Theses and Dissertations
Issuing Body
Mississippi State University
Advisor
Mylroie, John E.
Committee Member
Schmitz, Darrel W.
Committee Member
Cooke, William H.
Date of Degree
5-7-2005
Document Type
Graduate Thesis - Open Access
Major
Geosciences
Degree Name
Master of Science
College
College of Arts and Sciences
Department
Department of Geosciences
Abstract
Rota Island, the southernmost island in the Commonwealth of the Northern Mariana Islands in the western Pacific, has the types of caves previously documented on the other limestone mantled islands in the Mariana Arc that have been investigated for caves: Aguijan, Guam, Tinian and Saipan. Caves developed at the edge of the fresh-water lens by zones of enhanced carbonate dissolution produced by fresh-water/salt-water mixing are most common. Among these mixing zone caves, flank margin caves dominate. Flank margin caves were found singly and in extensive horizons representing significant sea-level still stands. However, another type of mixing zone cave was found on Rota in numbers not documented on neighboring islands. Mixing zone fracture caves, apparently formed as zones of enhanced dissolution, produced fresh-water discharging from the lens along fractures, migrated vertically as sea-level changed. Some mixing zone fracture caves on Rota are developed in clusters from two to four caves. The mixing zone caves of Rota reflect the interaction of eogenetic limestone, glacioeustasy, local tectonics and enhanced carbonate dissolution via mixing of disparate waters. The development of mixing zone caves on Rota is in agreement with the Carbonate Island Karst Model (CIKM). Rota has a few caves developed along the contact between limestone and the insoluble volcanic rock that makes up the core of the island. The most important of these is Water Cave, a large spring that is the source for most of the municipal water on Rota. Rota also two extensive zones of vertical fissures developed along bedrock fractures; Fissure City and As Mundo Fissure Zone. In addition, Rota has one cave apparently developed along a fault; Gagani Cave. Some of the caves documented on Rota are difficult to classify and warrant further investigation.
URI
https://hdl.handle.net/11668/20519
Recommended Citation
Keel, Thomas M., "The Caves and Karst of Rota Island, Commonwealth of the Northern Mariana Islands" (2005). Theses and Dissertations. 4281.
https://scholarsjunction.msstate.edu/td/4281
Comments
limestone||eogenetic||flank margin||CIKM||Commonwealth of the Northern Mariana Islands||Rota||cave||karst||Carbonate Island Karst Model