Castleguard Cave Research Articles

The origin of sulphates in Castleguard Cave, Columbia Icefields, Canada

δ 34S-values of sulphate minerals from Castleguard Cave and the bedrock that encloses the cave suggest that the oxidation of pyrite is a possible source for the majority of gypsum seen in the cave. One gypsum sample provides an exception suggesting that anhydrite may also be a source in some cases. The provenance of a sample of mirabilite is harder to determine since its composition may have been affected by bacterial activity as suggested by δ 34S- and δ 180-values of the sulphate ion. Mechanisms of sulphate precipitation in the cave were examined with reference to δ 180- and δD-values of the sulphate mineral crystallization waters and the cave water. Gypsum appears to have been precipitated at an earlier stage partly by evaporation and partly by expulsion of CO 2 from sulphate-bearing solutions. In contrast, mirabilite may have formed in a highly evaporative environment such as is encountered presently. Valley deepening has breached the cave in post-Wisconsin times allowing air to move through it; subsequent evaporation may have led to the formation of mirabilite.

Glacier hydrology and the potential for subglacial karstification

Contemporary models of subglacial hydrology identify two quasi-independent hydrologic systems at the bed of temperate alpine glaciers: a dendritic, low pressure conduit network and a more extensive, high pressure regelation film. Observations in Castleguard Cave beneath the Columbia Icefield suggest that this distinction continues into the groundwater system; the conduit waters draining through erosional shafts, and the film waters percolating through a network of fine cracks and fissures, depositing calcite when encountering the cave atmosphere. The depleted aggressiveness of glacial meltwater limits its potential for karst development, even if comparatively large discharges are involved. However, conduit waters arc capable of developing short lengths of cave passage during a glacial epoch. Such passages can develop as cross-links to pre-existing karst, and may appear anomalous in the post-glacial landscape. The hydrochemical nature of the regelation film is unknown, although some erosional evolution is probably occurring along the flow route. The regelation-percolation flow system may be important in the initiation of karst flow routes, although the nature of the regelation film prevents further development, and subsequent evolution must involve conduit waters. Subglacial karst is most likely to develop in elevated areas, beneath comparatively thin ice, around the firn line, rather than beneath valley glaciers or high under the upper accumulation zone. Karst may cause relatively low ice velocities and decrease glacial erosion rates.

Climate and Natural Radon Levels in Castleguard Cave, Columbia Icefields, Alberta, Canada

Castleguard Cave has a climate dominated by chimney-effect winds, due to temperature differences between interior and exterior air. A theory is developed relating the magnitude of winds to these di...

The Physiography and Speleogenesis of Castleguard Cave, Columbia Icefields, Alberta, Canada

Castleguard Cave is developed in massive limestones of the upper Cathedral Formation (Middle Cambrian), overlain by shaly or dolomitic carbonates that function today as a leaky caprock. The cave co...

Climate and Natural Radon Levels in Castleguard Cave, Columbia Icefields, Alberta, Canada

Climate and Natural Radon Levels in Castleguard Cave, Columbia Icefields, Alberta, Canada

The Physiography of the Castleguard Karst and Columbia Icefields Area, Alberta, Canada

The Columbia Icefields are highland ice caps developed upon benchlands of massive platform carbonates in the Main Ranges, Rocky Mountains. Ice is discharged via major valley glaciers, including South Glacier, Castleguard Valley. The karst is developed along the southeast edge of the central icefield, extends beneath it, and drains to springs in Castleguard Valley. Altitudinal range of the karst is 1600 to 2600 m a.s.l. Mean annual temperature is estimated to range from 0 to -7?C over this range. Treeline is at ca. 2100 m. All cirques and valleys were occupied by ice during the late Wisconsinan Glaciation. Modern glaciers are ca. 100 to 300 m in thickness and are receding from well-marked Neoglacial moraines. Periglacial features are prominent on high carbonate surfaces that escaped Neoglacial cover. The principal surface karst features are (1) subglacial precipitates found on newly exposed Neoglacial surfaces; (2) varieties of sinkholes seen on all exposed carbonates above 2000 m; (3) families of springs, most below 2000 m. Castleguard Cave is a major relict system. The first interpretations of the karst, using simple morphological evidences alone, supposed that the Cave was drained by glacial entrenchment during the Wisconsinan Glaciation. Two modern groundwater caves developed beneath it.

The Mineralogy of Castleguard Cave, Columbia Icefields, Alberta, Canada

A mineralogical survey at Castleguard Cave has revealed complex suites of carbonate and sulfate minerals, plus seasonal and permanent ice. Carbonate minerals observed (and number of occurrences in 55 samples) are as follows: calcite (43), huntite (15), hydromagnesite (6), aragonite (4), monohydrocalcite (1). Sulfate minerals observed (number of occurrences in 10 samples) are: gypsum (9), thenardite/mirabilite (2), epsomite (1). Ancient massive dripstone and flowstone deposits consist only of calcite. Smaller dripstones, chalky coatings on dripstone, thin flowstone crusts, erratics, and pasty wall deposits (moonmilk) were commonly combinations of calcite plus huntite. Aragonite occurs mainly as crystalline wall concretions associated with deposits and as small anthodites. Hydromagnesite and monohydrocalcite are only found as dry, crusty, moonmilk wall deposits. Distribution of carbonate and sulfate minerals is related to the thermal regime and presence of discrete seepage inputs. Small calcite speleothems occur to some extent throughout the cave. Massive dripstones and abundant decoration are restricted to sites of present or past seepage concentration. Sulfate mineralization and basic and hydrated carbonates are confined to warm, drier portions of the central cave. Chemical and stable isotope data indicate that calcite is precipitated at constant CO2 partial pressure. Evaporation is the primary process responsible for the presence of the diverse sulfate and exotic carbonate minerals in the cave.

Growth Mechanisms of Recent Speleothems from Castleguard Cave, Columbia Icefields, Alberta, Canada, Inferred from a Comparison of Uranium-Series and Carbon-14 Age Data

Growth Mechanisms of Recent Speleothems from Castleguard Cave, Columbia Icefields, Alberta, Canada, Inferred from a Comparison of Uranium-Series and Carbon-14 Age Data

Growth Mechanisms of Speleothems in Castleguard Cave, Columbia Icefields, Alberta, Canada

In spite of its location beneath high alpine terrain and active glaciers, Castleguard Cave contains many actively growing calcite speleothems. Four hypotheses as to their growth mechanism were test...

The Physiography and Speleogenesis of Castleguard Cave, Columbia Icefields, Alberta, Canada

Castleguard Cave is developed in massive limestones of the upper Cathedral Formation (Middle Cambrian), overlain by shaly or dolomitic carbonates that function today as a leaky caprock. The cave co...

Clastic Sediments in Castleguard Cave, Columbia Icefields, Alberta, Canada

Castleguard Cave contains a variety of clastic sediments of both allochthonous and autochthonous origin. The head of the cave, lying beneath the Columbia Icefield, displays breakdown and glaciofluvial injecta that are ancient. Principal deposits in the central cave are the eroded remains of at least three phases of silt filling. These are interpreted as varved sequences deposited under full glacial conditions. They are older than 140,000 BP. A channel abandonment facies occupies the inner part of the downstream entrance complex. The outer part is prone to flooding today and contains a remarkable shingle beach formed in situ where floodwaters must rise vertically.

Growth Mechanisms of Recent Speleothems from Castleguard Cave, Columbia Icefields, Alberta, Canada, Inferred from A Comparison of Uranium-Series and Carbon-14 Age Data

Growth Mechanisms of Recent Speleothems from Castleguard Cave, Columbia Icefields, Alberta, Canada, Inferred from A Comparison of Uranium-Series and Carbon-14 Age Data

Holes-in-the-F1oor passage, Castleguard Cave, Banff National Park, Alberta. (Photo by D. C. Ford.)

Holes-in-the-F1oor passage, Castleguard Cave, Banff National Park, Alberta. (Photo by D. C. Ford.)

The Subterranean Crustacean Fauna of Castleguard Cave, Columbia Icefields, Alberta, Canada, and Its Zoogeographic Significance

A biological survey of Castleguard Cave has shown that the inner cave is inhabited by two species of aquatic crustaceans, the asellid isopod Salmasellus steganothrix and the crangonyctid amphipod Stygobromus canadensis, both of which are blind and unpigmented. The isopod is abundant throughout the portions of the system containing sediment-rich pools and was found in areas of the cave which lie beneath the Columbia Icefields. The amphipod, which is unique to Castleguard Cave, was found only in one series of pools about 2 km from the entrance. The occurrence of these aquatic species so far inside an area fully glacierized during the Wisconsinan and even at present partially under a permanent icefield suggests that they may be remnants of very old preglacial distributions. Since it is known that the cave has remained intact and internally ice free for more than 720,000 yr, it is hypothesized that it has served as a subglacial refugium for these organisms.

The Occurrence of an Unusual Type of Pisolite: The Cubic Cave Pearls of Castleguard Cave, Columbia Icefields, Alberta, Canada

The Occurrence of an Unusual Type of Pisolite: The Cubic Cave Pearls of Castleguard Cave, Columbia Icefields, Alberta, Canada

The Occurrence of an Unusual Type of Pisolite: The Cubic Cave Pearls of Castleguard Cave, Columbia Icefields, Alberta, Canada

Nests of calcite pisolites (“cave pearls”) of approximately spherical form are common features in caves. They grow by accretion of calcium carbonate around rolling nucleii. Nests of cubic pearls ar...

The Subterranean Crustacean Fauna of Castleguard Cave, Columbia Icefields, Alberta, Canada, and its Zoogeographic Significance

The Subterranean Crustacean Fauna of Castleguard Cave, Columbia Icefields, Alberta, Canada, and its Zoogeographic Significance

The Antiquity of Castleguard Cave, Columbia Icefields, Alberta, Canada

Several sections of Castleguard Cave contain abundant, massive fossil speleothem deposits. Twenty-one samples have been dated by the 230Th/234U method. Ten of them are older than 350 ka (1 ka = 100...

Stygobromus canadensis, a new subterranean amphipod crustacean (Crangonyctidae) from Canada, with remarks on Wisconsin refugia

Stygobromus canadensis, new species, is described from Castleguard Cave, a large alpine cave located in the Canadian Rockies of Alberta. This is the first subterranean amphipod crustacean reported from Canada and the ninth member of the genus found north of the southern limits of Pleistocene glaciation. Considering the evidence against postglacial dispersal (e.g., endemicity and lack of close affinity with species living farther south), and the presence of a subterranean isopod in the same cave, it is hypothesized that these small aquatic crustaceans survived the Wisconsin glaciers in deep, groundwater refugia under the ice. There is some evidence to suggest that Castleguard Cave, itself, could have served as such a refugium.