2»S 



SOME ACCOUNT OF THE SURFACE GEOLOGY 

 OF THE DISTRICT NORTH OF GRANTHAM. 



HENRY PRESTON, F.G.S., 



Grantham , Lincolnshire. 



To trace the formation of scenery from geological causes is one 

 of the most pleasant pursuits that can be indulged in, and few more 

 interesting localities could have been chosen to illustrate these 

 effects than that selected by the Lincolnshire Naturalists' Union on 

 the occasion of its visit to Grantham. This is only a small branch 

 of geological study, but it is one which appeals most readily to the 

 general student. 



We cannot here attempt to enter fully into the natural history 

 of the rocks and their fossil contents, nor of the history of the 

 byegone ages they represent ; but we may be able to attempt some 

 account of the district, making special reference to the surface 

 features which owe their origin to geological causes ; and it will be 

 found that here, as elsewhere, elevation and depression of land, 

 coupled with the denuding forces of w r ater, wind, and weather, havt 

 given us all the varied and interesting peculiarities of our country 

 scenery ; they have carved out our valleys and directed the courses 

 of our rivers, and have in every way sculptured the earth's surface to 

 make it beautiful and useful. 



The district visited in June 1896 lies to the north of Grantham, 

 and is contained wholly within sheet 70 of the geological survey 

 maps ; the rocks which rise to the surface are chiefly of Mesozoic 

 age ; and the scenery is truly characteristic of the secondary rocks. 



As will be seen from the section diagram below the whole series 

 of secondary strata cropping out at the surface ranges from the 

 Keuper Marls, through the Rhsetic and Liassic beds, to the Upper 

 Estuarine series which overlie that most interesting formation the 



Lincolnshire Limestone. 





^jlijU^hk- {Mma*****- y<t4iJuJ'&j*AA^. 



A 



B 



c 



D 

 E 



Keuper Marl. 



Rhaetic Beds. 



Lower Lias. 

 ' Scmicostatus ' Band, 

 ands and Clays of Middle 



Lias. 



F 



H 



s 



Mar Is tone. 

 Upper Lias. 

 Northampton Sands. 

 Lincolnshire Limes ie. 

 L r pper Estuarine Series 



Sept. 1896. 



