The earth has been determined by radiometric dating to be
The Rb-Sr dating method has been used extensively in dating terrestrial and lunar rocks, and meteorites.If the initial amount of Sr is known or can be extrapolated, the age can be determined by measurement of the Rb and Sr concentrations and the Sr ratio. Development of this process was aided by German chemists Otto Hahn and Fritz Strassmann, who later went on to discover nuclear fission in December 1938.The utility of the rubidium–strontium isotope system results from the fact that Sr with a half-life of 48.8 billion years.The dates indicate the true age of the minerals only if the rocks have not been subsequently altered.The important concept in isotopic tracing is that Sr derived from any mineral through weathering reactions will have the same Sr as the mineral.Thus, assigning age significance to a result requires studying the metasomatic and thermal history of the rock, any metamorphic events, and any evidence of fluid movement.A Rb-Sr date which is at variance with other geochronometers may not be useless, it may be providing data on an event which is not representing the age of formation of the rock.
Rubidium substitutes for potassium within the lattice of minerals at a rate proportional to its concentration within the melt.
In addition, Rb is a highly incompatible element that, during partial melting of the mantle, prefers to join the magmatic melt rather than remain in mantle minerals. The radiogenic daughter, Sr, is produced in this decay process and was produced in rounds of stellar nucleosynthesis predating the creation of the Solar System.
Different minerals in a given geologic setting can acquire distinctly different ratios of radiogenic strontium-87 to naturally occurring strontium-86 (Sr as the parent melt.
If we add up the dates from Adam to Abraham, we get about 2,000 years, using the Masoretic Hebrew text of Genesis 5 and 11.3 Whether Christian or secular, most scholars would agree that Abraham lived about 2,000 B. Quite a few people have done this calculation using the Masoretic text (which is what most English translations are based on) and with careful attention to the biblical details, they have arrived at the same time frame of about 6,000 years, or about 4000 B. Two of the most popular, and perhaps best, are a recent work by Dr. The first four in table 2 (bolded) are calculated from the Septuagint, which gives ages for the patriarchs’ firstborn much higher than the Masoretic text or the Samarian Pentateuch (a version of the Old Testament from the Jews in Samaria just before Christ).
Floyd Jones4 and a much earlier book by Archbishop James Ussher5 (1581–1656). The misconception exists that Ussher and Jones were the only ones to arrive at a date of 4000 B. Jones6 lists several chronologists who have undertaken the task of calculating the age of the earth based on the Bible, and their calculations range from 5501 to 3836 B. Because of this, the Septuagint adds in extra time.