A HISTORY OF NORFOLK highly probable that they extend some distance inland beneath the Norwich Crag and Glacial beds, perhaps as far westwards as Happisburgh or Bacton on the north coast, and southwards through Stalham, Acle and Reedham. Although no Eocene fossils have been found in situ in the area, elsewhere the equivalent strata furnish evidence of estuarine conditions and of a tropical fauna and flora. It is noteworthy, however, that some derived Eocene or Oligocene mollusca have been recorded from the Crag;* that Eocene pebbles have been observed in the Glacial Drift of Norfolk ;* and that the jet and amber dredged off the coast or found in the Cromer Forest Bed and on the beach, have probably been derived from Eocene or Oligocene beds under the North Sea. Moreover it is not unlikely that the clayey bands in the Norwich Crag Series were derived from Eocene strata, which locally bordered the sea during the Pliocene period. Be this as it may the record of Eocene strata tells ot a period of quiescent shallow water and estuarine deposits which occupied a considerable portion of what is now East Norfolk, but may not have extended over the entire area of the county. The Chalk towards the west, which was then connected with the Lincolnshire Chalk, must have been upheaved in certain tracts so as to form cliffs which yielded the materials of the Eocene flint pebble-beds. Afterwards, and presumably during the Miocene epoch of which we have no actual deposit in this country, the Eocene strata and Chalk were further up-tilted on the west, and denudation of the Chalk, which had been commenced in Eocene times, was continued by subaerial agents. In course of time the Red Chalk of Hunstanton, which originally may have been 2,000 feet below sea-level, was upraised above it in West Norfolk, and brought to light by the denudation of the overlying beds of White Chalk. We may infer that in these early times the dissolution ot the Chalk and the destruction of the Tertiary strata led to a superficial accumulation akin to the clay-with-flints of our southern counties. A depression in Pliocene times, which affected what is now East Suffolk before any part of Norfolk was submerged, brought in deposits of the earlier Crags, and during later stages much of East Norfolk was gradu- ally lowered beneath the sea-level. At this time probably the North Sea area first began to assume a definite form. NORWICH CRAG AND FOREST BED SERIES The Pliocene deposits which rest indifferently on the Eocene strata and the Chalk, stretch in mass across the eastern part of Norfolk and form the earliest stages of a succession which links us without serious break with the present. There is little doubt that these deposits are represented ' S. V. Wood, 2nd Supp. to Monograph of Crag Mollusca (Palaeontograph. Soc), p. 40.
- Rev. O. Fisher, Geol. Mag.y vol. v. p. 549.
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