Archaeological Discoveries Deep in the Money Pit

By John Wonnacott and Les MacPhie

Part 2 – Interpretation of Findings

1. Introduction

            Important archaeological discoveries were made after the Becker drilling program described in Part 1 was completed in 1967. Drilling programs by Warnock Hersey in 1969 and Golder Associates in 1970 also found evidence of original work at depth in the area of the Money Pit as summarized in Section 2 below.

            So three different drilling programs, with different crews and different equipment, all found intriguing artifacts close to the original Money Pit at depths greater than the “normal” bedrock surface! What is the real significance of these findings? What can we infer from the hard evidence brought to the surface by the drills some 45 to 50 years ago and what is the most probable reality that lies deep underground? In Part 1 of this article, the authors presented the raw data obtained from the Becker program of 1967. Here in Part 2 we give you the best engineering analysis we can think of, plus our best assessment of what the Depositors actually built at the bottom of the Money Pit. Keep in mind that this discussion relates mainly to the archaeological features at about 190 to 200 feet depth and does not consider other interesting findings higher up. Also we have not ventured into the controversial topic of the various theories which have been put forward to explain the “who” and “what” and “when” of the Oak Island Mystery.

2. Additional Discoveries after the Becker Drilling Program

            In 1969 Tobias and Blankenship engaged Warnock Hersey to drill a series of holes. Their report (Warnock Hersey, 1969) indicates that Hole W9 encountered wood chips and highly plastic clay from a depth of 192 to 197.51 feet. From 197.5 to 198 feet, clay and a 2 inch thick layer of “red, silty brick-like material” was recovered. Also from 200 to 206 feet, a possible cavity was reported and the drilling return water from this zone was a different color and had a very stagnant odor.

            Warnock Hersey Hole W8 (put down at the same location as Becker Hole B24) experienced significant lateral drift to the north based on an accurate down-hole survey in 2015. There was little resistance to drilling from 168 to 200.5 feet and limited sample recovery indicated the presence of loose silty sand. Blankenship (1969) reported that the hole encountered clay from about 178 feet to 204 feet. Our interpretation is that the hole ended at 200.5 feet inclined depth which is equivalent to 199.8 feet vertical depth for the measured lateral drift of 17 feet to the north (depth rounded to 200 feet). The important implication of this hole is that the top and bottom locations are accurately known and thus it represents a reliable point to identify the configuration of the Deep Rock area at 200 feet depth.

            In 1970 Golder Associates were engaged to conduct a subsurface investigation including Borehole G103 which was drilled through the bottom of the old Hedden shaft. Based on pollen count analysis (Ritchie, 1970) of soil samples recovered from over 190 feet depth (Sample 27 at 194 feet depth and Sample 30 at 199 feet depth) this hole contained recent soil from the surface in comparison to pollen count analysis identifying ancient glacial soil (embedded in the weathered anhydrite) at an equivalent depth in Hole G102 located 50 feet to the south of G103. Also Hole G103 encountered a zone of very loose soil from 184.5 to 194 feet depth underlying about 30 feet of sound bedrock.

           For convenient reference the summary table of archaeological findings included in Part 1 is reproduced below and the additional archaeological findings are included.

3. Location of Key Historical Shafts and Archaeological Boreholes in the Money Pit Area

There have been so many holes drilled since the first Searchers started investigating, that if all the boreholes close to the Money Pit were plotted, the result would be such a cluttered drawing that nothing very useful could be done with it. So Figure 7 shows only key historical shafts and boreholes with archeological findings in the area around the Money Pit (note that figure numbering continues from Part 1).

The first thing that needs to be said, is that we are confident that the Hedden, 1897 Chappel and 1931 Chappel shafts shown on Figure 7 are correct with reference to each other, and their orientation with respect to True North is correct2. The locations of the Becker, Warnock Hersey and Golder holes with respect to each other are considered to be accurate. It is possible that the relative locations of the shafts on the one hand and the boreholes on the other hand may not be correct with the shafts possibly being several feet further south with respect to the boreholes. However, our best assessment is that the shaft and hole locations shown on Figure 7 are correct and this is the configuration used for interpretation of the archaeological findings.

4. Lateral Drift of Boreholes

We mentioned in Part 1 of this article, that all boreholes are subject to lateral drift – but unfortunately (except for Hole W8) none of the holes that found archeological artifacts were measured for this possible problem3. The many possibilities for the alignment of adjacent holes make it difficult to interpret the configuration of archaeological features. To illustrate this point, Figure 8 provides a number of possible variations of adjacent holes which are six feet apart and vertical or which have 10 feet of lateral drift at a depth of 200 feet. As discussed in Part 1, it is considered that 10 feet of lateral drift at 200 feet depth is likely in the upper range of values, although 10 feet is certainly not the maximum lateral drift possible.

5. Convention for Reporting Depths in Boreholes and Shafts

After the massive excavations by Robert Dunfield in the area of the Money Pit in 1965/66 (Dunfield, 1966), the ground surface was lower by about 10 feet in comparison to the “original ground surface.” Therefore, the Becker, Warnock Hersey and Golder drilling programs were carried out from this new ground surface which is referred to as the “existing ground surface.” However, depths in the Chappell and Hedden shafts are with reference to the original ground surface whereas depths in the Becker, Warnock Hersey and Golder boreholes are with reference to the existing ground surface. The convention adopted for this article is to refer depths to existing ground surface. Therefore depths in the historical records related to the two Chappell shafts and the Hedden shaft have been reduced by 10 feet.

Figure 9 is a photo of the Money Pit area taken about 1967/68 after the Dunfield excavation was backfilled and after the site was graded. The Hedden shaft is visible but the 1931 Chappell shaft, which collapsed during the Dunfield excavation, is completely buried. This photo illustrates site conditions after the Becker drilling program but before the Warnock Hersey and Golder drilling programs. The site conditions illustrated in the photo indicate that depths below existing ground level reported in boreholes are with reference to a datum surface which is reasonably level but which may vary by several feet between widely spaced holes.

Figure 9: Photo of Hedden Shaft Looking West toward Swamp - circa 1967/68

6. Discussion of Main Archaeological Discoveries

In view of the potential for complicated underground configurations of adjacent holes, the only rational approach for discussion of main archaeological discoveries is to start out with the assumption that each borehole was drilled in a straight line at the intended vertical or inclined orientation, keeping in mind that each hole could have wandered off-line as illustrated in Figure 8. There are at least four main discoveries that can be identified from a first examination of the archeological data:

Wood of modern age (versus glacial age) was found below bedrock in Hole B24, which is highly indicative of human activity.
Very stagnant-smelling water was found below bedrock, which indicates rotting organic matter, and this is considered to indicate human activity.
The depth to bedrock in the general area of the Money Pit is between 145 and 160 feet, however, there is a cluster of holes where bedrock is not found until about 200 feet. We refer to this unusual feature as the Deep Rock area.
Most of the Deep Rock holes had a thick layer of puddled clay just before the bottom of the hole.

            We think these discoveries are linked logically, as we will explain a bit later – but first let’s discuss each of these in more detail.

            There are only two ways that we can think of, to explain how modern wood could end up beneath a significant depth of bedrock, which itself is covered by about 160 feet of glacial till. The first scenario would involve development of a large natural cavity in the bedrock and then, well after the last glaciation, development of a sinkhole by “rat holing” from the cavity up through the thick glacial till layer to the surface. This event would then have to be followed by transfer of surface wood to the bottom of the sinkhole with lateral transfer of the wood into the cavity so it is overlain by some 30 to 40 feet of bedrock. We believe this first scenario to be practically impossible, particularly since there is no evidence of massive sinkholes on the Island. The second scenario is that Oak Island Depositors dug a shaft vertically down through 160 feet of glacial till and hit bedrock consisting of weak, weathered anhydrite. As the weathered anhydrite would have been structurally weak, the Depositors continued excavating vertically into the bedrock until they were in sound rock, and then they excavated one or more lateral chambers. If the Depositors were concerned about stability, they would have shored the roof of their chamber(s) with wood that was thick enough to be structurally competent.

           The condition of the weathered anhydrite during the Depositors’ work was completely different from present day conditions. Initially any significant fractures in the weathered anhydrite would be completely filled with low permeability soil thus allowing excavation with only limited and manageable water inflow. In its present condition, the weathered anhydrite is highly pervious due to removal of soil from fractures during long intervals of Searchers’ pumping over the years.

            Samples of the wood found below the bedrock surface in Hole B24 were radio carbon dated and an age of about 400 years was obtained. We now know that radio carbon dating for samples less than about 500 years old is not very reliable4. However, the results are positively definitive in that the wood had to come from a tree which lived no more than about 800 years ago and thus well after the last ice age. So our inescapable conclusion is that the wood found in these holes is of archeological interest and it was placed in chambers created by whoever dug the original Money Pit.

            We think the smell of stagnant water from below bedrock comes from submerged organic matter that has decomposed in a low dissolved-oxygen environment. The same argument that concludes that wood found at this depth must have been placed as a result of human activity, strongly suggests that whatever organic matter caused the stagnant smell, must have originally been placed in the local area by human activity. It is interesting to note that the drilling wash water return (when drilling below the bedrock surface) did not generally have a stagnant smell – the odor was only reported in connection with several subterranean cavities. So all the deep groundwater does not have a stagnant smell, it only occurs in a few deep cavities in the bedrock. We consider that where very stagnant water has been found in cavities or chambers below the bedrock surface, those locations are of archeological significance.

            Enough boreholes have been drilled in the general area of the Money Pit that we know the bedrock surface does not naturally vary by more than 10 or 15 feet in elevation except at the Deep Rock area. So either the Deep Rock area is a natural depression in the bedrock surface or it is a man-made feature. We really can’t be absolutely sure without excavating and examining the area, but drilling records indicate that the sides of the Deep Rock area seem to be about vertical. Most natural bedrock depressions have sloping sides. We also observe that sound anhydrite bedrock occurs below the bottom of the Deep Rock area, whereas the top of anhydrite bedrock is weathered everywhere in the area, other than at the Deep Rock area – and this suggests that the Deep Rock area has not has enough time to begin to show signs of weathering. So it appears that the Deep Rock zone was excavated vertically through 35 to 50 feet of weathered anhydrite. Everything we know about the Deep Rock area is consistent with the concept that it is man-made. We have selected a diameter of 16 feet for the Deep Rock area and realize that the diameter could be somewhat larger (if some of the boreholes were subject to lateral drift).

            We discussed the characteristics of “puddled clay” in Part 1 of this article. Puddled clay was used for centuries to seal areas from water intrusion. It is very interesting that puddled clay was found in the Deep Rock and Money Pit areas and nowhere else in the immediate area. Since we believe these features are man-made, we consider that the puddled clay was placed by Depositors as part of their underground construction.

           We have concluded that the wood found below bedrock was part of a roof shoring system for structural support of chambers excavated in the rock. We also believe that the Depositors were concerned about water seeping into their chamber(s) from above, particularly while they were working, so they would have sealed the roof with clay after shoring the roof, and they would have needed a second layer of wood to hold the clay in place. This accounts for the “wood/clay/wood/ 6 foot space” sequence found in Hole B24. Perhaps the side walls of the chambers are also lined with clay, but we have no data to support or contradict this notion. Either way, seepage water would have been directed around the chamber(s), collecting on the chamber floor, where side drains could have conducted it to sumps where it would have been pumped, or lifted in containers, to the surface. When the Depositors had finished building their chambers and depositing their treasure, we believe that they would have installed a timber bulkhead at the entrance of each chamber and then filled the bottom of the Deep Rock area with puddled clay. Based on current engineering principles, the reason for using puddled clay in this fashion is not readily evident to us. It is likely that the Depositors had reasons for using puddled clay which are not consistent with modern practice in underground engineering.

7. Discussion of the Configuration of the Underground Workings

          Because wood was found at several quite widely-spaced locations, we conclude that there is more than one lateral chamber in the bedrock. For example, Boreholes B25 and B33 are 24 feet apart, and a single underground chamber 24 feet wide would require massive geotechnical supports – so this suggests that B25 and B33 encountered separate chambers extending out from the base of the Deep Rock area. However, there is an unlikely scenario where these two holes each drifted 10 feet toward each other in which case the holes would be 4 feet apart at 200 feet depth and thus could be in the same chamber. We consider that this scenario is highly improbable.

          We don’t know how many chambers there are, but we have settled on three chambers as being a likely configuration and we have numbered them Chambers 1, 2 and 3. Chamber 1 is in the area of Holes B24, B33 and W9, all located to the south of the Deep Rock area and all having archaeological features at about the same depth. Chamber 2 is associated with Hole B25 where an iron plate was encountered at 198 feet depth. Chamber 3 is associated with Borehole G103 where recent soil from the surface was encountered. It is noted that, since G103 was drilled through the bottom of the 115-foot deep Hedden shaft, there would not have been much lateral drift in this hole. It is of interest to note that G 103 is about 24 feet from both B25 and B33 and that B25 and B33 are about 24 feet apart.

         There is an interesting demonstration of lateral drift and how elusive the chambers are when trying to intersect them with a borehole. Warnock Hersey Hole W5 (not shown on Figure 7) was put down half way between Holes B24 and B33, both of which were assumed to intersect Chamber 1, with the objective of verifying the continuity of the chamber. However no indication of a chamber was found in this hole which extended to a depth of 210 feet. Also Warnock Hersey Hole W7 (not shown on Figure 7) was put down 3 feet east/northeast of Hole W5. No archaeological features were found in this hole which extended to a depth of 218 feet. However, both Holes W5 and W7 encountered significant soil inclusions in the weathered anhydrite.

          We think the Depositors tried to construct chambers with a 6 foot roof height, as that would have been a convenient height for mining – and where the chambers were measured to be 7 feet high, those would be places where more of the roof came down than intended, during the mining. We don’t know the length of the chambers but Holes B 33, B25 and G103 at Chambers 1, 2 and 3 respectively are only some 5 to 7 feet (at surface) beyond the inferred limits of the Deep rock area. We have assumed for illustration purposes that the chambers extend about 20 feet beyond the limit of the Deep rock area. Figure 10 shows a plan view of the chambers, Figure 11 shows Section A-A through Chamber 1, Figure 12 shows Section B-B through Chambers 2 and 3 and Figure 13 illustrates our concept of a typical cross section through a chamber. Figure 12 shows a projection of the original Money Pit to Section A-A and the implications of this configuration are discussed in Section 8.

Figure 13: Authors’ Concept of a Typical Cross Section through a Chamber

As explained in the preceding text, the presence of puddled clay, and the use of clay between layers of wood in the shoring for chamber roofs, indicates that the Depositors had concerns about ground water seeping downward into their workings. During construction of the underground chambers, this seepage water would have been an issue for the Depositors to deal with, and the conventional way to manage seepage water like this, is to excavate one or more sumps at low points in the underground workings, and install some form of pumping at those places. We think the ½ inch iron plate that was found in Hole B25 may possibly have been used to cover a sump hole which would have been excavated in the floor of one of the chambers. The plate would have been pulled back for pumping, and replaced when people needed to walk across the chamber floor.
So in our opinion, all of the archeological features found below the bedrock surface are consistent with construction of deep chambers which very likely would have been excavated as storage places for objects of great value. In other words, we think the archeological discoveries mentioned in this article strongly support the idea that the Money Pit was constructed to store some form of treasure or highly valued artifacts.

8. A Remaining Problem

After developing our concept for the configuration of chambers at 200 feet depth, we are left with one very puzzling and troublesome observation. The center of the Deep Rock area is about 18 feet away (to the southeast) from the center of the original Money Pit. Most previous publications (including Harris and MacPhie, 2013 and Triton Alliance, 1988) assumed that the original Money Pit was directly over the Deep Rock area. Our best estimate of where the Money Pit was located is shown on Figure 14. The supporting evidence for the correct Money Pit location is discussed below.

          The correct position for the original Money Pit has always been a subject of some uncertainty. In the first place, we have no record of any reliable survey having been done, which tied the original Money Pit to other still-existing reference points. During the 1800’s many attempts were made to excavate at the Money Pit, and when these initial attempts to recover treasure were flooded out by water rapidly rising in the original workings, a series of new shafts were dug near the original Money Pit. These new shafts eventually either collapsed or were later backfilled so that by the 1930’s no evidence of the original Money Pit was visible at original ground surface. One good reference to the position of the original Money Pit is based on the work of William Chappel5 in 1897. In this regard, his records are the oldest reliable accounts on the subject, and thus should contain the fewest historical inaccuracies. M. R. Chappell, in his manuscript (Chappell M. R., 1973, Page 24) recorded information on the location of the 1897 William Chappell shaft as follows: “At this time the Money Pit which was not cribbed and therefore not too safe was used as the pumping pit, work and drilling being done in a new timbered shaft about five foot by eight foot south of and close to the Money Pit.” It is noted on Figure 14 that the perimeter of the Money Pit is only 4 feet from the 1897 shaft and that the shaft is positioned at a right angle to the Money Pit perimeter as would be expected. Since constructing a shaft would require a lot of effort and a sizeable financial outlay, we assume William Chappell consulted old records and spoke to older eye-witnesses to be as sure as possible that his new shaft was located close to the old Money Pit. Chappell probably had direct access to people who worked on Oak Island in the 1850’s, and those early Searchers almost certainly knew where the original Money Pit had been located.

            Additional evidence of the original Money Pit location was recorded during the work by Dunfield (1965) where he reported that “At 8:00 am, November 4, 1965, we reached a depth of 22 feet and we have observed 1/2 to 2/3 of the original money pit well defined immediately north of the Chappell Shaft.”   M. R. Chappell also reported (Chappell M. R., 1973, Page 82) on the position of the original Money Pit exposed by Dunfield as follows: “the thirteen foot circular uncribbed shaft appeared about fifteen feet north of the Chappell shaft and ten feet west of the north end of Hedden shaft.”   The dimensioned position reported by M. R. Chappell was used to plot the location of the original Money Pit shown on Figure 14 with the dimensions assumed to be to the center of the Money Pit. It is clear that this location is also consistent with the other two descriptive locations of the Money Pit.

            Our thinking of the way the Money Pit was constructed, is that the Depositors dug a vertical shaft through the glacial till, and when they encountered the anhydrite bedrock, with weathered zones and soil-filled cavities near the surface, they just kept excavating through the rock until they got to sound rock conditions, and at that depth they started excavating lateral chambers. We always thought that the Deep Rock area was the downward extension of the Money Pit – so how could the bottom of the Money Pit be so far away laterally, from the Deep Rock area?

            We have been puzzling over this problem for the past few weeks. One obvious answer to the problem could be that there was a series of surveying or recording errors in the positions of the boreholes or the Hedden/Chappel shafts. There indeed were several errors made in some of the old surveys, but we just cannot find any errors that are anywhere close to being large enough to explain away the problem.

            Another possibility is that the boreholes that ran into the Deep Rock area all drifted laterally to the north/northwest. Any one hole could have deviated by 18 feet, but we just cannot accept that all the holes that hit Deep Rock had the maximum lateral drift, all in the same direction!! Theoretically it would be possible, but the probability of that happening is astronomically tiny.

            We are now mulling over the possibility that there were two vertical components to the Money Pit – another possible device, something never considered by Searchers until now – created by the Depositors to throw off future Searchers, if they ever dug as deep as the bedrock surface. Perhaps the original Money Pit was dug exactly where we believe it was dug, down to bedrock, and then perhaps the Depositors built a short lateral tunnel with temporary shoring that they would have removed after depositing their treasure, and from there they excavated vertically into the bedrock, creating the Deep Rock area and the underground chambers in rock. There are other possible scenarios for connecting the original Money Pit and the Deep Rock area. However, this issue has not been addressed in detail since it is beyond the scope of this Part 2 article.

            We know the idea of having an offset shaft in the bedrock, as described above, may not be readily accepted. This is why we have taken so long to write the second part of this article – we have been struggling to find a solution - but we just cannot find another explanation for the 18 foot discrepancy between the Money pit location and the Deep Rock area location. So we are opening up this point for discussion by thoughtful Readers. We have gone through a lot of historical records and surveys that confirm the location of the shafts and boreholes, and we can provide the details if there is enough technical interest.

         We are asking Readers to suggest alternative solutions to this remaining problem. There can be little doubt that the archeological discoveries of the Becker, Warnock Hersey and Golder drilling programs demonstrate that there are man-made workings deep below the normal bedrock level at the Money Pit. So what exactly did the Depositors build?? There is a way to find out.

9. Large Diameter Shaft to 200 Feet Depth

            The concept of constructing a large diameter shaft to 200 feet depth to explore the chambers at that depth was considered by Triton Alliance in 1988. The project is described in their promotional document (Triton Alliance, 1988) but the project did not proceed due to lack of financing. However, this approach would give detailed information on the configuration of the chambers at 200 feet depth, would determine the contents (if any) of the chambers and would in all likelihood solve the Oak Island mystery. In addition, issues related to chests at 90 feet and a vault (with parchment?) at 140 feet should be resolved, because those probable artifacts would be within the area to be excavated. Excavation within a large diameter shaft would have to be carried out with particular care to preserve the archaeological heritage of the Money Pit, the Deep Rock area and the related chambers, as required by current legislation.

            Several technologies for design and construction of such a shaft, even in the difficult ground conditions at the Money Pit, are readily available and there is successful precedent for the use of such technologies. The authors have participated as external advisors in three different conceptual designs for a large diameter shaft at the Money Pit as part of a Design Project program for fourth year engineering students at McGill University, Montreal, Quebec. The reports on these Design Projects (McGill University 2006, 2008 and 2014) include only conceptual designs and order of magnitude cost estimates. The technologies considered are ground freezing (perimeter freeze ring), secant piles (continuous ring of interconnected concrete piles) and grouting (jet grouting and conventional pressure grouting). We consider the ground freezing design to be the preferred approach.

            One of the interesting questions for such a design is to select the diameter of the shaft. This depends to a large extent on the actual length of the chambers. Assuming that the chambers are 20 feet long and allowing a distance of 7 feet between the end of the chambers and the wall of a shaft centered on the Deep Rock area, the diameter of the shaft should be 70 feet. The plan limits of a 70 foot diameter shaft are shown on Figure 15. It is noted that there is a clearance of about 10 feet between the wall of the shaft and the closest edge of the original Money Pit. In final deliberations for shaft design, consideration could be given to a larger diameter or to moving the shaft some 5 feet northwest (from that shown on Figure 15) so that it is centered more on the combined Money Pit and Deep Rock areas. If additional drilling more accurately identifies the configuration of the chambers, consideration could also be given to constructing a shaft with a diameter smaller than 70 feet. On the other hand, Triton Alliance proposed an 80 foot diameter shaft to 200 feet. Figure 16 shows a schematic cross section of the 80 foot diameter shaft proposed by Triton Alliance in 1988.

Figure 16: Schematic Section of 80 Foot Diameter Shaft Proposed by Triton Alliance in 1988

We think that a large diameter shaft to 200 feet would not only reveal many of the secrets of Oak Island’s Money Pit, its construction would generate tremendous world-wide interest. Imagine a weekly television show that presented all the artifacts, old Searcher’s structures and construction issues encountered since the last episode. Until someone builds such a shaft, the idea will give us all something to daydream about!

10. Conclusion

We hope through Parts 1 and 2 of this article, that we have demonstrated strong evidence that there are man-made structures deep in the Money Pit area. These structures are far deeper than any Searcher has ever been known to have explored. We can understand an overall construction sequence in which the deep underground workings were first constructed, and then the flood tunnel (possibly more than one) was built to prevent Searchers from recovering whatever was placed in the expected underground chambers. But the possibility that some unknown Searcher could have overcome the man-made water problems and other technical challenges, dug down to 200 feet and created these underground workings – and kept all of their efforts a secret to this day – is beyond what we are prepared to believe. So we conclude that the archeological artifacts buried deep in the Money Pit area are the work of whoever first created the Money Pit. We believe there is original construction down there, and very possibly treasure of great value.

Footnotes:

The Warnock Hersey drilling program consisted of casing the hole when they were in overburden, coring with a diamond bit and core barrel when they were in rock, and sometimes drilling ahead with a tricone bit when the drilling conditions became too difficult for the core barrel to advance. So they were not able to obtain a continuous record of samples in some places. The zone from 192 to 200 feet in Hole W9 was one of those places. The drilling notes for this hole indicate that the drillers thought that perhaps the drill was on wood at a depth of 192 feet in this zone, and that is what impeded the core barrel. We do not know precisely where in this zone the wood was encountered, but we know that wood chips came back in the wash water in this zone, and the drillers thought they had drilled through at least 4 feet of solid wood.The location and true north orientation of the 1931 Chappell shaft and the 1937 Hedden shaft were defined by the Roper survey in 1937.
Borehole W8 (one of the Warnock Hersey holes) had a lateral drift measurement of about 17 feet to the north. There is no reason to assume this hole had the greatest lateral drift of any borehole, so we must assume that at least some other holes had lateral drifts of 17 feet or more.
Because new research has found that the atmospheric concentration of C14 was not constant throughout the past 500 years, so when the C14 concentration in the sample being tested is measured, and the known decay rate of radioactive C14 is used to calculate the age of the sample, multiple ages result because there are multiple possibilities for the initial concentration of C14.William Chappell was the father of Mel R. Chappell, who constructed a new “Chappell Shaft” in 1931. When M. R. Chappell was laying out the position for his shaft, William Chappell was on the site to help his son. During the early excavation of the 1931 Chappell Shaft, William Chappell was on site and was able to identify parts of the old 1897 shaft that the new excavation was uncovering. Therefore the position of the two Chappel shafts with respect to each other is quite precise.
The depths of 150 feet and 161 feet are 160 feet and 171 feet respectively in the Chappell affidavit.

References

Blankenship, Dan, 1969. Memorandum dated November 29, 1969. (This memorandum gives descriptive results of Warnock Hersey Boreholes W8, W9 and W10.)

Chappell, William, 1929. Affidavit Made in Connection with the Drilling Done in 1897, October 25, 1929. (Notarized by C. Guy Black)

Chappell, M. R., 1973. The True Story of Oak Island. Draft manuscript of events to 1965 transmitted to Dan Blankenship by letter dated September 20, 1973. (83 pages and four plans)

Dunfield, Robert R., 1965. Oak Island Project, Report dated November 4, 1965 (1 page).

Golder Associates, 1971. Subsurface Investigation, The Oak Island Exploration, Oak Island, Nova Scotia. Draft Report No. 69126 to Triton Alliance Ltd., Montreal, Quebec, April 28, 1971.

Harris, Graham and MacPhie, Les, 2013. Oak Island and Its Lost Treasure, Third Edition. Formac Publishing Company Limited, Halifax, Nova Scotia, 2013.

MacPhie, Les, 2008. The Money Pit, Oak Island, Nova Scotia, Summary of Geotechnical and Archaeological Conditions and the 1967 Becker Drilling Results. Technical Report, January 2008.

McGill University, 2006. Design of a Deep Excavation Using Ground Freezing Technology, Oak Island, Nova Scotia. Report on Design Project by Fourth Year McGill Engineering Students (Cheehan Leung, Shoshanna Saxe and J. Ryan Thé).
McGill University, 2008. Design of a Deep Shaft to Explore Underground Workings and Recover Potential Treasure on Oak Island, Nova Scotia. Report on Design Project by Fourth Year McGill Engineering Students (Chritopher Ong Tone, Nathan Ramsey, Behnam Shayegan and Robert Wolofsky).

McGill University, 2014. Feasibility Study of a Deep Excavation to Preserve the Archaeological Heritage of Oak Island, Nova Scotia. Report on Design Project by Fourth Year McGill Engineering Students (Mariam Abdul Ghani, Claire Meloche, Nabil Nassor, Rebecca Stanzeleit and Ming Jia [Peter] Wang).

Ritchie, J.C., 1970. Report on Palynological Analyses of Four (4) Samples from The Oak Island Exploration. Dalhousie University, Halifax, Nova Scotia, May 1970.

Triton Alliance Ltd/Ltée, 1988. The Oak Island Exploration, Summary of Operations, Field Findings and Operational Plans.
Warnock Hersey International Limited, 1969. Soils Investigation, Oak Island, Nova Scotia. Report No. 530-110 to Carr & Donald & Associates, Toronto, Ontario, July 31, 1969.

(Note: The initial report was followed by Warnock Heresy Letter dated August 27, 1969 transmitting the logs for Boreholes W5 and W7 and by Warnock Hersey Letter dated November 5, 1969 transmitting the descriptive results of Boreholes W8, W9 and W10.)

Acknowledgements

We would like to acknowledge Oak Island Tours for providing detailed information on the lateral drift measurements in Hole W8.

Also we wish to acknowledge the excellent work by Mark Sykes in drafting most of the figures for this article.