276 GEOLOaY OF THE I^TAERAGANSBTT BASIK 



the coaly shale, and dipping 45^ E. If this indicates an anticline, it is 

 evidently a sharp one, and the folding has been obscured in the shales by 

 abundant cleavage in several directions. It is also a long fold, extending 

 from the most northern shale exposure for at least half a mile southward. 

 The sandstone, dipping east, at the north has a strike of about N. 5^ E., 

 following the shore for a considerable distance, and at the south end the 

 strike clianges to N. 30° E., the dip being 50"^ SE. Beyond this is a fault 

 having the same trend of N. 30° E. 



In some places the sandstone is very coarse and contains a great 

 number of small pebbles Toward the fault the sandstone is often very 

 quartzitic, somewhat resembling the arkose along the shore, but the quai^tz 

 grains are as a rule much smaller in size. South of the fault line the shore 

 is bordered by sandstone, often coarse, or filled with small pebbles; less 

 frequently it is decidedly conglomeratic, with much stretched pebbles. Just 

 south of the fault a fine conglomerate bed was once overlain by black shale, 

 small patches of which are still scattered over its surface, indicating a 

 general southerly dip of about 20°. Farther south the strike is N, 70° W., 

 dip 25° S., but there is also evidence of cross bedding, suggesting shallower 

 water eastward. Near the most western extension of the shore a long 

 plant stem is exposed for several feet in the coarse sandstone, but shearing 

 makes it impossible to identify it. Small plant stems occur near by, resem- 

 bling the Silver Spring plant stems. Farther south, at the western termina- 

 tion of the Almy Farm road to the shore, the coai'-se sandstone, containing 

 numerous fine pebbles, shows a strike of N. 60° W., dip 20° SW., indicated 

 by numerous patches of coaly shale, which cover its surface and which 

 once were connected and formed a continuous layer. 



Southward from this region the bedding is often difficult to follow for 

 any considerable distance. Not infrequently the strike is nearly east- west, 

 and the dip is then southerly, usually about 20°. But at many points along 

 the shore there is bedding striking more nearly parallel to the shore and 

 dipping westward, often very steeply. In some cases, especially where the 

 dip is very steep, this west dip seems to be partly due to folding caused by 

 pressure transvei*se to the trend of the border of the basin Frequently, 

 however, it is accompanied by distinct evidences of cross bedding. In such 

 cases a steep westward dip not infrequently curves westward so as to reach 



