The early history of our planet poses many scientific conundrums, for creationists as well as evolutionists. The following list is a sample, highlighting some of the most fundamental problems:

• Why are there no rocks dating to the first 700 million years of Earth’s history (called the Hadean)? Most of the Moon’s rocks date to that period, but not the Earth’s. The only remains are tiny, rare, zircon crystals.
• Those crystals tell us that there was abundant water on the primeval Earth. Where did the water come from?
• Towards the end of the Hadean the Earth-Moon system was bombarded by a storm of asteroids. It was so intense that it left the Moon’s surface saturated with craters. Most of the Earth’s oceans would have evaporated as a result of the energy released, yet the oldest rocks on Earth, immediately after this cataclysm, show that there was still abundant water on the planet.
• When and how did the first forms of life evolve into existence? Credible explanations for the ‘origin of life’ still elude us, and the earliest evidence is controversial.
• Since there were oceans from 3.8 to at least 1.8 billion years ago, why were they not frozen over? According to astronomers, the Sun 3.8 billion years ago radiated only 75% of the heat it gives out today.
• Why were the oceans throughout that time not only not cold, but much warmer than today?

Some of these points are discussed on the website Earth History: A New Approach. Here we will just say a little about the last two.

The first of these is known as ‘the faint young sun problem’ (or ‘paradox’ as some prefer to call it). According to current ideas about how stars evolve, stars with the same mass as the Sun’s gradually become warmer and brighter (as shown in the figure). At the time of the oldest rocks the Earth’s oceans would have been frozen over, and would have remained so for much of its history.



We know from geological evidence, however, that the Earth was not frozen over. So how do we resolve the problem? One approach is to look for some ‘fix’, such as the hypothesis that there was much more methane or carbon dioxide in the atmosphere then than we previously supposed, and that this created a greenhouse effect. Such proposals have problems of their own, however. Another, more radical approach is to question the assumption that the Sun is billions of years old and is just like any other star.

With further research into past ocean temperatures the problem has got even worse. In October 2006 Francois Robert and Marc Chaussidon published an analysis of ocean palaeo-temperatures based on the silicon isotope composition of chert. As the graph from their paper shows (below), their results agreed closely with the results of a previous study based on oxygen isotope composition.

Three things are worth noting here:

• While the Sun is supposed to have been getting steadily hotter, the Earth was getting cooler.
• During the time when the Sun was at its coolest, ocean temperatures are estimated to have been around 70 degrees – an astonishing result.
• From 3.5 to around 1.8 billion years ago there is no long-term trend of gradually falling temperatures: evidence, perhaps, that calls the length of this interval into question.

Like the faint young sun problem, these high ocean temperatures pose a severe challenge for the standard view. High temperatures destroy organic compounds, especially those that carry genetic information. Only the most specialised prokaryotes are capable of surviving temperatures of 70 degrees, and of course this says nothing about how they might have assembled their complex biological machinery before they got to be prokaryotes.

By contrast, the recolonisation theory of Earth history predicts high temperatures during this interval. The Archaean period, dated 3.8 to 2.5 billion years on the radioisotope timescale, was in reality only a few decades, and represents the time immediately after the cataclysm when the waters receded to reveal new, volcanically formed land. The release of these waters from under the original land counteracted the heat energy released by asteroid impacts. Nonetheless, the oceans were still very warm, and continued to be warm for many years thereafter – well into the Proterozoic period (2.5 to 0.54 billion years ago) – owing to very high rates of ocean crust formation. Wherever marine temperatures were at this level, prokaryotes (archaea and bacteria) were likely to be the only kinds of organism that could have flourished and made a mark on the geological record.

High ocean temperatures would also account for the evidence of very low levels of atmospheric oxygen during the Archaean and early Proterozoic. Most of the evidence comes from marine sediments. Although these show extremely small amounts of oxygen in the surrounding water, the solubility of oxygen decreases as water temperature increases. Such evidence may therefore not be a reliable indicator of oxygen levels in the atmosphere.