Matches in SemOpenAlex for { <https://semopenalex.org/work/W2085308719> ?p ?o ?g. }
Showing items 1 to 87 of
87
with 100 items per page.
- W2085308719 endingPage "169" @default.
- W2085308719 startingPage "169" @default.
- W2085308719 abstract "In the Oriola depression of Southern Portugal near the town of Evora, field examinations revealed the presence of Tertiary sedimentary deposits that had the consistency of duricrusts. These duricrusts, occurring close to the land surface, were examined in the field as well as in the laboratory, with the objective of establishing their composition and formation. Micromorphological examinations showed that the duricrusts were composed of clasts of fine sand to fine gravel sizes cemented together by a matrix dominated by either palygorskite or carbonate. The matrix : clasts ratio varied from about 1 : 3 when the cement was carbonate, to 3 : 1 or higher when the matrix was palygorskite. Occasionally the ratio in the latter was even higher. The clasts consisted of quartz, feldspar, and some Mg-rich metamorphic minerals. The palygorskite matrix fibres were arranged in mats within which they had parallel orientation. The mats or ‘domains’, which had a length of 15–25 □m and a width of about 40 □m, showed random orientation. In analogy to the term ‘calcrete’ the term ‘palycrete’ is used for the palygorskite duricrusts. The palycrete, of an average thickness of 0.5 m, frequently rested directly on the Hercynian basement rocks, and was covered by a recent solum. In the B horizons of the solum, the palygorskite appeared to undergo recent weathering and transformation into smectite. The duricrusts were proposed to have formed by authigenic calcite or palygorskite, which filled the interstices between clastic particles that had been deposited on Hercynian basement rocks following their peneplanation in the early Tertiary. The proposed environment of deposition and formation was that of an intermittent playa-lake in a semi-arid, seasonal climate, where strong evaporative processes had been active. Alteration and weathering of the mafic minerals contained in some of the clasts, in addition to interstitial solutions rich in Si and Mg, had created the chemical environment required for palygorskite neoformation. From the state of weathering–disintegration of the palygorskite in the soils formed on the palycrete, it is inferred that the environment for palygorskite neoformation had ceased to exist after palycrete formation." @default.
- W2085308719 created "2016-06-24" @default.
- W2085308719 creator A5003057272 @default.
- W2085308719 creator A5016455614 @default.
- W2085308719 creator A5047723750 @default.
- W2085308719 creator A5079255442 @default.
- W2085308719 creator A5084048949 @default.
- W2085308719 creator A5086237924 @default.
- W2085308719 date "2000-01-01" @default.
- W2085308719 modified "2023-09-25" @default.
- W2085308719 title "Palygorskite-cemented crusts (palycretes) in Southern Portugal" @default.
- W2085308719 doi "https://doi.org/10.1071/sr99002" @default.
- W2085308719 hasPublicationYear "2000" @default.
- W2085308719 type Work @default.
- W2085308719 sameAs 2085308719 @default.
- W2085308719 citedByCount "29" @default.
- W2085308719 countsByYear W20853087192012 @default.
- W2085308719 countsByYear W20853087192013 @default.
- W2085308719 countsByYear W20853087192015 @default.
- W2085308719 countsByYear W20853087192018 @default.
- W2085308719 countsByYear W20853087192019 @default.
- W2085308719 countsByYear W20853087192020 @default.
- W2085308719 countsByYear W20853087192021 @default.
- W2085308719 crossrefType "journal-article" @default.
- W2085308719 hasAuthorship W2085308719A5003057272 @default.
- W2085308719 hasAuthorship W2085308719A5016455614 @default.
- W2085308719 hasAuthorship W2085308719A5047723750 @default.
- W2085308719 hasAuthorship W2085308719A5079255442 @default.
- W2085308719 hasAuthorship W2085308719A5084048949 @default.
- W2085308719 hasAuthorship W2085308719A5086237924 @default.
- W2085308719 hasConcept C115393850 @default.
- W2085308719 hasConcept C127313418 @default.
- W2085308719 hasConcept C130452526 @default.
- W2085308719 hasConcept C138170599 @default.
- W2085308719 hasConcept C151730666 @default.
- W2085308719 hasConcept C17409809 @default.
- W2085308719 hasConcept C178790620 @default.
- W2085308719 hasConcept C185592680 @default.
- W2085308719 hasConcept C199289684 @default.
- W2085308719 hasConcept C26687426 @default.
- W2085308719 hasConcept C2779870107 @default.
- W2085308719 hasConcept C2780191791 @default.
- W2085308719 hasConcept C2780659211 @default.
- W2085308719 hasConcept C2780873218 @default.
- W2085308719 hasConcept C40212044 @default.
- W2085308719 hasConcept C40724407 @default.
- W2085308719 hasConcept C41440632 @default.
- W2085308719 hasConcept C6494504 @default.
- W2085308719 hasConceptScore W2085308719C115393850 @default.
- W2085308719 hasConceptScore W2085308719C127313418 @default.
- W2085308719 hasConceptScore W2085308719C130452526 @default.
- W2085308719 hasConceptScore W2085308719C138170599 @default.
- W2085308719 hasConceptScore W2085308719C151730666 @default.
- W2085308719 hasConceptScore W2085308719C17409809 @default.
- W2085308719 hasConceptScore W2085308719C178790620 @default.
- W2085308719 hasConceptScore W2085308719C185592680 @default.
- W2085308719 hasConceptScore W2085308719C199289684 @default.
- W2085308719 hasConceptScore W2085308719C26687426 @default.
- W2085308719 hasConceptScore W2085308719C2779870107 @default.
- W2085308719 hasConceptScore W2085308719C2780191791 @default.
- W2085308719 hasConceptScore W2085308719C2780659211 @default.
- W2085308719 hasConceptScore W2085308719C2780873218 @default.
- W2085308719 hasConceptScore W2085308719C40212044 @default.
- W2085308719 hasConceptScore W2085308719C40724407 @default.
- W2085308719 hasConceptScore W2085308719C41440632 @default.
- W2085308719 hasConceptScore W2085308719C6494504 @default.
- W2085308719 hasIssue "1" @default.
- W2085308719 hasLocation W20853087191 @default.
- W2085308719 hasOpenAccess W2085308719 @default.
- W2085308719 hasPrimaryLocation W20853087191 @default.
- W2085308719 hasRelatedWork W1561573454 @default.
- W2085308719 hasRelatedWork W2019290308 @default.
- W2085308719 hasRelatedWork W2034495380 @default.
- W2085308719 hasRelatedWork W2106776983 @default.
- W2085308719 hasRelatedWork W2283690737 @default.
- W2085308719 hasRelatedWork W3151656700 @default.
- W2085308719 hasRelatedWork W3159055879 @default.
- W2085308719 hasRelatedWork W3206352347 @default.
- W2085308719 hasRelatedWork W833032684 @default.
- W2085308719 hasRelatedWork W2692878541 @default.
- W2085308719 hasVolume "38" @default.
- W2085308719 isParatext "false" @default.
- W2085308719 isRetracted "false" @default.
- W2085308719 magId "2085308719" @default.
- W2085308719 workType "article" @default.