A Geomorphological Assessment of the Chillagoe Karst Belt, Queensland, 1976, Marker, Margaret E.

The geomorphological characteristics of the Chillagoe karst belt are analysed in terms of an evolution controlled by seasonally arid climatic conditions and lithological variation in the metamorphosed host rock.

Variation among populations of the troglobitic Amphipod Crustacean Crangonyx antennatus Packard living in different habitats. I. Morphology., 1977, Dickson Gary W.

Populations of the troglobitic (i.e., obligatory cavernicole) amphipod Crangonyx antennatus living in two distinct aquatic habitats were examined for possible morphological variation. Collections were made seasonally for one year in six Lee Co., Virginia caves, three with mud-bottom pools and three with small gravel-bottom streams. Environmental parameters thought to influence population variation were recorded for each of the six caves. Body length of mature amphipods was found to be greater in the mud-bottom pool habitats, whereas stream amphipods possessed more first antennal segments per unit body length. Variation was also observed in integument coloration; stream amphipods were characterized by a brownish integument and pool amphipods a whitish integument. Differences in the type and amount of available food in the two habitats is considered the most important environmental parameter affecting morphological variation. The population variation noted between habitats is believed indicative of the adaptive flexibility of this vagile troglobitic species.

Identification of the origin of oreforming solutions by the use of stable isotopes, 1977, Sheppard S. M. F. ,

SynopsisThe four major different types of water -- magmatic, metamorphic, sea water and/or connate, and meteoric water -- have characteristic hydrogen (D/H) and oxygen (18O/16O) isotope ratios. Applied to the analysis of isotopic data on hydrothermal minerals, fluid inclusions and waters from active geothermal systems, these ratios indicate that waters of several origins are involved with ore deposition in the volcanic and epizonal intrusive environment. Water of a single origin dominates main-stage mineralization in some deposits: magmatic -- Casapalca, Peru (Ag-Pb-Zn-Cu); meteoric -- Butte, Montana (Cu-Zn-Mn), epithermal deposits, e.g. Goldfield, Tonopah, Nevada (Ag-Au), Pachuca, Mexico (Ag-Au), San Juan Mountains District, Colorado (Ag-Au-Pb-Zn); sea water -- Troodos, Cyprus (Fe-Cu), Kuroko, Japan (Fe-Cu-Pb-Zn). Solutions of more than one origin are important in certain deposits (magmatic and meteoric -- porphyry copper and molybdenum deposits) and are present in many. In the porphyry Cu-Mo deposits the initial major ore transportation and alteration processes (K-feldspar-biotite alteration) are magmatic-hydrothermal events that occur at 750-500{degrees}C. These fluids are typically highly saline Na-K-Ca-Cl-rich brines (more than 15 wt % equivalent NaCl). The convecting meteoric-hydrothermal system that develops in the surrounding country rocks with relatively low integrated water/rock ratios (less than 0.5 atom % oxygen) subsequently collapses in on a waning magmatic-hydrothermal system at about 350-200{degrees}C. These fluids generally have moderate to low salinities (less than 15 wt % equivalent NaCl). Differences among these deposits are probably in part related to variations in the relative importance of the meteoric-hydrothermal versus the magmatic-hydrothermal events. The sulphur comes from the intrusion and possibly also from the country rocks. Deposits in which meteoric or sea water is the dominant constituent of the hydrothermal fluids come from epizonal intrusive and sub-oceanic environments where the volcanic country rocks are fractured or well jointed and highly permeable. Integrated water/rock ratios are typically high, with minimum values of 0.5 or higher (atom % oxygen) -- the magmatic water contribution is often drowned out'. Salinities are low to very low (less than 10 wt % equivalent NaCl), and temperatures are usually in the range 350-150{degrees}C. The intrusion supplies the energy to drive the large-scale convective circulation system. The sulphur comes from the intrusion, the country rocks and/or the sea water. Argillic alteration, which occurs to depths of several hundred metres, generated during supergene weathering in many of these deposits is isotopically distinguishable from hydrothermal clays

Karst Hydrogeology and Geomorphology of the Sierra de El Abra and the Valles-San Luis Potosí Region, México, PhD Thesis, 1977, Fish, Johnnie Edward

The general objective of this work was to develop a basic understanding of the karst hydrology, the nature and origin of the caves, the water chemistry, the surface geomorphology, and relationships among these aspects for a high relief tropical karst region having a thick section of limestone. The Valles-San Luis Potosí region of northeastern México, and in particular, the Sierra de El Abra, was selected for the study. A Cretaceous Platform approximately 200 km wide and 300 km long (N-S) delimits the region of interest. A thick Lower Cretaceous deposit of gypsum and anydrite, and probably surrounded by Lower Cretaceous limestone facies, is overlain by more than 1000 m of the thick-bedded middle Cretaceous El Abra limestone, which has a thick platform-margin reef. The Sierra de El Abra is a greatly elongated range along the eastern margin of the Platform. During the late Cretaceous, the region was covered by thick deposits of impermeable rocks. During the early Tertiary, the area was folded, uplifted, and subjected to erosion. A high relief karst having a wide variety of geomorphic forms controlled by climate and structure has developed. Rainfall in the region varies from 250-2500 mm and is strongly concentrated in the months June-October, when very large rainfalls often occur.
A number of specific investigations were made to meet the general objective given above, with special emphasis on those that provide information concerning the nature of ground-water flow systems in the region. Most of the runoff from the region passes through the karstic subsurface. Large portions of the region have no surface runoff whatsoever. The El Abra Formation is continuous over nearly the whole Platform, and it defines a region of very active ground-water circulation. Discharge from the aquifer occurs at a number of large and many small springs. Two of them, the Coy and the Frío springs group, are among the largest springs in the world with average discharges of approximately 24 m³/sec and 28 m³/sec respectively. Most of the dry season regional discharge is from a few large springs at low elevations along the eastern margin of the Platform. The flow systems give extremely dynamic responses to large precipitation events; floods at springs usually crest roughly one day after the causal rainfall and most springs have discharge variations (0max/0min) of 25-100 times. These facts indicate well-developed conduit flow systems.
The hydrochemical and hydrologic evidence in combination with the hydrogeologic setting demonstrate the existence of regional ground-water flow to several of the large eastern springs. Hydrochemical mixing-model calculations show that the amount of regional flow is at least 12 m³/sec, that it has an approximately constant flux, and that the local flow systems provide the extremely variable component of spring discharge. The chemical and physical properties of the springs are explained in terms of local and regional flow systems.
Local studies carried out in the Sierra de El Abra show that large conduits have developed, and that large fluctuations of the water table occur. The large fossil caves in the range were part of great deep phreatic flow systems which circulated at least 300 m below ancient water tables and which discharged onto ancient coastal plains much higher than the present one. The western margin swallet caves are of the floodwater type. The cave are structurally controlled.
Knowledge gained in this study should provide a basis for planning future research, and in particular for water resource development. The aquifer has great potential for water supply, but little of that potential is presently used.

Microflora and activity of functional groups in the sediments of three caves of Central Italy., 1978, Fumanti B. , Pasqualini A. , Visonà L.

A comparative study is presented of the microflora of sediments in three caves with different trophic characteristics. Quantitative and qualitative variations of microflora were investigated for one year by studying the total microflora and the activity of the nitrogen cycle functional groups. Data were compared with those of other works of previous authors. Results show that the quantity and kind of organic matter of sediment are most important factors regulating the abundance and activity of cavernicolous microflora. The experimental part of this paper is prefaced by a digest of investigations previously carried out on cavernicolous microflora and by a report of topographic, geomorphologic, hydrologic and trophic characteristics of the caves examined.

Karst development in Ordovician carbonates: Western Platform of Newfoundland, Master of Science (MS) Thesis, 1978, Karolyi, Marika Sarolta

The Appalachian fold belt system in Newfoundland is divided into three tectonic divisions: Western Platform; Central Mobile Belt; Avalon Platform Rocks of the Western Platform range in age from Precambrian to Carboniferous. Major karst areas are found there is Ordovician and Carboniferous rocks. Karst features of the study area (Goose Arm to Bonne Bay Big Pond) are in the Ordovician carbonates of the undivided St. George and Table Head Formations, covering a few hundred square kilometers. Features include karren, sinkholes, sinking streams, and karst springs, caves and other solutional and collapse features.
In the study area multiple fold and faulting episodes complicate the geology. Extensive and probably repeated glaciations have produced rugged terrane with U-shaped valleys and as much as 300m relief on the carbonates. There is variable but thick till cover. A class or classes of ice-scoured closed depressions with internal drainage are recognized. Postglacial karst forms are limited to varieties of karren (mainly littoral), small sinkholes, and cave systems that are inaccessively small in most instances. Distribution of all karst features is highly irregular.
Hydrologic patterns follow fluvial, fluviokarstic and holokarstic drainage. Large number of sinking ponds have seasonal overflow channels. The ground water drainage routes are generally short and shallow, with varied hydraulic gradients. Few instances of ground water route integration to regional springs is found.
The water chemistry of the area displays a tight normal distribution of hardness. This is attributed to the ponding effect. Seasonal trends show an overall increase in total hardness and other parameters, with some ponds showing linear increases and others cyclic variations.
Karst type and distribution is complex and irregular, but both glaciokarstic and karstiglacial development is present. The majority of karst forms point to karstiglacial development where previous karst forms have been modified by ice. Karstification is controlled by geology, rock lithology, hydraulic gradients and glacial scour and infill. Karstic processes continue to operate today, modifying the scoured basins and creating new karst forms.

Variations in Body Color and Eye Pigmentation of Asellus brevicauda Forbes (Isopoda: Asellidae) in a Southern Illinois Cave System, 1979, Lisowski, Edward A.

Relations between the location of the karst bauxites in the northern hemisphere, the global tectonics and the climatic variations during geological time, 1979, Nicolas Jean, Bildgen Pierre,

The study of the distribution of the laterites and bauxites of karst in the Northern Hemisphere shows that their location is not erratic. Most of the bauxites are ordered after their age, according to alignments indicating the existence of palaeoclimatic belts of humid intertropical type that were susceptible of having generated a laterizing pedogenesis, during geological time when these bauxites and laterites were formed. In relation to the present network of latitudes, these palaeoclimatic belts gradually took up more southerly positions, as geological time passed. A few of these formations appear, however, to be located outside the palaeclimatic belts within which they should occur. To explains this apparent anomaly, it is in consequence necessary to call into play on the one hand, the drift of the palaeoclimatic belts from the north to the south, and on the other, the mechanisms of ocean-floor spreading and of the movement of the continental plates. The results of these processes are integrated into the framework of the principles of global tectonics. They also correspond to those obtained from other disciplines, such as palaeomagnetism, palaeoclimatology, biogeography, palaeontology, etc.Extension of this study to the Southern Hemisphere can not be realized for the present, because the results of the researches relating to it in the field with which we are concerned are much too imprecise and the bibliography linked up with it too summary

Geomorphological variations of 'case hardening' in Puerto Rico., 1979, Ireland P.

Water Chemistry of the Atea Kananda and the Related Drainage Area, 1980, James, Julia M.

The Ca2+, Mg2+, alkalinity, pH and temperature have been measured in water from the Atea Kananda cave and related surface sites on the Muller Plateau (Papua New Guinea). A wide variation in the Ca2+ and Mg2+ values was found and this has been attributed to the lithology and nature (open or closed) of the water courses. From alkalinity measurements anions other than bicarbonate, probably sulphate are expected to be present in significant quantities in the cave waters. Most of the waters are aggressive. The Ca2+/Mg2+ x 10 ratio is shown to be a useful tool in predicting the origin of unknown waters in the cave. The variations of the measured and calculated parameters for groups of related surface and underground sites are presented and discussed. Tentative solution erosion rates for the Muller Plateau have been calculated and the conclusion reached that where the erosion can be placed as largely occuring on pure limestone these are high. Impure limestones and non-calcareous rocks in their catchments give anomalously low results for the main rivers. A scheme for cave development on the Muller Plateau by solution mechanisms is presented.

Small-scale spatial variations in the Chemistry of diffuse-flow seepages in Gua Anak Takun, West Malaysia, 1981, Crowther J.

Variation among Populations of the Troglobitic Amphipod Crustacean Crangonyx antennatus Packard (Crangonyctidae) Living in Different Habitats, III: Population Dynamics and Stability., 1981, Dickson Gary W. , Holsinger John R.

Populations of the troglobitic amphipod Crangonyx antennatus from caves in Lee Co., Virginia (U.S.A.) were investigated on both a short and long term basis. The dynamics of populations living in two distinct aquatic cave habitats (mud-bottom pools and gravel-bottom streams) were compared seasonably for one year. Sex ratios indicated a larger number of females in both pool and stream habitats. The majority of males in both habitats were found to be sexually mature throughout the year investigated. Seasonal fluctuations in female maturity were observed in both habitats, with larger numbers collected in June and August. In addition, a larger number of ovigerous females were observed in the spring, indicating the possibility of a circannian reproductive cycle in both pools and streams. The structure of populations from the caves studied appears to reflect a controlled recruitment of females from immature to mature stages. In order to determine the stability of population structure, collection data from a pool and a stream habitat for a l0-year period were analyzed. Population structures were found to be relatively stable over long periods in both habitats, with immature females comprising the dominant population class.

Variation of Hardness in Cave Drips at Two Tasmanian Sites, 1981, Goede, Albert

Thirteen consecutive monthly samples were collected from two drip sites at each of two Tasmanian caves: Little Trimmer at Mole Creek and Frankcombe Cave in the Florentine Valley. At one of the two drip sites in Little Trimmer a positive relationship was found between the logarithm of precipitation and the total hardness without any detectable lag effect. No such relationship was detected at the other drip site despite its close proximity. At both drip sites the hardness values fail to show a seasonal pattern and are clearly unrelated to surface temperature variations. In strong contrast both drip sites in Frankcombe Cave showed significant seasonal variation and close positive correlation with mean monthly temperature with lag times of one and two months respectively. At one of the two drip sites the influence of monthly precipitation on variations in drip hardness could also be detected. The strong temperature dependence of cave drip hardness values at these sites may well be due to soil exposure to direct insolation following recent clearfelling and burning of vegetation in the area.

Variation among populations of the yroglobitic Amphipod Crustacean Crangonyx Antennatus Packard (Crangonyctidae) living in different habitats Il. Population distribution., 1982, Dickson Gary W.

Population densities and factors affecting the distribution of the troglobitic (i.e., obligatory cavernicole) amphipod Crangonyx antennatus were examined in two distinct aquatic habitats. Observations were made seasonally for one year in six Lee Co., Virginia (U.S.A.) caves, three with mud-bottom pools and three with gravel-bottom streams. Pool habitats were found to contain greater C. antennatus densities than stream habitats, while the highest seasonal densities were recorded in August. Availability of food is considered to be the major factor allowing these increased population densities. The population distribution of C. antennatus was not found to be related to current velocity, water depth, macro-detrital food sources or isopods densities in both pool and stream habitats. The distribution of C. antennatus was observed to be related to substrate type. Substrate selection appeared to be passive in five of the amphipod populations, while in one cave, substrate selection may be influenced by competitive interactions. The fact that population distributions were not related to environmental parameters which differ markedly between habitats indicates that this troglobitic species retains ecological flexibility.

Isotopic Composition of Precipitation, Cave Drips and Actively Forming Speleothems at Three Tasmanian Cave Sites, 1982, Goede A. , Green D. C. , Harmon R. S.

Monthly samples of precipitation and cave drips were collected from three Tasmanian cave sites along a north-south transect and their 18O/16O ratios determined. At one station D/H ratios were also measured and the relationship between delta 18O and delta D values investigated. The 18O/16O and D/H ratios of monthly precipitation show marked seasonality with values correlating strongly with mean monthly temperatures. The effect of temperature on 18O/16O ratios appears to increase as one goes southwards and is at least twice as strong at Hastings (.61 deg /oo SMOW/ deg C) as it is shown at Mole Creek (.28 deg /oo SMOW/ deg C). Irregularities in the seasonal pattern of 18O/16O change are particularly pronounced at Hastings and in the Florentine Valley and can be attributed to the amount effect. For delta 18O values > -5.5 deg /oo the combined data from the three Tasmanian stations show an amount effect of .026 deg /oo SMOW/mm. Cave drips show apparently random, non-seasonal variation in the 18O / 16O isotopic compostion but the weighted mean of the 18O/16O isotope composition of precipitation provides a good approximation to their mean 18O/16O isotopic composition. In contrast to their D/H ratios for a cave drip site in Little Trimmer Cave, Mole Creek, show a distict seasonal pattern. The 18O/16O and 13C/12C ratios have been determined for a number of actively forming speleothems. With respect to 18O/16O it is found that speleothems the three sites are being deposited under conditions approaching isotopic equilibrium. The 13C/12C ratios of these speleothems are highly variable but the generally less negative values found in Frankcombe Cave (Florentine Valley) compared with the other two sites may reflect the effects of recent clearfelling in the area.