| mhorn | Дата: Saturday, 06.06.2009, 12:24 | Сообщение # 1 |
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| Stevens G.R. (2007) The ammonite genus Harpoceras (Early Jurassic) in New Zealand // New Zealand Journal of Geology & Geophysics, Vol. 50. P.377–386.
pdf: http://www.royalsociety.org.nz/includes/download.aspx?ID=91552
Harpoceras subplanatum (Oppel, 1856) is recorded from two localities in the North Island of New Zealand. The localities occur in strata of the Ururoan Stage of the New Zealand local stage sequence, correlated internationally with the Pliensbachian and Toarcian. Elsewhere in the world, notably in Europe and South America, H. subplanatum occurs in the Bifrons Zone of the Early Toarcian, ranging throughout
the middle and upper parts of the Fibulatum Subzone. The presence of H. subplanatum in New Zealand provides an international correlation point for the middle of the Ururoan Stage. Harpoceras subplanatum achieved a wide distribution in Europe, extending from England to the Caucasus. It also became distributed in the circum-Pacific region with occurrences in North and South America, Japan, and New Caledonia. The New Zealand occurrences are considered to be a component of this circum-Pacific distribution. The widespread distribution of H. subplanatum was probably facilitated by the availability of various migratory seaways (e.g., Viking and Hispanic Corridors), made more accessible by the Early–Middle Toarcian eustatic rise in sea level.
Middle Jurassic - Lower Cretaceous ammonites & aptychi
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