|Rescued from the|
|Seven of the clean kind|
Flood geology is a "branch" of "creation science", and is most used in young Earth creationism to try and "prove" that the Earth is only 6,000 years old. It assumes that the Biblical Great Flood was an actual historical event and attempts to interpret geology in terms which make it consistent with the flood myth.
Geology is a branch of science that first developed and evolved to its present form throughout the 19th and 20th centuries. Prior to this, the accepted age of the Earth in most of the western world was that of the Ussher chronology - this was due to the dominance of religion and the lack of any real evidence to state otherwise. With the development of radiometric dating, the close examination of fossil records and rock strata, and the increase in technology required to study these features it became very clear that the Earth was, in fact, much, much older. Some of the earliest estimates based on scientific reasoning and evidence put the Earth between 20 and 400 million years old - but even that was too young for geologists and biologists of the time who were getting to grips with both evolution and the ages of rocks. This has nothing to do with "destroying God" as many creationists may claim, it is simply the case that evidence came along and threw out the old theory on the age of the Earth. This is often handwaved by organisations such as Answers in Genesis, which claim that a conclusion is dependent on a "world view"; a secular scientist will look at rock strata and see age, a True Believer will see Noah's flood.
Science doesn't generally return to outdated and disproved ideas. This is because when evidence is sought, it is used to disprove theories (see falsifiability) and so old theories are often incompatible with new evidence. So any old theory that is resurrected invariably appears in a slightly mutated form that must explain the new evidence. As the idea that the Earth was less than 10,000 years old was very much discounted by evidence, flood geology is faced with a remarkably difficult task; it must reconcile an old idea (that the Earth is young and everything is explained by a global flood) with the very evidence that was used to firmly discount it. Flood geology is, therefore, obliged to ignore the majority of geological evidence and misinterpret the rest.
 Specific claims
Advocates of flood geology generally use the flood as an explanation for the existence of the geologic column, and indeed any geological phenomena or feature. It proposes that the age of the Earth as shown by rock strata is only apparently old, an illusion caused by looking at it through a secular worldview. Thus, while a scientist may spend years developing and testing theories through evidence, a flood geologists simply knows that the "flooddidit" - an attitude similar to goddidit as found in other literalist beliefs and religious apologetics. Flooddidit is invoked to explain geological features as different as the Grand Canyon and the Sahara Desert. Naturally, there are numerous inconsistencies with using flooddidit this way, as a global flood should have morphed and shaped rock formations globally the same way. This is not observed, but this is rarely a problem for flooddidit advocates.
Fossils are found in geological strata with older organisms at the bottom and newer organisms at the top. Not by coincidence, this also matches up with evolutionary theories; the less developed organisms are found lower in the rock strata while their descendants are found above. Flood geology often tries to solve this problem by invoking a form of "sorting" during the flood. YEC belief necessitates that all animals found in the fossil record were alive and interacting at the same time - including dinosaurs and people. The fossil sorting is stated to be because smaller, less developed animals counldn't outrun the flood waters so are found buried at the bottom, while the more advanced animals are found at the top because they could outrun the flood waters.
Obviously, the flood geology explanation for fossil sorting is ludicrously at odds with evidence. Firstly it neglects that fossils are sorted by their ability to escape flood waters would mean animals are found in that order in the fossil record. This is not observed to be the case, with animals of different sizes and physical ability being scattered throughout the geological strata - there seems to be no ordering by physical ability. Secondly, such a theory would suggest only a statistical tendency. That is, there is a chance that some animals that would otherwise have been capable of outrunning flood waters would still fall early and drown, while those that wouldn't outrun the waters may have been lucky enough to be in the right place to get a bit further than the rest. In reality, the fossil record shows absolutely no fossils out of order. Organisms never appear in more recent rock than their descendants. Similarly, mass extinction events such as the KT boundary provide very fine lines that cut off the fossil record - this is incompatible with the idea that all rock sediment was laid down only a few thousand years ago in a massive flood.
Erosion is a slow process in conventional geology - unless the rock is soft and the weather particularly severe, but these cases are outlying exceptions. This is all due to the hardness of rock and the fact that we can observe the rate that it erodes under rain now. The flooddidit idea proposes that despite this, all erosion features can be explained by the flood. This applies equally to rock that is eroded to rock that isn't eroded - a proposition that flies in the face of both science and good sense. The high levels of erosion seen in hard rock formations is chalked up to the speed of the flood waters. Indeed, fast water can be quite powerful and water cutting jets can slice through objects with high efficiency. However, the Grand Canyon, for example, isn't a small board of MDF being hit by a precise sub-millimeter wide jet of water traveling at hundreds of miles per hour. Even in a flood of global proportions, the water could not travel fast enough (it can only work under gravity) and the rock is simply not soft enough for it to form in anything less than millions of years.
Secondly, erosion due to the flood is incompatible with rock sedimentation being explained by the flood. A global flood that would explain both sedimentation and massive erosion would cause both processes to occur simultaneously. There should be more sediment put down at a near equal rate to the erosion removing it - therefore features where erosion has revealed the sedimentation layers should not exist. Conventional geology is able to explain that sedimentation occurs first and erosion cuts in afterwards to expose the layers, and also explains more distorted features such as uncomformities - which flood geology is unable explain.
Uniformitarianism is the overarching scientific principle that physical laws are invariant with respect to space and time - or with less technobabble, they don't change. This is a sound principle because it is what is observed and also the simpler explanation given that the laws lack any causal motivation to change. With respect to geology it states that the way we see sendimetary rocks laid down today is the same mechanism that caused them to be laid down a hundred, a thousand, a million or a billion years ago. It states that erosion and weathering is the same. And while it doesn't dismiss the impact of single massive events (from glacial flooding to meteor impacts) generally what is seen today is the result of slow and steady processes rather than massive catastrophic events. Because this assumption invariably leads to a 4.5 billion year old Earth, flood geology says balls to this assumption. Uniformitarianism isn't just an assumption used to generate the billion year age of the Earth, as creationists claim, but is a founding principle of physics; as said before, you need to have a good reason to say the laws of physics change over time, and evidence that they do.
In order to prove a 6,000 year old Earth, flood geology abandons uniformitarianism but doesn't really replace it with anything consistent. Instead, what is normally explained with slow processes and a uniformatarian view is explained with special pleading and flooddidit. This ranges from radioactive decay, which was "somehow" faster during the flood, to continental drift, which must have been practically supersonic during the flood, to magnetic field reversals, which just oscillated wildly during the flood for no other reason than it was the flood. Flood geologists will defend this sort of thing as merely just rejecting an assumption (much in the same way theological presuppositionalism works) but without solid evidence or explanations about how and why these rates arbitrarily changed to give an illusion of a 4.5 billion year old Earth, the creationists are doing nothing except making shit up.
 Radiometric dating
Less commonly but more hilariously, flood geology is invoked as an explanation for the appearance of an old Earth in radiometric dating. This is a specific version of flooddidit and the rejection of uniformitarianism; so the rate of radioactive decay was somehow faster "back then". The hilarious part comes that if such assumptions are taken to their logical conclusion. The decay of radioactive elements (uranium, potassium and thorium) is a slow process taking billions of years, accompanied by the release of heat, and supplies enough energy to keep the Earth's core liquid. Flood geology suggests that most of the decay happened in a short time frame, at least a million times faster. During this time, the natural radiation would be higher than 1 lethal dose per day, and the released heat would be enough to melt the earth completely, if not boil it.
Unfortunately flood geology has never been used to discover any resources of value to man (oil, gas, water, iron, copper, etc.) in the way that secular, old-Earth geology has been able to do. Despite this one company, Zion Oil is attempting to find oil in Israel based on an interpretation a Biblical passage; albeit using conventional secular technologies.