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Interpreta??es paleoambientais obtidas a partir das varia??es na colora??o das carapa?as de foraminíferos, da Enseada do Flamengo, SPDOI: 10.1590/S0373-55241994000100005 Keywords: foraminifers, carapaces impregnated with limonite, carapaces filled with pyrite, potencial redox, cores, holocene, reducing environment, enseada do flamengo: sp, brasil. Abstract: two cores obtained respectively from saco da ribeira and saco do perequê-mirim, both located within flamengo bay, northern coast of s?o paulo, brazil, have been studied. at former site many pyrite- filled foraminifera carapaces were observed. at the other site, there occur carapaces filled with pyrite, as well as carapaces impregnated with limonite and iron monosulfide, the latter showing a close relationship between limonite and iron monosulfide impregnated carapaces with strongly bioturbated levels. these observations reveal more reducing conditions in the saco da ribeira than in the saco do perequê-mirim. by quantifying the number of carapaces impregnated with hydroxide/oxide vs. those filled by ferrous sulfide, it was possible to estimate some differences in redox potenciais at these two sites.
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