Calibration is a necessary step in the workflow for prediction of fault seal because there is no direct way to detect the hydraulic behaviour of a fault at the scale of a hydrocarbon trap. Over the last 20 years two general approaches have been developed: Measurement of hydraulic properties of fault-zone samples (lab calibration), then mapping these results onto the appropriate parts of trap-bounding faults.Design of simple algorithms which attempt to capture a salient feature of the fault zone (e.g. CSP, SSF, SGR), then looking at known trap-bounding faults to find a relationship between the algorithm and the presence or capacity of a seal (sub-surface calibration).Seal capacity is typically described by Hg–air threshold pressure in the lab or static pressure differences in the subsurface (e.g. hydrocarbon buoyancy pressure). In addition to likely interpretation and geometry errors in approaches (i) and (ii), further uncertainty is introduced when converting the calibrated seal strength to potential hydrocarbon column height, because of the variability of subsurface hydrocarbon fluids (interfacial tension). Despite these potential problems, the different methodologies typically agree reasonably well in their predictions for fault-seal capacity. However, this agreement may be largely coincidental and is likely to be a response to the heterogeneity of fault-zone structure (especially at intermediate ‘compositions’ or SGR).

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The NEC deep seismic reflection profile images structures in the lower crust which represent the Iapetus Suture zone beneath southern Scotland and northern England. On the basis of reflectivity characteristics of the lower crust and reflection Moho we recognize four different crustal zones which correspond to four crustal/terrane types: Midland Valley (zone A), a sub-continental subduction complex (zone B ), Lake District (zone C ) and Midland Platform (zone D). The junctions between each of these zones are interpreted as being tectonic. A and B originate from the northern continental margin of the Iapetus Ocean and are separated from C and D (which are derived from a southern continent) by strong northerly dipping reflections between approximately 15 and 30 km deep in the crust. The structure responsible for these reflections does not displace the reflection Moho. North of the AB/CD junction, the base of zone B (and base of the reflective crust) is marked by a pair of parallel reflectors persistent for a horizontal length of about 55 km. These reflectors are interpreted as the top and bottom of a slice of remnant oceanic crust. At their northerly limit the deepest of the two parallel reflectors transects the Moho to a depth of 6-7 km into the uppermost mantle. We suggest that their termination delimits the northerly extent of a décollement or shear zone at the present continental Moho. The shear zone was active during the late stages of Caledonian collision when mantle, originally from beneath the southern continent, underthrust old and newly created crust of the collision zone.

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Acute ethanol administration is associated with sedation and analgesia as well as behavioral disinhibition and memory loss but the mechanisms underlying these effects remain to be elucidated. During the past decade, insects have emerged as important model systems to understand the neural and genetic bases of alcohol effects. However, novel assays to assess ethanol's effects on complex behaviors in social or isolated contexts are necessary. Here we used the honey bee as an especially relevant model system since bees are typically exposed to ethanol in nature when collecting standing nectar crop of flowers, and there is recent evidence for independent biological significance of this exposure for social behavior. Bee's inhibitory control of the sting extension response (SER) and a conditioned-place aversion assay were used to study ethanol effects on analgesia, behavioral disinhibition, and associative learning. Our findings indicate that although ethanol, in a dose-dependent manner, increases SER thresholds (analgesic effects), it disrupts the ability of honey bees to inhibit SER and to associate aversive stimuli with their environment. These results suggest that ethanol's effects on analgesia, behavioral disinhibition and associative learning are common across vertebrates and invertebrates. These results add to the use of honey bees as an ethanol model to understand ethanol's effects on complex, socially relevant behaviors.