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Community news

Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That environment is all the external conditions surrounding a living thing [23].?

Checkout all 2699 terms in the KarstBase Glossary of Karst and Cave Terms


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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for clines (Keyword) returned 37 results for the whole karstbase:
Showing 1 to 15 of 37
Pseudo-karst dans les roches grso-quartzitiques de la formation Roraima (Gran Sabana, Venezuela), 1985,
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Pouyllau M. , Seurin M.
QUARTZITE PLATEAUX OF THE RORAIMA FORMATION (GRAN SABANA - VENEZUELA) - The high sandstone-quartzite plateaux of the Roraima period situated in the Gran Sabana region of south-east Venezuela have some specific macro- and micro-geomorphological characteristics. On one hand, this Precambrian sedimentary cover includes some spectacular relief consisting of high structural plateaux affected by major anticlines, synclines, and monoclines, partly dismantled by erosion. On the other hand, and on a smaller scale, pseudo-karst have developed on the surface (karren) and at depth (caves, shafts). Several hypotheses are put forward in an attempt to explain the genesis of this pseudo-karst.

Morphological clines in reduced areas. The case of Henrotius jordai (Reitter), cave-dwelling beetle from Majorca Island., 1985,
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Bells Xavier
The present paper shows a statistically significant correlation between the geographical latitude and the morphological variation of the pronotum of Henrotius jordai (Reitter) (Col. Caraboidea), cave-dwelling beetle from Majorca island, after studying the linear and curvilinear regression between these two variables. The existence of specimens situated at different heights of the regression lines leads to the conclusion that morphological variation is clinal. The phenomenon of "semi-isolation" to which the studied populations are subjected, because of their cavernicolous character, allows to explain the existence of a cline in such a restricted area as that occupied by this beetle (ca. 500 Km2). It is worth pointing out the interest in the study of these reduced clines of cavernicolous populations, because they can provide a restricted "observation field"; easier to deal with; to investigate these genetic phenomena and their evolutive implications.

Yates and other Guadalupian (Kazanian) oil fields, U. S. Permian Basin, 1990,
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Craig Dh,
More than 150 oil and gas fields in west Texas and southeast New Mexico produce from dolomites of Late Permian (Guadalupian [Kazanian]) age. A majority of these fields are situated on platforms or shelves and produce from gentle anticlines or stratigraphic traps sealed beneath a thick sequence of Late Permian evaporites. Many of the productive anticlinal structures are elongate parallel to the strike of depositional facies, are asymmetrical normal to facies strike, and have flank dips of no more than 6{degrees}. They appear to be related primarily to differential compaction over and around bars of skeletal grainstone and packstone. Where the trapping is stratigraphic, it is due to the presence of tight mudstones and wackestones and to secondary cementation by anhydrite and gypsum. The larger of the fields produce from San Andres-Grayburg shelf and shelf margin dolomites. Cumulative production from these fields amounts to more than 12 billion bbl (1.9 x 109 m3) of oil, which is approximately two-thirds of the oil produced from Palaeozoic rocks in the Permian Basin. Eighteen of the fields have produced in the range from 100 million to 1.7 billion bbl (16-271 x 106 m3). Among these large fields is Yates which, since its discovery in October 1926, has produced almost 1.2 billion bbl (192 x 106 m3) out of an estimated original oil-in-place of 4 billion bbl (638 x 106 m3). Flow potentials of 5000 to 20 000 bbl (800 to 3200 m3) per day were not unusual for early Yates wells. The exceptional storage and flow characteristics of the Yates reservoir can be explained in terms of the combined effects of several geologic factors: (1) a vast system of well interconnected pores, including a network of fractures and small caves; (2) oil storage lithologies dominated by porous and permeable bioclastic dolograinstones and dolopackstones; (3) a thick, upper seal of anhydrite and compact dolomite; (4) virtual freedom from the anhydrite cements that occlude much porosity in other fields which are stratigraphic analogues of Yates; (5) unusual structural prominence, which favourably affected diagenetic development of the reservoir and made the field a focus for large volumes of migrating primary and secondary oil; (6) early reservoir pressures considerably above the minimum required to cause wells to flow to the surface, probably related to pressures in a tributary regional aquifer

Les mouvements tectoniques rcents dans les grottes du Monte Campo dei Fiori (Lombardie, Italie), 1992,
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Bini A. , Quinif Y. , Sules O. , Uggeri A.
Recent tectonic movements have been studied in the caves of Monte Campo dei Fiori in Lombardy (Italy). These develop in limestones and dolomites ranging from the Lower Trias to the Lower Lias. In the Frassino cave, movements can be observed along the layers (shifts in galleries) as well as speleothems that have been broken and displaced. U/Th datings of speleothems indicate ages of more 350.000 years. Karstification therefore preceded neotectonic movements. On the whole, observations point out an increasing folding of the syncline of the Varese Lake, together with an uplift of the neighbouring anticlines.

HYDROGEOLOGIC CHARACTERISTICS AND DEFORESTATION OF THE STONE FOREST KARST AQUIFERS OF SOUTH CHINA, 1992,
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Huntoon P. W. ,
Stone forest aquifers comprise an important class of shallow, unconfined karstic aquifers in the south China karst belt. They occur under flat areas such as floors of karst depressions, stream valleys, and karst plains. The frameworks for the aquifers are the undissolved carbonate spires and ribs in epikarst zones developed on carbonate strata. The ground water occurs within clastic sediments which infill the dissolution voids. The aquifers are thin, generally less than 100 meters thick, and are characterized by large lateral permeabilities and small storage. The result is that the aquifers are difficult to manage because recharge during the rainy season moves rapidly out of the aquifers. Water levels fall sharply as the dry season progresses and the ground-water supply falls off accordingly. The magnitude and duration of the seasonal recharge pulse that replenishes the stone forest aquifers have been severely impacted by massive post-1958 deforestation in the south China karst region. Water that was formerly retained beyond the wet season in the forested uplands, later to be released to the stone forest aquifers under the lowland plains, now passes quickly through the system during the wet season. The loss of this seasonal upland storage has resulted in both a reduction in the volume of recharge to the lowland stone forest aquifers and a shortening of the seasonal recharge event. The result is accelerated water-level declines in the stone forest aquifers as the dry season progresses which, in turn, causes premature dewatering of wells and decreased spring discharges. This response is compounded by increased ground-water withdrawals as the people attempt to offset the declining supply. Management of the total water-supply system requires not only tinkering with the aquifer, but massive reforestation efforts to restore dry season water retention in the upland parts of the watersheds

Contribution to geomorphological and hydrogeological study of karst in Mediterranean environment: the Aït Abdi plateau (central limestone High Atlas, Maroc),PhD thesis, 1995,
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Perritaz, L.

The Ait Abdi karstic plateau is located in the heart of the calcareous High Atlas (32°N/6°W). With an area of 160 km2, it is situated between 2,200 and 3,000 meters above sea level, i.e. 800 meters above the nearest valleys and canyons. It consists of a large series of massive Bajocian limestones which form a large brachysyncline, the axial plane of which dips gently to the NE. These limestones overlie a thick series of Toarcian-Aalenian detritic sediments forming the regional aquiclude and the top of the half captive Middle Liasic aquifer. The plateau is limited both in the N and S by strong changes in dip to the vertical of the sedimentary layers (ejective thrusted anticlines), and in the W and E by deep canyons created by major rivers. Therefore the plateau is a totally isolated calcareous compartment, from both a morphologic and a hydrogeologic point of view.
The climate of this region is Mediterranean with an altitude modification: maximum rainfall occurs in winter and in spring, snow cover is not durable but sometimes important, storms are common for dry season in summer. The precipitations comprise only 500 to 700 mm/year (subhumide zone) and the effective evapotranspiration is approximately 400 mm/year, including the losses due to sublimation. The snow coefficient is 60 %. This means that the recharge of the aquifer, occurring almost entirely during snow melting, is limited, but the large bare surfaces of the plateau with typical well developed karst forms (dolines, poljes, dry valleys, holes) improve the infiltration rate (40%). The specific discharge is only 8.1 L/s/km2.
The morphologic peculiarity of this nival karst consist of a succession of small parallel and asymmetric dry valleys forming some "waves". For that reason, the French geomorphologist Couvreur termed these climate controlled features "karst en vagues". The role of wind and snow in the genesis of these forms is predominant. The most of time structure controlled plateau's poljes are quasi inactive today. All kinds of high mountain karren landforms are present on the plateau and prove the great role of snow role in the microforms genesis.
An ancient speleological network with vertical shafts occluded lower down suggest of ancient more humid climatic conditions. U-Th dating indicates ages between 3,200 and 220,000 years, or outside the range of the method (more than 400,000 years). The lateral flow is conducted by an interstrata network, inactive and dry in the upper part, or active and phreatic at the base, near the regional aquiclude, attesting three karstification phases.
The water discharges as typically karstic hillfoot springs, most of the time oversaturated and forming tufas. Large doleritic vertical dykes cut the plateau and form major drainpipes. The physical-chemical and chemical signature of these spring waters is quite different of the signature of other springs of this area, which discharge whether from small local Toarcian-Aalenian aquifers or from the huge semi confined karstic Middle Liasic aquifer. The plateau springs hydrodynamic response is characteristic for an elevated karstic aquifer with rapid flow. The aquifer geometry does not allow important reserves, but the mean discharge from all perennial springs (about 1 m3/s) is a precious resource for the population of this far area of the Atlas Mountains.


Petroleum geology of the Black Sea, 1996,
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Robinson A. G. , Rudat J. H. , Banks C. J. , Wiles R. L. F. ,
The Black Sea comprises two extensional basins formed in a back-arc setting above the northward subducting Tethys Ocean, close to the southern margin of Eurasia. The two basins coalesced late in their post-rift phases in the Pliocene, forming the present single depocentre. The Western Black Sea was initiated in the Aptian, when a part of the Moesian Platform (now the Western Pontides of Turkey) began to rift and move away to the south-east. The Eastern Black Sea probably formed by separation of the Mid-Black Sea High from the Shatsky Ridge during the Palaeocene to Eocene. Subsequent to rifting, the basins were the sites of mainly deep water deposition; only during the Late Miocene was there a major sea-level fall, leading to the development of a relatively shallow lake. Most of the margins of the Black Sea have been extensively modified by Late Eocene to recent compression associated with closure of the Tethys Ocean. Gas chromatography--mass spectrometry and carbon isotope analysis of petroleum and rock extracts suggest that most petroleum occurrences around the Black Sea can be explained by generation from an oil-prone source rock of most probably Late Eocene age (although a wider age range is possible in the basin centres). Burial history modelling and source kitchen mapping indicate that this unit is currently generating both oil and gas in the post-rift basin. A Palaeozoic source rock may have generated gas condensate in the Gulf of Odessa. In Bulgarian waters, the main plays are associated with the development of an Eocene foreland basin (Kamchia Trough) and in extensional structures related to Western Black Sea rifting. The latter continue into the Romanian shelf where there is also potential in rollover anticlines due to gravity sliding of Neogene sediments. In the Gulf of Odessa gas condensate has been discovered in several compressional anticlines and there is potential in older extensional structures. Small gas and oil discoveries around the Sea of Azov point to further potential offshore around the Central Azov High. In offshore Russia and Georgia there are large culminations on the Shatsky Ridge, but these are mainly in deep water and may have poor reservoirs. There are small compressional structures off the northern Turkish coast related to the Pontide deformation; these may include Eocene turbidite reservoirs. The extensional fault blocks of the Andrusov Ridge (Mid-Black Sea High) are seen as having the best potential for large hydrocarbon volumes, but in 2200 m of water

Gypsum karstification in the Middle Miocene Fatha Formation, Mosul area, northern Iraq, 1997,
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Jassim Saad Z. , Jibril Antwanet S. , Numan Nazar M. S. ,
Karstified Middle Miocene sediments are widely exposed in northern Iraq particularly in the area surrounding the city of Mosul. The unit is dominated by gypsum and exposed in thirteen anticlinal structures within the investigated area of about 1600 square kilometers. Synclines, though containing the same sequence, are not karstified due to a Quaternary cover. Karst features were located from air photos: Over 4000 were recorded, the smallest detectable being two meters in diameter. The majority are sinkholes (dolines), developed in gypsum and manifested in the overlying collapsing limestone. They are singular, in lines or clusters. Shafts and karren are fewer in number and are usually developed in uncovered gypsum. Sinkholes are visibly located along fractures and at fracture intersections over gently inclined limestone beds overlying the gypsum. Two karst systems were identified, an active and recent system characteristic of all the anticlinal structures and an older (Pleistocene) fossil karst system characteristic of Alan, Ishkaft, Albu Saif and Hammam structures. The fossil karst system is preserved on remnant elevated old land surfaces and produces characteristic tight undulations in the limestone due to collapse inwards in sinkholes and elongated tunnels formed along a series of sinkholes. The fracture study of anticlinal structures reveals that the mean fracture density per area ranges between 4 and 8 (km/km2) and shows a unimodal character for most of the structures. However the distribution of karst in relation to fractures is bimodal for at least half of the structures with mean values ranging from 4.5 to 11 (km/km2). The fractures in the anticlines are thought to have formed due to folding but some are associated with major lineaments cross cutting the structures, which is reflected in the bimodality and the crude unimodal fracture/karst distribution. Karst features are related to the general fracture pattern but are more localized in densely fractured areas. Karst areas were also found to correlate with lower slope gradient and lower drainage density

Karst terraines in Iran - Examples from Lorestan, 1999,
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Ahmadipour, Mohammad Reza

In Iran karst terrain covers about 13% of the total area. The carbonate rocks belong to the Eocene, Oligocene-Miocene, Miocene, Jurassic and Cretaceous. Most of the carbonate rocks are developed in the basins of Mazindaran and Zagros. The carbonate rocks in the Zone of Zagros, due to the prevailing tectonic activities, have undergone more processes of karstification. About 56 % of all the springs originated from this zone. In Lorestan the Zagros zone consists of a series of parallel anticlines in which, due to the tectonic movements, the rocks have undergone folding and fracturing. The folding and fracturing have created rich ground water reservoirs. The carbonate rocks of Lorestan show all types of karst features such as karren, dolines and caves. The most developed karstic features are seen in the Bangeston group. Most of the springs are discharged either along the lineaments or at the intersection of the lineaments. The chemical analyses of the samples show that they are of bicarbonate type. The drinking water of the city of Khorramabad (capital of Lorestan) is supplied from the karstic springs. In this paper, the karst hydrology of two important regions of Lorestan are considered.


Natural water softening processes by waterfall effects in karst areas, 2000,
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Zhang D. D. , Peart M. , Zhang Y. J. , Zhu A. , Cheng X. ,
The reduction of water hardness, which occurs at waterfalls on rivers in karst areas, is considered to be a result of the waterfall effects. These consist of aeration, jet-flow and low-pressure effects. Waterfall effects bring about two physical changes in river water: an increase in the air-water interface and turbulence. A series of experiments was designed and implemented in order to investigate whether these effects and associated physical changes may cause a reduction of water hardness. From an experiment involving the enlargement of interface area, the plot of air-water interface areas against conductivity revealed that the higher the air-water interface, the more rapidly conductance declines (and Ca2 is precipitated). A bubble producer was designed and used to simulate bubbles that are produced by aeration and low-pressure effects and a faster decline of water hardness was observed at the location with bubbles in this experiment. When a supersaturated solution was passed through a jet-stream producer, a rapid reduction of water hardness and an increase of pH appeared. Field measurements were used to support the laboratory experiments. Work on the Ya He River and at the Dishuiyan Waterfalls revealed that places with aeration had the quickest hardness reduction and the highest average rate of calcite deposition

The influence of tectonic structures on karst flow patterns in karstified limestones and aquitards in the Jura Mountains, Switzerland, 2000,
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Herold T. , Jordan P. , Zwahlen F. ,
The development of karst systems is often assumed to be related to tectonic structures, i. e. joints and faults. However, detailed studies report many of these structures to be indifferent ui even obstacles to karst development. The aim of our study is to present a systematic which helps to explain or even predict whether a specific fault or joint, or a class of such structures are permeable (and therefore likely to be widened to karat conduits) or impermeable. Therefore three extended multi-tracer experiments followed by three months of monitoring were performed at some 95 springs and streams in the Eastern Jura fold-and-thrust belt. In addition, detailed mapping of tectonic and hydrogeological structures, including sinkholes and some 600 springs, has been carried out. The study area is characterised by two large anticlines, which have been affected by pre-fold normal faulting and synorogenic folding and thrusting as well as oblique reactivation of pre-existing faults. Hydrogeologically, two karst aquifers can be distinguished, the lower Mid Jurassic Hauptrogenstein (Dogger Limestone) and the upper Late Jurassic Malm Limestone. Both karst aquifers are confined and separated From each other hy impermeable layers. This study has shown that karst development and groundwater circulation is strongly controlled by tectonic structures resulting in specific meso- to macro-scale anisotropies. Fast long distance transport along fold axes in crest and limb at cas of anticlines is found to be related to extension joints resulting from synorogenic folds. Concentrated lateral drainage of water now from anticline limbs is exclusively related to pre-orogenic normal faults, which have been transtensively reactivated during folding. The same structures are also responsible for the significant groundwater exchange between the lower (inner) and upper (outer) aquifer. This water now, through otherwise impermeable layers, which is reported at several places and in both directions, is suspected to take place in porous calcite fault gouges or fault breccias. Transpressively reactivated normal faults and synorogenic reverse faults, on the other band. are found to have no influence on karst development and groundwater circulation. It is proposed that the systematic found in the Weissenstein area, i.e. that karst conduit development is mainly controlled by extensive or transtensive (reactivated) joints and faults, may also be applied to other tectonically influenced karat regions. Transpressive structures have no significant influence on karst system development and may even act as obstacles

Influence of contaminated Vistula River water on the groundwater entering the Zakrzowek limestone quarry, Cracow region, Poland, 2000,
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Motyka J. , Postawa A. ,
Chemical composition of water inflows in the Zakrzowek quarry, developed in fractured and karstified Upper Jurassic limestones, is controlled by infiltration of polluted water from the Vistula River and by infiltrating meteoric water. The river water TDS value is 2.5 g/dm(3). The quarry waters have 0.6-2.0 g/dm(3) TDS. Highly mineralised waters belong to Cl-Na type. With decreasing TDS the percentage of sulphates, calcium, magnesium and hydrocarbonates increases. This seems to result from various processes including dilution of polluted river water, leaching of aquifer rocks, and ion exchange. The transfer time of river water to the quarry is about 100-120 days. Concentration of contaminants contained in the river water declines during the migration through limestones to the quarry

Results from the Big Spring basin water quality monitoring and demonstration projects, Iowa, USA, 2001,
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Rowden R. D. , Liu H. B. , Libra R. D. ,
Agricultural practices, hydrology, and water quality of the 267-km(2) Big Spring groundwater drainage basin in Clayton County, Iowa, have been monitored since 1981. Land use is agricultural; nitrate-nitrogen (-N) and herbicides are the resulting contaminants in groundwater and surface water. Ordovician Galena Group carbonate rocks comprise the main aquifer in the basin. Recharge to this karstic aquifer is by infiltration, augmented by sinkhole-captured runoff. Groundwater is discharged at Big Spring, where quantity and quality of the discharge are monitored. Monitoring has shown a threefold increase in groundwater nitrate-N concentrations from the 1960s to the early 1980s. The nitrate-N discharged from the basin typically is equivalent to over one-third of the nitrogen fertilizer applied, with larger losses during wetter years. Atrazine is present in groundwater all year; however, contaminant concentrations in the groundwater respond directly to recharge events, and unique chemical signatures of infiltration versus runoff recharge are detectable in the discharge from Big Spring. Education and demonstration efforts have reduced nitrogen fertilizer application rates by one-third since 1981. Relating declines in nitrate and pesticide concentrations to inputs of nitrogen fertilizer and pesticides at Big Spring is problematic. Annual recharge has varied five-fold during monitoring, overshadowing any water-quality improvements resulting from incrementally decreased inputs

Geo-electrical Investigation for Sulfur Prospecting in Teshreen Structure in Northeast Syria, 2002,
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Asfahani Jama, Mohamad Rand,
Electrical and structural characteristics of formations favorable for sulfur occurrences in northeast Syria are described using geo-electrical prospecting methods. Simple (VES) and combined (CVES) Schlumberger vertical electrical soundings and geo-electrical profiling using a Wenner configuration were applied to the Teshreen structure. Six profiles (A, B, C, D, E, and F) at the borders of anticlines, where positive and negative structures are joined and salt formations have a tendency to disappear, were studied. Secondary structures, characterized by high apparent resistivity exceeding 3000 Ohm.m were located on each profile using a Wenner profiling configuration. These secondary structures are demonstrated to be favorable for sulfur prospecting by both drilled wells and vertical electrical soundings. Traditional interpretation of the 84 VES measurments is supported by data from 14 CVES measurments. The CVES technique is a powerful tool, due to its improved resolution of the electrical boundaries. Thicknesses and resistivities of the Lower Al-Fares, Al-Garibeh, and Al-Dibbaneh formations were determined through the interpretation of VES measurments. The same VES measurments were then interpreted using the Pichgin method, whereby all the subsurface tectonic features were determined for depth penetration corresponding to AB/2 = 1000 m. The integration of the first and second VES phases creates a clear picture of the subsurface, including tectonic, geometric, and geo-electrical information. In summary, the sulfur occurrences in the research area are controlled by tectonic paths that are well defined by geo-electrical methods. These diverse geo-electrical methods could be used successfully for sulfur prospecting in similar environments

Paleokarst: cessation and rebirth?, 2003,
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Osborne, R. A. L.

The transformation of active karst into paleokarst by burial, isolation or cessation of process is not necessarily permanent. Paleokarst structures and landforms can be and are exhumed or reactivated, sometimes on numerous occasions. There is not a great deal of similarity between the localities where exhumation and reactivation of paleokarst has been reported. Exhumation and reactivation however have not been reported in many karsts that are similar to those where they have been reported. Exhumation and reactivation appears to be favoured in four situations: - the margins of sedimentary basins overlying grand unconformities, the axes of anticlines, narrow steeply-dipping impounded karsts and where paleokarst fill contains unstable minerals. Six processes are principally responsible for exhumation and reactivation: - per-ascensum speleogenesis, eustatic sea level changes, paragenesis, high density speleogenesis, glaciation, and large-scale meteoric speleogenesis. On some occasions karst landforms, particularly caves or segments of caves, may survive intact and unfilled for geologically significant periods of time. These may be completely isolated from the surface environment, or become reactivated by entrance formation due to breakdown, surface lowering or headward erosion. The intersection and reactivation of ancient open cavities and of exhumed cavities by “modern” caves may be much more common than is currently recognised. If caves have histories as long and as complex as the karsts in which they are developed then many “modern” caves will be composite features composed of interconnected “modern”, relict and exhumed cavities excavated at different times by different processes. Unravelling these histories is the new challenge facing cave science. It will require caves to be studied in a much more detailed, thorough and systematic manner and will also require the application of new technologies in surveying, analysis and dating


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