using fossils to establish relative timescale Flashcards
rugose coral peak
carboniferois
tabulate coral peak
Silurian and devonian
long hinged brachiopod indicate which era
Mesozoic
LONG hinged brachiopod indicates which era
paleozoic
SHORT hinged brachiopod indicates which era
Mesozoic and younger
interesting point about bivalves and brachiopods
bivalves occupied brachiopod niches after permo-triassic when brachiopod numbers dwindled
goniatites indicate which periods
Devonian - Permian
ceratites indicate which periods
Permian
ammonites indicate which periods
Triassic - cretaceous
trilobites indicate which era
Palaeozoic
graptolites indicate which era
palaeozoic
graptolites abundant in which period
Ordovician and silurian
which era were echinoid more abundant although they (regular) have been around since cambrian
Mesozoic and younger