Bulletin - New York State Museum . ot of this ridge in North Albany theclays are seen resting unconformably on these older glacial grav-els. The gravels are locally very coarse and bouldery, layers ofsmall boulders up to 1 foot and even 15 inches in diameter beingseen well up in the section. The beds have a strong dip towarda depression on the north of this locality as if they had settled. i;iO MOW YORK STATE MUSEUM The relation ol (Ih/ cIjivs to tlie older gravels shows that thegravels were cut off on the south by running water so as to forma well defined hank. Down this bank cobbles and boul
Bulletin - New York State Museum . ot of this ridge in North Albany theclays are seen resting unconformably on these older glacial grav-els. The gravels are locally very coarse and bouldery, layers ofsmall boulders up to 1 foot and even 15 inches in diameter beingseen well up in the section. The beds have a strong dip towarda depression on the north of this locality as if they had settled. i;iO MOW YORK STATE MUSEUM The relation ol (Ih/ cIjivs to tlie older gravels shows that thegravels were cut off on the south by running water so as to forma well defined hank. Down this bank cobbles and boulders < liiys began to deposit in horizontal layers againstthe bank, indicating a change from powerful streams of waterrunning over the surface and cutting deeply into its drift depositsi(» a time of quiet silt-laden waters. Further indications of the mode of building of these oldergravels occur in a pit in the same vicinity. The structure is thatof an aggraded deposit of gravels with extremely coarse lenses. Fig. IG Cross-section of a^frraded glacial gravel deposit at North Albany, showingleDses of coarse gravel in old stream bed. [See also pi. 9] showing where the stream bed as it wandered from point to pointin the building up of the deposit happens to appear in the above figure illustrates the general cross-section of the pit. Moluiwk delta. The extensive sand and clay plains developedon the Albany and Schenectady quadrangles in the towns ofBethlehem, Guildorland, Watervliet, Niskayuna and Rotterdam,south of the Mohawk river, form an ancient delta of that riverand are the most extensive deposits of this nature in the Hudsonif not also in llu (Miaiiiplain valleys. The deposit, clayey belowand near I lie Hudson gorge, gives way to sands toward the north-west and in I lie upper sections. Along the Hudson gorge thedeposit fills in depressions in the rock bench and mantles thisolder toj)(>grai)hy excej)t at such localities as the Abbey at Glen-mo
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887