Age dating of basalt leonardo dicaprio dating profile
Reference: Knowing precisely when major rock types formed during construction of the lunar crust builds a quantitative framework for understanding the origin and geochemical evolution of the lunar highlands.For example, a cherished idea in lunar science is that the Moon melted when it formed.We need a way to assess the probability that a rock's apparent age is correct.This is what Lars Borg and his colleagues set out to do.Unfortunately, ages of lunar samples obtained over the past decades scatter annoyingly and do not allow a straightforward chronological test of the sequence of crust formation.In fact, the data suggest that the anorthosites and magnesian rocks overlap in age, but many of the ages are not determined well—a fault with the rocks, not the isotopic analyses, although geochronological techniques have improved over the years.This is essentially the same as the so-called model ages of the formation of KREEP (a chemical component enriched in potassium, rare earth elements, and phosphorous) and of the formation of the deep source regions that melted to produce mare basalts.
The upper 10–20 kilometers of the lunar highlands is a mixed-up pile of rocky rubble formed when the Moon was bombarded early in its history by countless planetesimals.
The lighter minerals (predominately plagioclase feldspar) formed the primary crust of the Moon.
[Below] After formation of the feldspar-rich crust, the sunken dense minerals partially melted and formed the magnesian suite of rocks now found as intrusions in the plagioclase-rich crust and the basalt lava flows that make up the maria.
The rock has a distinctively fragmental appearance, not an igneous texture, although in places in other pieces of 60025 a good igneous texture is seen easily.
The rock has been affected by one or more impacts, but in spite of its fragmentation it is possible to extract a reliable age from it. In fact, geochronologists can determine the time when the metamorphism took place if the temperature was hot enough for long enough to reset chronometers.