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矿业科学技术学报：英文版 2013年第3期23卷 457-462页

作者： anju pandey Ministry of Earth Sciences Prithvi Bhavan New Delhi 110003 India

Polymetallic sulphides have been consistent source of metals like iron, copper, zinc and lead. Apart from these they are also seen as economically viable resources of silver and gold. As the demand of these metals is showing an astoundingly increasing trend, the search for their resources has also increased in similar folds. This has resulted in many nations' focus on deep seabed resources of the polymetallic sulphides. Consequently, International Seabed Authority (ISBA) has provided 'Regulations' to obtain plan of work for exploration of polymetallic sulphide deposits in deep seabed 'Area'. Following the release of these Regulations, several countries are in the process of obtaining the licence for exploration of these metals from the deep seabed regions. Detailed information about the science and ISBA Regulations for exploration of polymetallic sulphide deposits is prerequisite to submit an application to ISBA for their exploration. The current contribution provides a comprehensive review of the science behind locating polymetallic sulphide deposits in geological setting of deep seabed as well as about the ISBA Regulations for their exploration.

关键词： Polymetallic sulphide International Seabed Authority Exploration Mid ocean ridges

Variability of the Southwest Monsoon since the Last 25 000 Years and Their Possible Causes: Role of Northern Hemisphere versus Tibetan Plateau

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Journal of Earth Science 2013年第3期24卷 428-436页

作者： anju pandey Ravi Mishra Centre for Climate Change Research National Centre for Antarctic & Ocean Research

High-precision, clay sediment oxygen and hydrogen isotopes analyses of Pleistocene-Holocene deep-sea sediments from the Bay of Bengal （BOB） are presented for the first time. Our study shows that the major source of sediments in the study area, since the last-25 000 years, is likely to be the Higher Himalayan crystalline rocks. Further, the study of these stable isotope data displays the variation of southwest monsoon （SWM） in the BOB region since the last-25 000 years and the cause behind the variation has been interpreted. The δ 18 O values of the clay sediments are compared with δ 18 O values of the BOB seawater. This comparison shows that the clay sediment δ 18 O values of the studied sediment cores temporally vary along with the changes in strength of the SWM. Based on the changes in the clay sediment δ 18 O values of the studied sediment, we evaluate the variance in the SWM since the last 25 000 years in the BOB. Our results are consistent with previous work in the region based on other proxies. To evaluate the factors influencing the intensity of the SWM since the last glacial maxima, we conducted comparative analyses of the studied clay sediment δ 18 O values with δ 18 O values in the Greenland ice cores （GISP2） and Tibetan ice cores （Guliya）. The results from this comparative study show that large-scale changes in the intensity of the SWM since 25 000 years are affected by the climate oscillations of the Northern Hemisphere, but rapid and abrupt fluctuations in the SWM seem to be controlled by the amount of snow cover in the Tibetan Plateau.

关键词： southwest monsoon Bay of Bengal Tibetan Plateau clay stable isotope.

Seismic stratigraphy and the sedimentation history in the Laxmi Basin of the eastern Arabian Sea:Constraints from IODP Expedition 355

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Geoscience Frontiers 2021年第3期12卷 489-502页

作者： Nisha Nair Dhananjai K.pandey anju pandey R.Prerna National Centre for Polar and Ocean Research(NCPOR) Ministry of Earth SciencesVasco-da-GamaGoa 403804India H-V3-NCPOR Campus Vasco-da-GamaGoa 403804India

Detailed interpretation of seismic stratigraphic sequences in the Laxmi Basin of the eastern Arabian Sea are presented in this study using closely spaced high resolution multi-channel seismic(MCS)data.Our stratigraphic interpretation is further corroborated using recent drilling results in the Laxmi Basin,derived from the long sediment cores collected during International Ocean Discovery Program(IODP)Expedition 355.Integrated core-log interpretation discussed in the present study,offer important insights about the lithostratigraphic variations in this region.Analyses of multi-channel seismic reflection data reveal five depositional sequences(ranging from Paleocene to Recent)that led to the development of this marginal basin since the Cenozoic period.Regional igneous basement is successfully imaged,which was also validated by deep sea coring during the IODP Expedition 355.In the present study,we primarily focus on the post-rift sedimentation in the Laxmi Basin and its possible mechanisms.Our detailed interpretation in the prevailing tectonic framework of the basin suggests that near-shelf oldest volcaniclastic sedimentation immediately overlying the acoustic basement is linked to the onset of India-Madagascar and India-Seychelles rifting activities during the Late Cretaceous period.Eventually,during the Early-Mid to Late Miocene,the basin received maximum sedimentation dominantly through an extensive mass transport mechanism implying possible large-scale deformation on the Indian shelf.Subsequent sediment input to the basin appears to have been fed variably via the Indus Fan as well as coastal discharge from the Indian mainland.The total sediment thickness in the Laxmi Basin ranges from 1.1 to 3.5 km.New stratigraphic information and sediment isopach maps presented here provide vital information about syn-and post-rift sedimentation pattern in the region and their long term tectonic implications.

关键词： Seismic stratigraphy Laxmi Basin Arabian Sea Site U1456 Site U1457 IODP Expedition 355

Late Cenozoic seismic stratigraphy of the Andaman Forearc Basin,Indian Ocean

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Petroleum Science 2017年第4期14卷 648-661页

作者： Dhananjai K.pandey Goli Anitha Ramesh Prerna anju pandey ESSO-National Centre for Antarctic and Ocean Research Headland SadaVasco da GamaGoa 403 804India

Interpretation of new multichannel seismic reflection data from the Andaman Forearc Basin(AFB) in the northern Indian Ocean is presented here. The highquality multichannel seismic data from the Andaman Forearc region enable us to examine the seismic characters and to demarcate seismic sequences bounded by distinct unconformities. Ages of marked seismic horizons have been calibrated with available litholog data from nearby industry boreholes. Seismic interpretation of new data shows that the AFB is filled with * 4.5-s-two way travel time(TWT) thick Neogene to Recent sediments. The entire basin assemblage exhibits two distinct major sequences pertaining to the Neogene and Quaternary times. A large part of the basin is filled with intermittent mass transport deposits(MTD). We infer that the episodic uplift of the Invisible Bank, protuberance of the outerarc and regular deformation through reactivation of preexisting normal faults since the Pleistocene could be attributed as causal mechanisms for the MTDs. Strong bottom simulating reflectors are identified in the Late Miocene and younger sediments of the outerarc and AFB at a depth of * 0.6 s TWT and correspond to the presence of gas hydrates in this region. Our interpretations have significant implications for geodynamic as well as resource exploration in the AFB.

关键词： Andaman Forearc Basin Neogene Uplift Invisible Bank Outerarc Stratigraphy

Basement tectonics and flexural subsidence along western continental margin of India

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Geoscience Frontiers 2017年第5期8卷 1009-1024页

作者： D.K.pandey Nisha Nair anju pandey G. Sriram ESSO-National Centre for Antarctic and Ocean Research Goa India

The Paleocene-recent post-rift subsidence history recorded in the Mumbai Offshore Basin off western continental margin of India is examined. Results obtained through 2-D flexural backstripping modelling of new seismic data reveal considerable thermo-tectonic subsidence over last ca. 56 Myr. Reverse postrift subsidence modelling with variable β stretching factor predicts residual topography of ca. 2000 m to the west of Shelf Margin Basin and fails to restore late Paleocene horizon and the underlying igneous basement to the sea level. This potentially implies that:(1) either the igneous basement formed during the late Cretaceous was emplaced under open marine environs; or(2) a laterally varying cumulative subsidence occurred within Mumbai Offshore Basin(MOB) during ca. 68 to ca. 56 Ma. Pre-depositional topographic variations at ca. 56 Ma across the basin could be attributed to the extensional processes such as varied lower crustal underplating along Western Continental Margin of India(WCMI). Investigations about basement tectonics after unroofing of sediments since late Paleocene from this region support a transitional and heavily stretched nature of crust with high to very high β factors. Computations of past sediment accumulation rates show that the basin sedimentation peaked during late Miocene concurrently with uplift of Himalayan-Tibetan Plateau and intensification of Indian monsoon system. Results from basin subsidence modelling presented here may have significant implications for further studies attempting to explore tectono-climatic interactions in Asia.

关键词： Continental rifting Subsidence Mumbai Offshore Basin Backstripping Arabian Sea Laxmi Basin

Petrogenesis of massif-type anorthosite complex, Gruber, Central Dronning Maud Land, East Antarctica: Implications for magma source and evolution

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Chinese Journal Of Geochemistry 2009年第4期28卷 340-350页

作者： anju pandey Amit Dharwadkar Rasik Ravindra Andy Milton National Oceanography Centre European WaySouthampton SO14 3ZH United Kingdom Geological Survey of India FaridabadNH31 Haryana India National Centre for Antarctic & Ocean Research Goa-403804 India

The origin of anorthosite and associated igneous gabbronorite and ferrodiorite was investigated through detailed study of a typical massif-type anorthosite complex from Gruber, Central Dronning Maud Land, East Antarc- tica. Field observations showed that the Gruber Complex is made up of gabbronorite-anorthosite pluton which was intruded by ferrodiorite dykes. Systematic samples collected from the Gruber Complex revealed significant geo- chemical variations within the region. Four rock types have been identified, based on modal proportions of mineral phases and their geochemistry data. Clinopyroxene-gabbronorite and plagioclase-gabbronorite are the two types of gabbronorite with the dominance of clinopyroxene and plagioclase, respectively. Anorthosite is represented by rocks having predominance of plagioclase with minor clinopyroxene. Ferrodiorite is characterized by modal abundance of orthopyroxene and Fe-Ti oxide. Major and trace element systematics showed that all the four rock types are co-magmatic and are related through fractional crystallization. Based on this study, it is reported that clinopyroxene was the first phase to crystallize followed by plagioclase and then Fe-Ti oxides. Furthermore, trace element composition of the parental melt was calculated using LA-ICPMS analysis of the most primitive, pure clinopyroxene found in the clinopyroxene gabbronorite. Our analyses suggested that the parental melt was similar to that of continental arc basalt and showed signatures of subduction-related metasomatism. Based on mineral chemical and geochemical data, it is interpreted that the parent melt went through changing sequence of crystallization which led to the forma- tion of massive anorthosite.

关键词：东南极洲斜长岩岩浆源块型成因中央演变

Mechanism of crustal extension in the Laxmi Basin,Arabian Sea

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Geodesy and Geodynamics 2015年第6期6卷 409-422页

作者： pandey anju pandey Dhananjai K ESSO-National Centre for Antarctic and Ocean Research Ministry of Earth Sciences

Continental rifting and magmatism has been extensively studied worldwide as it is believed that continental rifting, break up of continents and associated magmatism lead to genesis of new oceanic crust. However, various regions of the world show that these processes may lead to genesis of other types of crust than the oceanic crust. Laxmi Basin in the western continental margin of the India is one such region with an enigmatic crust.Due to its extreme strategic significance for the palaeogeographic reconstruction of continents during Cretaceous continental breakup of India, this basin has attracted various workers for more than two decades. However, still the issue of nature of crust in the basin remains controversial. In this contribution, in order to identify nature of crust, mechanism of continental extension in the Laxmi Basin has been studied for the first time through newly acquired seismic data from the basin. Here, we propose a plausible mechanism of crustal extension in the Laxmi Basin which eventually constrains the nature of crust of the Laxmi Basin. We have demonstrated that the crust in the Laxmi Basin can be categorised in two zones of stretched and transitional crust. In the stretched zone several fault bounded horst and graben structures are identified which preserve syn- and post-rift sediments along with different periods of hiatus in sedimentations as unconformities. These faults are identified as listric faults in the upper crust which sole out in the detachment faults.Detachment faults decouples the upper brittle and lower ductile crust. The transitional crust is identified as heavily intruded by sills and basaltic volcanic which were emplaced due to melting of subcontinental mantle（SCM） after hyper-stretching of crust and serpentinisation of the SCM. Panikkar Ridge is proposed to be one such basaltic volcanic body derived from melting of lower part of the SCM.

关键词： Laxmi Basin Panikkar Ridge Continental extension Mantle exhumation Detachment surface

Multi-wavelength nanowire micro-LEDs for future high speed optical communication

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Opto-Electronic Advances 2024年第3期7卷 1-3页

作者： Ayush pandey Zetian Mi Department of Electrical Engineering and Computer Science University of MichiganAnn ArborMI 48109USA

The future of optoelectronics is directed towards small-area light sources,foremost being microLEDs.However,their use has been inhibited so far primarily due to fabrication and integration challenges,which impair efficiency and yield.Recently,bottom-up nanostructures grown using selective area epitaxy have garnered attention as a solution to the aforementioned issues.Prof.Lan Fu et.***.have used this technique to demonstrate uniform p-i-n core-shell InGaAs/InP nanowire array light emitting diodes.The devices are capable of voltage and geometry-controlled multi-wavelength and high-speed operations.Their publication accentuates the wide capabilities of bottom-up nanostructures to resolve the difficulties of nanoscale optoelectronics.

关键词： communication high operations

Prediabetes in children and adolescents:A ticking bomb!

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World Journal of Clinical Pediatrics 2024年第2期13卷 11-15页

作者： anju Gupta Nitin Choudhary Nishkarsh Gupta Department of Anesthesiology Pain Medicine and Critical CareAll India Institute of Medical ScienceNew Delhi 110076India Department of Onco-Anesthesiology and Palliative Medicine All India Institute of Medical ScienceNew Delhi 110029India

Prediabetes in children and adolescents is on the rise which has drawn significant attention over the past decade.It is an early warning sign of the underlying pathophysiological changes which in due course of time might compound into type II diabetes mellitus.The incidence of prediabetes in adolescents ranges from 4%-23%which is alarmingly high and requires active intervention from the system.We have discussed early identification of high-risk patients,prompt screening and active intervention to manage this growing problem.

关键词： Prediabetes Children Adolescents Glucose metabolism Complications

Function and dysfunction of GEMIN5:understanding a novel neurodevelopmental disorder

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Neural Regeneration Research 2024年第11期19卷 2377-2386页

作者： Charles H.Nelson Udai B.pandey Department of Pediatrics Division of Child NeurologyChildren’s Hospital of PittsburghUniversity of Pittsburgh Medical CenterPittsburghPAUSA Children’s Neuroscience Institute Children’s Hospital of PittsburghUniversity of Pittsburgh Medical CenterPittsburghPAUSA

The recent identification of a neurodevelopmental disorder with cerebellar atrophy and motor dysfunction(NEDCAM)has resulted in an increased interest in GEMIN5,a multifunction RNA-binding protein.As the largest member of the survival motor neuron complex,GEMIN5 plays a key role in the biogenesis of small nuclear ribonucleoproteins while also exhibiting translational regulatory functions as an independent protein.Although many questions remain regarding both the pathogenesis and pathophysiology of this new disorder,considerable progress has been made in the brief time since its discovery.In this review,we examine GEMIN5 within the context of NEDCAM,focusing on the structure,function,and expression of the protein specifically in regard to the disorder itself.Additionally,we explore the current animal models of NEDCAM,as well as potential molecular pathways for treatment and future directions of study.This review provides a comprehensive overview of recent advances in our understanding of this unique member of the survival motor neuron complex.

关键词： cerebellar atrophy GEMIN5 neurodevelopmental disorder neurological disease SMN complex