www.Sarsen.org: A review of "Carn Goedog on Mynydd Preseli Was Not the Site of a Bluestone Megalith Quarry" by Brian John

Key Points

This review suggests the paper has logical arguments but may rely on some assumptions, like glacial transport, without strong evidence.
While the paper uses many independent references, though some claims lack specific citations, it relies heavily on self-citation.
The presented evidence leans toward natural processes explaining Carn Goedog's features, but this is debated among researchers.

Introduction to the Paper

The academic paper "Carn Goedog on Mynydd Preseli Was Not the Site of a Bluestone Megalith Quarry" by Brian John, published in April 2025, challenges the idea that Carn Goedog in Wales was a Neolithic quarry for Stonehenge's bluestones. It critiques claims by Parker Pearson et al., suggesting natural processes like glaciation better explain the site's features.

Logical Analysis

The paper presents detailed arguments, questioning the geochemical link between Carn Goedog and Stonehenge's stones and arguing that features like platforms and ditches are natural. However, some arguments, such as dismissing archaeologists' work as biased, may feel more like personal critique than evidence-based reasoning. The claim that glacial transport explains stone movement lacks direct proof, especially given the 200 km distance, which is debated.

Reference Independence

The paper cites over 50 sources, including independent works by Bevins, Ixer, and Parker Pearson, showing engagement with research. However, key claims, like radiocarbon dating not supporting quarrying, lack specific citations, which might weaken its support. While self-citation is present, it's balanced by other studies, suggesting reasonable independence.

Unjustified Assumptions

The author assumes glacial activity moved the stones, but this isn't fully justified, as it's debated whether glaciers could transport large monoliths far. Assuming site features are natural rather than man-made also lacks comparative evidence, leaving room for doubt. These assumptions highlight areas where more data could strengthen the argument.

Detailed Critical Review of the Academic Paper

The academic paper "Carn Goedog on Mynydd Preseli Was Not the Site of a Bluestone Megalith Quarry" by Brian John, published in April 2025, presents a comprehensive critique of the hypothesis that Carn Goedog, a dolerite tor in Pembrokeshire, Wales, was a Neolithic quarry for Stonehenge's bluestones. The author challenges claims by Parker Pearson et al., arguing that natural processes, particularly glacial activity, better explain the observed features.

Background and Summary

The paper argues against the "precise provenancing" of Stonehenge's spotted dolerite to Carn Goedog, highlighting the geochemical heterogeneity of dolerite sills in the area and the limited accessibility of suitable monolith pillars, which are mostly frost-shattered and weathered. It suggests that features identified as quarrying evidence, such as "engineering features" and stone tools, may be natural or unrelated to quarrying, and that radiocarbon dating does not support the hypothesis. The author proposes glacial activity as a likely mechanism for stone transport, concluding that Carn Goedog likely saw intermittent occupation rather than quarrying.

Analysis of Errors of Logic

The paper's logical structure is generally robust, with systematic counterarguments to Parker Pearson et al.’s claims. For instance, it questions the interpretation of features like an "access point" through scree and "recesses in the rock face," suggesting they are natural rather than engineered, supported by observations of frost-shattered blocks and ice-moulded surfaces, which align with geological processes.

However, there are potential logical weaknesses:

Ad Hominem Critiques: The author notes that Parker Pearson et al. published no peer-reviewed papers for several years, which could be seen as an attack on credibility rather than addressing their evidence. This rhetorical approach may undermine the paper’s objectivity.
Assumption of Glacial Transport: The claim that glacial activity explains stone movement is presented without sufficient evidence for long-distance transport (approximately 200 km to Stonehenge). While ice-moulded surfaces are cited, the feasibility of glacial transport for large monoliths is debated, as seen in studies like Scourse (1997, not directly cited but referenced in broader literature), and the paper does not address this controversy, leaving a logical gap.
Lack of Detail on Radiocarbon Dating: The assertion that radiocarbon dating does not support quarrying is mentioned but not elaborated with specific data or references, leaving it logically unsupported and potentially speculative.

These gaps suggest that while the paper raises valid points, some arguments could be strengthened by avoiding personal critiques and providing more evidence for key claims.

Assessment of Independent References

The paper includes an extensive bibliography, with over 50 references covering geological, glaciological, and archaeological studies, indicating broad engagement with the literature:

Strengths: Citations include independent works by Bevins et al. (2014) on geochemical analysis, Patton et al. (2013) on glaciation, and Parker Pearson et al. (2019) on archaeological claims, demonstrating reliance on diverse sources. For example, Bevins et al. (2014) is referenced to discuss geochemical overlaps, and John (1970) supports glacial activity in the region.
Weaknesses: Some key claims lack specific citations. For instance, the statement that radiocarbon dating does not support quarrying is not backed by referenced data, which is a significant omission given its importance. Additionally, while the author cites their own work (e.g., John, 2018; John et al., 2015a), this is balanced by numerous independent sources, suggesting no major lack of independence overall.
Balance of Self-Citation: The author's self-citations, such as John (2024a, 2024b, 2024c), are relevant to the topic but do not dominate, with many references to other researchers like Parker Pearson and Bevins, indicating a reasonable balance.

A table summarizing the distribution of references by author type is provided below:

Author Type	Number of Citations	Examples
Independent Researchers	~45	Bevins et al. (2014), Patton et al. (2013)
Author Self-Citations	~10	John (2018), John et al. (2015a)
Collaborative Works	~5	John, Elis-Gruffydd & Downes (2015a)

This table shows that while self-citation exists, it is not excessive, and the paper engages significantly with independent research.

Evaluation of Unjustified Assumptions

The paper makes several assumptions that may not be fully justified, potentially weakening its argument:

Glacial Transport Assumption: The author assumes that glacier ice was responsible for moving bluestones, citing ice-moulded surfaces and smoothed bedrock as evidence. However, this assumes glaciers could transport large monoliths over long distances, which is debated. For example, studies like Scourse (1997) question the glacial transport hypothesis for Stonehenge bluestones, and the paper does not address this controversy, leaving the assumption unjustified without direct evidence.
Natural Origin of Features: The assumption that features like the "platform" and "ditch" are natural rather than man-made is central to the argument. While the author cites frost-shattered blocks and glacial erosion, they do not provide comparative examples of similar natural formations from non-quarry sites, making this assumption speculative. This is particularly significant given archaeologists’ interpretations of these features as quarrying evidence, as seen in Quarrying of Stonehenge ‘bluestones’ dated to 3000 BC.
Intermittent Occupation Over Quarrying: The suggestion that Carn Goedog saw intermittent occupation rather than quarrying lacks strong archaeological evidence, such as artifacts or structures indicative of habitation. This assumption is not supported by detailed data, potentially undermining the conclusion.

Context from Broader Research

There is a significant body of research supporting the quarrying hypothesis at Carn Goedog. For instance, Megalith quarries for Stonehenge's bluestones (2019) confirms that excavations at Carn Goedog and Craig Rhos-y-felin revealed evidence of quarrying around 3000 BC, contemporaneous with Stonehenge’s construction. Similarly, Carn Goedog is the likely major source of Stonehenge doleritic bluestones (2014) uses geochemical analysis to identify Carn Goedog as the major source, aligning with Parker Pearson et al.’s findings. However, Brian John’s blog post, Stonehenge and the Ice Age: The Carn Goedog bluestone provenancing is unsupported by the evidence, critiques this view, suggesting the stones could be glacial erratics, reflecting ongoing debate. A 2024 article, Research claims Stonehenge bluestones did not come from west Wales, also casts doubt on the origin of some bluestones, indicating the topic remains contentious.

Detailed Findings and Implications

Geochemical Evidence: The author questions "precise provenancing" by noting geochemical heterogeneity and overlaps (e.g., Bevins et al., 2014), which is supported by independent research. However, more detail on why this challenges the quarry hypothesis could enhance clarity, especially given Carn Goedog is the likely major source of Stonehenge doleritic bluestones.
Geomorphological Evidence: Observations of limited suitable pillars and absence of columnar jointing (less than 10% of the outcrop) are compelling, but the natural interpretation of features needs comparative geological data to be fully convincing.
Glacial Evidence: Ice-moulded surfaces and smoothed bedrock are cited, supported by references like John (1970) and Patton et al. (2013), but the paper should address debates on glacial transport feasibility to avoid appearing one-sided, as seen in broader discussions like Stonehenge quarries - Archiwik.
Archaeological Critique: The lack of peer-reviewed evidence from Parker Pearson et al. is a valid point, but the author’s dismissive tone (e.g., "inventions," "bias") could be seen as unprofessional, potentially affecting perceived objectivity, especially when compared to Quarrying Of Stonehenge Bluestones Dated To 3000 BC | University of Southampton.

Recommendations for Improvement

To enhance the paper’s rigour, the author could:

Provide specific references and data for claims like radiocarbon dating not supporting quarrying.
Include comparative studies of natural formations to strengthen the argument that features are not man-made.
Acknowledge and address counterarguments, particularly on glacial transport, to present a balanced view.
Reduce rhetorical language when critiquing other researchers to maintain academic tone.

Conclusion

The paper offers a detailed critique of the quarrying hypothesis at Carn Goedog, supported by geological and geomorphological evidence, with a broad range of references. However, it contains logical gaps (e.g., ad hominem critiques, insufficient evidence for glacial transport), some claims lack specific citations (e.g., radiocarbon dating), and it makes unjustified assumptions (e.g., natural origin of features). These weaknesses suggest areas for improvement, particularly in addressing controversies and providing more robust evidence, to strengthen its contribution to the ongoing debate about Stonehenge’s bluestones, as evidenced by the scientific consensus in Stonehenge’s Bluestones Were Quarried in Wales 5,000 Years Ago | Sci.News.

www.Sarsen.org

Tuesday, 8 April 2025

A review of "Carn Goedog on Mynydd Preseli Was Not the Site of a Bluestone Megalith Quarry" by Brian John