| 释义 |
Siegenian, a. Geol.|siːˈgɛnɪən|
[f. Siegen, name of a town and region in North Rhine-Westphalia, W. Germany, + -ian.]
Pertaining to our designating a stage of the Lower Devonian in N.W. Europe, immediately above the Gedinnian, or the epoch or age during which it was deposited. Also absol.
1922Proc. Geologists' Assoc. XXXIII. 12 The higher horizon also includes many Siegenian species. 1928E. Neaverson Stratigraphical Palaeont. xi. 255 In Britain..the Siegenian stage is best represented by the Meadfoot beds of South Devon. 1931[see Famennian a.] 1967M. R. House in W. B. Harland et al. Fossil Record i. 47 The goniatites appear in the mid-Siegenian as simple primitive types which soon diversify rapidly. 1979R. Anderton et al. Dynamic Stratigr. Brit. Isles x. 130/2 Non-marine faunas of ostracoderm and placoderm fish fragments and plant remains..indicate a lower Devonian (Siegenian) age for the group. |