Paleontological events: stratigraphic, ecologic, and evolutionary implications
نویسندگان
چکیده
منابع مشابه
The evolutionary diversification of cyanobacteria: molecular-phylogenetic and paleontological perspectives.
Cyanobacteria have played a significant role in Earth history as primary producers and the ultimate source of atmospheric oxygen. To date, however, how and when the group diversified has remained unclear. Here, we combine molecular phylogenetic and paleontological studies to elucidate the pattern and timing of early cyanobacterial diversification. 16S rRNA, rbcL, and hetR genes were sequenced f...
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anomolously low A1203, low Ti02 and are enriched in chromium and nick~A We present petrographic and chemical c ata on the Kamloops Lake picritic tmalts as we1 I as the stratigraphic setting for thwe ultramafic lavas. Age constraints derive From field relationships, Mineral chemistry indicates th 31 these ultramafic rocks represent mantle-deri.ed material which has undergone: minimal differentia...
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ژورنال
عنوان ژورنال: Eos, Transactions American Geophysical Union
سال: 1998
ISSN: 0096-3941
DOI: 10.1029/98eo00226