The Quarterly journal of the Geological Society of London . bove the level of the Eiver Yare. Not only is there herea large pit where the clay is exposed, but the turnpike road is cutthrough it for some distance. Pigs. 2 and 3 will show the position of the deposit relatively tothe other beds of the district. It will be observed that, in fig. 3, the Boulder-clay No. 7 is notrepresented as occurring on the north side of the valley, its placebeing supplied by the coarse plateau gravel No. 8. This gravel ex-tends for some miles over what is known as Mousehold Heath, a pla-teau to the north-east of
The Quarterly journal of the Geological Society of London . bove the level of the Eiver Yare. Not only is there herea large pit where the clay is exposed, but the turnpike road is cutthrough it for some distance. Pigs. 2 and 3 will show the position of the deposit relatively tothe other beds of the district. It will be observed that, in fig. 3, the Boulder-clay No. 7 is notrepresented as occurring on the north side of the valley, its placebeing supplied by the coarse plateau gravel No. 8. This gravel ex-tends for some miles over what is known as Mousehold Heath, a pla-teau to the north-east of Norwich, forming a sheet, in places, from15 to 20 feet in thickness. It has apparently been formed by thedestruction of the Boulder-clay No. 7. That the Boulder-clay No. 7formerly existed on this side of the valley is shown by the presence ofoutliers further to the east. One of these outliers (that at Strump-shaw) is overlain by the gravel No. 8. If these sections be correct, it will appear that the deposit treated 1866.] HAEMEE A THIED BOITLDEE-CLAY. 89. Q — c5 5q i-^ oS7-4 S^i !M ^ « ^ 90 PROCEEDINGS OP THE GEOLOGICAL SOCIETY. [Jan. 9, of in this paper is more recent, not only than the Bonlder-clay No. 7,by the period required for the destruction of the latter and the sub-sequent formation of the great sheet of plateau-gravel No. 8, butthan the gravel itself, by the time necessary for the erosion of a deepvalley, at this point three quarters of a mile in width, and nearerYarmouth much wider. That it is not the Boulder-clay No. 7 thrown down by a fault,and exposed by the erosion of the valley, is, I think, conclusivelyproved by the fact that, in both the cases I have mentioned, the de-posit rests directly on the chalk. At Bawburgh, on the contrary, five miles to the west of the Trowsepit, and eight miles from that at Thorpe, there are several exposuresof Boulder-clay which occur in a precisely similar position in thesame valley, but whose relative position to the chalk is
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Keywords: ., bookcentury1800, bookdecade1840, bookidquarte, booksubjectgeology
