New findings on cave science

Hazelton - An digital database of the Biological Records. A demonstration and preliminary analysis

Graham Proudlove
British Cave Research Association Biological Recorder, Department of Zoology, The Manchester Museum, University of Manchester, M13 9PL, UK

The almost total knowledge of the British subterranean fauna is printed in 16 volumes called the "Biological Records". They were compiled and published by the Biological Recorder of the Cave Research Group, Mary Hazelton, between 1955 and 1978 with data from 1938 to 1976. A computer readable version is now being created so that meaningful interrogation of this valuable data set can be carried out. There are approximately 5000 records from subterranean sites country wide including caves and other sites. The presentation will show how the database is created and what it can do.

Speleothem geochemistry and morphology as indicators of variations in rainfall during the Holocene in semi-arid regions

Emily McMillan,
School of Earth Sciences and Geography, Keele University, Staffs ST5 5BG

There is currently a need for more information regarding climate change during the Holocene. Changes in rainfall regime are particularly important in semiarid regions such as southeast Spain. Speleothems provide useful tools for studying variations in precipitation as they can be accurately dated and allow several parameters to be exploited.

Geochemical and morphological characteristics of selected speleothems will be examined from selected active sites together with theoretical aspects of speleothem growth published in general literature. These will be compiled to formulate criteria which will be applied to selected speleothems in order to attempt qualitative analysis of rainfall variation during the Holocene in southeast Spain. The criteria developed will be based around overall speleothem morphology, specific trace element concentrations e.g. magnesium/calcium ratios, isotopic signatures e.g. d18O and the relative chemistry and structure of individual laminae within speleothems.

The overall output of this research should be a set of improved criteria for application in semiarid regions which allows analysis of changes in past rainfall regimes. Wider applications of this study will include the prediction of the possible effects of climate change on such climatically sensitive semiarid regions. The results of this study will be of particular interest when considering the effect of regional-scale climate variations caused by changes in North Atlantic atmospheric circulation.

Auditing the cave archaeology resource

Dr Jim Williams
[email protected], English Heritage, 44 Derngate, Northampton, NN1 1UH and
Dr Jonathan Last [email protected] English Heritage, Fort Cumberland, Fort Cumberland Road, Eastney, Southsea, Hampshire, PO4 9LD

The importance of caves as locations where archaeological and palaeontological material is preserved has been recognised for more than two centuries. In England, the archaeological evidence ranges from the Middle Pleistocene almost to the present day, although cave research has historically concentrated on the Palaeolithic. This chronological bias has an impact on how cave dwelling is perceived by the public; popular images often show grunting, Neanderthal-like cavemen, dragging large cuts of meat into caves with fires, to the visible delight of other, hairy, grunting family members.

One problem affecting the recognition of other periods of cave usage since the Palaeolithic is the lack of synthesis of excavated sites. Understanding the wealth of archaeological material in caves is essential for the development of both future research, and future conservation management strategies. English Heritage has recently reviewed its strategy for caves and rock-shelters. This has identified the need to produce an audit of all the known archaeology of England's caves and rock-shelters from published and unpublished sources, and to assess this against the current deposits within the caves. This presentation will review the elements of this new strategy, and also consider how the protection and management of cave archaeology can be integrated with the work of other conservation agencies, as well as recreational users of caves.

Constructing a karst drainage system: Agen Allwedd.

Helen Dewar
School of Geographical Sciences, University of Bristol, BS8 1SS

The study used the water characteristics of the Agen Allwedd streamway, alongside the inputs, and outputs of the system to infer the physical structure of the aquifer. Thirty seven water samples were collected, of these twenty five were from Agen Allwedd, eight from the peat moorland above and four from the resurgence, samples were collected four times between July 2002 to October 2002. The water characteristics assessed conductivity, temperature, pH, alkalinity, calcium, magnesium, manganese and iron contents to differentiate between flowpaths into the cave. Subsequently inlets were classified as diffuse, fissure or conduit flow.

Additionally depths from up and downstream of the Cascade Passage confluence were recorded hourly over an eleven week period until mid- November. The lag time between rainfall events and rising pool depth was assessed. Response to rainfall was substantially more complex than suggested by the water characteristics. As the system recharged itself the response to rainfall was increasingly rapid, so the importance of antecedent conditions is concluded. In contrast to expectations there is little difference between changes and peaks in pool depth upstream or downstream of the Cascade Passage confluence, so the potential for flooding in this area is believed to be uniform.

"The Ins and Outs of Ogof Draenen", A study of cave speleogenesis

Andy Farrant
British Geological Survey, Keyworth,, Nottingham, NG12 5GG

Discovered in 1994, Ogof Draenen is now one of the longest cave in Britain with a length in excess of 70 km and, at the time of writing, is among the top twenty longest caves in the world. Like other great caves, Ogof Draenen has had a complex multi-phase history. The genesis of the cave is based on speleo-morphologic observations throughout the system. Evidence of at least four phases of cave development, associated with major 180� changes in flow direction and resurgence location can be identified. Joint control has had a dominant influence on passage genesis. In particular it has facilitated the development of maze networks and remarkably shallow, horizontal phreatic conduits. The amplitude of these conduits is much shallower than predicted by models based on flow path length and stratal dip. Here, we suggest that presence of laterally extensive open joints, orientated perpendicular to the regional neo-tectonic principal stress field, determines the depth of flow in the aquifer. Geomorphic observations of former water-table levels in the cave can be related to surface changes in the landscape. This offers a far more detailed landscape evolution chronology than previously available, and suggests that the highest parts of Ogof Draenen are of the order of 1 - 1.5 million years old.

The ontogeny of speleothems

Charles Self
Chairman of Genetic Mineralogy working group, Mineralogy Commission, UIS.

Speleothems are secondary mineral deposits whose growth in caves can be studied by mineralogical techniques. One of these techniques is the ontogeny of minerals, which is the study of individual crystals and their aggregates as physical bodies rather than as mineral species. Ontogeny of minerals as a scientific subject has been developed in Russia but is poorly understood in the West. In this lecture, I will introduce the basic principles of this subject and explain a hierarchy scheme whereby mineral bodies can be studied as crystal individuals, aggregates of individuals, associations of aggregates (termed koras), and as sequences of koras (ensembles). Selenite needles are crystal individuals, most other speleothems are aggregates, while the association (kora) of calcite stalactites and stalagmites is known even to members of the public. Most cavers understand that crystallization in caves is a cyclic process, the product of any one cycle being termed (in ontogeny) an ensemble. Individuals, aggregates, koras and ensembles are classed as "minor mineral bodies" because they can be studied by mineralogical rather than by petrographic techniques.

Ontogeny of minerals is not simply a new classification system for mineral bodies, it is a method by which past crystallization environments can be interpreted. The structure and texture of minor mineral bodies can be directly related to environmental factors at the time of their development. Speleothems are ideal subjects for this type of study, since there are few common mineral species in caves, yet there is a great variety in the forms that these minerals can take.

Active Dolomitisation by Saline Groundwaters in the Yucatan Peninsula, Mexico

Samantha L. Smith1, Fiona F. Whitaker1, R. John Parkes1, Peter L. Smart2, Patricia A. Beddows2, Simon H. Bottrell3
1 Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ
2 School of Geographical Sciences, University of Bristol, Bristol BS8 1SS
3 School of Earth Sciences, University of Leeds, Leeds LS6 2JT

The Yucatan Peninsula is a 300 km wide carbonate platform that hosts a salinity-stratified aquifer where a thin meteoric lens is separated from the underlying saline water by a well-defined mixing zone. An extensive network of flooded caves along the eastern coast permits direct access to the saline groundwaters. Water and wall-rock samples were collected from sites up to 40 km inland and 105 m depth below the water table. Saline groundwaters are depleted of magnesium (-7.7 to -0.1 mM, mean = -3.6 mM) and enriched in calcium (-0.1 to +10.4 mM, mean= +2.3 mM) relative to local seawater, suggesting that these waters have formed replacement dolomites. The pCO2 of saline groundwaters is ~11.5 times greater than that of local Caribbean seawater and they are undersaturated with respect to aragonite (SIA = -0.47 � 0.12) and calcite (SIC=-0.34�0.08). However, the waters are marginally supersaturated with respect to ordered dolomite (SID=+0.18�0.22), providing the potential for dolomitisation.

Some caves host a marked H2S layer. Bacterial sulphate reduction is evidenced by an increase in d34S-SO4, relative to the surrounding saline groundwater, and is supported by the successful enrichment of viable sulphate-reducing bacteria (SRB). Also, compared with surrounding saline groundwaters, the water within the H2S layer is depleted of Ca2+ (by -3.2 mM) as well as Mg2+ (by -4.5 mM), suggesting that sulphate reduction may stimulate primary dolomite precipitation. These findings support previous laboratory simulations that suggest SRB decrease the kinetic barriers to dolomite nucleation. In addition, viable thiosulphate-oxidising bacteria (SOX), enriched from the waters, actively re-oxidise the reduced sulphur species produced by SRB, generating acidity and consequently enhancing the dissolution of carbonate rock. Thus, both SRB and SOX play a role in dolomitisation and carbonate dissolution.

Wall-rock samples from the zone of saline groundwater are partially dolomitised (up to 80%) with both fabric-preserving dolomitisation of grains and dolomite cements lining inter- and intra-granular pores. Preliminary analysis indicates these dolomites are characteristically non-stoichiometric (~41 mol% Mg) and Sr/Ca ratios indicate a seawater origin. No dolomites were found outside the saline zone and dolomite content increases with depth, due to slow incremental dolomitisation over time or dissolution at shallow depths. Dolomitisation is more prevalent within a centimeter of the sediment-water interface and also where there is interconnected porosity. This confirms the importance of the active circulation of Mg2+-rich fluids and/or the significant mediation of diagenesis by bacteria, which are 1-2 orders of magnitude more abundant at sediment-water interfaces, compared with the numbers found in the surrounding groundwater.

How common is diverging flow in karst aquifers?

John Gunn,
Limestone Research Group, Geographical Sciences, The University of Huddersfield, Queensgate, Huddersfield, HD1 3DH

Most models of permeability development in karstic carbonate aquifers are based on an assumption that groundwater flows through a dendritic network of conduits and targets a single, integrative, outlet spring. Whereas it is recognised that a single conduit may discharge through a number of distributary springs and these may exhibit underflow and overflow characteristics it is rare to find acknowledgement or discussion of karst aquifers in which water sinking at one point flows in two or more completely divergent directions. It is possible that this lack of consideration is a consequence of a failure to recognize and monitor all possible outlet points when designing water tracing experiments. In addition, most workers aim to use the minimum possible amount of tracer to avoid visual coloration at the spring. This can result in a failure to detect divergent flow. For example, if 90% of water entering sink 'X' flows to spring 'A' and the remainder to springs 'B' and 'C' then, if the amount of tracer injected at 'A' is just sufficient for detection at 'A' it is likely to be below the limit of detection at 'B' and 'C'. The situation is made worse if the discharge from springs 'B' or 'C' is larger than that from spring 'A'. Repeated tracing experiments in the Cuilcagh Karst (County Fermanagh, Ireland) and in the Peak District (England) have shown that both allogenic and autogenic recharge may target multiple springs several kilometres apart and in completely different drainage basins. This has implications both for models of speleogenesis and karst aquifer evolution and for pollutant dispersal modelling and source area protection.

The feeding relationships of invertebrate fauna within the Peak-Speedwell Cave system

Paul J. Wood, Department of Geography, Loughborough University, Loughborough, Leicestershire, LE11 3TU. and John Gunn, Limestone Research Group, Geographical Science, University of Huddersfield, Queensgate, Huddersfield, HD1 3DH.

Caves are typically food limited when compared to photosynthetically-based epigean systems. A four-year study of the invertebrate community of the Peak-Speedwell Cave system (Castleton, Derbyshire) has allowed the identification of aquatic food chains / webs for several subterranean sites, the Peak Cavern Rising (mainly autogenic fed spring) and Russet Well/Slop Moll, the two main allogenic-fed springs. Energy transfer within Speedwell Cavern and Peak Cavern is dominated by allochthonous organic material transported underground by sinking streams and by percolation water respectively. The spring communities contain elements of the cave fauna, but have been colonised by a wide range of taxa exploiting primary production in the epigean environment. The influence of illumination and lampenflora development, and the impact of pollution, on the trophic structure of subterranean communities will be discussed.

Does quarrying affect water availability in the adjacent unsaturated zone?

Peter Smart1, Cathy Groves2, Elizabeth Cant1, Alice Jones1 and Louise Maurice1.
1) School of Geographical Sciences, University of Bristol, Bristol BS8 1SS England.
2) Dendrochronology Laboratory, Archaeological Research School, Sheffield University, Sheffield S1 4DT, England.

The aim of this study was to examine the possible effect of quarrying on unsaturated moisture availability as indicated by tree growth. Rates of growth were determined by standard ring measurement techniques on duplicate cores from 10 oak trees sampled from a site adjacent to the face of an inactive limestone quarry, and from a more distant matched control site. For each core, the ring width for each year was divided by the mean width for that core over the period 1925 � 2000 to produce a relative ring width index. Data from individual cores were averaged, and then combined to produce an average growth index for each site.

There is clear evidence of covariation in the growth rates at the experimental and control sites that is indicative of external inter-annual differences in regional climate. Regression analysis indicates that there is an inverse relationship between tree growth and average summer potential evapotranspiration, the MORECS soil moisture deficit, the number of sunshine hours in the summer and autumn and the maximum annual temperature recorded in the years during and prior to that of the ring. Spring and summer rainfall (April /May � August) was found to be directly related to tree ring growth. The nature of these relationships suggests moisture availability is a major limiting factor for tree growth, with hot dry sunny summers giving significantly less growth than in cool wet years.

In the early years (1925-1956) there is a general decline in tree growth at both sites, but trees in the experimental site grew at a significantly greater rate than those in the control site (paired t test, 95% confidence interval). From 1956 (when quarrying activities began) to 1978 (some years after quarrying stopped), there is no overall change in growth rates with time, nor a significant difference in growth rates at the 2 sites. After 1978, both sites show a significant decline in growth rates with time, but rates in the experimental plot are significantly less than those in the control plot. The high face of the quarry (2 benches) first approached the experimental site in 1971. There thus appears to have been a significant impact on growth rates at the experimental site, although this has not been sufficiently great as to adversely affect the viability of the trees at the site.

The Life History of the Cave Spider Meta menardi.

Peter Smithers
School of Biological Sciences, University of Plymouth, Drake Circus, Plymouth, Devon PL4 8AA.

Spiders are well known members of the cave fauna being principally associated with the entrance and twilight zones. This study focused on Meta menardi the species most frequently encountered in the twilight zone of caves but which is also found in dark and damp situations such as cellars, air raid shelters, culverts, drains and abandoned mine workings. It is common throughout Europe and North America extending into Asia as far as Korea and Japan.

The work described investigated the life cycle of M. menardi with particular reference to its method of dispersal. The population of spiders in an abandoned mine adit were monitored on a weekly basis over two years, recording the numbers of each developmental stages in various sections of the adit. The results indicate that egg cocoons are produced by females in early summer and spiderlings emerged from them in the following spring . The number of cocoons containing spiderlings correlate well with day length, suggesting that increasing day length may trigger spiderling emergence. Decreasing day length in the autumn correlates well with the number of new cocoons suggesting that this may stimulate cocoon production by females.

The fate of freshly emerged (2nd instar) spiderlings was investigated using an artificial cave. Results indicate that spiderlings exhibit a positive phototaxis and move towards the entrance of the cave.

Observations in the field indicated a protracted period (between October and March) over which 2nd instar spiderlings left their cocoons. The numbers of 2nd instars present in the mine correlated with max temperature, suggesting that an increase in temperature within the chamber may triggered an exodus of spiderlings from the mine.

Once outside the chamber the spiderlings disperse by ballooning. They then construct small orb webs in the low vegetation and feed on small flying insects. In the late summer they begin to seek out dark damp situations and thus find there way back into caves.

Predictive Modelling of Archaeological Caves

Andrew T. Chamberlain, Department of Archaeology, University of Sheffield.

In recent decades predictive modelling has been developed and deployed as a powerful tool for landscape archaeology and cultural resource management. The essence of predictive modelling in landscape archaeology is to identify combinations of topographic and environmental variables that together are correlated with - and hence predictive of - the occurrence of archaeological sites. Most case studies in archaeological predictive modelling have used logistic regression to estimate the probability of archaeology being present, as this regression method yields estimates that range in value between zero (maximum likelihood of site absence) and one (likelihood of site presence). The regression coefficients for the individual variables can be interpreted as weights or scaling factors which encapsulate the contribution that each environmental variable makes to the overall probability of archaeology being preserved at a particular location. A preliminary test of archaeological predictive modelling has been carried out on a set of caves located within a short (4km) section of the Manifold Valley in Staffordshire. The area was surveyed intensively on behalf of the National Trust by professional archaeologists in 1989-92 with a view to identifying the archaeological potential of all of the cave sites in the survey area. The data set includes 84 field-visited caves, of which 17 are classified as archaeological and 67 as non-archaeological. Statistically significant associations with environmental variables include the concentration of archaeological caves at higher altitude locations and with cave entrances positioned on less steep slopes and with aspects facing towards the northern quadrants. Possible explanations for these associations are proposed.

Palaeohydrology in the Eastern Mediterranean from speleothem fluid inclusion D/H analyses

S. McGarry1, M. Bar-Matthews2, A.Matthews3, and A.Ayalon2

1 School of Geographical Sciences, University of Bristol, Bristol BS8 1SS ([email protected])
2 Geological Survey of Israel, 30 Malchei Israel St., Jerusalem 95501, Israel ([email protected]; [email protected])
3 Institute of Earth Sciences, The Hebrew University of Jerusalem, 91904, Israel ([email protected])

The Eastern Mediterranean region, being located in a climate transition zone, was very sensitive in the past to environmental changes such as temperature, amount of rainfall, pattern and origin of storm tracks and changes in the desert boundary, and thus Israel is an ideal location for the study of palaeoclimate change. In order to predict future climate change in an area where human societies and their activities are profoundly influenced by the migration of the desert boundary and the availability of water, it is necessary to reconstruct and understand the continental climate of the past based on a variety of proxy data.

Speleothems are climate-sensitive cave carbonate deposits that record the average surface temperature. The stable isotope composition of speleothems are influenced by temperature, as well as the isotopic composition of the rainfall (D/H and 18O/16O), soil-water interaction and isotopic fractionation in the upper vadose zone. The aim of this study is to gain an understanding of the palaeohydrological conditions in different climatic zones in the Eastern Mediterranean region at various times in the past. This has been achieved by the analysis of the isotopic composition (_18O) of the speleothem calcite and of the coeval speleothem fluid inclusions, (D/H ratios) which act as a proxy for the isotopic composition of the palaeo-rainwater from which the inclusion originated.

The speleothems chosen for this study are from a variety of climatic regimes in Israel and formed during distinct time periods during the past 130 ka, covering 3 glacial and 2 interglacial periods. The fluid inclusions were extracted and analysed by thermal decrepitation (heating calcite under vacuum) (Matthews et al., 2000) and a technique of vacuum crushing was also applied and further developed (Dennis et al., 2001).

The results (_D vs. _18O variations) show a significant range in their isotopic composition but these changes broadly parallel variations observed in present-day rain and cave waters in Israel and suggest the rainwater had its source in the Eastern Mediterranean. In addition the samples show climatic zoning. The isotopic composition of the samples taken from northern Israel reflect the high elevation and rainfall at this site while those of samples taken at the desert boundary clearly indicate the high evaporation and low precipitation in this climate. A temporal trend is also seen in which speleothems formed during interglacial sapropel (wet) periods have isotopic compositions reflecting the markedly higher rainfall during these periods which is in contrast to those speleothems which formed during glacial conditions.

References
Matthews M., Ayalon, A., & Bar-Matthews M (2000), Chem. Geol. 166, 183-191.
Dennis, P.F., P. J. Rowe & T. C. Atkinson, (2001), Geochim et Cosmochim., 65, 6, 871-884.

Amino acids in stalagmites: what do they mean?

Jennifer Moss12, Matthew Collins2, Andy Baker3, Dominique Genty4 and Mabs Gilmour5

1 School of Geography, Politics and Sociology, University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK.
2 School of Civil Engineering and Geosciences, University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK
3 Centre for Land Use and Water Resources Research, University of Newcastle, Newcastle upon Tyne, NE1 7RU, UK
4 Laboratoire des Sciences du Climat et de l'Environnement, LSCE UMR CEA/CNRS 1572 Bat 709, L'Orme des Merisiers CEA Saclay, 91 191 Gif sur Yvette cedex, France
5 Earth Sciences, The Open University, Walton Hall, Milton Keynes, UK

Proteins in living organisms are composed exclusively of L-amino acids. After death, the amino acids interconvert to the optical D-isomer, a process known as amino acid racemization (AAR); the process continues until equilibrium is reached. In the past, AAR has been used as a geochronometer and geothermometer in shells, teeth and bones; the technique has even been applied to ancient carpets.

The amino acids present in soil as a result of decaying organisms is transported with dripwater, and incorporated in very small concentrations (< 3 pmol.g-1 calcite) onto the growing speleothems. Fortunately, using high performance liquid chromatography (HPLC) available in the AAR laboratory at Newcastle University, these concentrations are measurable. Six amino acids and their optical isomers were consistently resolved by HPLC from a 147 cm long speleothem from the Dordogne, France, with ages ranging from 82ka to 33ka before present. The concentrations of individual isomers and the extent of racemization were determined with age.

The D/L ratios were highly variable down core. Using principle component analysis, it was determined that there were three groups of amino acids within which racemization co-varies. One group, consisting of aspartic acid, glutamic acid and serine, was found have D/L values that were inversely proportional to _18O and _13C. These amino acids are known to be prominent in bacterial cell walls, and reflect a bacterial input of amino acids, providing another paleoenvironmental proxy.