301:
or from the laying of sewers across
Blackheath. On the northeast side of the Heath, Vanbrugh Pits exposes the typical black flint pebbles in the sides and on the base of the old quarry. On the southwestern edge of the Heath, Eliot Pits were quarried down to the base of the Harwich Formation, the top
241:
The
Tilehurst Member is regarded as a local variant of the Oldhaven Member by the BGS but as a separate unit by other workers. It is found to the west and northwest of London. It consists of glauconitic silt, sandy silt and sandy clayey silt, with sand layers in the form of thin laminae. The unit is
283:
The Hales Clay Member is regarded as obsolete by the BGS, being replaced with the Orwell Member. The Orwell Member is itself subdivided into three parts, known, from the base, as units A, B and C. Unit A consists of up to 1 m of fine-grained glauconitic sands with black gravel and some fossil
250:
The
Harwich Member is regarded as obsolete by the BGS, being replaced by the Wrabness Member. The Wrabness Member is subdivided into a lower Unit A and an upper Unit B. Unit A consists of tuffaceous clayey silts and silty clays, with many layers of
296:
Gravels and sands of the
Blackheath member were at one time extensively quarried across Blackheath. Of the numerous quarries, only two remain relatively untouched, with the remainder being infilled either with rubble from bomb-damaged areas in the
284:
fragments at the base. Unit B conformably overlies Unit A, consisting of up to 1.75 m of bioturbated silty sands and sandy clayey silts, locally with broken shells and dark clay laminae. Unit C, up to 2.5 m in thickness, consists of
224:
The
Swanscombe Member is the youngest member recognised within the Harwich Formation. It is a thin unit, generally less than 2 m thick, but shows a northward increase up to greater than 10 m locally. It is
431:
Edgar, J.; Ghail, R.C.; Lawrence, J.; Skipper, J.; Mason, P.J. (2022). "The impact of facies variability within the
Harwich Formation on ground engineering in the London area, UK".
533:
599:
259:. Unit B consists of fine-grained sand with layers of clay, affected by bioturbation. The Wrabness Member reaches a maximum thickness of 24 m.
267:
The
Oldhaven Member is dominantly a fine-grained glauconitic sand with cross-bedding, lamination and evidence of bioturbation.
229:, generally markedly so. Lithologically it consists of a mixture of sands, silts and clays, locally with shells and
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typically about 2 m thick but reaches a maximum of 7 m. It was deposited in an inner shelf marine environment.
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The
Blackheath Member is a distinctive unit that has been proposed to be raised to formation status.
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233:. It typically has a gravelly base. It was deposited in a mid to inner shelf marine environment.
58:
Swanscombe Member, Tilehurst Member, Harwich Member, Oldhaven Beds, Blackheath Member, Hales Clay
351:
Skipper, J.; Edgar, J. (2020). "The
Harwich Formation in London – The legacy of Chris King".
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Quarterly
Journal of Engineering Geology and Hydrogeology
534:"GLA 65 Old Gravel Pit, Blackheath (Vanbrugh Pit), LIGS"
559:"GLA 24: Old Gravel Pit, Blackheath, Potential LIGS"
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over most of its extent, but may overlie either the
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564:. Guide to London’s Geological Sites
539:. Guide to London’s Geological Sites
204:to the south. It is overlain by the
324:The BGS Lexicon of Named Rock Units
288:sandy silt with fine sand laminae.
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302:of the underlying Lambeth Group.
600:Geologic formations of England
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365:10.1016/j.pgeola.2019.09.001
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509:British Geological Survey
484:British Geological Survey
459:British Geological Survey
407:British Geological Survey
379:British Geological Survey
328:British Geological Survey
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279:Hales Clay/Orwell Member
246:Harwich/Wrabness Member
445:10.1144/qjegh2020-136
206:London Clay Formation
99:sand, silt & clay
67:London Clay Formation
170:geological formation
488:"Blackheath Member"
383:"Swanscombe Member"
320:"Harwich Formation"
25:Stratigraphic range
188:) in age. It lies
595:Paleogene England
590:Geology of London
463:"Wrabness Member"
411:"Oldhaven Member"
271:Blackheath Member
220:Swanscombe Member
176:of southeastern
166:Harwich Formation
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174:London Basin
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148:Type section
142:London Basin
49:Thames Group
227:glauconitic
212:Subdivision
202:Chalk Group
584:Categories
306:References
286:tuffaceous
86:<2-24 m
153:Named for
91:Lithology
83:Thickness
63:Underlies
55:Sub-units
39:Formation
568:18 April
543:18 April
518:18 April
493:18 April
468:18 April
416:18 April
388:18 April
182:Ypresian
180:. It is
112:Location
73:Overlies
29:Ypresian
333:31 July
231:lignite
200:or the
192:on the
184:(early
178:England
157:Harwich
128:Country
122:England
96:Primary
45:Unit of
253:tephra
186:Eocene
138:Extent
117:Region
107:gravel
562:(PDF)
537:(PDF)
439:(1).
168:is a
104:Other
570:2024
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335:2016
164:The
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