Cape Peninsula sandstones, South Africa, deposited during Noah’s Flood
Published: 26 July 2012 (GMT+10)
Maroon mudstone beds and buff sandstone beds alongside Chapman’s Peak Drive south of Cape Town.
In the steep road cut alongside Chapman’s Peak Drive, south of Cape Town, South Africa, you can see some of the flat-lying beds of sediment that form the 1000-metre (3000-ft) tall mountains along Cape Peninsula. The mudstone has a distinctive maroon colour while the coarser sandstone is buff. The road runs just above the contact between the sandstone and the underlying granite.
Geologists have called these sediments the Graafwater Formation, which is around 70 metres (200 ft) thick along Chapman’s Drive.1 Above it sits another 550 metres (1800 feet) of sedimentary strata, the Peninsula Formation, which lacks the distinctive maroon mudstone layers.2 The Peninsula Formation forms the impressive cliff faces prominent in Table Mountain and the escarpments above Chapman’s Peak Road.2
There are many features of these sandstone deposits on the peninsula that point to large-scale, rapid deposition
There are many features of these sandstone deposits on the peninsula that point to large-scale, rapid deposition, as you would expect during Noah’s global Flood.
- The sediments cover a large geographical area. McCarthy and Rubidge have a geologic map that shows the Table Mountain Group extending beyond Port Elizabeth, 700 km (400 miles) to the east, and almost as far as Vanrhynsdorp, 300 km (200 miles) to the north.3 This points to a geologic process that covered a very large area, as would be expected from Noah’s Flood.
- The sandstone beds are “amazingly uniform”.2 This feature can be seen in the above image of the road cut, but also from a distance when you look at the escarpments in the area, such as the escarpment of Table Mountain or of the Twelve Apostles. Once again, this points to an energetic geologic process that covered a large area.
- The sandstone beds are frequently quite thick, some as thick as 6 metres (20 feet).4 This points to a large water flow with abundant sediment, again as would be expected from the Flood catastrophe.
- The continuous nature of the sedimentation indicates continually rising sea level. There is no evidence of erosion or a break in deposition at the contact between the two formations, so geologists believe that the sediments represent a process of continuous deposition.5
- Sedimentary structures indicating flowing water are common, including large trough and tabular cross bedding.6
- Abundant wave and ripple marks, again indicating flowing water.6
- The sedimentary beds show evidence of slumping, including load casts.6 Imagine how a billiard ball placed on a layer of soft mud would sink into the mud. When sand is deposited onto soft sediment, blobs of sand will sink into the underling mud forming ‘load casts’. These features indicate deposition so rapid that the sediments are still uncompacted and loose.
- Well rounded quartz pebbles up to 70 mm (3 inches) in diameter are distributed through the sandstone, sometimes forming thin lenses of pebble conglomerate.6 These stones give an idea of the water flow needed to carry them along.
Mainstream geologists don’t connect this evidence for large-scale watery deposition with Noah’s Flood. Often they do not appreciate the catastrophic implications of the evidence they are documenting. That is because they have eliminated any thought from their minds that the Flood actually occurred. The Flood does not form part of their interpretive process and this is a major blind spot in their thinking.
Mainstream geologists don’t connect this evidence for large-scale watery deposition with Noah’s Flood.
Instead, they try to explain the evidence in terms of geological processes operating at the present time: slow, gradual, limited in scale and energy. Part of their interpretive process is to match the sediments to a modern depositional environment but, as you can imagine, the match is problematical. In the case of these Table Mountain sediments, various opinions have been put forward7 but the sediments do not seem to comfortably match any environments that exist on the earth today.
One suggestion is that the sediments were deposited partly in a river delta and partly in the shallow ocean. The Graafwater Formation supposedly was in a sheltered tidal setting with large areas of still water (presumably to account for the mudstone8). The Peninsula Formation was deposited in a high energy coastal setting with sandy beaches and bars, to explain the abundant, well sorted sand.7
However, there are many features listed above that this environment does not explain, especially their large geographical extent and the evidence for flowing water and rapid sedimentation. More recently, geologists have suggested a major braided river system flowing over a wide continental plain.1 Today, braided rivers carry abundant sediment and form a wide, flat, gravelly river channels. However, there are many features of the sediments that this environment does not explain, including the thickness of the sediment pile.
Noah’s Flood involved flowing water, and that meant landscape erosion and sedimentary deposition. It covered huge areas of the earth as sea level was rising with respect to the continents. It was an ongoing process that took some five months until the entire earth was inundated (Genesis 7:24). It took a further seven months for the waters to recede from the continents into the oceans (Genesis 8:14–16). The sedimentary rocks forming the Table Mountain Group in South Africa were deposited partway through the first ‘half’ of the Flood as the floodwaters were rising. The evidence is graphic.
Problems with Flood interpretation
There are always questions that flow out of geological interpretations, whether that interpretation is from a long-age uniformitarian perspective or a biblical one. One question that arises when we assign these sediments to rapid Flood deposition involves features called ‘trace fossils’, features that in this case have been interpreted as burrows.9 If the entire Table Mountain Group was laid down during the Flood, then how would there be enough time for organisms to make such burrows within some layers?
However, the ‘burrows’ are sparse and the beds are still clear, crisp and distinct. Depositional features, such as cross bedding, are still very well preserved. This indicates that there was not much time elapsed after each bed was deposited before the next was emplaced upon it. If there had been a long time we would expect the beds to be colonized by organisms and the depositional structures would have been obliterated as they burrowed in the sediments. This is called bioturbation. So, if these features are indeed burrows, they could be escape burrows for organisms that had been quickly buried in the sediment.But they may not be burrows. When these sorts of problems arise we need to question the standard geological interpretations that are automatically assigned. Rapid deposition introduces other possibilities. It’s feasible that they could be features formed abiotically as the sediments were deposited. They could be dewatering tubes on account of the beds being deposited rapidly and needing to release the trapped water as the sediment settled. Or they could be small lenses of a different material, or soft sediment deformation. The fact that they are a different colour further suggests they involved preferential post-depositional staining by iron-rich, mineral-laden pore water.
References and notes
- Compton, J.S., The Rocks and Mountains of Cape Town, Double Storey Books, p.58, 2004. Return to text.
- Compton, ref. 1, p. 60. Return to text.
- McCarthy, T. and Rubidge, B., The Story of Earth and Life: A Southern African Perspective, Struik Nature, Cape Town, p. 194, 2005. John Compton, ref. 1, has a geologic map on pp. 110–111 that also shows the geographical extent of the Peninsula Formation but his map does not extend as far as Port Elizabeth. Compton’s map on p. 17 shows the geographical extent of the Cape Supergroup which compares well with McCarthy & Rubidge’s. Return to text.
- Theron, J.N., Gresse, P.G., Siegfried, H.P. and Rogers, J., The Geology of the Cape Town Area, Department of Mineral and Energy Affairs, Republic of South Africa, p. 27, 1992. Return to text.
- Compton, ref. 1, p. 61. Return to text.
- Theron, et al., ref. 4, p. 29. Return to text.
- Theron, et al., ref. 4, p. 35. Return to text.
- It was long thought that mudstone required a long period of time in a still-water environment in order for the fine particles of mud to settle. However, recent laboratory experiments have shown that mud can deposit from flowing water (See Walker, T., Mud experiments overturn long-held geological beliefs, Journal of Creation 22(2):14–15, 2008.) Return to text.
- Examples of interpreted ‘burrows’ can be found at Mervine, E., Chapman’s Peak Drive, South Africa, May 2011. Chapman’s Peak Nonconformity; http://georneys.blogspot.com/2011/06/chapmans-peak-nonconformity.html. Toward the bottom of the post are a number of photos of filled in burrows, or ‘trace fossils’. Return to text.