Basinwide analysis of sedimentary facies, isopachytes and palaeocurrents for two late Marsdenian (Pennsylvanian) sedimentary cycles within part of the Millstone Grit Group, has led to a new sequence-stratigraphic interpretation for the relationships between its constituent sandstone units (currently named Huddersfield White Rock, Chatsworth Grit, Brooksbottoms Grit, Holcombe Brook Grit, Brown Edge Flags and Redmires Flags). The Bilinguites superbilinguis (R 2c 1) and Verneulites sigma (R 2c 2) marine bands related to fourth-order marine highstands show faunal variations possibly reflecting fifth-order sea-level fluctuations. The lower R 2c 1 cycle consists entirely of deep water mudstone. The overlying R 2c 2 cycle shows an upward regressive passage through pro-delta and delta-slope deposits to mouthbar and channel sandstones. The latter comprises an 'eastern inflow' of northerly provenance, the distribution of which was not influenced by the underlying basement configuration, and a 'southern inflow' sourced from the Wales-Brabant High. Falling sea-levels resulted in progressive narrowing of the fluvial pathway within the main sandstone body of the 'eastern inflow', with a concomitant increase in flow velocities and grainsize. At lowstand, this culminated in the Chatsworth palaeovalley, 25 km wide, the basal surface of which can be correlated into the interfluve areas as a leached palaeosol. Higher sandstone bodies, where developed, are of two kinds: an earlier set present outside of the palaeovalley was formed during regression, and a later set within the palaeovalley was formed as sea level rose. As part of this transgressive systems tract, a Lingula band developed across the flooded Chatsworth palaeovalley and its interfluve margin. The transgression culminated in the highstand of the Cancelloceras cancellatum (G 1a 1) Marine Band. HWR Chatsworth paper vSept07 unformatted.doc 28/07/2008 -2 -This study describes a fluviodeltaic succession within the upper part of the Millstone Grit Group, which outcrops across the central and southern Pennines, around the margins of the Peak District and in the Rossendale inlier (Fig. 1). It is based primarily on observations from surface exposures, supported by information from boreholes (Fig. 2), of the succession deposited within the Bilinguites superbilinguis (R 2c 1) and Verneulites sigma (R 2c 2) sub-biozones of the late Marsdenian Substage (Namurian Regional Stage of the Pennsylvanian) ( Fig. 3). The initial aim of the study was to determine the relationships of a number of sandstone units, namely the Huddersfield White Rock, Chatsworth Grit, Brooksbottoms Grit, Holcombe Brook Grit, Brown Edge Flags and Redmires Flags, the stratigraphical relationships of which are shown in Figure 3.Current nomenclatures for these sandstones are confusing and a simplified scheme is presented. This has led, for the first time, to an understanding of the order in which these sandstones were deposited, and in turn, to a new interpretation of the sequence stratigraphy of this classic cyclic ...
Summary Two major sedimentary basins occur in eastern Libya. The uppermost horizons in each—post-Eocene in the Sirte and Cretaceous Nubian in the Kufra basin—constitute regional hydrogeological systems. The deposits of the Sirte basin include mainly fluviatile sands and clays in the S with marine carbonates and sandy carbonates with some evaporites progressively increasing to the north. In addition to a northwards thickening of the deposits there is an ‘inwards increase’ which attains a maximum thickness of about 1800 m along a broad N-S trending axial trough. The Nubian sandstone of the Kufra basin has a maximum thickness of 900 m and includes mainly cross-bedded sandstones, subordinate shales and conglomerates, which are fluvio-glacial and limnic in origin. The Cretaceous sandstone aquifer in the Kufra basin is essentially phreatic and groundwater flow is to the northeastwards discharging into the main Nubian artesian basin of Egypt. Present development of the aquifer occurs at only a few locations but at these the water quality is very fresh with dissolved solids typically less than 100 mg/1. The basin is bounded to W and S by highlands from which appreciable run-off can be assumed. Although not measured, assumptions of recharge from run-off of some 10–20% of annual rainfall over the elevated areas seems not unreasonable; this is approximately equivalent to the computed order of outflow from the basin of between 70–160 M m 3 /a based on transmissivity and piezometric gradient. Vertical recharge is unlikely to occur over the main basin where the rainfall is probably less than 3 mm/a. The age of the water at Kufra in the north of the basin is in excess of 30 000 years. The phreatic aquifer cannot therefore be in equilibrium with current recharge but it is believed that an approach to equilibrium may exist in marginal recharge areas. The groundwater in the S of the Sirte basin is fresh but in the N it becomes brackish to saline in the direction of flow. The known groundwater ages range from 30 000 to 5000 years BP and fall into three main groups. Water from recent recharge may also exist in the uppermost phreatic levels. Various evolutionary trends have been considered and modelling techniques are used to assist elucidation. The results demonstrate that present water levels may be fairly close to equilibrium, with recharge to the aquifer system occurring from several sources including lateral inflow from the Kufra basin, marginal recharge via run-off from the highlands to the W and SW, and direct recharge from precipitation in the N of the basin. Discharge occurs in the N into sabkhat areas between the Gulf of Sirte and Qattara.
So many sensational accounts of the Moors Murders have appeared since 1965 that our readers will welcome this plain statement of the facts in the case by a senior officer who was principally concerned in its investigation.
SUMMARY The subdrift outcrop of the late Triassic Penarth Group has recently been continuously traced along the eastern side of the Vale of York between Thirsk and Stillington, principally from borehole data. Two new occurrences within this outcrop, a road-cutting near Thirsk and a shallow borehole at Crayke, are recorded. At both, dark-coloured mudstones occur and have yielded palynomorphs and sporadic macrofossils which indicate deposition in a marine environment during latest Triassic (Rhaetian) times. These beds are correlated with the Westbury Formation of the Penarth Group.
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