TIMPUL GEOLOGIC Istoria geologica a Pamantului PLAN- GHID pe baza caruia se va realiza proiectul /ggp/01.%20GEOLOGIE%20GENERALA%20-%20PREZENTARE%2001%20- %20Notiuni%20introductive.pdfhttp://doru.juravle.com/cursuri/resurse/cursuri_ /ggp/01.%20GEOLOGIE%20GENERALA%20-%20PREZENTARE%2001%20- %20Notiuni%20introductive.pdf TEMA 16 TIMPUL GEOLOGIC

EVOLUTIA PALEOGEOGRAFICA A TERREI l

EVOLUTIA VIETII PE TERRA

1. GEOCRONOLOGIE Geocronologia este o ramura a stratigrafie care se ocupa cu datarea (stabilirea vârstei) depozitelor geologice si ierarhizarea cronologica a acestora, rezultând unitai geocronologice (de timp), concretizate în unitai cronostratigrafice. Datarea se poate face –relativ, aplicându-se corelarile pornind de la principiul superpoziei geometrice a stratelor si evoluiei organismelor biologice –în mod absolut, folosindu-se metode radiometrice. Unitati geocronologice: EON, ERA, PERIOADA, EPOCA, VARSTA, CRON

DATAREA PRIN METODE RADIOMETRICE Vârste absolute

EonEraPerioada inceput - sfarsit (mil.ani) Phanerozoic Eon: PH Cenozoic Era: CZ Neogen N Paleogen E Mesozoic Era: MZ Cretacic K Jurasic J Triasic T Paleozoic Era: PZ Permian P Carbonifer C Devonian D Silurian S Ordovician O Cambrian Є Precambrian: Prc Proterozoic PR Arhaic AR Hadean HAc Chaotian CHc TIMPUL GEOLOGIC

Istoria geologica a Pamantului

I EONUL PRECAMBRIAN II. EONUL FANEROZOIC

EONERASPAN (Mya)Notes and Events Proterozoi c Paleoproteroz oic mya More or less conventional plate tectonics Archean Neoarchean mya First large continental shields Mesoarchea n mya First widely-accepted fossil evidence of life. First banded iron formations. Paleoarchea n mya First stromatolites? Formation of relatively stable crust units (possibly even earlier, but see generally negative review. Eoarchean ~ mya Debatable geochemical evidence for life (no longer widely accepted) Hadean Early Imbrian mya Late heavy bombardment of Earth-moon system. I. EONUL PRECAMBRIAN -CARACTERIZARE ARHAIC (The Archean Eon : )

2. PROTEROZOIC- CARACTERIZARE Geografia Proterozoicului – 2 Viata in Proterozoic –

eoneraperioada A inceput acum (mil ani) Durata (mil ani) Fanerozoic 3 Neozoic (Cenozoic) Neogen23.0 Paleogen Mezozoic Cretacic Jurasic20054 Triasic Paleozoic Permian29948 Carbonifer35960 Devonian41657 Silurian44428 Ordovician48844 Cambrian54254 II. EONUL FANEROZOIC

II EONUL FANEROZOIC Erele: Paleozoic, Mezozoic, Neozoic ERA PALEOZOIC -CARACTERIZARE Geografia Paleozoicului (imagini, harti) Viata in Paleozoic (desene) –Of the three main eras that make up the Phanerozoic, the Paleozoic is the longest and most diverse, spanning the period from very early multicellular life that only inhabited the oceans to quite advanced tetrapods* and reptiles and extensive forests on land.tetrapods*reptiles – Early Paleozoic: Age of Invertebrates Coelomate radiation (Cambrian explosion) - origin of major groups of organisms; nervous system, behavior patterns and simple consciousness (the nascent Noosphere); continents drift apart. –Middle Paleozoic: Age of Fish Tropical conditions. Extinction of many "experimental" animal groups; diversification of surviving invertebrate groups, rise of vertebrates (fish). Life moves on land (rhyniophytes, lycophytes, uniramous arthropods, proto-amphibians).invertebratevertebratesrhyniophytes lycophytesuniramous arthropodsproto-amphibians –Late Paleozoic: Age of Tetrapods* and Reptiles Ice age. Coal forests of giant lycopsids, calamites, pteridophytes and ferns cover the tropical landmasses. Southern landmass of Gondwanaland buried under glaciers; continents drift together. Reptiles conquer the landReptiles

ERA MEZOZOIC –CARACTERIZARE DESCRIERE imagini, harti Geografia Mezozoicului Viata in Mezozoic(desene) –The Mesozoic has been called the "age of reptiles", but "age of dinosaurs" would be more appropriate. There is still controversy over whether dinosaurs really were stupid sluggish ectotherms ("reptiles") or active high-metabolism (endotherm) creatures more like birds. Even if we define them as "reptiles" the age of reptiles as such begins in the Permian period of the Paleozoic era anyway.reptilesdinosaursbirds –Tropical (Greenhouse) Conditions. Pangaea continues during the early Triassic; then landmasses begin to drift apart. Shallow oceans cover much of the continents, breaking the land into large islands. Mammals remain small, possibly nocturnal. Most modern groups of organisms appear. Vertebrate animals (mammals, birds, theropod dinosaurs) develop larger brains then their earlier reptilian ancestors.Mammalsbirdstheropod dinosaurs