The Early Devonian Rhynie hot spring system is the oldest known and is of the low sulphidation type. It extends for at least 1.5 km along a major fault zone defining the western margin of an outlier of fluvial and lacustrine sediments, plant-bearing sinters and andesitic lavas. The age of sedimentation and hydrothermal activity has been determined by palynological (Pragian) and radiometric (396 f 12 Ma) techniques. The outlier is a half graben with a complex stepped western margin.The Devonian rocks show intense hydrothermal alteration along the fault zone.The main alteration minerals are quartz, K-feldspar, calcite, hematite and illitic and chloritic clays. Multiple chert veining and brecciation are widely developed, and geyserite and vent material are also present. Pyrite occurs in veins and all alteration facies. Sinters and altered rocks contain high concentrations of Au, As, Sb, Hg, W and MO. Gold occurs in arsenian pyrite and as sub-micron particles in oxidized rocks.The fluid(s) responsible for most hydrothermal alteration were near neutral with low sulphur and oxygen activities and dominated by meteoric water. However, incursions of high temperature (300-440°C) magmatic fluids occurred with SD -65960 and S'*O around +8.59~. 634S (pyrite) and initial *' Sr/%r ratios (vein calcite) lie mainly within the ranges +3.4%0 to +8.5% and 0.71138 to 0.71402 respectively. These data indicate that late Proterozoic Dalradian metasediments are a likely source for S and Sr but other sources are possible. 613C values for caliche and vein calcite imply derivation of carbon from non-organic sources.The Rhynie cherts were deposited from a low salinity fluid of probable meteoric origin (S1'Ochen +13.1% to +16.5%) which had interacted with the basement rocks and sediments (high Xe/Ar, Br/CI and I/Cl ratios). Plant-bearing chert yielded an 40Ar/39Ar ratio (292.1 f 0.6) significantly less than that of modem air and may be the first valid determination of a sample of ancient atmosphere.

Septarian concretions in the Staffin Shales Formation (Kimmeridgian, Isle of Skye) allow controls on concretion rheology and septarian cracking to be investigated. Stratabound concretions consist of anhedral ferroan calcite microspar enclosing clay and minor pyrite. Intergranular volumes range from 77% to 88%, and calcite d 13 C and d 18 O values in most concretion bodies range from )10AE0& to )17AE3& and +0AE3& to )0AE6& respectively, consistent with rapid and pervasive cementation in marine pore fluids. Septarian rupture occurred during incipient cementation, with a sediment volume reduction of up to 43%. Crack-lining brown fibrous calcite records pore fluid reoxygenation during a depositional hiatus, followed by increasing Fe content and d 13 C related to bacterial methanogenesis. Brown colouration results from an included gel-like polar organic fraction that probably represents bacterially degraded biomass. A new hypothesis for concretion growth and septarian cracking argues that quasi-rigid 'proto-concretions' formed via binding of flocculated clays by bacterial extracellular polysaccharide substances (EPS). This provided rheological and chemical conditions for tensional failure, subcritical crack growth, volume contraction, calcite nucleation, and incorporation of degraded products into crack-lining cements. Bacterial decay of EPS and syneresis of host muds provided internal stresses to initiate rupture at shallow burial. Development of septarian (shrinkage) cracks in muds is envisaged to require pervasive in situ bacterial colonization, and to depend on rates of carbonate precipitation versus EPS degradation and syneresis. Subsequent modification of septarian concretions included envelopment by siderite and calcite microspar, hydraulic fracturing associated with Cretaceous shallow burial or Palaeogene uplift; and cementation by strongly ferroan, yellow sparry calcite that records meteoric water invasion of the host mudrocks. An abundance of fatty acids in these spars indicates aqueous transport of organic breakdown products, and d 13 C data suggest a predominantly methanogenic bicarbonate source. However, the wide d 18 O range for petrographically identical cement ()1AE3& to )15AE6&) is difficult to explain.

Clay mineral abundances and illite-smectite (I/S) compositions have been determined by X-ray diffraction (XRD) in shales of Permo-Triassic to Quaternary age from seven wells in the Viking Graben and Moray Firth. Chemical analyses of size fractions provide evidence that diagenetic illitization of smectite has occurred during burial by uptake of A1 and K, and release of Si. K-feldspar was probably the main source of K for illitization. The depth at which random I/S disappears occurs at similar temperatures (mean 93~ in each well for which reliable measurements are available. Vitrinite reflectance measurements at this depth are also similar (mean 0.64% R0) and correspond to early oil generation.

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Clay mineral abundances in Mesozoic and Tertiary argillaceous strata from 15 exploration wells in the Inner and Outer Moray Firth, Viking Graben and East Shetland Basins of the northern North Sea have been determined in <0·2 µm fractions of cuttings samples. The clay assemblages of more deeply-buried samples cannot be unambiguously related to sedimentary input because of the diagenetic overprint which may account for much of the chlorite and related interstratified minerals. Other sediments, discussed on a regional basis and related to the geological history of the basins, are interpreted in terms of clay mineral provenance and control by climate, tectonic and volcanic activity. The distribution of illite-smectite can often be related to volcanic activity both in the Forties area during the M. Jurassic, and on the NE Atlantic continental margin during the U. Cretaceous-Early Tertiary which affected the North Sea more widely and left a prominent record in the Viking Graben and East Shetland Basin. Kaolinite associated with lignite-bearing sediments in the Outer Moray Firth Basin was probably derived by alteration of volcanic material in lagoonal or deltaic environments. Some U. Jurassic and L. Cretaceous sediments of the Inner Moray Basin are rich in illite-smectite, the origin of which is not clear.

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The Square Kilometre Array (SKA) will be the world's largest and most sensitive radio telescope. It will address fundamental unanswered questions about our Universe including how the first stars and galaxies formed after the big bang, how dark energy is accelerating the expansion of the Universe, the role of magnetism in the cosmos, the nature of gravity, and the search for life beyond Earth. This project envisages the construction of 133 15-m antennas in South Africa and 131,072 log-periodic antennas in Australia, together with the associated infrastructure in the two desert sites. In addition, the SKA is an exemplar Big Data project, with data rates of over 10 Tbps being transported from the telescope to HPC/HTC facilities.

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