I50 RESEARCH IN CHINA. 
sandy shales, and clay-shales with frequent bituminous layers. Coal-seams 
of varying thickness and purity are interspersed through this part of the 
series. Toward the top the formation becomes less shaly; yellowish 
white, and brownish sandstones alternate with thin shale beds, completing 
the section. The total thickness exposed is about 750 feet, 225 meters. 
Unlike the Shan-tung coal-fields, these north Shan-si Carboniferous terranes 
appear to be devoid of igneous rocks. 
Cross-bedded ferruginous sandstone with small 
pebbles of quartz and chert. 
Black shale, 15”, 38 cm., in hackly gray shale. 
Black shale, 24”, 61 cm., with thin sandstone. 
Black shale, 12”, 30 cm., layers. 
Sandstone, blocky. 
Sandy shale. 
Thin coal and black shale. 
Hackly gray shale with black shale layers. 
Bony coal, 18”, 45 cm. 
Hackly shale. 
Sandstone, 
Coal, 30”, 76 cm. 
Sandstone. 
Coal, with two thick partings of 6”, 15 cm.,and 
24”, 61 cm.; total thickness, 100”, 254 cm. 
(Bony coal, 15”, 38 em. Bony coal, 30”, 76 cm. 
Shaly gray sandstone. 
Coal, 84”, 213 cm., probably workable. 
Light-gray hard sandstone. 
Gray shale, only partly exposed. 
Coal, 36”, 91 cm. 
Black shale, 48”, 122 cm. 
Coal, 12”, 30 cm. 
Coal, 18”, 45 cm. 
Coal and black slate, 144”, 365 cm., including 
one bed of coal, thickness 30”, 76 cm., which 
is worked. 

Slate and sandstone to base of series. 

ISOFKET 
Fic. 45 (WILLIs).—SECTION OF SHAN-SI COAL-MEASURES IN Trfén-nva District, ATLAS SHEET C I, 
