Mr. Varner Reference and vocabulary activity Geologic Time: Paleogeographic terms Objective: To learn important terms used in studying changes in the earth's continents, and to prepare for projects focusing on geologic periods. Materials: Internet access, or reference books such as scientific encyclopedias. Procedure: ¥ Define the following terms used extensively in studying the earth's geologic history. Give ages for any continents or oceans in millions of years (Ma) if provided. ¥ Attach definitions on notebook paper or typed to this sheet. Arctica Avalonia Baltica *Columbia (supercontinent), also called Nuna craton Euramerica, also called Laurussia glaciation Gondwana Iapetus Ocean Kazakhstania Kenorland Laurasia Laurentia Nena (supercontient) *North China (continent), also called North China craton Paleo-Tethys Ocean Panafrican Ocean Pangaea Pannotia Panthalassic Ocean, also called Panthalassa Proto-Laurasia Proto-Tethys Ocean Rheic Ocean Rodinia *Siberia (continent) *South China (continent), also called South China craton or Yangtze craton terrane Tethys Ocean, or Tethys Sea *Ur (supercontinent) Vaalbara * Note: make sure your definitions relate to ancient geologic history and not to more recent historical periods, countries, or politics.