4?8 C. H. HITCHCOCK — AMMONOOStrC DISTRICT, NEW HAMPSHIRE' 



attitude and the highly mineralized character. The argillite is identical 

 with that at the west end of the section shown by figure 5. The Lisbon- 

 Swiftwater complex properly begins to the left of the argillite. For a 

 distance of 140 rods it is a mass of quartzites, obscure sandstones, and 

 sericite schists with a northwesterly dip of 50 degrees. There is a slate 

 in the edge of the village past a conglomerate, formerly regarded as the 

 west border of the Swiftwater series. The strata east of this slate have 

 been estimated to aggregate 4,000 feet, those to the west 3,500 feet in 

 thickness. At the crossing of the Ammonoosuc may be recognized a 

 coarse conglomerate variously modified and alternating with hard green 

 schists. To the west are both hard and soft chloritic bands, sericite 

 schists, chlorite-phyllites, and impregnations of galena and chalcopyrite. 

 Near the west border is a large vein of white quartz outcropping con- 

 spicuously for 2 miles north and south, and thus enabling us to believe 

 in a distinct unconformity of the schists beneath the argillites.* The 

 slate belt is the Blueberry range and has the distinction of holding 

 auriferous quartz veins which are now being worked by a company. 

 West of the slates is a strong characteristic development of the argillitic 

 schists, followed by dolomitic slates and auriferous conglomerates. 



A section along Mill brook, in LandafT, should start with the Coos 

 quartzite, which has quite a low northwesterly dip — say 15 degrees. It 

 does not crop out on the stream, but on the high land, both to the north 

 and south. The first rock visible down the stream is much like hornfels 

 with hornblende. Half way to the Ammonoosuc river is a very coarse 

 conglomerate by an old sawmill, dipping 75 degrees north 60 degrees 

 west. It shows more evidences of heat than either of the quartzose 

 ranges. Below this are an obscure schistose conglomerate and vari- 

 ous greenish' schists. At the Ammonoosuc are sericite schists ; all these 

 exposures with northwesterly dips. There are small areas of granite 

 on Green mountain and Pond hill. 



The section along the wild Ammonoosuc is the most typical, passing 

 through the village of Swiftwater. The dips at the east end are higher, 

 being as much as 60 and 70 degrees northwesterly and only 40 degrees 

 on the lower side, suggesting an anticlinal or faulted segments. The 

 first are micaceous, friable, ferruginous quartzites, with intercalated 

 thin glossy black micaceous bands. Next are hornblendic strata and 

 mica schists containing crystals of chlorite. Below the village are mica 

 schists, sericitic, feldspathic, and at length a strong development of slate, 

 followed by a coarse conglomerate midway between the village and the 

 Ammonoosuc. The balance of the distance across to the argillites of 

 the Blueberry range, about 2 miles, is occupied by green schists. 



* Geology of New Hampshire, vol. 2, p. 283. 



