K VIJAYA KUMAR
Articles written in Journal of Earth System Science
Volume 95 Issue 1 March 1986 pp 103-115
Radioelement geochemistry of alkali granites of the Kerala region, south-west India
Th, U and K abundances in four alkali granites of the Kerala region, south-west India, are presented. The plutons show high radioelement levels, correlatable with those of alkali granites in other regions. The nature of variation is consistent with the correlation of Th and U with accessory phases like sphene, zircon, allanite, apatite and monazite. A geochronologic correlation is also observed between the alkali granites and the Th-bearing beach placers of the region. The petrogenetic features of the alkali plutons, their taphrogenic association, Pan-African affiliation and high Th/U levels suggest that the alkali plutons are favourable locales for radioelement exploration.
Volume 130 All articles Published: 5 February 2021 Article ID 0021 Research article
K V NARASIMHA MURTHY R SARAVANA G KISHORE KUMAR K VIJAYA KUMAR
Surface air temperature (SAT) is a key meteorological parameter. Modelling and forecasting of the SAT has vital importance to understand the ecological and agricultural changes. We utilized all India monthly mean SAT, which covers a time span of 1951–2016. We used structural time series (STS) analysis to model and forecast the monthly mean SAT. Forecast during 2006–2016 well matched with the observational data. Further, the forecast of monthly mean surface air temperature patterns for 2017–2019 shows a good agreement with climatological behaviour. Note that we observed an increasing trend 0.0009$^{\circ}$C per year in monthly mean surface air. Further, we noticed slight chance of rise in temperature about 0.1$^{\circ}$C specially for the months of April, May and December in the years 2017–2019.
$\bf{Highlights}$
$\bullet$ An increasing trend of 0.0009$^{\circ}$C per year is evident in the monthly mean surface air.
$\bullet$ Raise in temperature of 0.1$^{\circ}$C is evident during April, May and December.
Volume 131 All articles Published: 24 August 2022 Article ID 0186 Letter
MORE B LAXMAN B NAGARAJU K NAGARAJU K VIJAYA KUMAR
In the present study, we have demarcated five zones within the Deccan Volcanic Province (DVP):
(1) Kutch, (2) Western Ghats, (3) Central Son–Narmada, (4) Eastern Son–Narmada and (5) South- Eastern Deccan
(SE DVP) to evaluate spatial geochemical variations within the DVP possibly controlled
by different eruption loci. True OIB-type unmixed trace element and isotopic signatures are demon strated
by both alkali and tholeiitic basalts from Kutch and a small proportion from Western Ghats.
However, large number of tholeiitic basaltic samples from both the zones and Central Son–Narmada zone
illustrate sub-continental lithosphere mantle (SCLM) signatures. The Eastern Son–Narmada and SE
DVP zones of the DVP show evolved compositions, but are dominantly derived from sub-lithospheric
sources. The plume–lithosphere interaction is represented by mixing and/or assimilation and fractional
crystallisation (AFC) of plume-derived melts with the sub-continental lithospheric mantle (SCLM)-
derived melts, sediments preserved in the SCLM, lower crustal (TTG-type) and upper crustal (granitic)
components. We argue that melts from the Archaean sediments preserved in the SCLM,
$\bf{Highlights}$
$\bullet$ The melts generated from the Archaean sediments preserved in the SCLM, represented by calc-alkaline lamprophyres, are most likely the components that interacted with the plume-derived as well as SCLM-derived partial melts during the formation of DVP.
$\bullet$ Mixing and/or AFC of calc-alkaline lamprophyres, TTGs and granites by plume-derived melts and SCLM peridotite-derived melts explain total geochemical spread of the Deccan basalts.
$\bullet$ Approximately, 10% mixing and/or ~20% AFC of Archean calc-alkaline lamprophyre melts can make original sub-lithosphere melts display apparent SCLM signatures.
$\bullet$ The basalts from the western side of DVP have undergone higher levels of assimilation compared to those from the eastern side.
Volume 132, 2023
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