Vol. 69.] THE CLEVELAND DISTRICT OF YORKSHIRE. 249 



VII. Notes on the Stratigraphy op the Marske Quarry. 

 (G. J. L.) 



A range of elevated ground starts from the sea-coast in the 

 lofty cliffs of Huntcliff and Boulby, and, striking westwards, 

 divides into two lines : the northern forming the outlying hills 

 of Upleatham and Eston, the southern passing to the south of the 

 great inlet in which the town of Guisborough lies, where it forms 

 that part of the Cleveland Hills known as Guisborough Moor. 



The Marske Quarry is situated on the northern face of the 

 Upleatham Outlier, about a mile from the village of Marske-by-the- 

 Sea. The quarry has not been worked for the last twenty years, and 

 parts of it are inaccessible through fallen rubbish. Its altitude 

 above sea-level is 500 feet. 



The complete succession of the Lower Oolites in Yorkshire tabu- 

 lated by Eox-Strangways is as follows, in descending order : — 



Cornbrash. 



Upper Estuarine Series. 



Grey Limestone Series. 



Middle Estuarine Series. 



Millepore Bed. 



Lower Estuarine Series, with Ellerbeck Bed. 



The sequence of the beds in the Marske Quarry, from careful 

 measurements taken of the best-exposed section, is as follows : — 



Thickness in feet inches. 



1. Glacial drift and clay 1 



2. Shaly sandstones ... 8 4 



3. Ferruginous shales 1 



4. Shaly sandstones 2 



5. Coaly shales 2 6 



6. Shaly sandstones 6 6 



7. Ferruginous bed 1 



8. Massive, false-bedded sandstone. 20 



Beneath this lowermost bed lies the Dogger. This latter deposit, 

 so useful for demarcation between the Lias and the Oolite in North- 

 East Yorkshire, is not exposed in the quarry, but crops out beneath 

 the sandstone on the flanks of the Upleatham Outlier. The geological 

 horizon of the Marske Quarry may therefore be fixed as the Lower 

 Oolite, and as belonging to the Lower Estuarine Series of Eox- 

 Strangways's classification. As the Millepore Bed is absent in this 

 locality, the Lower and Middle Estuarines may be regarded here as 

 one continuous deposit. 



Lithologically, the quarry reveals many varieties of rock, and 

 much variation is observable throughout the quarry in the thickness 

 of the strata exposed. The coaly, sandy, and ferruginous shales, 

 which are all strikingly lenticular, vary in different parts of the 

 quarry from a foot to the thinness of a sheet of notepaper. The 

 arenaceous bed at the base of the quarry is of considerable thickness. 

 It is also strikingly lenticular, false-bedded, and blotched with 



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