Special issue  

We present the interpretation of deep seismic reflection profile ESCIN-2 across the boundary between the Cantabrian Mountains and the Cenozoic Duero Basin (NW Spain). 2-D seismic modelling allowed us to construct a N-S geological cross section which is compatible with the rest of the geophysical data. This profile shows the importance of the N-S Alpine deformation. A wedge of Cantabrian margin crust indented southwards into the delaminated Iberian crust, forcing its northward subduction.

This paper explores the compatibility of seismic and magnetotelluric methods across scales highlighting the importance of joint interpretation in reservoir characterisation. The combination of the two methods together with well-log data at the Hontomín CO₂ storage pilot plant (Spain) allowed a detailed characterisation of the shallow subsurface and defined the structural and fluid flow characteristics of the existing faults, which are key aspects for the risk assessment of the site.

In the present study we present a methodology of how structural geology and geophysics techniques, together with hydrochemical and hydraulic data, can help in identifying the main fractures that conduct most of the groundwater flow in a granitic pluton (low-permeability fractured media). Using the values of transmissivities obtained from 3-D numerical models of the local hydraulic test interpretation, we have been able to reproduce the effect of a large-scale and long-term pumping test.

For this paper, ca. 55 km high-resolution reflection seismic data were interpreted using constraints from magnetotelluric, potential field, and geological data. The resulting integrated geological-geophysical section through the central Caledonides in Sweden provides new insights about the regional tectonic setting, and supplies the basis for siting the second drill hole of the Collisional Orogeny in the Scandinavian Caledonides (COSC) scientific drilling project.

We study the near surface of a complex study area located in Burgos (Spain) characterized by significant changes in shallow geology. The geophysical techniques include measurements of seismic noise (passive seismic) at different points that provide sediment thickness and seismic velocity of the subsoil. On the other hand, geophysical well data help to interpret the passive seismic results. The product of this methodology can be helpful for planning geophysical field surveys in complex areas.

High-grade gneisses record two partial melting events: early Ordovician and early Variscan. Primary sedimentary layering is well preserved locally at the top of the sequence. First stage of the exhumation process occurred in ∼ 10 Ma. Strain was progressively localized along the boundaries of the migmatitic qz-fsp gneisses. Deformation reduced substantially the thickness of the gneissic rock sequence. "Internal" extrusion of the migmatites is documented.

This was an experimental study of the strength of two rock types, over a range of pressure conditions that correspond to depths in the Earth’s crust ranging up to 12 km. Tests were carried out under different stress regimes to simulate extremes of the range of loading geometries encountered in the Earth and hence how these affect failure strength and resistance to frictional slip on faults. These experiments will promote understanding of rock behaviour in oil, gas and water reservoirs.

New stratigraphical, structural, geochemical, and geochronological data from the northern Caribbean orogenic belt indicate that the Imbert Fm constitutes a coarsening-upward stratigraphic sequence that records the transition of the sedimentation from a pre-collisional forearc to a syn-collisional piggy-back basin in the lower-to-middle Eocene. This piggy-back basin was transported to the top of the Puerto Plata ophiolitic slab as it was emplaced onto the North America continental margin units.

The aim of this article is to describe and interpret qualitative and quantitative changes at the rock matrix scale of Cretaceous sandstones (northern Spain) exposed to supercritical CO2 and brine. Experimental CO2-rich brine injection was performed in a reactor chamber under realistic conditions of deep saline formations (P ≈ 7.8 MPa, T ≈ 38 °C and 24 h exposure time). SEM and optical microscopy, aided by optical image processing and chemical analyses were used to study the rock samples.

This study shows the need for a symbiotic relationship between government and research groups for efficient management of geologic data in urban environments. Through its implementation, both the city administration and private companies benefit from the feedback of geologic knowledge acquired during this process, thereby substantially reducing the cost of construction projects and facilitating the development of aquifer management plans.

The period between 1991 and 2005 was a time when many western geologists came to the Urals to get a closer look at this famous and extraordinarily rich region. The main reason was an openness policy of the USSR government, when foreigners were admitted to this area that was formerly almost closed. The co-operation of the western geologists with local specialists was very fruitful. The author aimed to describe the most interesting findings in Uralian geology after the learned guests left.