Thesis (Ph.D.)--Tennessee Technological University, 2007. / Bibliography: leaves 206-211.

Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaves 112-114). Also available via the Internet.

The greater part of land in the area south of Pretoria is underlain by dolomite from the Chuniespoort Group of the Transvaal Supergroup. In South Africa dolomite rock has a notorious reputation for the formation of sinkholes and subsidences. Thousands of people reside and work in the Centurion area, where numerous sinkholes have occurred causing damage and in some instances loss of property. Centurion has rapidly densified over the last 40 years. This study deals with the hazard of sinkhole formation in the Centurion CBD and surrounding area as well as comparing the Method of Scenario of Supposition by Buttrick and van Schalkwyk (1995) based on an ‘abused’ land use situation to this ‘managed’ area in Centurion. Various classification systems have been proposed since the 1970’s in an attempt to evaluate the stability of sites on dolomite in South Africa and a summary of each are provided in the dissertation. The classification system that is currently used in South Africa is the method proposed by Buttrick (1992) which is known as the Method of Scenario Supposition. A total of 119 sinkholes have been recorded in the Centurion CBD area since the early 1970’s. Three lives havebeen lost as a result of a sinkhole in the area and a total of seven houses or units had to be demolished. Draft guidelines for allocation of each hazard class has been developed, which is referred to as the proposed ‘Modified Method of Scenario Supposition’. This is mainly based on the dolomite bedrock depth and the mobilization potential of the overlying horizons. Eight Inherent Hazard Classes are present which classify an area into having a low, medium or high hazard of sinkhole formation. After each borehole was assigned its specific inherent hazard class, the information was recorded in ESRI ArcGIS® software. The Spatial Analyst® extension of ArcMap® was used to create a map showing the areas of low, medium and high hazard of sinkhole formation. The map generally indicates a medium to high susceptibility to sinkhole formation in the Centurion CBD area with pockets of low hazard areas. This hazard map was then used to make recommendations for each of the eight Inherent Hazard Classes on suitable development types as per the draft SANS 1936-1:2012 guidelines. Various methods are used to calculate the hazard of sinkhole formation using data such as the historicaloccurrence of sinkholes, geological information and the hazard map. These results are used to compare this ‘managed land’ to the ‘abused land’ scenario used by Buttrick and van Schalkwyk (1995). Overall, the hazard for sinkhole formation in the Centurion CBD area does not correlate well with the method proposed by Buttrick and van Schalkwyk (1995). According to the anticipated number of events by Buttrick and van Schalkwyk far more sinkholes should have occurred in the high hazard areas. In contrast, the most sinkholes in the Centurion CBD area occurred in the areas classified as having a medium hazard for sinkhole formation. / Dissertation (MSc)--University of Pretoria, 2013. / Geology / unrestricted

Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1916. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed April 1, 2009) Includes bibliographical references (p. 20).

Thesis (Ph.D.)--Kent State University, 2010. / Title from PDF t.p. (viewed Apr. 28, 2010). Advisor: Mandy Munro-Stasiuk. Keywords: Remote Sensing. Includes bibliographical references (p. 264-275).

Karst related sinkholes and subsidence‟s occur on areas underlain by Chuniespoort Group dolomite bedrock in the Gauteng Province. Dolomite land occurs across several South African provinces; however sinkhole and subsidence formation in Gauteng is more well-known than in of the other provinces. Thousands of sinkhole and subsidence events have occurred in the past 60 years. In the past, data on sinkhole and subsidence occurrence has been amassed separately by various consultants, companies and state authorities. There is currently no legal requirement for sinkhole and subsidence events to be reported to a central authority, yet this data is crucial for future assessment of sinkhole hazards and decision making. This study focuses on the dolomitic land areas within four Gauteng municipalities, vulnerable to karst related sinkhole and subsidence formation. Historical as well as current information regarding the sinkhole record for Gauteng was compiled from various sources to develop as comprehensive an inventory of the study area as possible. The importance of sinkhole inventories are reviewed as well as the expediency and efficiency of Geographic Information Systems in data capturing and viewing. Data originates from numerous sources and compiling a comprehensive database presented many challenges, most importantly the large percentage of missing data that could not be retrieved and that the format and quality varies. Only karst related sinkhole, subsidences and crack events prior to 31 December 2011 were considered in this study. The data compiled is only an estimation of the number of events that has occurred in Gauteng. Once all the available sinkhole and subsidence data was collected and compiled, it was organized into multiwave frequency tables and various aspects were analyzed. The data collected, although limited in some cases, is used in statistical analysis to investigate the relationship between the formation of sinkholes and subsidences and underlying geology, size distributions, frequency of events and external influences. Results indicate that to date just over 3000 events (sinkholes, subsidences and ground cracks) are recorded within the study areas, and:  Sinkholes and subsidences are still regularly occurring in areas underlain by dolomite in Gauteng, however based on available data, events in the West Rand and Tshwane appear to show decreasing trend over the last decade.  More events occur in high rainfall months or years (due to increased ingress water entering the ground profile).  The most dominant type of event recorded is sinkholes.  Overall the largest percentage of events has occurred on the chert-rich Monte Christo Formation and Eccles Formation.  Triggering mechanisms were considered for the different areas: on the West Rand most occurrences before 1984 were due to dewatering while after 1984, most are attributed to ingress. The largest percentage of events on the West Rand has occurred in the Oberholzer Groundwater Compartment. In Tshwane almost all occurrences can be attributed to ingress, while in Ekurhuleni, just under a quarter of events were identified as due to dewatering.  When considering sinkhole and subsidence size and depth distributions; the largest percentage of sinkholes in the West Rand (>60%) are large to very large (i.e. from greater than 5m to greater than 15m diameter), the largest percentage of sinkholes in Tshwane (>60%) are medium to large (i.e. from greater than 2m to less than or equal to 15m diameter) and the largest percentage of events in Ekurhuleni (>70%) are small to medium (i.e. less than or equal to 5m diameter).  When considering size distribution on the different formations, it was not possible to determine if certain sizes were more prevalent for specific formations. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Geology / unrestricted

The primary reason for making the research study on "Sinkholes in Florida and Their Effect on Man's Environment", is an interest in learning more about this somewhat unique phenomenon and how it is likely to affect man in the future, particularly here in Central Florida. This is significant at this time in view of the large number of existing sinkholes, the frequency of occurrence, the projected population and economic growth, and the possible impact this growth may have on future sinkhole occurrences. The research concentrated on possible causes, effects, frequencies, locations and mean of predicting future sinkhole development. There is a large amount of published material on possible causes, including general agreement on some fundamental aspects. There is controversy however, among qualified experts on some of the finer pints. The research revealed a small amount of data on effects and very little organized activity to collect and evaluate data on all known sinkholes as to location, frequency of occurrence, conditions found at the site, and known geological data pertaining to the area. Descriptive data on conditions is expected to include diameter, depth, size of the opening in the limestone and, if possible, characteristics of the cavern, including whether or not limestone debris was found. Several studies on possible means of predicting potential sinkhole activity were found.

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The goal of this research project is to identify the efficacy of the ground penetrating radar (GPR) technique in locating underground coal mine related subsidence features at Malakoff and Bastrop, Texas. The work at Malakoff has been done in collaboration with the Railroad Commission of Texas (RRC). RRC has been carrying out reclamation of abandoned underground coal mines at Malakoff since the early 1990’s. The history of the specific mining operations (at Malakoff and Bastrop) that took place in the early 1900’s has been difficult to ascertain; therefore, the use of a geophysical techniques like ground penetrating radar to identify hidden voids and potential subsidence features is vital for future reclamation process. Some of the underground mine workings at the field site have collapsed over time affecting the topography by creating sinkholes. GPR data, employing 25 MHz, 50 MHz and 100 MHz frequency antennae, have been collected in common offset patterns and azimuthal pattern. GPR data indicate the mine tunnels possibly connecting existing sinkholes by radargram hyperbolae that correspond with mine openings observed visually or during reclamation. This study also denotes the importance of understanding the variable physical properties of the stratigraphy, which could lead to false alarms by misinterpretation of the radar signals. Natural and man-made above-ground structures cause obstructions in data collection, and hence an optimal design is required for each survey. RRC successfully ground-truthed the data during its reclamation process. In turn, the acquired geophysical data helped to guide the reclamation. At Bastrop, GPR data along with historical documentation led to the conclusion that coal mining did exist in this region but is not a major concern to the immediate stability and safety of the field site. It can be concluded from both the studies that the GPR technique identifies anomalous shafts/tunnels possibly connecting potential failure.