234 
IOWA ACADEMY OF SCIENCE 
On the top of the divide between Trout run and the next creek 
to the north of it emptying into the Oneota river, on section 20, 
township 98, range 7 west, drift pebbles, gravel and sand are ex- 
posed. The overlying loess is very thin at this place. 
In Clayton County, the whole of Grand Meadow, that part of 
Marion north of the Turkey river, and the west part of Monona 
townships are undoubtedly covered by a drift deposit reaching a 
maximum thickness of sixty feet. Overlying it everywhere is a 
deposit of loess averaging from ten to twenty feet in thickness. 
The underlying rock is Maquoketa. 
The exposures are so numerous that in a drive of a few miles 
on any of the roads traversing that locality a number can be seen. 
Notable ones are near center of section 6-95-6, Monona town- 
ship, on the road from Hardin to Monona; on sections 3, 4 and 5- 
94-6, Marion township, on the Gunder road; and on southwest 
of section 3, on Military road, near center of section 8, in 
the east part of sections 29 and 32, on north and south road, neai 
center of section 11, and near center of section 23, all in Grand 
Meadow township. 
All are the usual exposures at bottom of ditch by roadside. 
On the southeast quarter of section 20 of this township, sixty feet 
of sand and till were penetrated in drilling a well before the under- 
lying Maquoketa was struck. 
Near the northeast corner of section 19 in the same township is 
a deposit of stratified sand, twenty feet of which has been exposed 
in digging out for building purposes, and on the southwest of 
section 8 and northwest of section 21 are other “sand banks” from 
which hundreds of loads have been removed for building. 
All exposures in this section are probably Iowan. 
On the road from Monona to Elkader, on the section line between 
sections 11 and 12, Wagner township, and near the center and also 
the south line of section 24 of the same township, thin exposures of 
red clay with greenstone and quartz pebbles are seen underlying the 
thick mantle of loess. On the top of the hill, on the same road, one 
mile out of Elkader, resting on the Galena-trenton limestone, ten 
feet of drift of the same character can be seen. 
On mile west of Froelich, in section 29, in Girard township, in 
ditch on north side of road, five feet of clay with characteristic 
drift pebbles can be seen. Half a mile east, linemen in digging 
holes for telephone poles, struck sand two feet below the surface 
into which they penetrated three feet. 
