The Wildmoor Sandstone Formation, proved in three boreholes drilled at Birmingham University, is dominated by fine- to medium-grained sandstones deposited in a braided river environment, within which channel lag, channel fill and abandoned channel facies are recognized. Minor proportions of aeolian sandsheet are present, as are dolocretes, not previously reported in the formation.The sandstones are feldspathic and lithic arenites, and typically are clay-poor. Early dolomite dominates the diagenetic overprint, and is preferentially developed in channellag deposits. Burial diagenetic effects are minor. Late calcite occurs as a pore-filling phase and within fractures.Minor fractures and granulation seams are oriented parallel to the NE-SW Birmingham Fault. ‘Conventional’ granulation seams, with comminution of detrital material, and more complex seams containing comminuted dolomite cement with a millimetre-wide halo of dolomite cement are present, the latter implying that the sandstone was dolomitecemented at the time of fracturing.Several scales of heterogeneity will affect groundwater solute transport. The palaeosols and abandoned channel mudstones may act as barriers to vertical flow at the decimetre scale. Dolomite-cemented channel-lag deposits may act similarly at smaller scales. Granulation seams have permeabilities of two-three orders of magnitude lower than their host sandstones, but their limited occurrence may limit their impact on larger scale flow. Matrix permeability is controlled by grain size and dolomite cement.The fines in the fine-grained, ripple cross-laminatied sandstones were extensively washed out during coring, and this lithology may be a source of sand yields in some sandstone boreholes. Although no enhancement of particle yields was seen during packer testing, the possibility remains that more comprehensive failure may occur at higher pumping rates.

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The North Pennine Orefield Alston Block has produced approximately 4 Mt Pb, 0.3 Mt Zn, 2.1 Mt fluorite, 1.5 Mt barite, 1Mt witherite plus a substantial amount of iron ore and copper ore from predominantly vein-hosted mineralisation in Carboniferous Limestones. However, a significant proportion of this production (c. 20 %) came from stratabound deposits. Though much is known about the vein-mineralisation, the relationship between the veins and the stratabound mineralisation is not well understood. New petrographic, isotopic and fluid inclusion data derived from samples of stratabound mineralisation allow us to present a unified model that addresses the genesis of both the vein and stratabound styles of mineralisation. The mineralisation can be Bouch et al.Pennine Pb-Zn-Ba-F mineralisation 3

Synopsis Minor occurrences of nepheline syenite are present in a hypabyssal intrusion composed predominantly of alkali olivine dolerite, at Cnoc Rhaonastil, Islay. Their mineralogy is dominated by albite and kaersutite, but minor, strongly zoned sodic pyroxenes of the hedenbergite-aegirine solid solution series are present. These pyroxenes contain up to 5.30 wt% ZrO 2 . Two Zr-rich end-member substitutions are important: (1) NAZAL (NaZrAlSiO 6 ) and (2) FM-NAZ (Na(Fe,Mg) 0.5 Zr 0.5 Si 2 O 6 ), although the latter is probably dominant. There is no clear overall interdependence between zirconium content and pyroxene end-member compositions, implying crystallization was from localized Zr-rich domains in a residual felsic liquid. The earlier crystallization of pure calcic catapleiite (CaZrSi 3 O 9 .2H 2 O) may have caused localized depletions in the Zr content of the melt. As far as we are aware, this is the first reported occurrence of zirconian aegirine from Scotland, and only the second reported occurrence of stoichiometric Ca-catapleiite in the literature.