Conglomerate Drift Boulders and the Post-Flood Ice Age

What do conglomerate boulders in the drift show us about the post-flood Ice Age theory? Creationist writers at ICR, CMI, CRS, AIG and other organizations say an ice age followed the flood of the Bible. The idea seems to have been introduced by the late Henry Morris and John C. Whitcomb in their book "The Genesis Flood" (1961). The presence of conglomerates in the drift suggests the theory is unsound, as the usual interpretation of these rocks involves assumptions about enormous amounts of time involved in their formation. 

The proposed post-flood ice age is not mentioned in the Bible, and is not supported by ancient traditions or myths, or by historical accounts. The theory incorporates uniformitarian geologic principles that undermine the notion of a rapid post flood ice age that lasted only a few centuries.

The theory also proposes that huge populations of Pleistocene mammals such as mammoth, mastodont, giant beaver, giant elk, cave bear, cave lions, and similar species became extinct, not at the time of the flood, but afterwards, in the brief post-flood ice age. This seems to be a very strange idea. How could all those animal populations have multiplied so rapidly from the few survivors of the flood? How were they able to migrate to various continents in such a short time span? Why would they have become extinct during an ice age?

A serious problem for those supporting the idea of a post-flood ice age is the promise of God in Genesis 8:20-22, given to Noah after the flood, that cold and heat, summer and winter, and day and night would not cease. For an ice age to occur, summers would have to effectively cease in certain areas, so that snow could be compacted into ice year after year. The post-flood ice age theory appears to contradict this promise of God to mankind. 

The basic principle on which the glacial theory of Louis Agassiz depends is that rounded pebbles and stones of the drift were rounded by abrasion during transport at the earth's surface, in streams, or under an ice sheet, or by similar processes at the earth's surface. This was one of the basic assumptions in James Hutton's theory of uniformitarianism that was popularized by John Playfair, and Charles Lyell and others. Only a very small fraction of the pebbles and boulders of the drift could be exposed at the surface at one time, so a great age of the earth is implicit in this assumption about the origin of the earth's rounded pebbles and boulders.

Where the drift includes rounded boulders of conglomerate rocks, the problem for the hypothesis of a very short ice age which many creationists support is compounded. There may be several types of these conglomerate boulders present. Assuming all of the rounded pebbles and boulders were rounded during transport, the ones within conglomerate boulders had to be part of some larger rock formation that was eroded, its pieces transported and abraided, so that rounded pebbles were formed and these were incorporated into another rock mass, which was again eroded, and its fragments transported and abraded in the glacial environment so that the conglomerate boulder containing many smaller rounded pebbles also became rounded and smooth.

A rounded conglomerate boulder in the drift gravel with pebbles resembling the surrounding drift pebbles

The boulder at center is a conglomerate boulder in the drift gravel of a kame complex containing rounded and angular pebbles with compositions similar to that of pebbles in the surrounding drift gravel.  These boulders discredit the idea of a rapid post flood ice age as that theory requires the pebbles in the boulder were all rounded by abrasion during transport before being cemented together with the other pebbles in the rock from which the boulder was derived. 

In some congomerate boulders the pebbles resemble those in the surrounding drift, while in others the pebbles appear to have been derived from distant sources. The implication for the idea of a short ice age after the flood is that there is insufficient time for these events to occur since the flood, as the conglomerate pebbles and boulders are distributed throughout the drift.

Perhaps something is wrong with the basic assumption about the stones being rounded by abrasion during transport. If a great flood really occurred, conditions at that period in the past were entirely different to those that exist on the earth's surface today. The writer's in situ disintegration theory of the drift says the pebbles were formed in place by a disintegration process that accompanied unloading due to erosion of overburden by catastrophic currents of a great flood.

The currents were generated by uplift of submerged areas, which displaced the overlying water, spilling it towards surrounding areas. The uplift of the submerged Canadian Shield spilled water towards the southwest and removed an extensive Paleozoic cover, the remnants of which remain in scattered locations on the Shield. These currents excavated the basins of the Great Lakes and formed the escarpments associated with that area, and eroded thousands of other lake basins in the Shield and along its perimeter.

The release of pressure that accompanied the removal of overburden caused disintegration of the freshly exposed surfaces of rock, and the disintegrated material was easily eroded by the catastrophic currents, and redeposited elsewhere. The disintegration process penetrated downwards from the surface, forming layers of drift sand, gravel, and clay. The boulders and pebbles of the drift formed in place, already rounded and smooth, because of concretionary processes. This can also account for the formation of the conglomerate pebbles and boulders in the drift. They too were formed by concretionary processes as the component minerals separated into nodules that became pebbles. The pebbles became incorporated into a larger concretion, that became a boulder when the surrounding matrix disintegrated. 

In the catastrophic environment of a great flood, in which the disintegration process that formed the drift gravels occurred, the currents eroded and redeposited some of the newly formed drift. The disintegration of the rock promoted the erosion of deep basins, canyons, and fjords. The currents of flood waters streamlined the surface of the land over vast areas, forming drumlins and flutings and giant current ripples. As the disintegration penetrated down from the surface the composition of many of the streamlined features was changed, so drumlins and flutings of varying composition occur in the same drumlin fields, having the same form and orientation, although composed of very different materials. Typically in a single drumlin field, some drumlins are composed of bedrock, others are part drift with bedrock cores, and others are entirely composed of drift, which may be stratified. In some regions the disintegration followed joints and penetrated deeper causing valleys and canyons beneath drift with a streamlined upper surface. There is no need for the buried valleys and gorges to have ever been excavated in the disintegration interpretation. The origin of these features and of the drumlins have long been an enigmatic in the glacial theory, but they are easily explained in the environment of a great flood generated by uplift of submerged areas of the earth's crust, and subsequent disintegration forming the drift.

Copyright © 2006 by Douglas E. Cox
The Creation Concept | Controversy About the Glacial Theory