Show simple item record

dc.contributor.advisorKocurek, Gary
dc.creatorBrothers, Sarah Christian
dc.date.accessioned2017-04-10T13:47:05Z
dc.date.available2017-04-10T13:47:05Z
dc.date.issued2016-12
dc.date.submittedDecember 2016
dc.identifierdoi:10.15781/T28K7524Z
dc.identifier.urihttp://hdl.handle.net/2152/46365
dc.description.abstractDunes and dune fields are dynamic features that respond to the unique boundary conditions under which they evolve by changing migration habits, types and frequencies of interactions, and morphologies. As such, dunes convey information about changing atmospheric and surface conditions on planetary bodies including Earth, Mars, Venus, and Titan, and the stratigraphic record left by these bedforms is used to interpret the evolution of paleoclimate and surface environments. In four parts this work examines how the dynamics of individual dunes, dune fields, and aeolian systems influence stratigraphic architectures across multiple spatial scales. At White Sands Dune Field, New Mexico, the decadal histories of defect and bedform repulsion-type interactions are traced through a time-series of images. The resultant stratigraphic architectures are derived from plan-view exposures and ground penetrating radar sensing of dune interiors. This is the first documentation of the unique stratigraphic architectures that result from interactions between dunes. Within Chasma Boreale, Planum Boreum, Mars, boundary conditions controlling the discrete geomorphic expressions of the Hyperboreae Undae dune fields are evaluated using morphologic distributions. The distributions reveal that dune field expressions change over short horizontal scales and are dependent upon wind regime and sediment state, which operate under the background condition of dune induration by ice. Hyperboreae Undae form only part of the Chasma Boreale sediment system, however. Perennial layered ice deposits also are present on the floor of the reentrant. The changing balance of ice- and sand-dominated processes in space and time have resulted in an accumulation that transitions between ancient aeolian cavi unit-style accumulation and modern layered ice deposit-style accumulation. These accumulations can be interpreted through aeolian sequence stratigraphy. Findings from the Chasma Boreale transitional sediment system are applied to nearby outcrops of a transitional section of ancient cavi unit, which formed in an environment analogous to the modern Chasma Boreale sediment system. A sequence interpretation of the transitional cavi unit stratigraphic succession demonstrates how the aeolian system transitioned into overlying water ice deposits without a gap in the geologic record, verifying that the cavi unit and NPLD should be unified under a sequence stratigraphic framework.
dc.format.mimetypeapplication/pdf
dc.language.isoen
dc.subjectDunes
dc.subjectStratigraphy
dc.subjectWhite Sands Dune Field
dc.subjectNew Mexico
dc.subjectDune dynamics
dc.subjectDune interactions
dc.subjectMars
dc.subjectPlanum Boreum
dc.subjectCavi unit
dc.subjectAeolian sequence stratigraphy
dc.titleAeolian dune dynamics and the stratigraphic record
dc.typeThesis
dc.date.updated2017-04-10T13:47:05Z
dc.contributor.committeeMemberByrne, Shane
dc.contributor.committeeMemberHern, Caroline
dc.contributor.committeeMemberHolt, John
dc.contributor.committeeMemberMohrig, David
dc.description.departmentGeological Sciences
thesis.degree.departmentGeological Sciences
thesis.degree.disciplineGeological Sciences
thesis.degree.grantorThe University of Texas at Austin
thesis.degree.levelDoctoral
thesis.degree.nameDoctor of Philosophy
dc.type.materialtext


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record