We Were Wrong About Isochrons, Geologists Say

[barnabas]

An isochron (a word meaning "equal time") is supposed to be a line connecting points on a graph that represent the same age, or the same age difference. If your rain gutter barrel fills fast and the bucket in your garage fills slowly, for instance, you can figure the time the rain started if you know their individual fill rates; the line connecting those two points on a graph would be an isochron. If you found another bucket and its fill rate also fell on the line, it would imply it started filling at the same time. As straightforward as this method is at home or in the lab, can it be misleading when extrapolated millions of years into the past, when the initial and intervening conditions were not subject to observation?

When geologists date rocks, they seek to identify minerals that are isochronous, though they may decay at different rates. A hidden assumption was that the initial isotope ratios were fixed at the time the rock formed. Not so fast, say four geologists from the UK, Wisconsin and California, writing in Geology:1

The determination of accurate and precise isochron ages for igneous rocks requires that the initial isotope ratios of the analyzed minerals are identical at the time of eruption or emplacement. Studies of young volcanic rocks at the mineral scale have shown this assumption to be invalid in many instances. Variations in initial isotope ratios can result in erroneous or imprecise ages. (Emphasis added in all quotes.)

This realization

[Leonard]

You know what happens when you 'assume' something......

[Bread_of_Life]

There are a few ways in which isochrons can be formed in a rock that is not very old.

The first is mixing - if a rock is formed from the melting and mixing of two rocks this always gives an isochron, called a mixing isochron. This isochron can have a positive or negative slope (so half of mixing isochrons are easily found, because they give a negative age). The other half (positive mixing isochrons) can be compared to other dating techniques, which will typically not agree - or there is a mathematical test to find out which are and which are not mixing isochrons.

The other main form of "false" isochron is an inherited isochron - where a very old rock with a pre-existing isochron is part melted and solidifies, and the new rock that is formed partially inherits the old rock's isochron. Of course, this takes a rock of very significant age to start with, so it is of little interest to creationists. Also, it can be spotted by comparing with other dating methods, and by examining the rock, and carefully choosing a sample.

The only other form is a metamorphic isochron, where a rock is part melted, and the melted part gets a different isochron to the solid part. These are again usually quite easy to spot, because they often lead to two different isochrons, one the age of the rock, and one the time of the metamorphic event.

None of these present a significant challenge to geochronology. Out of hundreds of thousands of samples dated so far, there have only been a few tens of mixing isochrons reported. The majority of samples are real isochrons, and there is generally good agreement with several different forms of radio-metric dating methods. Sorry, try again.

[Sola Scriptora]

"The church says the earth is flat, but I know that it is round, for I have seen the shadow on the moon, and I have more faith in a shadow than in the church."

Fog:

The "church" said no such thing. The Roman Catholic Cult said those things, not real Christians. The BIBLE TOLD US 2700 years ago that the world was ROUND--A CIRCLE. So the poor persecuting dupes at the Vatican were wrong, that's all. Get your facts, or the lack thereof, straight.

[JLW001]

"The church says the earth is flat, but I know that it is round, for I have seen the shadow on the moon, and I have more faith in a shadow than in the church."

Fog:

The "church" said no such thing. The Roman Catholic Cult said those things, not real Christians. The BIBLE TOLD US 2700 years ago that the world was ROUND--A CIRCLE. So the poor persecuting dupes at the Vatican were wrong, that's all. Get your facts, or the lack thereof, straight.

<{POST_SNAPBACK}>

unfortunately for you without the Roman Catholic "cult" there would be no Christianity. I think even Shiloh makes better arguments than you, no, I'm certain of it.

"At a conservative estimate, ten million witches were killed throughout Europe. . . . The decline of witch-belief was . . . entirely the product of religious scepticism. . . . The Catholic Church did not reform itself on this matter; it was forced by outside pressure to reform. To be sure, the Protestant churches were no better in this regard; it is simply that they had less time - only two or three centuries - to engage in the torching of witches. After all, John Wesley, the founder of Methodism, stated quite correctly that disbelief in witches meant a disbelief in the Bible." S. T. Joshi

<{POST_SNAPBACK}>

What exactly is your argument? That all Christians are at fault for what the Catholic church did? Are we guilty by some distant association?

How is it that you have knowledge that God's Church only survived by the Catholic religion? Are there other ways it could have survived or did survive?

If someone or some organizations deny what is written within the Bible, then they are not Christians.

[Sola Scriptora]

Nonsense, we owe nothing to Rome there Foggy, except that they produced confused and embittered people like you who saw the evil and hypocrisy, and wrongly concluded Christianity must not be true, look at its adherents! You are looking at the wrong group--this one we were warned about in the Bible--Rev 17.

As for burning witches--you guys forget something. The pilgrim fathers founded a nation and made laws. They forbade witchcraft as well as kidnapping, stealing etc. If someone wanted to live in this new nation, its understood they had to obey the laws of the land. Witchcraft was against the law and a capital offense. To our pilgrim fathers, this behavior was an affront to God and would bring His displeasure upon the nation. If the witches didn't like it, they just could have left. Don't blame the pilgrims for following through with their laws.

The Catholic cult on the other hand, persecutes anyone who doesn't agree with her. The pilgrim fathers founded a nation and set the laws. This is different. For you to be consistent, you would ALSO have to condemn them for punishing thieves, perjurers, murderers, etc. They had the right to establish this nation any way they wanted. Witches were not welcome. They took their chances, and paid the price for defying the civil government they lived in.

Edited January 30, 2005 by Sola Scriptora

[JLW001]

"The U.S. has more churchgoing than any other major democracy and it reports much higher rates of murder, rape, robbery, shootings, stabbings, drug use, unwed pregnancy, and the like, as well as occasional tragedies such as those at Waco and Jonestown. . . . There may be no link between the two conditions, but the saturation of religion has failed to prevent the severe crime level. . . . Societies rife with fundamentalism and religious tribalism are prone to sectarian violence. In contrast, England, Scandinavia, Canada, Japan, and such lands have scant churchgoing, yet their people are more inclined to live peaceably, in accord with the social contract. The evidence seems clear: To find living conditions that are safe, decent, orderly, and 'civilized,' avoid places with intense religion."

-James Haught

<{POST_SNAPBACK}>

Number 1: All Americans are not Christians, even though I wish they were.

Number 2: Just because someone goes to church doesn't mean they are Christian.

Number 3: Can Mr James Haught back those suppositions up with numbers from reputable sources. One more thing. Yes we may have more murders in America than you have in any given nation in the EU, but what of the murder rate per capita? Hmmm. You can substitute any particular vice or crime you like for murder in the above sentence:)

Edited January 30, 2005 by JLW001

[Bread_of_Life]

How on earth did a rather dry subject like isochrons so quickly become a debate about catholicism.

Oh, and by the way, the definition of a circle is:

n. A plane curve everywhere equidistant from a given fixed point, the center.

Of course, a plane curve is necessarily 2D, according to our definition of a plane. in other words, circles are, by definition, 2 dimensional. Therefore to say that:

The BIBLE TOLD US 2700 years ago that the world was ROUND--A CIRCLE.

is accurate to the extent that circles are round, but inaccurate to the extent that it does not show that the earth is 3 dimensional, but rather implies that it is flat and planar.

[Bread_of_Life]

lol, it's cool, I shared my info in my original post on this topic, which was duly ignored. I can't really be bothered trying again!

[irishcowboy]

What exactly is your argument? That all Christians are at fault for what the Catholic church did?