Department
Geosciences and Geological and Petroleum Engineering
Major
Geology
Research Advisor
Hogan, John P.
Advisor's Department
Geosciences and Geological and Petroleum Engineering
Funding Source
UMR Opportunities for Undergraduate Research Experiences (OURE) Program
Abstract
A stalactite collected from a concrete structure near Gweru Zimbabwe, South Africa was investigated to better understand growth mechanisms for stalactites. The sample is composed of relatively concentric rings, alternating between light brown and dark brown in color. These differences have been attributed to reflect growth during the "wet" and "dry" seasons in Gweru. The petrographic microscope was used to characterize the nature of the rings and to count the rings in an attempt to determine the stalactite's age. Physical characteristics of individual layers, such as crystal form, indicate these layers preserve a more complex growth history than simply recording seasonal changes. It is suggested that each ring is related to separate significant rainfall events during the wet season with no deposition during the dry season. Stalactite rings thus provide a good record of past rainfall activity and will require other methods to establish the calendar age of rings.
Biography
Leah Bahr is a senior undergraduate student at the University of Missouri-Rolla, majoring in Geology.
Research Category
Natural Sciences
Presentation Type
Poster Presentation
Document Type
Poster
Location
Havener Center, Carver-Turner Room
Presentation Date
11 April 2007, 1:00 pm - 3:00 pm
Model for Stalactite Growth
Havener Center, Carver-Turner Room
A stalactite collected from a concrete structure near Gweru Zimbabwe, South Africa was investigated to better understand growth mechanisms for stalactites. The sample is composed of relatively concentric rings, alternating between light brown and dark brown in color. These differences have been attributed to reflect growth during the "wet" and "dry" seasons in Gweru. The petrographic microscope was used to characterize the nature of the rings and to count the rings in an attempt to determine the stalactite's age. Physical characteristics of individual layers, such as crystal form, indicate these layers preserve a more complex growth history than simply recording seasonal changes. It is suggested that each ring is related to separate significant rainfall events during the wet season with no deposition during the dry season. Stalactite rings thus provide a good record of past rainfall activity and will require other methods to establish the calendar age of rings.
