This study has produced records of the palaeosecular variation (PSV) of the earth's magnetic field from Speleothems from China and Spain. The ultimate aim of this project was to produce contemporaneous PSV records which would show that Speleothems accurately record ambient geomagnetic field behaviour. From Sichuan Province, China, five Speleothems were collected of which four were studied for their records of PSV. Eight Spanish Speleothems from the Cantabrian coast were collected but their weak magnetisation allowed only one record of PSV to be produced.
All speleothem sub-samples were weakly magnetised and had, on average, initial intensities of <100 x 10-8 Am2kg-1. Despite this, the majority of sub-samples were stable during stepwise alternating-field and thermal demagnetisation and each displayed a single component of magnetisation after removal of any secondary overprints. Rock magnetic experiments were hampered by low mineral concentrations but suggested that the remanences of each speleothem were carried by a mixture of multi and single-domain (titano-) magnetite and also by haematite present in significant quantities. The primary method of remanence acquisition appeared to be a depositional remanence sourced from flooding. This was corroborated by a linear relationship between sub-sample intensities and weight % acid insoluble detritus.
A selection of sub-samples from each speleothem were dated using uranium-thorium disequilibrium and alpha spectrometry. For the majority of sub-samples the low concentrations of uranium, high levels of detrital contamination and initially low chemical yields raised the associated dating inaccuracies above the quoted level for alpha spectrometry of 5-10%. Two Spanish Speleothems had high uranium concentrations and little, or no, detrital contamination. Percent age errors of these Speleothems ranged from 1 to 6%. Comprehensive experiments on the efficiencies of three electrodeposition methods were also undertaken. The most efficient method was found to be a modified version of the Hallstadius method (Hallstadius, 1984), which consistently achieved chemical yields between 40 and 90% for uranium and thorium.
In order to correct more analytically for the presence of detrital contamination, the leachate/leachate method of Schwarcz and Latham (1989) was tested. The maximum likelihood estimation data treatment technique (Ludwig and Titterington, 1994) was used to calculate dates from these analyses. Tests on Mexican speleothem SSJ2 gave excellent results allowing a revised dating scheme to be adopted. Tests on some sub-samples from Chinese Speleothems were generally unsuccessful due to analytical errors.
The isotope 210Pb was used to date the top surface of one speleothem. A constant growth rate was inferred which was significantly less than that calculated from the 230Th - 234U dating method. This was thought to be due to the former techniques inability to resolve growth rates of periods of less than 200 years.
Despite the dating errors associated with each speleothem the records of PSV compare well with each other and with contemporaneous records from China, Japan and also the UK (for the Spanish record). In addition. agreement with PSV data modelled from observatory records suggested that westward drift of the non-dipole geomagnetic field was predominant during the past 10ka.

A short general introduction, then large photographs and short texts on 28 of the world's great caves, each one selected for some special feature of its geology, geomorhology, biology or history.  Sof Omar (Ethiopia); Sterkfontein (South Africa); Castleguard (Canada); Mammoth (Kentucky); Lechuguilla and Carlsbad (New Mexico); Kazumura (Hawaii); Villa Luz and Sac Actun (Mexico); Quashies River (Jamaica); Janelao (Brazil); Pinega (Russia); Krubera (Georgia); Tri Nahacu (Iran); Difeng (China); Akiyoshi (Japan); Hinboun (Laos); Perak Tong and Mulu (Malaysia); Nare (Papua New Guinea); Nullarbor (Australia); Waitomo (New Zealand); Gaping Gill (England); Chauvet and Berger (France); Alpine Ice Caves (Austria); Skocjanske and Krizna (Slovenia).

The Edwards Aquifer is a large karst aquifer located in south-central Texas USA. The Index Well J-17, in which water levels in the aquifer are continuously monitored since 1934, detected distinctly the March 11, 2011 Honshu, Japan earthquake (9.0 magnitude). The Edwards Aquifer fluctuated approximately 0.3 meters (1 foot) during the initial response and continued to oscillate for approximately two hours after the event.

In this essay, “deep hydrogeology” is somewhat arbitrarily defined as hydrogeology in the subsurface deeper than 1 km, below which the effect of residual permeability at high stresses becomes evident (Neuzil 2003; Rutqvist and Stephansson 2003; Liu et al. 2009). Studies have shown that meteoric fluids are present in the earth’s crust from land surface to at least a depth of 10–15 km (Kozlowsky 1987; Taylor Jr 1990; Zharikov et al. 2003; Ge et al. 2003). At such depths, interaction with surface water and surface events over time periods of 100 or 1,000 years may be minimal, except in areas of very deep mining activities or where deep convection is enhanced by active magmatism. Deep drilling to several kilometers in depth is often done for petroleum and geothermal reservoir exploration and exploitation. The focus of such activities is reservoir identification, capacity evaluation, and fluid and heat extractability. However, it is largely an open area of research to understand the state, structure and evolution of deep hydrogeology over time scales of tens of thousands of years or more, especially in areas lacking petroleum and geothermal resources. Interest in attaining such an understanding has emerged from the need for long-term predictions related to nuclear waste disposal and from recognition of the role that hydrogeology may play in seismicity, orogenesis and various geological processes, as well as in global fluid and chemical cycles. A number of wide-ranging questions may be asked regarding deep hydrogeology, several of which are as follows: What are the current and past states of fluid pressure, temperature and chemical composition in deep formations? How does fluid transport mass and heat? What are the fluid sources and driving mechanisms? What are the magnitude and distribution of porosity and permeability? What are the occurrence and characteristics of large-scale flow, including thermally and chemically driven convection systems? What is the nature of local anomalous fluid pressures and what are their implications? The purpose of this essay is to discuss key issues and research needs in deep hydrogeology. It is based on a workshop on the subject held at Uppsala University in Sweden, with participants from 11 countries, including the USA, Russia, Japan and a number of European countries (Tsang et al. 2012). The following discussion will be divided into sections on permeability structures, driving forces, coupled processes, borehole testing and data analysis, followed by a few concluding remarks.

Tectonic instability may be measured directly using extensometers installed across active faults or it may be indicated by anomalous natural gas concentrations in the vicinity of active faults. This paper presents the results of fault displacement monitoring at two sites in the Bohemian Massif and Western Carpathians. These data have been supplemented by radon monitoring in Mladec Caves and by carbon dioxide monitoring in Zbrasov Aragonite Caves. A significant period of tectonic instability is indicated by changes in the fault displacement trends and by anomalous radon and carbon dioxide concentrations. This was recorded around the time of the catastrophic MW = 9.0 Tohoku Earthquake which hit eastern Japan on 11 March 2011. It is tentatively suggested that the Tohoku Earthquake in the Pacific Ocean and the unusual geodynamic activity recorded in the Bohemian Massif and Western Carpathians both reflect contemporaneous global tectonic changes.