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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 peat is decomposed matter, mainly vegetable [16].?

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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 earthquake (Keyword) returned 43 results for the whole karstbase:
Showing 16 to 30 of 43
Paleoseismic phenomena in karst terrains in Bulgaria and Morocco, 2003, Angelova Dora, Belfoul M'hamed Alaeddin, Bouzid Sophia, Filahi Mustapha, Faik Farid

During the recent years there has been a growing interest in recording and investigating the effects of paleoseismic events in surface and underground karst in almost all countries. Karst represents a reliable reference marker for understanding the potential seismicity in regions with instrumentally established low to moderate seismicity. The karst errains in Bulgaria and Morocco occupy considerable areas. The disturbances in surface and underground karst had usually been provoked by catastrophic one-act events or by repeatedly activated movements by earthquakes. The catastrophic seismic events had disturbed the naturally interrelated karst ecosystems and were the reason for rejuvenation, reactivation or attenuation of karst processes. The natural surface and underground relief had been partially or entirely destroyed; a new type of relief had been formed; the geological environment had been disturbed; changes occurred in the flowrate and direction of surface and underground karst water; wetlands of the gravitation type had been formed; natural caves, local grabens, rock-falls and landslides collapsed partially or entirely and terrains were subjected to subsidence and destruction; the ecological balance in urbanized territories had been disturbed. The present work considers the different types of paleoseismic phenomena in the karst terrains in Bulgaria and Morocco. Recommendations are given for the protection of these areas.


Speleothem rupture in karst: tectonic or climatic origin? U-Th dating of rupture events in Salamandre Cave (Gard, southeastern France), 2004, Ponsbranch, Hamelin B. , Brulhet J. , Bruxelles L. ,
Caves are relatively protected from the main external erosional factors. Therefore, they constitute potentially reliable places for long-term conservation of continental history. Moreover their secondary carbonated deposits, the speleothems, can be dated precisely on the 0-500 ka time-scale using U-series isotopes measured by thermo-ionisation mass spectrometry (TIMS). Tectonic events (tectonic displacements and earthquakes) may change cave morphology and induce speleothem breaking or displacement as has been shown by previous studies performed mainly in Italy [Forti et Postpischl, 1984; Postpischl et al., 1991 for example]. Nevertheless, collapses of speleothems observed today in caves are difficult to interpret as their origin may be linked to several other natural processes. We studied the Aven de la Salamandre cave located in southeastern France (Gard), an area between the Cevennes fault and the Nimes fault, where evidence of Quaternary vertical movements was previously described. However, this region is not considered to be a seismic active zone. The Aven de la Salamandre cave is characterized by numerous broken speleothems. Some of them are very large and a lot of them are covered by growth of new calcite or new speleothem generation. We report here 13 TIMS U/Th analysis performed on two broken speleothems recovered by second generation calcite growth. Dating results are discussed through time corrections due to detrital content of calcite. In the first sequence, a 7 0.35 ka fracture event is identified. In the second sequence, the age of the breakdown is between 1.1 0.1 and 6.3 2 ka. These events could thus be contemporary. Hypotheses for the origin of this fracture event are presented and discussed: (i) karstic catastrophic event due to intense climatic changes or to cavity collapse (break down of hanging wall, gravity, landslide...); (ii) co-seismic ruptures. The first conclusion of this study is that these collapse episodes in the Aven de la Salamandre cave cannot be due to the direct effect of an earthquake or climatic event. Only indirect effects of flooding (by mobilization of the argillaceous components of the floor and consecutive destabilization of the speleothems growing upon it) or earthquake effects (more likely by local effects than by wave front passage) are privileged. By comparing our dating with regional destructive known events (in other karsts, in cliffs and scarps), dated by relative chronology, we are lead to propose a regional generalized event precisely dated here at 7 ka. This second conclusion doesn't contradict the presence of unbroken speleothems older than 100 ka found in other caves in the neighborhood as local effects is one of the predominant factors relative to speleothem stability. As a final conclusion, this paper promotes the use of speleothems as reliable datable tools for assessing regional stability problems (sensitivity to seismic hazards, to destructive intense climatic events...) as is done for paleoclimatic reconstruction

Glacial causes of damage and difficulties to use speleothems as palaeoseismic indicators, 2004, Gilli E,
Fractures that affect cave speleothems have often been described as the result of earthquakes and their use in paleoseismic studies is more and more frequent. Nevertheless observations during and after earthquakes, modeling and laboratory experiments indicate that, except for some slender speleothems, the cave formations usually do not break during an earthquake. New observations in caves in France and Slovenia reveal other mechanisms as the creeping of ice or clay filling that easily explain most of the breaks. (C) 2004 Lavoisier SAS. All rights reserved

Hazards caused by natural and anthropogenic changes of catchment area in karst, 2004, Bonacci O,
Determination of the catchment area is the starting point in most hydrological analyses. It serves as a basis for many hydrological and water resources management calculations. The catchment boundaries and areas in karst regions are often fragmented and not accurately known. They can change over time due to natural and anthropogenic causes. Natural and man-made processes cause changes of catchment area on different time and space scales. Human intervention, especially construction of dams and reservoirs, as well as interbasin water transfer through long tunnels and pipelines can introduce instantaneous, definite and hazardous change. This paper presents seven examples of natural and anthropogenic factors which influenced changes of catchment area in the Dinaric karst: 1) Closing of the Obod Estavelle in the Fatniceko polje; 2) Operation of the Zaku6ac hydroelectric power plant on the Cetina River; 3) Problems caused by Salakovac Reservoir; 4) Catastrophic flooding in the Cetinje Polje; 5) Regulation and canalization of the Trebisnjica River; 6) Building of the underground hydroelectric power plant Ombla; 7) An earthquake in Southern Croatia and Western Herzegovina

Natural Speleothem Damage in Postojnska Jama, Slovenia, Caused by Glacial Cave Ice? A First Assessment, 2004, Kempe, Stephan

Natural speleothem damage has been known from Postojnska jama for a long time. Schaffenrath was the first to depict broken and leaning stalagmites on his pictures from the interior of the cave. Hohenwart analysed some of these damages, clearly excluding rock fall or earthquakes as a cause. Here the author discusses the possibilities, which could cause natural speleothem breakage in general. The most promising cause is cave ice. It must have formed in caves during glacial maxima when permafrost spread throughout northern, eastern and central Europe. Consequently cave ice could be the most prominent factor in explaining non-recent speleothem damage. Next some of the historically known flowstone breakages from Postojnska jama are presented. These are discussed in view of cave ice and an ad hoc model for the genesis is given. In the side passages Pisani rov and Brezimenski rov there are masses of broken stalagmites and stalactites and speleothem fragments in precarious positions. Cave ice offers an overall process to explain these observations. Thus it is suggested that all or parts of the Postojnska jama were filled with ice during the Last and earlier Glacials. If accepting speleothem damage as a consequence of glacial cave ice, then it should be possible to use it as a marker facies for the extent of the zero temperature line during the various glacials.


Review on the use of natural cave speleothems as palaeoseismic or neotectonics indicators, 2005, Gilli E,
Collapses that affect cave speleothems have frequently been attributed to earthquakes, although this has not been proved. Observations after an earthquake and laboratory tests indicate that only slender speleothems break under coseismic solicitation. Other causes as subsidence, decompression and creeping of ice or cave sediments explain most of the breaks. Tectonics is also a major cause of speleothems breakages and it is possible to detect minute movements of faults. It seems possible to make the difference between brutal coseismic movements and aseismic slow ones. However, the interpretation is often difficult, as the damage can also be caused by gravity tectonics or glacitectonics. To cite this article: E. Gilli, C. R. Geoscience 337 (2005)

Dating large infrequent earthquakes by damaged cave deposits, 2005, Kagan Elisa J. , Agnon Amotz, Barmatthews Miryam, Ayalon Avner,
The long-term recurrence patterns of past earthquakes are of considerable consequence for hazard assessments, and have implications for earthquake physics. We introduce a rigorously dated record of earthquakes from an extensive number of well-preserved preseismic and postseismic precipitates from caves located off the Dead Sea transform. We dated events directly at the paleoseismic contact by means of a novel correlation method with the oxygen isotope record of the speleothems recovered in one of the caves. Within the 185 k.y. covered, we dated 38 seismite samples. These stem from 13-18 earthquakes with a mean recurrence interval of [~]10-14 k.y. We show that the deformational events dated in the study caves complement independent near-fault paleoseismic records by temporal correlation with the earthquakes recorded therein. This opens up a significant new avenue of earthquake research that will provide precise dating and observational constraints on large infrequent earthquakes

Variation of palaeostress patterns along the Oriente transform wrench corridor, Cuba: significance for Neogene-Quaternary tectonics of the Caribbean realm, 2005, Rojasagramonte Y. , Neubauer F. , Handler R. , Garciadelgado D. E. , Friedl G. , Gadodamas R. ,
In this study, we address the late Miocene to Recent tectonic evolution of the North Caribbean (Oriente) Transform Wrench Corridor in the southern Sierra Maestra mountain range, SE Cuba. The region has been affected by historical earthquakes and shows many features of brittle deformation in late Miocene to Pleistocene reef and other shallow water deposits as well as in pre-Neogene, late Cretaceous to Eocene basement rocks. These late Miocene to Quaternary rocks are faulted, fractured, and contain calcite- and karst-filled extension gashes. Type and orientation of the principal normal palaeostress vary along strike in accordance with observations of large-scale submarine structures at the south-eastern Cuban margin. Initial N-S extension is correlated with a transtensional regime associated with the fault, later reactivated by sinistral and/or dextral shear, mainly along E-W-oriented strike-slip faults. Sinistral shear predominated and recorded similar kinematics as historical earthquakes in the Santiago region. We correlate palaeostress changes with the kinematic evolution along the boundary between the North American and Caribbean plates. Three different tectonic regimes were distinguished for the Oriente transform wrench corridor (OTWC): compression from late Eocene-Oligocene, transtension from late Oligocene to Miocene (?) (D-1), and transpression from Pliocene to Present (D-2-D-4), when this fault became a transform system. Furthermore, present-day structures vary along strike of the Oriente transform wrench corridor (OTWC) on the south-eastern Cuban coast, with dominantly transpressional/compressional and strike-slip structures in the east and transtension in the west. The focal mechanisms of historical earthquakes are in agreement with the dominant ENE-WSW transpressional structures found on land. (C) 2004 Elsevier B.V. All rights reserved

Tectonic sights of the Pivka basin, 2005, Š, Ebela S.

The important regional thrust called Snežnik thrust, that divides the Snežnik thrust sheet from the parautochthon of the Komen thrust sheet, runs through the Pivka basin. A tectonic window near Knežak is proof of older thrusting deformations. The landscape is cut by numerous younger faults among which the most important are Raša, Predjama and Selce faults. The area of Upper Pivka is tectonically quite active, which is shown by earthquakes in recent years. It looks as if the most active is the Raša fault or one of its northern parallel faults, for example Šembije fault or maybe Selce fault. Karst intermittent lakes of Upper Pivka are developed in Upper Cretaceous limestones. The lakes are situated 0.5-4.0 km NE from the Snežnik thrust. Most of the lakes are situated along the Selce fault.


The Earth Has a Future, 2006, Dutch Si,
An alternative to visualizing geologic time by looking into the past is to look into the future. Even geologically short future time scales completely outstrip our ability to forecast changes in human society, whereas most geologic changes in the same time will be modest. Many events that are infrequent on a human time scale, such as earthquakes and volcanic eruptions, become commonplace on longer time scales, and events that have not occurred in recorded history, such as major ice ages, large meteor impacts, giant pyroclastic eruptions, or collapses of Hawaiian shield volcanoes, become almost inevitable in a million years

The very-broad-band long-base tiltmeters of Grotta Gigante (Trieste, Italy): Secular term tilting and the great Sumatra-Andaman islands earthquake of December 26, 2004, 2006, Braitenberg C, Romeo G, Taccetti Q, Nagy I,
The horizontal pendulums of the Grotta Gigante (Giant Cave) in the Trieste Karst, are long-base tiltmeters with Zollner type suspension. The instruments have been continuously recording tilt and shear in the Grotta Gigante since the date of their installation by Prof. Antonio Marussi in 1966. Their setup has been completely overhauled several times since installation, restricting the interruptions of the measurements though to a minimum. The continuous recordings, apart from some interruptions, cover thus almost 40 years of measurements, producing a very noticeable long-term tiltmeter record of crustal deformation. The original recording system, still in function, was photographic with a mechanical timing and paper-advancing system, which has never given any problems at all, as it is very stable and not vulnerable by external factors as high humidity, problems in power supply, lightning or similar. In December 2003 a new recording system was installed, based on a solid-state acquisition system intercepting a laser light reflected from a mirror mounted on the horizontal pendulum beam. The sampling rate is 30 Hz, which turns the long-base instrument to a very-broad-band tiltmeter, apt to record the tilt signal on a broad-band of frequencies, ranging from secular deformation rate through the earth tides to seismic waves. Here we describe the acquisition system and present two endline members of the instrumental observation, the up to date long-term recording, and the observation of the great Sumatra-Andaman Islands earthquake of December 26, 2004, seismic moment magnitude Mw = 9.1-9.3 [Lay, T., Kanamori, H., Ammon, C.J., Nettles, M., Ward, S.N., Aster, R.C., Beck, S.L., Bilek, S.L., Brudzinski, M.L., Butler, R., DeShon, H.R., Ekstrom, G., Satake, K., Sipkin, S., 2005. The Great Sumatra-Andaman Earthquake of 26 December 2004. Science. 308, 1127-1133.]. The secular-term observations indicate an average tilting over the last four decades towards NW of 23.4 nrad/year. We find evidences that this tilting is regional and has been going on since at least 125 ka. The recent earthquake of December 26, 2004 was well recorded by the pendulums. We show that the free oscillation modes were activated, including the lowest modes as e.g. 0T2, 0T3, 0T4, 0T5 and 2S1, 0S3, 0S4, 1S2

Tectonic-hydrothermal brecciation associated with calcite precipitation and permeability destruction in Mississippian carbonate reservoirs, Montana and Wyoming , 2006, Katz D. A. , Eberli G. P. , Swart P. K. , Smith Jr. L. B.

The Mississippian Madison Formation contains abundant fracture zones and breccias that are hydrothermal in origin based on their morphology, distribution, and geochemical signature. The hydrothermal activity is related to crustal shortening during the Laramide orogeny. Brecciation is accompanied by dedolomitization, late-stage calcite precipitation, and porosity occlusion, especially in outcrop dolomites. The tectonic-hydrothermal late-stage calcite reduces permeability in outcrops and, potentially, high-quality subsurface reservoir rocks of the subsurface Madison Formation, Bighorn Basin. The reduction of permeability and porosity is increased along the margins of the Bighorn Basin but not predictable at outcrop scale. The destruction of porosity and permeability by hydrothermal activity in the Madison Formation is unique in comparison to studies that document enhanced porosity and permeability and invoke hydrothermal dolomitization models. Hydrothermal breccias from the Owl Creek thrust sheet are classified into four categories based on fracture density, calcite volume, and clast orientation. Shattered breccias dominate the leading edge of the tip of the Owl Creek thrust sheet in the eastern Owl Creek Mountains, where tectonic deformation is greatest, whereas fracture, mosaic, and chaotic breccias occur throughout the Bighorn Basin. The breccias are healed by calcite cements with d18O values ranging between _26.5 and _15.1xPeedee belemnite (PDB), indicating that the cements were derived from isotopically depleted fluids with elevated temperatures. In the chaotic and mosaic breccia types, large rotated and angular clasts of the host rock float in the matrix of coarse and nonzoned late-stage calcite. This appearance, combined with similar d18O values across even large calcite veins, indicates that the calcite precipitated rapidly after brecciation. Values for d13C(_5–12xPDB) from the frontal part of the Owl Creek thrust sheet indicate equilibrium between methane and CO2-bearing fluids at about 180jC. Fluid inclusions from the eastern basin margin show that these cements are in equilibrium with fluids having minimum temperatures between 120 and 140jC and formed from relatively low-salinity fluids, less than 5 wt.% NaCl. Strontium isotope ratios of these hydrothermal fluids are more radiogenic than proposed values for Mississippian seawater, suggesting that the fluids mixed with felsic-rich basement before migrating vertically into the Madison Formation. We envisage that the tectonic-hydrothermal late-stage calcitecemented breccias and fractures originated from undersaturated meteoric ground waters that migrated into the burial environment while dissolving and incorporating Ca2+ and CO3 2_ and radiogenic Sr from the dissolution of the surrounding carbonates and the felsic basement, respectively. In the burial environment, these fluids were heated and mixed with hypersaline brines from deeply buried parts of the basement. Expulsion of these fluids along basementrooted thrust faults into the overlying strata, including the Madison Formation, occurred most likely during shortening episodes of the Laramide orogeny by earthquake-induced rupturing of the host rock. The fluids were injected forcefully and in an explosive manner into the Madison Formation, causing brecciation and fracturing of the host rock, whereas the subsequent and sudden decrease in the partial pressure of CO2 caused the rapid precipitation of calcite cements. The explosive nature of hydrothermal fluid migration ultimately produces heterogeneities in reservoir-quality carbonates. In general, flow units in the Madison Formation are related to sequence boundaries, which create vertical subdivisions in the porous dolomite. The late-stage calcite cement surrounds hydrothermal breccia clasts and invades the dolomite, reducing porosity and permeability of the reservoir-quality rock. As a consequence, horizontal flow barriers and compartments are established that are locally unpredictable in their location and extent and regionally predictable along the margins of the Bighorn Basin. 


SURFACE VERSUS UNDERGROUND MEASUREMENTS OF ACTIVE TECTONIC DISPLACEMENTS DETECTED WITH TM 71 EXTENSOMETERS IN WESTERN SLOVENIA, 2009, Gosar Andrej, ebela Stanka, Ko?k Blahoslav & Stemberk Josef
The tectonic setting of W Slovenia is characterised by NW-SE trending dextral strike-slip fault systems and moderate seis-micity. Monitoring of tectonic movements along five presum-ably active faults or in their vicinity using TM 71 extensom-eters was set up in 2004. In five years of monitoring some clear trends of displacement were established. The morphologically most prominent fault in W Slovenia is Idrija Fault having a to-tal length of more than 120 km. The average lateral displace-ment measured along a crack in its inner fault zone in U?ja valley was 0.26 mm/year. Short-term rates were even greater and reached 0.54 mm/year. Raa Fault monitoring site at the foot of Vrem?ica Mt. established first an average uplift of SW block for 0.16 mm/year and left-lateral displacement of 0.16 mm/ year. It was followed by down-slip of the same block at the rate of 0.37 mm/year. In Postojnska Jama two instruments, 260 m apart, were installed at the fault zone, which extends about 1 km northeast from Predjama Fault. We detect small tectonic deformations, dextral horizontal movement of 0.05 mm in 5 years for Postojna 1 and extension of 0.03 mm in 5 years for Postojna 2. Both devices recorded similar reactions to some earthquakes with magnitude range 3.1-5.2 and epicentral distance of 12-95 km. The amplitude of individual peaks is in the order of 0.08 mm. The monitoring at Knea Fault started at the end of 2006. In two years clear oblique displacement was established with left-lateral rate of 0.06 mm/year and uplift of SW block for 0.06 mm/year. Monitoring in Poloka Jama situated in vicinity of the Ravne Fault started in 2008. Preliminary results show 0.08 mm of horizontal displacement between two limestone beds. Established displacements proved the active tectonic movement of all monitored faults. Observed deforma-tion rates can be compared with the regional deformation rate in W Slovenia established from GPS measurement, which is in the order of 2 mm/year. Keywords: micro-tectonic displacements, 3D monitoring, TM 71 extensometer, Idrija Fault, Raa Fault, Knea Fault, Predjama Fault, Ravne Fault, Slovenia.

High-precision 238U234U230Th disequilibrium dating of the recent past: a review, 2009, Zhao Jianxin, Yu Kefu, Feng Yuexing

Although it was demonstrated 20 years ago that mass spectrometric U–Th methods are capable of highprecision dating of young corals, the use of this approach to decipher recent environmental, climatic and archaeological records is still restricted and its potential has not yet been widely recognised. U–Th methods are typically used to determine the ages of carbonate materials such as speleothem and coral. Dating young carbonates of this sort is challenging. Their extremely low 230Th content necessitates stricter instrumental and laboratory conditions than those required for dating older samples. Moreover, analyses must be corrected for the presence of non-radiogenic 230Th, which is proportionally far more significant than in older samples. Nevertheless, 2s precisions of around _1–10 years are readily achievable for pristine coral samples dating from the last 500 years. Although the range of analytical precisions for speleothems may vary more widely depending on U concentrations and levels of nonradiogenic 230Th correction, published studies reveal 2s precisions of around _10–80 years for typical speleothems. This paper demonstrates how the U–Th method may be applied to establish the causes of recent coral mortality, to determine the recurrence interval of extreme wave events, to investigate earthquake frequency and neotectonic uplift, to reconstruct recent climatic history, and to understand settlement patterns and sociopolitical changes in Polynesia prior to European contact.


SPATIAL AND TEMPORAL HYDROCHEMICAL VARIATIONS OF THE SPRING-FED TRAVERTINE DEPOSITING STREAM IN THE HUANGLONG RAVINE, SICHUAN, SW CHINA, 2010, Wang H. , Liu Z. , Zhang J. , Sun H. , An D. , Fu R. , Wang X.
Automatic hydrochemical logging and in situ titration combined with laboratory analysis were used to understand the spatial and temporal hydrochemical variations of the spring-fed, travertine-depositing stream in celebrated Huanglong Ravine, Sichuan, SW China. This is essential for protection of the Huanglong World Natural Heritage travertine landscape. It was found that the deposition of travertine was due to very strong CO2 degassing from the water, leading to decrease in pCO2 and specific conductivity (SpC), and increase in pH and SIc downstream from the Spring. However, regular downstream hydrochemical evolution was interrupted by dilution with snowmelt water and by renewed CO2 from some downstream springs. The chemistry of Huanglong Spring itself was stable at a diurnal scale though it was altered by the great Wenchuan earthquake of May 12 2008. However, in spring-fed pools downstream, pCO2 and SpC were lower, and pH and SIc were higher in daytime than at night, which indicates that the deposition of travertine was faster during the daylight hours. This was due to the combined e?ects of higher water tempera-tures and higher aquatic algae photosynthesis. In addition, it was found that the phosphate concentration in the stream in-creased remarkably downstream in the tourist midseason, in-dicating water pollution by tourism activities. ?e increase of phosphate (an inhibitor of calcite precipitation) may be one of the reasons for the decrease in travertine deposition rates and accelerated propagation of discoloration by diatoms during the past decades, which needs to be given more comprehensive study and tackled in future for the protection of these world famous travertine deposits.Keywords: hydrochemical var

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