148 



CAPE COD GEOLOGY 



MAKONIKEY 



About half a mile east of Norton Point, at a place known locally as 

 "Makonikey," there is a clay pit which has been recently worked. The clay 

 here, although undoubtedly Cretaceous, has a somewhat different appearance 

 from that worked elsewhere. This difference may be due in part to its fresh 

 exposure, or the bed may be different from those exposed elsewhere. The 

 clay is a light blue-gray, or even a slightly greenish gray. It has been used 

 for making yellow bricks. The kaolin sand is also found here, but it has not 

 been worked. Mr. Roy Matthews, the former superintendent of the clay works, 

 says the beds of lignite have been encountered near the pit. The section at 

 Norton Point contains beds of lignite. Unlike most of the Cretaceous deposits 

 exposed, these beds appear to be but little disturbed and lie nearly horizontal. 

 Shallow borings in this vicinity strike Cretaceous beds. 



Other localities at which Cretaceous beds are exposed are shown on the map. 

 Many of these exposures are small, but they show the distribution of this 

 series. 



FORM OF THE SURFACE 



The surface of the Cretaceous deposits as it existed before the Tertiary 

 deposits were laid down is shown only in the beds exposed in Gay Head cliffs. 

 The Cretaceous beds appear not to have been then deformed as they now are. 

 They were undoubtedly much eroded before the beginning of Miocene time, 

 but they probably formed an eastern extension of the features of the coastal 

 plain, such as may still be seen southwest of the glaciated area in northern 

 New Jersey. The occurrence in the Cretaceous section of beds of quartz gravel 

 interstratified with beds of clay and lignite suggests that the Coastal Plain 

 became somewhat dissected during the earlier stages of erosion in the period 

 of uplift between the retreat of the sea at the end of Cretaceous time and the 

 beginning of the local Miocene marine invasion. Streams that run parallel to 

 the coast formed bluffs that sloped gently seaward from their crests. Across 

 such coastwise cuestas the master streams maintained consequent courses to 

 their mouths. No recognizable trace of this relief now remains in the district. 



AGE AS SHOWN BY FOSSILS 



Owing to the abundance of Tertiary fossils at the Gay Head cliffs and the 

 fact that little importance was attached to the less conspicuous fossil plants 

 as horizon markers, the early American geologists regarded the Upper Cretaceous 



