedestal surfaces. Chapter one details the evidence for a climate-related formation mechanism, including the latitude-dependent distribution of pedestal craters, which form poleward of ~35�, their circular planform, and the presence of sublimation pits located on the marginal scarps of some pedestals. Chapter two investigates a high-latitude subsample of the pedestal crater population that exhibits layers along the craters� scarps, including one on the south polar layered deposit. These provide evidence that pedestal craters are capable of preserving layered ice-rich material. Chapter three extrapolates implications about the thicknesses of ice-rich deposits on the basis of the heights of pedestal craters, outlining the geographic regions in which pedestals are particularly tall. The presence of pedestals that are superposed or draped on other pedestals provides evidence that the formation process is recurring. Chapter four considers two other crater morphologies: excess ejecta craters and perched craters. Through a geographic, age, and physical comparison, the morphologies are shown to be genetically related to pedestal craters, resulting from impacts into similar ice-rich substrates. Chapter five discusses the periodicity and pathways that ice-rich material may take from the poles to the mid and low latitudes. Data for the emplacement duration and recurrence of ice-rich material are placed in the context of climate model predictions. This yields a possible obliquity history for the past 200 Myr on Mars, and leads to the identification of significant climatic shifts.
Subject
Topic
Mars
Subject
Topic
Climate
Subject
Topic
Craters
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/864281")
Topic
Climatology
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/966505")
Topic
Ice
Subject (FAST) (authorityURI="http://id.worldcat.org/fast", valueURI="http://id.worldcat.org/fast/1243063")
Geographic
Mars (Planet)
Record Information
Record Content Source (marcorg)
RPB
Record Creation Date (encoding="iso8601")
20111003
Language
Language Term: Code (ISO639-2B)
eng
Language Term: Text
English
Identifier: DOI
10.7301/Z09S1P9G
Access Condition: rights statement (href="http://rightsstatements.org/vocab/InC/1.0/")
In Copyright
Access Condition: restriction on access
Collection is open for research.
Type of Resource (primo)
dissertations