Bulletin - New York State Museum . its marginis to be suspected in the case of the contorted clays in the basalportion of the section on Crotou point; but the contortions can ^Emmons, E. 1847. See bibliography, 53. ^Dwight, W. B. 188G. See bibliography 45. UuRsoll, I. C. Lakes of North Am orien. Boston 1895. , I ANCIENT WATER LEVELS OF CHAMPLAIN-HUDSON VALLEYS 189 not be taken as a criterion of the presence of the glacier unless in-dependent evidence of the presence of the ice be found and evenin this case the direction of the overthrnsting movement shown bythe clays should agree wi
Bulletin - New York State Museum . its marginis to be suspected in the case of the contorted clays in the basalportion of the section on Crotou point; but the contortions can ^Emmons, E. 1847. See bibliography, 53. ^Dwight, W. B. 188G. See bibliography 45. UuRsoll, I. C. Lakes of North Am orien. Boston 1895. , I ANCIENT WATER LEVELS OF CHAMPLAIN-HUDSON VALLEYS 189 not be taken as a criterion of the presence of the glacier unless in-dependent evidence of the presence of the ice be found and evenin this case the direction of the overthrnsting movement shown bythe clays should agree with the axis of movement of the ice this movement in the clays would be away from the ice contactterrace it should be possible to discriminate in favorable situa-tions contortion through gravitative sliding from contortion by icethrust. In the Croton point case, there is evidence of the presenceof the ice in the morainal revetment of the remaining portion ofthe old ice contact terrace on the north and the contortions have. Fig-. 23 Contortion and intrusion of clays in sand bank south of Port Kent railroadstation, as seen July : A, the clay ; B, the foresei sands of the delta ; C, upper uostundisturbed sand layers their axial planes thrown over to the south away from the ice,hence it is possible to infer that a slight ice thrust is indicatedhere. The case is described elsewhere in this report in which the icesheet has overrun clays in the Hudson gorge between Schuylervilleand Fort Edward, producing contortions of large size. At many points where streams have constructed deltas on themargins of the clay area crumpling is to be suspected as an effectof the weight of the overlying sand and gravel. A rather markedcase, probably a locality earlier observed by Ebenezer Emmons, isthat of the southernmost lobe of the marine delta of the Ausableexposed in a section south of the railroad station at Port Kent onLake Champjain. The sands which have here been deposited overth
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