The Radiometric Dating Game Radiometric dating methods estimate the age of rocks using calculations based on the decay rates of radioactive elements such as uranium, strontium, and potassium. On the surface, radiometric dating methods appear to give powerful support to the statement that life has existed on the earth for hundreds of millions, even billions, of years. We are told that these methods are accurate to a few percent, and that there are many different methods. We are told that of all the radiometric dates that are measured, only a few percent are anomalous. This gives us the impression that all but a small percentage of the dates computed by radiometric methods agree with the assumed ages of the rocks in which they are found, and that all of these various methods almost always give ages that agree with each other to within a few percentage points. Since there doesn’t seem to be any systematic error that could cause so many methods to agree with each other so often, it seems that there is no other rational conclusion than to accept these dates as accurate. However, this causes a problem for those who believe based on the Bible that life has only existed on the earth for a few thousand years, since fossils are found in rocks that are dated to be over million years old by radiometric methods, and some fossils are found in rocks that are dated to be billions of years old.
Rubidium—strontium method The radioactive decay of rubidium 87Rb to strontium 87Sr was the first widely used dating system that utilized the isochron method. Because rubidium is concentrated in crustal rocks, the continents have a much higher abundance of the daughter isotope strontium compared with the stable isotopes. A ratio for average continental crust of about 0. This difference may appear small, but, considering that modern instruments can make the determination to a few parts in 70, , it is quite significant.
Dissolved strontium in the oceans today has a value of 0. Thus, if well-dated, unaltered fossil shells containing strontium from ancient seawater are analyzed, changes in this ratio with time can be observed and applied in reverse to estimate the time when fossils of unknown age were deposited.
Ice cores are one of the most effective, though not the only, methods of recreating long term records of temperature and atmospheric gases. Particularly in the polar region, but also at high elevations elsewhere, snow falls on an annual cycle and remains permanently.
But in the past witches were thought to be real — and believers found them everywhere. From the 15th to 18th century more than , — usually innocent victims of mass paranoia — were tortured, burned or hanged all over Europe. But how, exactly, did accusers spot their targets? Here are the most bizarre and terrifying examples of how to identify your witch Do they look like a witch? The suspect was sprinkled with holy water, stripped to her undergarments then trussed up with her right thumb tied to her left big toe and vice versa.
With a rope around her waist she was tossed into a pond or river. If she floated, she was a witch, if she sank she could be hauled out and saved The theory was that witches reject the sacrament of baptism so water rejects their bodies.
Unreliability of Radiometric Dating and Old Age of the Earth
Forget finding love, dating apps are now for finding friends. The answer is complicated — just like the relationships that often spring from these apps. There are still plenty of people out there in search of the perfect match, but the dating app Hater , which matches people based on the things they mutually dislike, has discovered an interesting trend among its users.
Hater, the app that lets you find love based on what you hate When the app first launched back in February, it got a lot of international attention, with people signing up in many different countries. It may sound counterintuitive given that people usually go on dating apps to find people in their vicinity, but it was a hit.
An ice core is a core sample that is typically removed from an ice sheet or a high mountain the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper, and an ice core contains ice formed over a range of years.
Ice-sheet dynamics Sampling the surface of Taku Glacier in Alaska. There is increasingly dense firn between surface snow and blue glacier ice. An ice core is a vertical column through a glacier, sampling the layers that formed through an annual cycle of snowfall and melt. At Summit Camp in Greenland, the depth is 77 m and the ice is years old; at Dome C in Antarctica the depth is 95 m and the age years.
The bubbles disappear and the ice becomes more transparent. Ice is lost at the edges of the glacier to icebergs , or to summer melting, and the overall shape of the glacier does not change much with time. These can be located using maps of the flow lines. These include soot, ash, and other types of particle from forest fires and volcanoes ; isotopes such as beryllium created by cosmic rays ; micrometeorites ; and pollen.
It can be up to about 20 m thick, and though it has scientific value for example, it may contain subglacial microbial populations ,  it often does not retain stratigraphic information. In polar areas, the sun is visible day and night during the local summer and invisible all winter. It can make some snow sublimate , leaving the top inch or so less dense.
When the sun approaches its lowest point in the sky, the temperature drops and hoar frost forms on the top layer.
How do ice cores work? Current period is at right. From bottom to top: Milankovitch cycles connected to 18O.
Clearly visible in the canyon walls are the light-colored granites, such as the Zoroaster Granite, which are stark against the darker, folded strata of the Vishnu Schist and the other metamorphic rock units of the Granite Gorge Metamorphic Suite1 see lowest purple and green shading in diagram. These are former sedimentary and volcanic strata that have been transformed by heat and pressure, possibly during the intense upheavals when the dry land was formed on Day 3 of Creation Week.
These were originally basalt lava flows several meters to tens of meters thick. In some outcrops pillow structures have been preserved, testimony to the basalt lavas having originally erupted and flowed under water onto the Creation Week ocean floor. Metamorphic rocks are not always easy to date using radio-isotopes. Results obtained usually signify the “date” of the metamorphism, but they may also yield the “age” of the original volcanic or sedimentary rock. The “age” or “date” is calculated from the amount of the daughter isotope produced by radioactive decay of the parent isotope.
In Grand Canyon, the “date” of metamorphism of the basalt lavas to form these Brahma amphibolites has been determined as Ma million years ago , based on U-Pb dating of minerals in the overlying Vishnu Schist and underlying Rama Schist that formed during the metamorphism. These included seven samples from a meter long and 2 meter wide amphibolite body outcropping just upstream from the mouth of Clear Creek at river mile 84 measured from Lees Ferry.
All 27 samples were sent to two well-credentialed internationally-recognized, commercial laboratories for radioisotope analyses—potassium-argon K-Ar at a Canadian laboratory, and rubidium-strontium Rb-Sr , samarium-neodymium Sm-Nd , and lead-lead Pb-Pb , at an Australian laboratory. Both laboratories use standard, best-practice procedures on state-of-the-art equipment. Results The model K-Ar ages for each of the samples ranged from Furthermore, the seven samples from the small amphibolite unit near Clear Creek, which should all be the same age because they belong to the same metamorphosed basalt lava flow, yielded K-Ar model ages ranging from
The Hockey Stick: A New Low in Climate Science
It made sense to worry that carbon dioxide did influence temperature. But by new data came in and it was clear that carbon lagged behind temperature. The link was back to front. After temperatures rise, on average it takes years before carbon starts to move.
Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed. The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
Particularly in the polar region, but also at high elevations elsewhere, snow falls on an annual cycle and remains permanently. Over time, a few decades, the layers of snow compact under their own weight and become ice. By drilling through that ice, and recovering cylinders of it, it is possible to reconstruct records of temperature and of atmospheric gases for periods of hundreds of thousands of years. Technologically the recovery of ice cores and their analysis is an amazing feat.
Secondly, to analyse the content of the air bubbles, and determine not only the proportion of different gases but also the proportion of specific isotopes of those gases is also technologically challenging. Whilst ice cores allow direct measurement of atmospheric gases, like CO2 and Methane, some care is needed in interpreting the results. This is because of the fact that, while the snow is being compressed into ice, gas transfer may occur between the atmosphere and the layers of ice.
Age of the Earth: strengths and weaknesses of dating methods
Glacials are colder phases within an ice age in which glaciers advance; glacials are separated by interglacials. Thus, the end of the last glacial period, which was about 11, years ago, is not the end of the last ice age since extensive year-round ice persists in Antarctica and Greenland. Over the past few million years the glacial-interglacial cycles have been “paced” by periodic variations in the Earth’s orbit via Milankovitch cycles.
Although radiometric dating of ice cores has been difficult, Uranium has been used to date the Dome C ice core from Antarctica. Dust is present in ice cores, and it contains Uranium.
First, some preliminary remarks are given: It is the local or global mean height of sea level. How is MSL defined: This definition averages out tidal highs and lows caused by the changing effects of the gravitational forces from the moon and sun”. Mean Sea Level cannot be measured directly. It must be derived from other measurements such as hourly tide gauge measurements or proxy data sea level marks.
The height of Mean Sea Level is given relative to a certain, arbitrary chosen, reference or datum level, e. Mean Sea Level may rise or fall, relative to the zero point of the reference scale. The zero point itself is meant to be stable over time. This greatly complicates the problem of determining global sea level change from tide gauge data From: Tide gauge sea level.
Ice core basics
Are we headed for a new ice age? By Phil Plait June 17, 6: Can this mean the Earth itself will literally cool off, slipping into an ice age? The answer — spoiler alert! And if you have the attention span of an E. One in particular was Caspar Ammann , who was very helpful in explaining the solar connection with the Little Ice Age to me.
Clear physical evidence of the existence of the Little Ice Age and theMedieval Warm Period. Claims to the contrary are false.
You try and try and try to explain, but no one ever understands. No one who’s not a Warlock. Who hasn’t spent a dozen years scouring the ruins for one string of symbols, one clean code, one black talon. Titans just make a hmphing noise, if they’ve stayed awake. Hunters clean their nails with their knives and look at you like you’ve grown a third eye. But when you’ve spent your life searching through arcana for ancient power, you have the urge to reach out and educate others.
Especially if you’ve had one too many. Nah, she’s not my type at all. We’ve played dice, cards, war games, you know, the usual stuff. I’d never tried to show off before. I don’t know what came over me. I had a broken vertebrae in my pocket that I’d borrowed from – yes, borrowed, I was going to put it back – what do you think you are, my conscience?
It was a fossil, that means mineral replacement, a rock, basically. They can survive a few hours in my pocket.