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11.
M.R.G. Sayyed 《地学前缘(英文版)》2014,5(6):791-799
Since continental sediments (in addition to the marine geological record) offer important means of deciphering environmental changes, the sediments hosted by the successive flows of the continental flood basalt provinces of the world should be treasure houses in gathering the palaeoclimatic data. Palaeosols developed on top of basalt flows are potentially ideal for palaeoenvironmental reconstructions because it is easy to determine their protolith geochemistry and also they define a definite time interval. The present paper summarizes the nature of the basalt-hosted palaeosols formed on the flood basalts provinces from different parts of the ~lobe havin~ different ages. 相似文献
12.
Sayyed Ahang Kowsar 《山地科学学报》2005,2(3):233-243
1 Introduction A desert is defined as a large area of barren land, waterless and treeless, often sand-covered (Oxford Advanced Learner’s Dictionary of Current English 1974). The presence of numerous, sometimes prosperous agricultural communities in the so-called deserts defies this definition. The land is not necessarily barren; leaching of nutrients that causes certain deficiencies in the soils of humid environments hardly occurs in deserts. The most apparent deficiencies for crop product… 相似文献