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This is the first detailed examination of the karst geomorphology of the Bruce Peninsula. It attempts to review all aspects including pavement phenomena and formation (microkarst features), surface and subsurface karst hydrology (meso to macro scale) and water chemistry. The latter is based on over 250 samples collected in 1973 and 1974.
The dolomite pavement is the best example of its kind that has been described in the literature. It covers much of the northern and eastern parts of the peninsula and can be differentiated into three types based on karren assemblages. Two of these are a product of lithology and the third reflects local environmental controls. The Amabel Formation produces characteristic karren such as rundkarren, hohlkarren, meanderkarren, clint and grike, kamentizas and rillenkarren on glacially abraded biohermal structures. The Guelph Formation develops into a very irregular, often cavernous surface with clint and grike and pitkarren as the only common recognizable karren. The third assemblage is characterized by pitkarren and is found only in the Lake Huron littoral zone. Biological factors are believed to have played a major role in the formation of the pavement. Vegetation supplies humic acids which help boost the solution process and helps to maintain a wet surface. This tends to prolong solution and permit the development of karren with rounded lips and bottoms.
Three types of drainage other than normal surface runoff are found on the Bruce. These are partial underground capture of surface streams, complete underground capture (fluvio-karst), and wholly vertical drainage without stream action (holokarst). Holokarst covers most of the northern and eastern edge of the peninsula along the top of the escarpment. Inland it is replaced by fluvial drainage, some of which has been, or is in the process of being captured. Four perennial streams and one lake disappear into sinkholes. These range from very simple channel capture and resurgence, as shown by a creek east of Wiarton, to more mature and complex cave development of the St. Edmunds cave near Tobermory. Partial underground capture represents the first stage of karst drainage. This was found to occur in one major river well inland of the fluvio-karst and probably occurs in other streams as well. This chapter also examines the possible future karst development of the Bruce and other karst feature such as isolated sinks and sea caves.
The water chemistry presented in Chapter 5 represents the most complete data set from southern Ontario. It is examined on a seasonal basis as well as grouped into classes representing water types (streams, Lake Huron and Georgian Bay, inland lakes, swamps, diffuse springs and conduit springs). The spring analyses are also fitted into climatic models of limestone solution based on data from other regions of North America. It was found that solution rates in southern Ontario are very substantial. Total hardness ranges from 150 to 250 ppm (expressed as CaCO3) in most lakes and streams and up to 326 ppm in springs. These rates compare with more southerly latitudes. The theoretical equilibrium partial pressure of CO2 was found to be the most significant chemical variable for comparing solution on different kinds of carbonates and between glaciated and non-glaciated regions. Expect for diffuse flow springs and Lake Huron, the Bruce data do not separate easily into water types using either graphical or statistical (i.e. Linear Discriminant Analysis) analyses. This is partly because of the seasonality of the data and because of the intimate contact all waters have with bedrock.
The intensively glaciated mountains of the Picton Range - Mt. Bobs area in southwestern Tasmania contain prominent karst features that have been developed in carbonate formations of Devonian, Ordovician and possibly Precambrian age. This paper reviews the extent of the karst and glacial features and records the tracing of the underground drainage from the alpine Lake Sydney. Glacial erosion has exposed areas of limestone to karstification and glacial diversion of drainage has played a critical role in the evolution of the present underground drainage patterns. Prior to the late Last Glacial Stage the deflection of marginal meltwaters from the former Farmhouse Creek Glacier against the Burgess - Bobs Saddle led to the development of an underground breach of a major surface drainage divide. Subglacial or submarginal meltwaters associated with a much smaller glacier that developed in the same valley during the late Last Glacial Stage probably played a significant role in the breaching of a minor divide within the Farmhouse Creek catchment. This led to the development of an underground anabranch of Farmhouse Creek that by-passes the glacial Pine Lake. However, it is possible that the latter diversion is entirely Holocene in age and is related to postglacial dilation of the limestone rather than meltwater flows.
A speleological expedition to Vanishing Falls explored a 2.3km long cave associated with the underground course of the Salisbury River, and provided the first systematic documentation of karst features and cave ecology in this remote area. The caves host a fauna comprising at least 30 taxa, of which probably more than 14 are troglobitic or stygobiontic. This fauna exhibits a high degree of troglomorphy, with some species likely to be endemic to the Vanishing Falls karst.
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