MARINE CRETACEOUS AT NORFOLK, VA. 415 
ground coastal plain geology. Other deep borings have been made in southeast- 
ern Virginia, at Fort Monroe and North End Point, and although they have not 
yielded as definite data as could be desired, they have also added new light to the 
stratigraphy. 
The most important feature of the Norfolk boring has been the discovery of a 
considerable thickness of Marine Cretaceous beds, recognized by unmistakable 
fossil remains. As is well known, the outcrops of Marine Cretaceous formations 
which are so thick in New Jersey thin to the southward and feather out in Mary- 
land a short distance south of Washington. In eastern Virginia the Pamunkey 
(Eocene) formation lies directly on the eroded surface of the Potomac formation 
in the outcropping belt. It was of course to be expected that the Marine Creta- 
ceous beds extended southward, underground, to come out again in the Carolina 
region, but definite data were most desirable in regard to their location and charac- 
teristics. 
In the Norfolk well, which has now a depth of 1,760 feet (December 15, 1897), 
the Marine Cretaceous fossils began to appear at a depth of 715 feet, or possibly 
700 feet, and they were found in great abundance down to a depth of 775 feet. 
Then there was a long interval, mainly of loose micaceous sands, in which no fos- 
sils were found to 1,320 feet, where there is a thin bed of reddish argillaceous sand 
which is supposed to have yielded a single but typical Cretaceous form. The fos- 
sils from a depth of from 715 to 775 feet were all of one species, which is the small 
Exogyra, precisely similar in general form to FE. costata, but having a smooth sur- 
face or showing only very faint costations. They vary in length from } inch to 1} 
inches. The shell from ‘‘1,320 feet’’ clearly is the same species, and although it 
is claimed by the drillers that there can be no mistake about the depth stated, I 
do not feel convinced as to its authenticity. However, it cannot be ignored. 
Through the kindness of the Norfolk and Western Railway officials, I have been 
given the borings of a well sunk some years ago at Lamberts Point, which attained 
a depth of 616 feet. Among these borings, from depths of 568 to 616 feet, there are 
several Marine Cretaceous fossils, including, at 563, 603, and 610 feet, some of the 
EHxogyra above mentioned, and other species, kindly determined by Mr T. W. 
Stanton, which are given in the following list: 
Astarte octolarata, Gabb. Corbula sp. 
Ostrea plumosa, Morton. Modiola sp. 
Gryphea vesicularis. Baculite ? 
Liopistha (Cymella) bella, Conrad. 
The first two are typical Ripley forms. Jiopistha isa Snow Hill, North Carolina, 
form, which also occurs in the New Jersey series. In both of these wells the 
Chesapeake (Miocene) formation extends to within a very short distance of the 
Marine Cretaceous deposits. The intervening Pamunkey (Eocene) formation is 
apparently not over 40 feet thick. 
Two years ago a well was bored at the Chamberlain hotel at Fort Monroe, and 
although I did not see the borings, some of them were obtained by Mr L. Wool- 
man, of Philadelphia, and a much worn shell fragment shown to me by him was 
regarded asa portion of Terebratula harlant. The layer from which this was derived 
is believed to be at a depth of about 840 feet, in a bed of gravel and other coarse 
material, extending from 840 to 845 feet. Mr Woolman has had this shell and 
LXI—Butt. Geo. Soc. Am., Vou. 9, 1897 
