240 



a few miles lieconies iiuicli shallower. Tlio bluffs hecome low aiul for 

 some distance on the east side entiicly disapiieai' at a \vide sap opening 

 into an extensive prairie to the east. .lust lielow this the northeast hluff 

 becomes considerably higher than the one on the opposite side of the 

 stream. About two miles below a ch-ep broad valley Itegins and continues 

 to the Wabash flood-plain. The lower course of the Wea for several nilles, 

 is cut tlirough the Wea Plains terrace and the Wea Valley itself is terraced. 

 The levels of parts of the terrace farthest up stream conform apparently 

 to the surface of the AVea I'lains. 



The peculiarities of valley and cou.rsi' noticed in these streams invite an 

 attempt at exi»lanation. This is found in tlie interpretation of the glacial 

 features of the region. 



By reference to the map it Avill lie noticed tliat several moraines cross 

 the county south of the Wabash Itiver. The one forming the divide be- 

 tween the Wea system and the streams to the southwest extends south- 

 eastward across the southwest corner of the county. Another extends east 

 along the south side of the ^^'ea Plains terrace to a point nearly south of 

 LaFayette, where it bends to the southeast and continues to the southeast 

 corner of the county. Between these ridges others trend east and Avest. 

 All the ridges together thus form a comiilex iietworl;. Enclosed by the 

 ridges are tracts of level i)rairie formerly marsliy over large areas but 

 noAV generally drained. 



The creeks cross these tial inairics. cut through some of the ridges and 

 follow along tlie sides of others. 'I'lie Wea streams are entirely post- 

 glacial in tlieir origin atid liistory. Tlieir channels are cut in the lieds of 

 glacial drift that overlies tlie cotmtiy. tlie underlying lied-rock being 

 reached and exposed for a dista.iice of a few rods in only oiu' phne in all 

 the Wea system. This is in the bed (jf Little Wea Creek where it enters 

 the Wea Plains terrace. 



The retreat of the ice slieet from rliis region uncovered the basin of 

 the Wea Creeks before it did the iiresent course of the Waliash River. 

 It may be that melting of tlie ice between the ;Michigan and Erie lobes 

 occurred across the course of the Wabash River ami along the Tippecanoe 

 River, while the Wabash, farther west, was still obstructed to a much 

 later period. This caused the Avaters of the melting ice to gather along 

 the front of the ice border until they covered the whole Wea basin and 

 flowed out at the sags across the divide where the heads of the Wea Creeks 

 are so near the heads of Shawnee. Coal and other creeks. This Avould 



