GEOLOGY OF THE COAST DISTRICT. 62/ 



6. Kearsarge Group. 



The general character of the rocks of the Kearsarge group has been 

 stated previously. In the Coast District the rocks differ from the mica 

 schists of the Rockingham series principally by the addition of the min- 

 eral andalusite. Hence what has been called Rockingham may prove to 

 belong to this Kearsarge series after the discovery in it of the mineral 

 andalusite. One such case has come to hand since the printing of the 

 sketch of the Merrimack district. Dr. Jackson says he found fibrolite 

 together with garnets and black tourmaline upon McKoy's and Fort 

 mountains in Epsom. The principal area of this rock near the east line 

 of the state occupies most of Rochester, and may be followed into Maine 

 through Lebanon and Acton into Newfield. In Fig. no is a section 

 from Chesley mountain, Farmington, to Rochester village, lying partly in 

 the Rockingham and partly in the andalusite group. This mountain is 

 part of the series of Rockingham elevations from Temple to Teneriffe. 

 The strata are much twisted, with a general south-east dip, and the 

 schists contain beds of granite. Quite near the south base, at M. 

 Thompson's, are the hard rocks accompanying andalusite schists, dipping 

 80° N. The same direction is continuous through the rest of the section. 

 The dips continue high through Farmington, and in the north part of 

 Rochester become much smaller. At D. Rogers's is a bed of quartz 

 similar to those in Raymond. The section shows a sharp synclinal in 

 the andalusite schists resting unconformably upon the Rockingham. As 

 the dip is greater in the south part of the town, were the section pro- 

 tracted farther we might add an anticlinal to the present delineation. 

 The following observations of dips in this area have been preserved, not 

 repeating those already mentioned: 



Rochester. At R. T. Rogers's, dip is<=' N. 50° W. 



At school-house No. 17, dip 50° N. 40° W. In East Rochester, dip 55^-60° N. 60° W. 



At D. G. Ricker's and the brook east, dip In Gonic, dip south-easterly. 



65° N. 10° W. At railroad near Mrs. Trickey's, dip 45° N. 

 The same at J. Foss's and H. Evans's. 10° W. 



At F. Gray's, in north-west corner of the At Mrs. Pike's, in school district No. 20, 



town, dip 85° N. 10° W. dip 10° N. 10° W. 



At Jas. McDuffie's, dip 15° N. 25° W. At Hayes's crossing, dip 30° westerly. 



