| 释义 |
Definition of calcrete in English: calcretenoun ˈkalkriːt mass nounGeology A breccia or conglomerate cemented together by calcareous material, formed in soils in semi-arid conditions. Also called caliche Example sentencesExamples - The stacked and generally well-developed nature of the calcrete profiles, by comparison with Quaternary calcretes indicate that the more and phases persisted for hundreds of thousands of years.
- In more arid areas calcrete (consisting of calcium carbonate) is the duricrust.
- The Yellow Cat Member contains a basal calcrete with interbedded sands and clays and extends upward to a prominent sandstone unit.
- The region's Mediterranean style climate and annual water deficit has led to extensive calcrete development.
- Brown, grey and yellow siltstone with abundant calcrete nodules and rare small gypsum crystals occurs intercalated with lenticular units of matrix-supported pebbly conglomerate.
- The formation is composed of red siltstones, containing discontinuous calcrete horizons, channelized sandstones and thin beds of current-rippled fine sandstone.
- The bottom of the rock has a layer of calcrete that tells us it was at one time exposed to air and it shows the transition between being exposed and becoming submerged.
- In a wash below the homesteads is a tool making site; discarded flints of granite, quartz and calcrete ornament the bare sandy soil.
- This calcrete can be three meters thick and looks like a breccia.
- Thin coals mark periods of swamp conditions on the floodplain, although some palaeosol profiles suggest relatively well-drained conditions, including a thin calcrete.
- Although calcrete nodules occur immediately below this fossil forest, the trees are rooted in a thin hydromorphic layer superimposed on top of the underlying well-drained soils.
Origin Early 20th century: from calc- + a shortened form of concrete. |