The field excursion this year was to a quarry in the Lower Coal Measures, where we were able to examine mudstones siltstones and sandstones, together with coal seams and fossil trees. In all, the remains of 6 vertical trees were investigated, together with numerous other horizontal branches and roots.
The trees were not growing in a soil, and the discussions of this very significant finding contributed much to our enjoyment of the day.
Four Presentations were made on the second day. Brief outlines are given in this report.
The Formation of Kaolin and the Cornish China Clay industry
The Cornish industry is centred on the St Austell Granite, which continues to be a major producer of china clay for domestic use and for export. The presentation was stimulated by a visit to several of the St. Austell pits in January 2002. The background geology was reviewed by David Tyler, leading to the identification of three significant variables in the kaolinisation process. These are: 1. the composition of the granite, the influence of hydrothermal fluids affecting the granite; the influence of meteoric water in the transformation of minerals. The currently-favoured model of kaolin was reviewed to indicate strengths and limitations. Reference was made to other kaolin deposits in Europe and in the US, as these introduce additional considerations and constraints. What seems clear is that kaolinisation is a complex process, typically followed by intense weathering, and there are indications that the main phase of alteration was geologically quite short. The potential for developing a model of kaolinisation that is consistent with biblical timescales of history is high.
Ordovician trilobites from Central Wales
This presentation was based on the PhD research of Peter Sheldon of the Open University (published in Nature in 1987). A weekend excursion was held earlier this year and attended by Paul Garner. This allowed Paul to see the sites represented by Sheldon’s research, and to gain considerable familiarity with the findings as a result of the researcher’s tuition. Seven sections of strata were studied in greater detail than had ever been attempted before. Altogether, Sheldon collected 15,000 trilobite specimens. When he tried to identify the trilobites, he found small, but significant, deviations from published type specimens. This led to Sheldon mapping gradational change in several of the trilobites represented. The paper attracted controversy, because Darwinians saw it as a vindication of their position, whereas the advocates of punctuated equilibrium were much more cautious. Paul’s review covered many issues, but chief were these. 1. The resolution of the study affects the patterns we see. 2. The trends observed are real, not imaginary. A related aspect of the research was the confirmation of biostratigraphical correlations reported by others, 3. The observed changes are all consistent with what we know of Basic Type Biology. A post-Flood recolonisation model helps us to explain these trends.
Cambrian trace fossils from the Eriboll Sandstone
The 3rd presentation took us to NW Scotland: the Lewisian basement, the Torridonian Formation and the Eriboll Sandstones. The relief of the Lewisian surface is extreme and that soft sediment deformation in the overlying Torridonian is ubiquitous. By contrast, the unconformity with the Cambrian strata is planar. There is no evidence of a deeply weathered surface at the Torridonian surface. The first 90 metres of the Cambrian Eriboll Sandstones are characterised by massive (high energy) cross-bedding and no direct evidences of life. Then comes about 100 metres of “piperock”, fossilised vertical worm burrows. We were shown the main features of these trace fossils and some reasons why they should be considered escape shafts rather than dwelling burrows. The millions of years associated with these rocks bears no relation to the field evidences, which suggest much shorter timescales.
The RATE Project (Radioisotopes and the Age of The Earth)
In anticipation of Andrew Snelling’s visit to the UK in early October, Paul Garner reviewed the work of the RATE group and their recently published book. Paul recommended Russell Humphreys’ chapter on evidences for much radioactive decay in the past. The evidences were drawn from the maturity of radiohalos, the equilibrium proportions of daughter isotopes, fission track data and the Earth’s heat flow data. The conclusion Humphreys draws is that six thousand years of decay at current rates cannot account for these data. Humphreys goes on to argue that there are real trends in the calculated radiometric ages, and these need to be explained. The RATE group have concluded that whilst catastrophism has disrupted radiometric clocks, this is an inadequate response to the observed trends, and accelerated decay rates in the past must be a key part of the reinterpretation. Humphreys also draws attention to independent evidence of accelerated decay rates in the recent past: the large scale retention of helium in the Earth’s crust. There is far too much helium there to be consistent with expected diffusion rates over geological time. However, the data are consistent with accelerated rates in the recent past. A research program to further explore this issue is under way. Paul suggested two areas where there might be fruitful interaction with the RATE group.
This workshop provided a relaxed and constructive forum to develop geological ideas that are consistent with biblical timescales of history. We hope that in future years, other BCS members with an interest in the earth sciences will be able to join us and contribute to our discussions.