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121.
Sanjay Kumar Goyal B. S. Chaudhary Omvir Singh G. K. Sethi Praveen K. Thakur 《Environmental Earth Sciences》2010,61(8):1587-1597
Groundwater is a major resource for meeting huge domestic and agricultural requirements of Kaithal district in Haryana. Therefore, evaluation of its quality in terms of suitability for domestic and agricultural sectors is necessary for sustainable management of the resource. The present study has analyzed pre- and post-monsoon physico-chemical data of groundwater samples from bore wells spread over the entire district. Spatial distribution maps were generated for hydrogen ion concentration, total dissolved solids, total hardness, electrical conductivity, sodium adsorption ratio, residual sodium carbonate and percent sodium using the geographic information system. Furthermore, the study area was demarcated into different groundwater quality zones for domestic and agricultural use by applying various national and international standards. It was observed from the study that the groundwater was predominantly hard, alkaline and saline in nature. However, it was within safe limits for domestic use. Further, it was also experienced from the analysis that in about two-third parts of the district, groundwater was in desirable-to-permissible quality class for agricultural use but hazardous for soil as well as for crops in the remaining part. Also, a moderation in water quality was observed after the monsoon season, which can be attributed to a possible dilution due to groundwater recharge. 相似文献
122.
New geochemical data of the crater-facies Tokapal kimberlite system sandwiched between the lower and upper stratigraphic horizons of the Mesoproterozoic lndravati Basin a::e presented. The kimberlite has been subjected to extensive and pervasive low-temperature alteration. Spinel is the only primary phase identifiable, while olivine macrocrysts and juvenile lapilli are largely pseudomorphed (talc-serpentine- carbonate alteration). However, with the exception of the alkalies, major element oxides display systematic fractionation trends; likewise, HFSE patterns are well correlated and allow petrogenetic interpretation. Various crustal contamination indices such as (SiO2 + AI::O3 ~ Na20)](MgO ~ K20) and Si] Mg are close to those of uncontaminated kimberlites. Similar La]Yb ('79-109) of the Tokapal samples with those from the kimberlites of Wajrakarur (73-145) and Narayanpet (72-156), Eastern Dharwar craton, southern India implies a similarity in their genesis. In the discriminant plots involving HFSE the Tokapal samples display strong affinities to Group 1I kimberlites from southern Africa and central India as well as to 'transitional kimberlites' from the Eastern Dharwar craton, southern India, and those from the Prieska and Kuruman provinces of southern Africa. There is a striking ~;imilarity in the depleted-mantle (TOM) Nd model ages of the Tokapal kimberlite system, Bastar craton, th~ kimberlites from NKF and WKE Eastern Dharwar craton, and the Majhgawan diatreme, Bundelkhand craton, with the emplacement age of some of the lamproites from within and around the Palaeo~Mesoproterozoic Cuddapah basin, southern India. These similar ages imply a major tectonomagmatic event, possibly related to the break- up of the supercontinent of Columbia, at 1.3-1.5 Ga across the l:hree cratons. The 'transitional' geochemical features displayed by many of the Mesoproterozoic po~:assic-ultrapotassic rocks, across these Indian cratons are inferred to be memories of the metasomatisi 相似文献