| |
Records |
Links |
|
Author |
Ladouche, B.; Luc, A.; Nathalie, D. |
|
| |
Title |
Chemical and isotopic investigation of rainwater in Southern France (1996–2002): Potential use as input signal for karst functioning investigation |
Type |
Journal Article |
| |
Year |
2009 |
Publication |
Journal of Hydrology |
Abbreviated Journal |
|
|
| |
Volume |
367 |
Issue  |
1-2 |
Pages |
150-164 |
|
| |
Keywords |
|
|
| |
Abstract |
|
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-1694 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
THL @ luqianxue.zhang @ Ladouche2009 |
Serial |
58 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Herut, B.; Starinsky, A.; Katz, A. |
|
| |
Title |
Strontium in rainwater from Israel: sources, isotopes and chemistry |
Type |
Journal Article |
| |
Year |
1993 |
Publication |
Earth and Planetary Science Letters |
Abbreviated Journal |
|
|
| |
Volume |
120 |
Issue |
1-2 |
Pages |
77-84 |
|
| |
Keywords |
|
|
| |
Abstract |
Eighteen ram samples from Israel have been analyzed for their chemical composmon and S7Sr/S6Sr ratios The Sr-Isotoplc rahos lie In the range 0 7078 and 0 7092, and the Sr concentrations vary from 1 × 10 -4 to 9 x 10 4 meq Sr/l.
Soluble salts in rainwater are inherited from three major natural sources, seaspray, Recent marine minerals and mineral dust eroded from rock outcrops and soft A mixing model is formulated to apply the chemical composmon of rain (CI and Sr 2+) and ~ts isotopic 87Sr/S6Sr ratio, for the identification and est~mahon of the Sr sources.
All the samples fall within the m~xing space predicted by the model for the three end members mentioned above The data indicate that the most important non-seaspray source contributing d~ssolved salts to the rams m Israel comprises a mixture of Senoman to Eocene chalk (and its weathering products) and Recent marine minerals, from local and imported sources.
Most of the samples (67%) contain 50% or more non-seaspray Sr 0 e, Sr dissolved from dust or Recent marine minerals), whereas 56% of the samples display 87Sr/86Sr ratios lower than 0 7090. The rest represent mixtures of seaspray and Recent marine minerals. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Elsevier |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
|
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
THL @ luqianxue.zhang @ herut1993strontium |
Serial |
95 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Hanshaw, B.B.; Back, W. |
|
| |
Title |
Major geochemical processes in the evolution of carbonate—Aquifer systems |
Type |
Journal Article |
| |
Year |
1979 |
Publication |
Journal of Hydrology |
Abbreviated Journal |
|
|
| |
Volume |
43 |
Issue |
1 |
Pages |
287-312 |
|
| |
Keywords |
|
|
| |
Abstract |
As a result of recent advances by carbonate petrologists and geochemists, hydrologists are provided with new insights into the origin and explanation of many aquifer characteristics and hydrologic phenomena. Some major advances include the recognition that: (1) most carbonate sediments are of biological origin; (2) they have a strong bimodal size-distribution; and (3) they originate in warm shallow seas. Although near-surface ocean water is oversaturated with respect to calcite, aragonite, dolomite and magnesite, the magnesium-hydration barrier effectively prevents either the organic or inorganic formation of dolomite and magnesite. Therefore, calcareous plants and animals produce only calcite and aragonite in hard parts of their bodies. Most carbonate aquifers that are composed of sand-size material have a high initial porosity; the sand grains that formed these aquifers originated primarily as small shells, broken shell fragments of larger invertebrates, or as chemically precipitated oolites. Carbonate rocks that originated as fine-grained muds were initially composed primarily of aragonite needles precipitated by algae and have extremely low permeability that requires fracturing and dissolution to develop into aquifers. Upon first emergence, most sand beds and reefs are good aquifers; on the other hand, the clay-sized carbonate material initially has high porosity but low permeability, a poor aquifer property. Without early fracture development in response to influences of tectonic activity these calcilutites would not begin to develop into aquifers. As a result of selective dissolution, inversion of the metastable aragonite to calcite, and recrystallization, the porosity is collected into larger void spaces, which may not change the overall porosity, but greatly increases permeability. Another major process which redistributes porosity and permeability in carbonates is dolomitization, which occurs in a variety of environments. These environments include back-reefs, where reflux dolomites may form, highly alkaline, on-shore and continental lakes, and sabkha flats; these dolomites are typically associated with evaporite minerals. However, these processes cannot account for most of the regionally extensive dolomites in the geologic record. A major environment of regional dolomitization is in the mixing zone (zone of dispersion) where profound changes in mineralogy and redistribution of porosity and permeability occur from the time of early emergence and continuing through the time when the rocks are well-developed aquifers. The reactions and processes, in response to mixing waters of differing chemical composition, include dissolution and precipitation of carbonate minerals in addition to dolomitization. An important control on permeability distribution in a mature aquifer system is the solution of dolomite with concomitant precipitation of calcite in response to gypsum dissolution (dedolomitization). Predictive models developed by mass-transfer calculations demonstrate the controlling reactions in aquifer systems through the constraints of mass balance and chemical equilibrium. An understanding of the origin, chemistry, mineralogy and environments of deposition and accumulation of carbonate minerals together with a comprehension of diagenetic processes that convert the sediments to rocks and geochemical, tectonic and hydrologic phenomena that create voids are important to hydrologists. With this knowledge, hydrologists are better able to predict porosity and permeability distribution in order to manage efficiently a carbonate—aquifer system. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-1694 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
THL @ christoph.kuells @ Hanshaw1979 |
Serial |
26 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Cardenal, J.; Benavente, J.; Cruz-Sanjulián, J.J. |
|
| |
Title |
Chemical evolution of groundwater in Triassic gypsum-bearing carbonate aquifers (Las Alpujarras, southern Spain) |
Type |
Journal Article |
| |
Year |
1994 |
Publication |
Journal of Hydrology |
Abbreviated Journal |
|
|
| |
Volume |
161 |
Issue |
1 |
Pages |
3-30 |
|
| |
Keywords |
|
|
| |
Abstract |
A hydrochemical study employing modelling techniques, was carried out using samples taken at 65 points (springs and wells) in Triassic carbonate aquifers (Lújar-Gádor Unit, Alpujárride Complex, Betic Cordillera). These aquifers are made up of limestones and dolomites with some gypsum scattered or interbedded. Though the area is semi-arid, recharge is relatively high because of their mountainous nature. The carbonate rocks contain dense microfissuration; the groundwater flow regime is predominantly diffuse. The karstic forms are in general poorly developed. Two main hydrochemical processes have been identified in these aquifers. One is incongruent dissolution of dolomite that determines the chemical composition of the less mineralised water. The other is dedolomitisation (dolomite dissolution together with calcite precipitation caused by dissolution of gypsum), which becomes predominant when the flow encounters interbedded gypsum. This reaction is also frequently associated with low temperature thermalism, and can play a part in more intense local karstification (cavities, sinkholes, high transmisivity in wells) observed in the sectors of these aquifers where gypsum is more abundant. A reaction path model has been used to simulate the geochemical processes through a hypothetical aquifer (with similar lithology to the Alpujárride carbonate aquifers). Successive stages of evolution through the carbonate sequence, represented by different saturation states with respect to calcite, dolomite gypsum and CO2, have been modelled and then compared with the field data. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0022-1694 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
THL @ christoph.kuells @ Cardenal1994 |
Serial |
18 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
El Yaouti, F.; El Mandour, A.; Khattach, D.; Benavente, J.; Kaufmann, O. |
|
| |
Title |
Salinization processes in the unconfined aquifer of Bou-Areg (NE Morocco): A geostatistical, geochemical, and tomographic study |
Type |
Journal Article |
| |
Year |
2009 |
Publication |
Applied Geochemistry |
Abbreviated Journal |
|
|
| |
Volume |
24 |
Issue |
1 |
Pages |
16-31 |
|
| |
Keywords |
|
|
| |
Abstract |
Hydrogeological and geochemical data, in conjunction with the results of an electrical imaging tomographic survey, were examined to determine the main factors and mechanisms controlling the groundwater chemistry and salinity of the unconfined aquifer of Bou-Areg, on the Mediterranean coast of NE Morocco. In addition, statistical and geochemical interpretation methods were used to identify the distribution of the salinity. Multivariate statistical analysis (cluster and principal component factors) revealed the main sources of contamination. Groups A, B, and C in the cluster analysis and Factors 1–3 (Factor 1: CE, Cl−, K+, SO42-, and Mg2+; Factor 2: Ca2+, HCO3-, and pH; Factor 3: NO3-) represent the ‘signature’ of seawater intrusion in the coastal zone, the influence of marly-gypsum outcrops in the upstream zone, and anthropogenic sources, respectively. The ionic delta, the ionic ratio, the saturation index, and Stuyfzand’s method were applied to evaluate geochemical processes. The results obtained indicate, on the one hand, the phenomenon of salinization in both the coastal and the upstream zones, and on the other, the dilution of groundwater by recharge. Cation exchange is shown to modify the concentration of ions in groundwater. Locally, with respect to salinization processes in the coastal zone, the results of electrical imaging tomography show that salinity increases both with depth and laterally inland from the coastline, due to seawater intrusion. |
|
| |
Address |
|
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0883-2927 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
|
Approved |
no |
|
| |
Call Number |
THL @ christoph.kuells @ ElYaouti2009 |
Serial |
21 |
|
| Permanent link to this record |
