Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 1

Transcription

1 Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 1

2 Elements of Quaternary Geology Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 2

3 Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 3

4 The Quaternary is only 38 seconds long at this scale Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 4

5 Recall our analogy of all geologic time represented by a 24-hour clock the Quaternary is only 38 seconds long, but they are certainly important seconds, because during this time our species evolved Homo sapiens Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 5

6 1. Homo sapiens (Latin: "wise person") is the binomial nomenclature (also known as the scientific name) for the only extant human species. 2. Homo is the human genus, 3. H. sapiens is the only surviving species of the genus Homo. Modern humans are the subspecies Homo sapiens sapiens, which differentiates them from what has been argued to be their direct ancestor, Homo sapiens idaltu. 4. The ingenuity and adaptability of Homo sapiens has led to its becoming, arguably, the most influential species on the planet; Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 6

7 The Quaternary Period considers the topmost part of the Cenozoic Era. The Quaternary Period is divided into 2 epochs: - Pleistocene Epoch (1.8 mybp to 10,000 ybp) and QUATERNARY - Holocene Epoch (10,000 ybp to present). Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 7

8 Quaternary Chronostratigraphy Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 8

9 Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 9

10 The Pleistocene Epoch The Pleistocene is the first epoch of the Quaternary Period or sixth epoch of the Cenozoic Era The Pleistocene is the geological epoch which lasted from about million years before the present to 10,000 years ago, spanning the world's recent period of repeated glaciations. The Pleistocene deserves special attention It is the best-known glacial period (Ice Age) of the earth's history. The Pleistocene was a time of fluctuating colder climates that resulted in a number of extensive glaciations or ICE AGES. So, The Pleistocene is known as Pleistocene glaciations Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 10

11 The Pleistocene Epoch In geochronology, an epoch is a subdivision of the geologic timescale that is longer than an age and shorter than a period. We are currently living in the Holocene Epoch of the Quaternary Period. Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 11

12 Chronostratigraphy vs. Geochronology Chronostratigraphy (time-rock) Geochronology (time) Eonothem (e.g., Phanerozoic) Eon (e.g., Phanerozoic) Erathem (e.g., Mesozoic) Era (e.g., Mesozoic) System (e.g., Cretaceous) Period (e.g., Cretaceous) Series (e.g., Upper Cretaceous) Epoch (e.g., Late Cretaceous) Stage (e.g., Cenomanian) Age (e.g., Cenomanian) Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 12

13 The end of the Pleistocene corresponds with the end of the last glacial period. In the ICS timescale, the Pleistocene is divided into four stages or ages, Gelasian, Calabrian, Ionian Tarantian ICS International Classification for Standards All of these stages were defined in southern Europe. In addition to this international subdivision, various regional subdivisions are often used. Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 13

14 Subdivisions of the Quaternary System System Series Stage Age (Ma) Holocene Tarantian Quaternary Pleistocene Ionian Calabrian Gelasian Neogene Pliocene Piacenzian older Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 14

15 Global Boundary Stratotype Section and Point (GSSP) ICS (2007) recommends that IUGS establish the Quaternary as the uppermost System of the Cenozoic Erathem consistent with the usage of Quaternary by INQUA: 1) The Quaternary is a formal chronostratigraphic unit, the appropriate status for which is the System. The underlying System is the Neogene. 2) The base of the Quaternary is placed at the current base of GSSP Gelasian Stage (currently in the Pliocene) at the base of Marine Isotope Stage (MIS) 103, which has been calibrated to an age of ~2.6 Ma. 3) The base of the Pleistocene Series is lowered to coincide with that of the Quaternary System boundary (= Gelasian Stage GSSP). Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 15

16 There are many regional subdivisions for the Upper or Late Pleistocene; usually these represent locally recognized cold (glacial) and warm (interglacial) periods. The last glacial period ends with the cold Younger Dryas substage. The Pleistocene also corresponds with the end of the Paleolithic age used in archaeology. Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 16

17 The Younger Dryas, from c. 12,900 to c. 11,700 calendar years ago (BP), was a sharp decline in temperature over most of the northern hemisphere, at the end of the Pleistocene epoch, immediately preceding the current warmer Holocene. Map illustrating land cover over Europe and North Africa during the Younger Dryas event Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 17

18 Points to take home is defined by Desnoyers in 1829 is subdivided by Lyell 1839, into the Pleistocene and Holocene Epochs What is QUATERNARY? Pleistocene ( Lyell 1839) means most recent Holocene means wholly recent is a time of glacials and interglacials Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 18

19 is the most recent geological period of time in Earth s history, spanning the last two million years and extending up to the present day, What is QUATERNARY? is best known as the period of the ice ages. is characterized by a series of large-scale environmental changes that have deeply affected and shaped both landscapes and life on the Earth. is characterized by about of interglacial-glacial cycles. Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 19

20 Quaternary Geology For Geology BSc. Students, Tanta University, Ali Soliman 20