THE COAL-FIELDS OF ALASKA* 



With a Few Notes on the Mineral Wealth of the 



Territory 



THERE are two known areas of 

 high-grade coal — the Bering River 

 field, in the Controller Bay region, 

 and the Matanuska field, north of Cook 

 Inlet. The Bering River field, lying about 

 25 miles from tidewater at Controller 

 Bay (see map, page 24), embraces 26.4 

 square miles underlain by anthracite and 

 20.2 square miles underlain by bitumi- 

 nous coal. The coal-bearing rocks trend 

 to the northeast into the unsurveyed high 

 ranges, and it is quite possible that there 

 may be an extension of the coal-fields in 

 this direction. 



Coal-beds varying from 6 to 20 feet in 

 thickness are exposed in this region, with 

 some local swellings, giving a much 

 higher maximum thickness. In quality 

 the coals vary from an anthracite, with 

 84 per cent of fixed carbon, to a semi- 

 bituminous, with 74 per cent of fixed 

 carbon, and include some varieties that 

 will coke. There has been much pros- 

 pecting of these coals, but in the absence 

 of railways no mines have been devel- 

 oped, though a small output from one 

 bed has been taken to the coast in barges. 

 The Matanuska coal-field lies about 25 

 miles from the tidewater at Knik Arm, 

 a northerly embayment of Cook Inlet. 

 As Cook Inlet is frozen during the win- 

 ter, however, the distance to an open 

 seaport must be measured to Resurrec- 

 tion Bay, on the east side of Kenai 

 Peninsula, about 150 miles from the 

 coal-field (see map, page 3). 



The known commercially valuable coals 

 of the Matanuska field vary in quality 

 from a sub-bituminous to a semi-bitu- 

 minous, with some anthracite, and are 

 included in folded and faulted Tertiary 

 (Eocene?) shales, sandstones, and con- 

 glomerates, aggregating 3,000 feet in 

 thickness. 



The coal-beds vary from 5 to 36 feet 

 in thickness, and the total area known to 

 be underlain by coal aggregates 46^^ 

 square miles. However, as much of the 

 field is covered by gravels and none of 

 it has been surveyed in detail, the coal- 

 bearing area may be much larger. The 

 total area of what may prove to be coal- 

 bearing rocks is approximately 900 

 square miles. Up to the present time 

 there has been no means of transporting 

 this coal to market, so that no mining 

 has been done, but many beds have been 

 opened in prospecting. 



The anthracite from Matanuska and 

 Bering rivers has no equivalent on the 

 Pacific Coast, and it compares favorably 

 with the Pennsylvania anthracite. It 

 ought to be put into the San Francisco 

 and other Pacific Coast markets at a cost 

 far below that of Eastern coal, in which 

 case it should have no difficulty in en- 

 tirely supplanting the latter. 



The Bering River semi-anthracite and 

 part of the semi-bituminous coal from 

 Matanuska is also better than anything 

 that is being mined in the West. These 

 coals are the equivalent of the Poca- 

 hontas, New River, and Georges Creek 

 coals of the East, and are eminently 

 adapted for use on warships and for 

 other purposes for which a high-grade, 

 pure, "smokeless" steaming coal is re- 

 quired, and for these purposes will com- 

 mand a considerably higher price than 

 any coal now being mined on the Pacific 

 Coast, or, if offered at equal prices, 

 should readily drive the latter from the 

 market. 



Part of these coals will produce an 

 excellent quality of coke — better, in fact 

 (except possibly in content of phos- 

 phorus, regarding which no data are 

 available), than coke which can be pro- 



*From reports of Alfred H. Brooks, Chief of Alaskan Division, U. S. Geological Survey. 



