norseman Posted October 28, 2022 Admin Author Posted October 28, 2022 4 minutes ago, Incorrigible1 said: In such a case, the age estimation would widen. It's science (little "s",) it questions itself. I found this. I don’t know why? But I find biology much more interesting than geology. https://geology.utah.gov/map-pub/survey-notes/glad-you-asked/glad-you-asked-how-do-geologists-know-how-old-a-rock-is/ 1
Incorrigible1 Posted October 28, 2022 Posted October 28, 2022 Quoting now: Faunal Dating The term faunal dating refers to the use of animal bones to determine the age of sedimentary layers or objects such as cultural artifacts embedded within those layers. Scientists can determine an approximate age for a layer by examining which species or genera of animals are buried in it. The technique works best if the animals belonged to species, which evolved quickly, expanded rapidly over a large area, or suffered a mass extinction. In addition to providing rough absolute dates for specimens buried in the same stratigraphic unit as the bones, faunal analysis can also provide relative ages for objects buried above or below the fauna-encasing layers. Pollen Dating (Palynology) Each year seed-bearing plants release large numbers of pollen grains. This process results in a “rain” of pollen that falls over many types of environments. Pollen that ends up in lakebeds or peat bogs is the most likely to be preserved, but pollen may also become fossilized in arid conditions if the soil is acidic or cool. Scientists can develop a pollen chronology, or calendar, by noting which species of pollen were deposited earlier in time, that is, residue in deeper sediment or rock layers, than others. The unit of the calendar is the pollen zone. A pollen zone is a period of time in which a particular species is much more abundant than any other species of the time. In most cases, this tells us about the climate of the period, because most plants only thrive in specific climatic conditions. Changes in pollen zones can also indicate changes in human activities such as massive deforestation or new types of farming. Pastures for grazing livestock are distinguishable from fields of grain, so changes in the use of the land over time are recorded in the pollen history. The dates when areas of North America were first settled by immigrants can be determined to within a few years by looking for the introduction of ragweed pollen. Pollen zones are translated into absolute dates by the use of radiocarbon dating. In addition, pollen dating provides relative dates beyond the limits of radiocarbon (40, 000 years), and can be used in some places where radiocarbon dates are unobtainable. Fluorine is found naturally in ground water. This water comes in contact with skeletal remains under ground. When this occurs, the fluorine in the water saturates the bone, changing the mineral composition. Over time, more and more fluorine incorporates itself into the bone. By comparing the relative amounts of fluorine composition of skeletal remains, one can determine whether the remains were buried at the same time. A bone with a higher fluorine composition has been buried for a longer period of time. https://www.encyclopedia.com/social-sciences-and-law/anthropology-and-archaeology/archaeology-general/dating-techniques 1
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