ERA

Download the full-sized PDF of Evolution of Erosional Unconformities in the Cenozoic Succession of the Cayman IslandsDownload the full-sized PDF

Analytics

Share

Permanent link (DOI): https://doi.org/10.7939/R3N58CV08

Download

Export to: EndNote  |  Zotero  |  Mendeley

Communities

This file is in the following communities:

Graduate Studies and Research, Faculty of

Collections

This file is in the following collections:

Theses and Dissertations

Evolution of Erosional Unconformities in the Cenozoic Succession of the Cayman Islands Open Access

Descriptions

Other title
Subject/Keyword
Sinkhole-filling deposits
Unconformity
Karst
Type of item
Thesis
Degree grantor
University of Alberta
Author or creator
Liang, Ting
Supervisor and department
Jones, Brian (Earth and Atmospheric Sciences)
Examining committee member and department
Lowenstein, Tim (Geology, State University of New York)
Harris, Nicholas (Earth and Atmospheric Sciences)
Gingras, Murray (Earth and Atmospheric Sciences)
Keddie, Andrew (Biological Sciences)
Department
Department of Earth and Atmospheric Sciences
Specialization

Date accepted
2015-03-16T14:18:46Z
Graduation date
2015-06
Degree
Doctor of Philosophy
Degree level
Doctoral
Abstract
The carbonate succession on Grand Cayman and Cayman Brac, located close to each other in the Caribbean Sea, includes the Bluff Group that is formed of the unconformity-bounded Brac Formation (early Oligocene), Cayman Formation (middle Miocene), and Pedro Castle Formation (early Pliocene), which is overlain by the Ironshore Formation (Pleistocene). The erosional unconformities that now separate these formations developed during the sea-level lowstands. The karst relief of at least 62 m on the upper surface of the Cayman Formation on Grand Cayman provides the minimum estimate for the Messinian drop of sea level in Caribbean. The rugged interior landscape and peripheral rims on this surface reflect the interplay between the rate of runoff and rainfall. Compared to Grand Cayman, the upper surface of the Cayman Formation on the uplifted central core of Cayman Brac is tilted with up to 120 m of the Cayman Formation lost to erosion, more pronounced peripheral rims, and lower karst relief. Nevertheless, exposures of this formation on the two islands are characterized by phytokarst, sinkholes, photolineaments, and solution-widened joints. Such comparisons indicate that uplift played an important role in the development of this erosional unconformity. Sinkholes developed in the Cayman Formation on Grand Cayman and Cayman Brac are open, filled with water, or filled with lithified deposits that include rootcrete, and breccias that are formed of dolostone, white limestone and black limestone lithoclasts that are held in white (oncoids or skeletal), yellow, and orange limestone matrices. The rare earth elements (REE) and isotopes of these sinkhole-filling deposits are different from those derived from the bedrock carbonates. Interpretation of these data indicates that the (1) rootcrete, oncoids, and the red and orange limestones are terrestrial in origin, whereas the other sinkhole-filling deposits are of marine origin, (2) red and orange limestones probably formed under more arid condition than the other sinkhole-filling deposits, (3) formation of the black limestone lithoclasts, oncoids, and rootcrete was probably related to biogenic factors, and (4) REE can be used to determine provenance. The sinkhole-filling deposits offer a record of the processes that took place while the erosional unconformities were developing.
Language
English
DOI
doi:10.7939/R3N58CV08
Rights
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication

File Details

Date Uploaded
Date Modified
2015-06-15T07:08:14.559+00:00
Audit Status
Audits have not yet been run on this file.
Characterization
File format: pdf (PDF/A)
Mime type: application/pdf
File size: 108164628
Last modified: 2015:10:22 04:17:53-06:00
Filename: Liang_Ting_201503_PhD.pdf
Original checksum: 66a59091ba90aef17f4967d632494675
Activity of users you follow
User Activity Date