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Paleozoic era

(Encyclopedia)Paleozoic era pāˌlēəzōˈĭk [key], a major division (era) of geologic time (see Geologic Timescale, tablegeologic timescale, table) occurring between 570 to 240 million years ago. It is subdivide...

era

(Encyclopedia)era, period of historic time. In geology, it is the name applied to large divisions of geological process, e.g., Paleozoic era (see geology). In chronology an era is a period reckoned from a fixed poi...

Mesozoic era

(Encyclopedia)Mesozoic era mĕzˌəzōˈĭk [key] [Gr.,=middle life], major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 65 to 225 million years ago. Great crustal disturb...

Cenozoic era

(Encyclopedia)Cenozoic era sēnəzōˈĭk, sĕn– [key], last major division of geologic time (see Geologic Timescale, tablegeologic timescale, table) lasting from 65 million years ago to the present. The Cenozoic...

Siberian Platform

(Encyclopedia)Siberian Platform or Angara Shield, large, geologically stable area of Precambrian rocks, N Asia, comprising much of Siberia, Russia. It is bounded, in general, on the west by the Yenisei River, on th...

White Mountains

(Encyclopedia)White Mountains, part of the Appalachian system, N N.H. and SW Maine, rising to 6,288 ft (1,917 m) at Mt. Washington in the Presidential Range and to 5,249 ft (1,600 m) at Mt. Lafayette in the Francon...

era of good feelings

(Encyclopedia)era of good feelings, period in U.S. history (1817–23) when, the Federalist party having declined, there was little open party feeling. After the War of 1812 all sections were anxious to return to a...

Permian period

(Encyclopedia)Permian period pûrˈmēən [from Perm, Russia], sixth and last period of the Paleozoic era (see Geologic Timescale, tablegeologic timescale, table) from 250 to 290 million years ago. Many marine a...

Triassic period

(Encyclopedia)Triassic period trīăsˈĭk [key], first period of the Mesozoic era of geologic time (see Geologic Timescale, tablegeologic timescale, table) from 205 to 250 million years ago. Throughout the Triassi...

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