Editing Carboniferous rocks around Berwick-upon-Tweed - an excursion

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South of the southerly downthrowing normal fault, the following sequence can be seen in the cliff; burrowed shales, the Lower Bath-House Wood Limestone, c.6 m fossiliferous shales, then the Upper Bath-House Wood Limestone. The latter consists of two limestone units. A 1 m lower leaf is underlain by a 1–3 cm coal. It is separated by 1.5 m of shales from the upper leaf which consists of three beds separated by shaley partings. Bedding surfaces show abundant horizontal burrow traces.
 
South of the southerly downthrowing normal fault, the following sequence can be seen in the cliff; burrowed shales, the Lower Bath-House Wood Limestone, c.6 m fossiliferous shales, then the Upper Bath-House Wood Limestone. The latter consists of two limestone units. A 1 m lower leaf is underlain by a 1–3 cm coal. It is separated by 1.5 m of shales from the upper leaf which consists of three beds separated by shaley partings. Bedding surfaces show abundant horizontal burrow traces.
  
=== Locality 5, Green's Haven Bay [NU 004 538] ===
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=== Locality 5, Green's Haven Bay [NU 004 538] ===
  
North of the fault, the Upper Bath-House Wood Limestone forms the prominent, well '''jointed''' bedding plane surface, dipping 21° northwest. The overlying shales are marine with rare brachiopods at the base, but thin ironstone bands a little higher up suggest a decreasing marine influence. Further north, tiny rippled silty lenses (starved ripples) occur in the thick shales and thicker siltstone, and fine sandstone interbeds with plane laminations, ripples and convolute laminations appear; some of the thicker interbeds have burrowed and '''bioturbated''' tops. Towards the top of this sequence, where the shales become more sandy, a thick unit, containing bulbous '''concretions''', is extensively burrowed and bioturbated obliterating most of the primary sedimentary structures. This is overlain by a thick, 2 m seatearth with black rootlet traces, and a thin 2–20 cm coal. Black, locally burrowed shales beneath the Shotto Wood Limestone succeeded by more shale are exposed approaching the steps ([[:File:YGS_NORTROCK_FIG_03_1.jpg|Figure 3.1]]). The Eelwell Limestone is brown, vuggy and dolomitized in much of its outcrop, but on the northwest side of the paddling pool, it is un-dolomitized and contains abundant ''Gigantoproductus ''brachiopods, together with scattered corals including ''Siphonodendron junceum ''(a distinctive branching coral with close-spaced corallites about 3 mm in diameter). At the northern end of Green's Haven Bay shales occur adjacant to the southwest side of the northwest–southeast trending Green's Haven Fault; on the northeast side is a softish, '''feldspathic''', medium to coarse and locally pebbly, trough and rarely, planar cross-bedded sandstone deposited by currents flowing from the west-northwest ([[:File:YGS_NORTROCK_FIG_03_1.jpg|Figure 3.1]]). The fault plane dips 65° southwest, and shows a dominant oblique slip movement with some dextral translation. The fault can be traced southeast via small reefs of rock into the dome at Ladies Skerrs.
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North of the fault, the Upper Bath-House Wood Limestone forms the prominent, well jointed bedding plane surface, dipping 21° northwest. The overlying shales are marine with rare brachiopods at the base, but thin ironstone bands a little higher up suggest a decreasing marine influence. Further north, tiny rippled silty lenses (starved ripples) occur in the thick shales and thicker siltstone, and fine sandstone interbeds with plane laminations, ripples and convolute laminations appear; some of the thicker interbeds have burrowed and bioturbated tops. Towards the top of this sequence, where the shales become more sandy, a thick unit, containing bulbous concretions, is extensively burrowed and bioturbated obliterating most of the primary sedimentary structures. This is overlain by a thick, 2 m seatearth with black rootlet traces, and a thin 2–20 cm coal. Black, locally burrowed shales beneath the Shotto Wood Limestone succeeded by more shale are exposed approaching the steps ([[:File:YGS_NORTROCK_FIG_03_1.jpg|Figure 3.1]]). The Eelwell Limestone is brown, vuggy and dolomitized in much of its outcrop, but on the northwest side of the paddling pool, it is un-dolomitized and contains abundant ''Gigantoproductus ''brachiopods, together with scattered corals including ''Siphonodendron junceum ''(a distinctive branching coral with close-spaced corallites about 3 mm in diameter). At the northern end of Green's Haven Bay shales occur adjacant to the southwest side of the northwest–southeast trending Green's Haven Fault; on the northeast side is a softish, feldspathic, medium to coarse and locally pebbly, trough and rarely, planar cross-bedded sandstone deposited by currents flowing from the west-northwest ([[:File:YGS_NORTROCK_FIG_03_1.jpg|Figure 3.1]]). The fault plane dips 65° southwest, and shows a dominant oblique slip movement with some dextral translation. The fault can be traced southeast via small reefs of rock into the dome at Ladies Skerrs.
  
From the parking area return to the A1167 (old A1) through Berwick, cross the Tweed Bridge and continue south ([[:File:YGS_NORTROCK_FIG_03_3.jpg|Figure 3.3]]). At the roundabout [NT 996 516] turn left for Spittal and continue to the end of Main Street where there is parking [NU 009 510].
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From the parking area return to the A1167 (old A1) through Berwick, cross the Tweed Bridge and continue south ([[:File:YGS_NORTROCK_FIG_03_3.jpg|Figure 3.3]]). At the roundabout [NT 995 5166] turn left for Spittal and continue to the end of Main Street where there is parking [NU 009 510].
  
 
=== Locality 6, Spittal ===
 
=== Locality 6, Spittal ===

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