1865.] 



FISHER CHILLESFORD REDS. 



21 



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gathered; but not being satisfied with my 

 proofs, I determined to make a careful section 

 from Orford to the Thorpe pit, and at my 

 second visit walked over the ground for this 

 purpose. 



To some extent the section will explain 

 itself, but I desire to advert to a few parti- 

 culars of it. 



The chief difficulty in the geology of this 

 neighbourhood arises from the repeated ero- 

 sions which the surface has undergone, the 

 newer beds being thrown down upon the eroded 

 surfaces of the older. ^ 



One consequence of this is that we ordinarily 

 find the succession incomplete. Another is 

 that any given deposit does not continue of a 



uniform thickness, but while its upper surface, 



where it has escaped erosion, is nearly hori- 

 zontal, the lower follows the contour of the 

 surfaces of the rocks on which it rests. s^, o 



Another difficulty arises from the sandy beds ^ q 

 of the district being so similar to one another, '^ ^ 

 that it is difficult to distinguish them by their 

 lithological features. 



As far as my notice extended I did not see 

 any indication of faulting, and the dip of the 

 beds appeared very regular, being very slightly 

 towards the north. 



The section commences at the Orford wind- 

 mill, which is marked on the Ordnance Map 

 as being 54 feet above the sea-level. Here 

 the beds are capped by a drift gravel 7 feet 



thick. It contains large flints and quartz ■ 



boulders, eight or ten pounds in weight. It 

 rests on the Chillesford Clay. 



The clay or loam is seen in a small pit '^^ 

 beyond Queen Esther Grove. It is exposed ^W 

 for 10 feet, and rests on reddish-yeUow sheUy p, |i 

 sand. At the interval of one field the sheUy ^ 

 sand is seen beneath the hedge. A quarter 

 of a mile further on, at Sudbourn Church 

 Walks, is a shallow pit in brown micaceous 

 loam. The shelly sand, always more or less 

 noticeable below the ChiUesford loam, is well 

 exposed in the bottom of this pit. A small 

 excavation which I made disclosed the Mya- 

 bed in great perfection. It was about 2 feet 

 thick, with three or four tiers of the united bi- 

 valves. They lay so close together that it was 

 impossible to remove one without breaking 



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(Sudboura 

 { Church 

 i Walks. 



IL- ^ SuJbourn. 



Marsh. 



TJiver Aide. 



Aldborough 

 town brick- 

 field. 





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O 



4 



Aldborough 

 ' old brick- 

 kiln. 



Ttorpe 

 ahell-pit. 



