PLATE WITH VERY RARE HIRNANTIA FAUNA. GASTROPOD Holopea .ORDOVICIAN.PORTUGAL.Nºe

Description

<<<<  EXCELLENT AND  VERY RARE  PLATE
WHIT HIRNANTIA FAUNA. GASTROPOD AND BRIOZOA >>>>
Holopea
sp.
Upper Ordovician (hirnantian fauna) .Queixoperra Member of the Cabeço de Peao Formation. Amendoa-Maçao Area . Portugal.
EXCELLENT and very rare fossil
The
Hirnantian
is the seventh and final internationally recognized stage of the ordovician period of the paleozoic era. It was of short duration, lasting about 1.9 million years, from 445.2 ± 1.4 to 443.8 ± 1.5 Ma (million years ago). The early part of the Hirnantian was characterized by cold temperatures, major glaciation , and a severe drop in sea level. In the latter part of the Hirnantian, temperatures rose, the glaciers melted, and sea level returned to the same or to a slightly higher level than it had been prior to the glaciation.
Most scientists believe that this climatic oscillation caused the major extinction event that took place during this time. In fact, the Hirnantian (also known as the End Ordovician and the ordovician-silurian) mass extinction event represents the second largest such event in geologic history. Approximately 85% of marine (sea-dwelling) species died. Only the End permian mass extinction was larger. Unlike many smaller extinction events, however, the long-term consequences of the End Ordovician event were relatively small. Following the climatic oscillation, the climate returned to its previous state, and the species that survived soon (within two or three million years) evolved into species very similar to the ones that existed before.
Size plate: 6,7 x 4,6 x 2,3 cm.
weight: 80 g.
<>>
100% natural
Excellent detailing
Expenses shipment
:
For Europe: .99
For USA:  .99
===========================================================================
We combine shipping:
2018:
ITEMS
PESO/ WEIGHT
EUROPE
USA and other countries
to 80 gr
6,15  €
6,95 €
to 350 grs
10,20  €
13,95 €
to 820 kgrs
16,90  €
24,90 €
to 1600 Kgrs
27,00  €
29,90 €
to 2500 kgrs
31,00  €
34,99 €
to 3500 kgrs
35,00  €
39,99 €