ALLEGHENY FORMATION OF WESTERN PENNSYLVANIA BASINS 99 



Ft. In. Ft. Ft. Ft. In. Ft. In. 



Interval 40 45 47 50 ~\ 



Middle Kittanning 13 2 2 3 8 I 66 6 



Interval 48 30 ^ 37 ) 



Lower Kittanning 2 6 4 (- 64 3 3 6 



Interval 35 33 J 25 40 



Vanport limestone 50 4 4 70 10 



Interval \ t 22 



Clarion I . . . . . . 50 . . . . J 2 2 



Interval j (23 



Brookville . . . . . . . . Thin 



to the Pottsville. The interval from Upper Freeport to Lower Kittan- 

 ning in the three sections showing both beds is 198, 220, and 176, and to 

 the Vanport 235, 271, and 219 feet, the last in the southwest corner of 

 the county. At one mile north from III the interval between Lower 

 Freeport and Upper Kittanning is but 40 feet, and at two miles south, in 

 Armstrong county, it is only 25 feet, showing a variability in this interval 

 such as has been noted already in southern Elk. Of the limestones, the 

 Upper Freeport is widely distributed, the Lower Freeport and Johnstown 

 cement are irregular, while the Vanport seems to extend in prongs toward 

 the northwest. The Butler, Freeport, and Kittanning sandstones are dis- 

 tinct in the southern townships, but elsewhere their places are filled for 

 the most part by shales, while the Clarion is a well marked sandstone, 

 20 to 30 feet thick, in most of the county. The Upper Freeport coal bed 

 is good, with little variation in thickness, but the other beds are of no 

 importance except the Upper Kittanning, which, in a small area within 

 Porter township, has a cannel roof of 8 feet.* 



Armstrong county, south from Clarion, west from Indiana, and north 

 from Westmoreland, has for its southern boundary the Kiskiminetas, the 

 continuation of the Conemaugh river. In the easterly part of the county 

 the section is followed easily from Clarion line to the Kiskiminetas, 

 though the intervals between the coal beds show notable variations. The 

 Scrubgrass, or Upper Clarion, coal bed does not appear in any of the sec- 

 tions, but the others are persistent, though the Upper Freeport and 

 Lower Kittanning are the only ones of economic importance. The Upper 

 Kittanning has a cannel roof 8 feet thick in a small area adjoining 

 Clarion county, but the cannel is inferior. The LTpper Freeport and 

 Vanport limestones are persistent except in a small area central in the 

 county where the lower bed seems to be wanting. The sandstones are in- 

 significant and their places in almost all of the sections are filled with 

 shale. 



* H. M. Chance: Clarion (V V), pp. 70-71, 75, 77, 79, 80-81, 88, 90-91, 95, 97, 103, 

 107, 112, 121, 123, 125-126, 132, 136, 142-143, 147, 153, 158, 160, 175-176, 178, 181. 



