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Leonard Hawkes, during the past three decades one of the elder statesmen of British geology, was one of the few remaining leaders in the subject who received their training before World War I. A lifelong academic, he devoted his best years to the service of Bedford College in the University of London. A very active field-worker in early years, he became in his time a leading authority on the geology of Iceland, pursuing studies in volcanology, igneous petrology and glaciology. He served as a Secretary of the Geological Society of London for a long period at a critical stage in the history of that Society, and was later on its President. He will be remembered as one of the most amiable of characters in the post World War II scene.
The basal member of the Zechstein (Permian) carbonate rock sequence of southeastern Durham is considered the product of accumulation of carbonates and/or mud alternating withaccumulation of bituminous matter during a long slow process of sedimentation. The distribution of most minor elements reflects normal weathering of the land surface, but the contents of zinc, lead, barium, and, in places, copper exhibit a variation that does not conform to any pattern that could be related primarily to rate of sedimentation. Intermittent introduction of the anomalously distributed elements by submarine springs into the lagoonal environment of the depositional basin is probably the most satisfactory of three possible explanations of the source of the abnormally distributed elements.
Summary Honestones from York and certain other early mediaeval sites prove on petrographical examination to include the following rook types: quartz-mica granulite, quartz-muscovite-chlorite-schist, metamorphosed siltstone, silty sandstone, chloritic siltstone, mudstone, phyllite, micaceous sandstone and siltstone, glauconitic sandstone. The metamorphic granulites and related rocks are similar to the schist hones of Mr. G. C. Dunning. The possibility of a source in Aberdeenshire is suggested, perhaps indicating an ancient trade route with the north. Typical phyllites and siltstones from the Lower Palaeozoic rocks of NW. England and the Southern Uplands were probably obtained from the local glacial drift. The sandstones include some Yorkshire Millstone Grit types, while the glauconitic sandstone is undoubtedly from the Greensand of SE. England. It is noted that all the honestones consist of rocks made up of small angular quartz grains set in a softer matrix.
THE finding of a small pebble of fine-grained quartz-dolerite in an exposure of the Upper Brockram in George Gill, near Appleby, by Professor Arthur Holmes in 1925 and its identification with the rock of the Whin Sill led to the direct establishment of the timeof injection of the Whin Sill and related dykes as post-Carboniferous and pre-Upper Brockram (1928, pp. 532–4). Since 1925 parties of students from the Durham Colleges’ Department of Geology have made each year a careful search for similar pebbles not only in the George Gill exposures but in a number of others in the Brackenber Moor neighbourhood. These efforts have not been rewarded with any success until the present year, when a party under my guidance made a thorough examination of the George Gill Brockram and Mr. A. R. Leathley, of Hatfield College, had the good fortune to hammer out a pebble of doleritic aspect.
Mineralization of middle Permian sedimentary rocks of western Europe (Kupferschiefer and correlatives) is not prominent in rocks containing penecontemporaneous vein deposits. Solutions from a deep-seated source formed the vein deposits, and where they emerged at the surface, beneath the waters of the Zechstein sea, their remaining metal contents were precipitated under foul-bottom conditions.
Summary Four cored boreholes drilled in connection with prospecting operations at the Swinhope lead-zinc mine, East Allendale, have provided for the first time in this area, continuous sections of the strata from the Lower Felltop Limestone down to the Great Limestone for geological investigation. The proportion of marine strata is higher than has previously been supposed, and in addition to fossiliferous shale and sandstone includes several thin limestones. The section is compared with Carruthers’ classic Coalcleugh section, and with the sections recorded by the surveyors of the Beaumont mines at Allenheads. An account of the fauna is included.
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