Mineralogical and geochemical characteristics (major, minor, trace elements and <i>REE</i>) of detrital and authigenic clay minerals in a Cenozoic sequence from Ross Sea, Antarctica

Setti, Massimo; Marinoni, Luigi; López-Galindo, Alberto

doi:10.1180/000985503540143

Cited by 52 publications

(37 citation statements)

References 18 publications

(31 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Furthermore, there is no textural or mineralogical evidence of hydrothermal activity. Hydrothermal saponite forms coatings on other mineral grains, inside veins and replaces mafic minerals (18,25). It may be accompanied of other secondary Fe and Mg-rich minerals including celadonite, talc, nontronite and metal oxide/sulfides (12).…”

Section: Mineralogy Of Basin Sections and Member 4 In The Yangtze Gormentioning

confidence: 99%

Mineralogical constraints on the paleoenvironments of the Ediacaran Doushantuo Formation

Bristow

Kennedy

Derkowski

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

108

View full text Add to dashboard Cite

Assemblages of clay minerals are routinely used as proxies for paleoclimatic change and paleoenvironmental conditions in Phanerozoic rocks. However, this tool is rarely applied in older sedimentary units. In this paper, the clay mineralogy of the Doushantuo Formation in South China is documented, providing constraints on depositional conditions of the Ediacaran Yangtze platform that host the earliest animal fossils in the geological record. In multiple sections from the Yangtze Gorges area, trioctahedral smectite (saponite) and its diagenetic products (mixed-layer chlorite/smectite, corrensite, and chlorite) are the dominant clays through the lower 80 m of the formation and constitute up to 30 wt% of the bulk rock. Saponite is interpreted as an in situ early diagenetic phase that formed in alkaline conditions (pH > 9). The absence of saponite in stratigraphically equivalent basin sections, 200 -400 km to the south, indicates that alkaline conditions were localized in a nonmarine basin near the Yangtze Gorges region. This interpretation is consistent with crustal abundances of redox-sensitive trace elements in saponitic mudstones deposited under anoxic conditions, as well as a 10‰ difference in the carbon isotope record between Yangtze Gorges and basin sections. Our findings suggest that nonmarine environments may have been hospitable for the fauna preserved in the Yangtze Gorges, which includes the oldest examples of animal embryo fossils and acanthomorphic acritarchs.clays ͉ saponite ͉ Neoproterozoic ͉ nonmarine ͉ early animals

show abstract

Section: Mineralogy Of Basin Sections and Member 4 In The Yangtze Gormentioning

confidence: 99%

Mineralogical constraints on the paleoenvironments of the Ediacaran Doushantuo Formation

Bristow

Kennedy

Derkowski

et al. 2009

Proc. Natl. Acad. Sci. U.S.A.

108

View full text Add to dashboard Cite

show abstract

“…A distribuição dos elementos maiores é controlada principalmente pelo teor relativo de minerais na fração argila dos solos: teores elevados de SiO 2 , Al 2 O 3 e K 2 O geralmente estão relacionados com clorita e ilita em abundância, pois o Si, Al e K são mais facilmente retidos na estrutura desses minerais (Setti et al, 2004). Em particular, a ilita é importante carreador de K 2 O em sedimentos (Wedepohl, 1978); entretanto, Fe 2 O 3 e MgO estão relacionados a solos ricos em esmectita autigênica (Setti et al, 2004).…”

Section: Geoquímica Dos Elementos Maioresunclassified

“…Em particular, a ilita é importante carreador de K 2 O em sedimentos (Wedepohl, 1978); entretanto, Fe 2 O 3 e MgO estão relacionados a solos ricos em esmectita autigênica (Setti et al, 2004). Todos os solos da RPPN possuem caulinita, mica (ilita), traços de esmectita e VHE na fração argila.…”

Section: Geoquímica Dos Elementos Maioresunclassified

Geoquímica de solos do pantanal norte, Mato Grosso

Coringa

Couto

Vidal‐Torrado

2014

Rev. Bras. Ciênc. Solo

View full text Add to dashboard Cite

Torrado (4) RESUMOA caracterização e análise geoquímica de solos permitem compreender os processos de migração, dispersão e concentração de elementos químicos no perfil, embasando a correlação dos atributos deles com as classes de solos formadas, o que possibilita inferências acerca das gêneses desses solos. Esta pesquisa teve por objetivos caracterizar e interpretar a composição geoquímica total de elementos maiores e menores em classes de solos representativas do Pantanal norte, na sub-região de Barão de Melgaço, Mato Grosso, Brasil. Foram selecionados 20 perfis das principais classes de solos do Pantanal e analisadas amostras dos horizontes A e B (ou C) quanto à concentração de óxidos totais por espectrometria de fluorescência de raios-X, além das caracterizações física, química e mineralógica. Os solos subdividiram-se em dois tipos geoquímicos: um composto por textura arenosa a franco-arenosa com teores relativamente elevados de SiO 2 e predominância de caulinita e quartzo, com menor teor de bases e elementos-traço; e outro composto por textura mais argilosa, geoquimicamente heterogêneos e com teores significativos de minerais 2:1, Al 2 O 3 , óxidos de Fe e Mn, bases e elementos-traço.Termos de indexação: óxidos totais, solos hidromórficos, elementos-traço.

show abstract

“…7b, e.g. Setti et al, 2004). However, whilst modern day weathering processes can induce large variations in 87 Sr / 86 Sr primarily as a result of large inter-mineral variations in the Rb / Sr ratio (e.g.…”

Section: Preferential Leaching Of a Labile Phasementioning

confidence: 99%

Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard)

et al. 2018

View full text Add to dashboard Cite

Abstract. The identification of sediment sources to the ocean is a prerequisite to using marine sediment cores to extract information on past climate and ocean circulation. Sr and Nd isotopes are classical tools with which to trace source provenance. Despite considerable interest in the Arctic Ocean, the circum-Arctic source regions are poorly characterised in terms of their Sr and Nd isotopic compositions. In this study we present Sr and Nd isotope data from the Paleogene Central Basin sediments of Svalbard, including the first published data of stream suspended sediments from Svalbard.The stream suspended sediments exhibit considerable isotopic variation (εNd = −20.6 to −13.4; 87 Sr / 86 Sr = 0.73421 to 0.74704) which can be related to the depositional history of the sedimentary formations from which they are derived. In combination with analysis of the clay mineralogy of catchment rocks and sediments, we suggest that the Central Basin sedimentary rocks were derived from two sources. One source is Proterozoic sediments derived from Greenlandic basement rocks which are rich in illite and have high 87 Sr / 86 Sr and low εNd values. The second source is Carboniferous to Jurassic sediments derived from Siberian basalts which are rich in smectite and have low 87 Sr / 86 Sr and high εNd values. Due to a change in depositional conditions throughout the Paleogene (from deep sea to continental) the relative proportions of these two sources vary in the Central Basin formations. The modern stream suspended sediment isotopic composition is then controlled by modern processes, in particular glaciation, which determines the present-day exposure of the formations and therefore the relative contribution of each formation to the stream suspended sediment load. This study demonstrates that the Nd isotopic composition of stream suspended sediments exhibits seasonal variation, which likely mirrors longer-term hydrological changes, with implications for source provenance studies based on fixed endmembers through time.

show abstract

Mineralogical and geochemical characteristics (major, minor, trace elements and REE) of detrital and authigenic clay minerals in a Cenozoic sequence from Ross Sea, Antarctica

Cited by 52 publications

References 18 publications

Mineralogical constraints on the paleoenvironments of the Ediacaran Doushantuo Formation

Mineralogical constraints on the paleoenvironments of the Ediacaran Doushantuo Formation

Geoquímica de solos do pantanal norte, Mato Grosso

Clay mineralogy, strontium and neodymium isotope ratios in the sediments of two High Arctic catchments (Svalbard)

Contact Info

Product

Resources

About