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11.
The Ganga–Mahawa sub‐basin, which has an area of 1280 km2 forms the western part of the Central Ganga Plain in the Moradabad and Badaun districts of western Uttar Pradesh, India. The Bundelkhand granite forms the basement complex, overlain unconformably by the upper Vindhyan sequence, which is further overlain by the Neogene (Middle and Upper) Siwaliks and finally by Quaternary alluvium. Four geomorphological units, the Varanasi older alluvial plain, Aligarh older alluvial plain, terrace zones and the Ganga recent floodplain, abandoned channels, channel scars and meander scars represent various landforms. The hydrogeological cross‐sections indicate the occurrence of a single aquifer down to 120 m. Some influent seepage from the River Ganga could be seen around Gangeswari, but the rest of the River Ganga is effluent. Groundwater‐flow modelling was carried out to assess the degree of Ganga river and aquifer interaction. The River Ganga marks the western boundary; boundaries to the northeast and southeast are set as fixed heads to simulate lateral inflow into and outflow from the sub‐basin respectively. The eastern boundary is simulated as a no‐flow condition. The Mahawa and Badmar rivers are considered to be effluent. The area modelled is covered by a grid of 34 rows×46 columns with three layers, viz., an unconfined aquifer, an aquitard which is underlain by a semi‐confined to confined aquifer. The permeability distribution was inferred from morphometric analysis and pumping tests. Natural recharge due to monsoon rainfall forms the main input. The River Ganga stage data at Ahar, Naora and Ramghat has been used for assigning surface water levels and river bed elevations in the model. Abstraction from all existing deep and shallow tube wells has been assigned as output at various cells. A steady state flow simulation was carried out and calibrated against the June 1986 water level; subsequent transient conditions were calibrated up to May 1995. The computed groundwater balance was comparable to that estimated from field investigations. The aquifer modelling study has attempted to integrate all available information and provided a tool that could be used for predictive simulation. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
12.
Jay Krishna THAKUR Prafull SINGH Sudhir Kumar SINGH Bijendra BHAGHEL 《《地质学报》英文版》2013,87(5):1421-1433
The aim of the present study is to locate and decipher the groundwater quality,types,and hydrogeochemical reactions,which are responsible for elevated concentration of fluoride in the Chhindwara district in Madhya Pradesh,India.Groundwater samples,quality data and other ancillary information were collected for 26 villages in the Chhindwara District,M.P.India during May 2006.The saturation index was computed for the selected samples in the region,which suggest that generally most of the minerals are saturated with respect to water.The concentration of fluoride in the region varies from 0.6 to 4.74 mg/l,which is much higher as per the national and international water quality standards.The study also reveals that the fluoride bearing rock formations are the main source of the higher concentration of fluoride in groundwater along with the conjuncture of land use change.Moreover,the area is a hard rock terrain and consists of fractured granites and amygdaloidal and highly jointed compact basalt acting as good aquifer,which is probably enriching the high content of fluoride in groundwater.High concentration of fluoride is found in deeper level of groundwater and it is possible due to rock-water interaction,which requires further detailed investigation.The highly alkaline conditions indicate fluorite dissolution,which works as a major process for higher concentration of fluoride in the study area.The results of this study will ultimately help in the identification of risk areas and taking measures to mitigate negative impacts related to fluoride pollution and toxicity. 相似文献
13.
S. C. Khosla M. L. Nagori S. R. Jakhar A. S. Rathore 《Journal of the Geological Society of India》2009,73(5):724-732
Except for the east coast of Andhra Pradesh, the Deccan Inter-trappean sedimentary beds of Peninsular India have been long
known to yield non-marine microfauna, mainly ostracods. These have been extensively described from different localities of
Madhya Pradesh, Maharashtra, Karnataka, Andhra Pradesh, Gujarat and Rajasthan states. Occurrence of mixed microfaunal association
of marine, brackish water and non-marine foraminifers and ostracods is being recorded from these beds from Jhilmili, Chhindwara
district, Madhya Pradesh. It comprises at least two or more planktonic foraminifer species, and one brackish water and 17
non-marine ostracod species. The brackish water ostracod, Neocyprideis raoi (Jain, 1978) has been previously recorded in great profusion from the Inter-trappean beds of Duddukuru, West Godavari District,
Andhra Pradesh, which have been assigned Early Palaeocene age (Khosla and Nagori, 2002). Presence of molt stages of the bulk
of non-marine and brackish water ostracods in the Inter-trappean beds of Jhilmili is suggestive that they were inhabitants
of low mesohaline inland pool/lake. The planktonic foraminifers were carried to this pool/lake by a marine transgression probably
from the east coast of India through the Trans Deccan Straits. 相似文献
14.
P. D. Sreedevi S. Owais H. H. Khan S. Ahmed 《Journal of the Geological Society of India》2009,73(4):543-552
An attempt has been made to study drainage morphometry and its influence on hydrology of Wailapalli watershed, South India.
For detailed study we used Shuttle Radar Topographic Mission (SRTM) data for preparing Digital Elevation Model (DEM), aspect
grid and slope maps, Geographical information system (GIS) was used in evaluation of linear, areal and relief aspects of morphometric
parameters. The study reveals that the elongated shape of the basin is mainly due to the guiding effect of thrusting and faulting.
The lower order streams are mostly dominating the basin. The development of stream segments in the basin area is more or less
affected by rainfall. The mean Rb of the entire basin is 3.89 which indicate that the drainage pattern is not much influenced
by geological structures. Relief ratio indicates that the discharge capability of these watersheds is very high and the groundwater
potential is meager. These studies are very useful for planning rainwater harvesting and watershed management. 相似文献
15.
D. K. Misra 《Journal of the Geological Society of India》2009,73(2):213-219
Geological mapping between Lohit and Dibang valleys of eastern Arunachal Pradesh reveals the existence of five thrust bound
tectonostratigraphic units. In ascending structural order from SW to NE these are: (1) Sewak Group, (2) Lalpani Group, (3)
Mayodiya Group, (4) Tidding Formation and (5) Lohit plutonic complex. This differs from previous mapping, because the three
tectonostratigraphic units (Sewak, Lalpani and Mayodiya) were grouped under a single unit, referred as the Mishmi crystallines.
The low-grade metamorphics of the Sewak Group occur at two different tectonic levels, one as persistent belt in the foothills
and the other in the tectonic window beneath the high-grade metamorphics of the Mayodiya thrust sheet in the Higher Himalaya.
The Tidding suture is the southeastern extension of the Indus-Tsangpo suture zone. 相似文献
16.
Shekhar Gupta P. S. Dandele M. B. Verma P. B. Maithani 《Journal of the Geological Society of India》2009,73(2):202-212
Groundwater in Palnad sub-basin is alkaline in nature and Na+-Cl−-HCO3− type around Macherla-Karempudi area in Guntur district, Andhra Pradesh. Total dissolved solids (TDS) show strong positive
correlation with Cl−, Na+, Ca2+ and Mg2+, and positive correlation with SO42−, K+ and HCO3−. Calcareous Narji Formation is the dominant aquifer lithology, and water-rock interaction controls the groundwater chemistry
of the area. Chloro-alkaline indices (CAI) are positive at Miriyala, Adigopula, Mutukuru, Macherla and Durgi suggesting replacement
of Na+ and K+ ions from water by Mg++ and Ca++ ions from country rock through base exchange reactions. Negative CAI values are recorded at Terala, Rayavaram and Nehrunagar,
which indicate exchange of Na+ and K+ from the rock as cation-anion exchange reaction (chloro-alkaline disequilibrium).
TDS range from 91 to 7100 ppm (Avg. 835 ppm) and exceed the prescribed limit of drinking water around Mutukuru, Durgi, Rayavaram,
Khambampadu and Ammanizamalmadaka areas. Scanty rainfall and insufficient groundwater recharge are the prime factors responsible
for high salinity in the area. Fluoride content ranges from <1 to 3.8 ppm and contaminated areas were identified around Macherla
(1 sq km; 3.8ppm), Mandadi (1 sq km, 2.1ppm) and Adigopula (2 sq km, <1 to 3.7 ppm). The % Na+ content varies from 17 to 85 with the mean value of 57, and eighty (80) samples showed higher %Na+ in comparison to the prescribed limit of 60 for irrigation water. Sodium Adsorption Ratio (SAR) and % Na+ in relation to total salt concentration indicate that groundwater (51%) mostly falls under doubtful to poor quality for irrigation
purpose. Groundwater of Adigopula village is fluoride contaminated and remedial measures are suggested to improve the water
quality. 相似文献
17.
Rajeev Menon P. V. Sunder Raju G. K. Reddy 《Journal of the Geological Society of India》2009,74(1):23-26
A geochemical soil sampling survey undertaken at Tumallpalle uranium mineralized zone Cuddapah district, has confirmed the
presence of uranium anomalies in soils. Bulk soil samples were collected at every 20 m along the traverse from approximately
30 cm below the surface and were assayed for uranium by x-ray fluorescence (XRF) and inductively coupled plasma mass spectrometry
(ICP-MS). The uranium anomalies detected by the insitu radiometric survey show a correlation with the helium highs. The soil
gas helium studies have aided in delineating the subsurface extension of the deposit. This study endeavors for an integration
of different techniques in a known area which could probably aid in delineating uranium zones for optimal exploitation in
the future exploration programmes. 相似文献
18.
Rashid Umar Izrar Ahmed Fakhre Alam Mohammad Muqtada Khan 《Environmental Geology》2009,58(6):1295-1300
The present study was undertaken to assess major ion chemistry of groundwater in parts of the Central Ganga Plain and observe
seasonal variations in its chemical quality. Systematic sampling was carried out during November 2005 and June 2006. The major
ion chemistry of groundwater shows large variations, so much so that at times the meteoric signature seems to be completely
obliterated. In many samples the concentrations of SO4, NO3 and F are above the permissible limit for human consumption. The graphical treatment of major ion chemistry helps in identifying
four types of groundwater. All possible ionic species such as NaCl, KCl, NaHCO3, NaSO4, KNO3, NaNO3, CaHCO3, MgHCO3, MgSO4 are likely to occur in groundwater system. The observed chemical variations may be attributed to sediment water interaction,
ion exchange, dissolution mechanisms and anthropogenic influences such as application of fertilizers and effluents from sugar
factories and paper mills. A general increase in TDS is observed in samples during June 2006. The increase in salinity is
attributed to evaporation from water table, irrigation return flows, anthropogenic activities and below average rainfall in
2005 and 2006.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
19.
Over-exploitation of groundwater results in decline of water levels, leading to intrusion of salt water along the coastal
region, which is a natural phenomenon. A groundwater quality survey has been carried out to assess such phenomena along the
coast of Visakhapatnam, Andhra Pradesh, India. Brackish groundwaters are observed in most of the wells. The rest of the wells
show a fresh water environment. The factors responsible for the brackish groundwater quality with respect to the influence
of seawater are assessed, using the standard ionic ratios, such as Ca2+:Mg2+, TA:TH and Cl−:HCO−
3. Results suggest that the brackish nature in most of the groundwaters is not due to the seawater influence, but is caused
by the hydrogeochemical process. Some influence of seawater on the groundwater quality is observed along the rock fractures.
The combined effect of seawater and urban wastewaters is due to the inferior quality of groundwater in a few wells, where
they are at topographic lows close to the coast. 相似文献
20.
Gabbros at Purimetla occur in close association with the alkaline pluton. Petrography and petrochemistry of these gabbros
indicate their tholeiitic nature. Chemical variation of these tholeiites suggests that an initial undersaturated tholeiitic
magma yielded oversaturated fractions in the final stages of differentiation. Their regional distribution suggests that basic
magmatism preceded the emplacement of the alkaline rocks in the Prakasam alkaline province. 相似文献