Comment on "Zircon thermometer reveals minimum melting conditions on earliest Earth" II.
نویسنده
چکیده
Watson and Harrison (Reports, 6 May 2005, p. 841) interpreted low temperatures (approximately 700 degrees C) for Hadean zircons as evidence of the existence of wet, minimum-melting conditions within 200 million years of solar system formation. However, high-temperature melts (approximately 900 degrees C) are zircon-undersaturated and crystallize zircon only after substantial temperature drop during fractional crystallization. Zircon thermometry cannot distinguish between low- and high-temperature Hadean igneous sources.
منابع مشابه
Zircon thermometer reveals minimum melting conditions on earliest Earth.
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ورودعنوان ژورنال:
- Science
دوره 311 5762 شماره
صفحات -
تاریخ انتشار 2006