Page 535 |
Previous | 535 of 628 | Next |
|
small (250x250 max)
medium (500x500 max)
Large
Extra Large
large ( > 500x500)
Full Resolution
All (PDF)
|
This page
All
|
139
slates, therefore, differ so much from the sandstones, that
there can be no d )ubt. that the orisfin and source, fiom
whet ce they were deiiveo, was different also. They indi-
Ciite a total change in the direction in which the sediment
can)e, .'ind as there is no formation to the northwest, or
southwest, to which their oiigin can be attribnted, 1 am
inclisied to reojard the source as concealed by the present'
ocean
The sandstones in the United States, of the ages closely
approximating to those under consideration, were deposited
ill shallow water. '1 he ripple marks, the foot prints, wvhich
have been preserved, are regarded as proofs of this position.
Taking the same ground and kind of evidence, I have not yet
been able to furnish the same ground of proof for their deposi-tion
in shallow water. I have not yet discovered footprint?, or
ripple marks, and the only f^ict, which goes to support the
view entertnined, of the depth of watev, in which the strata
were deposited, is. a single laver, which had cracked in dry-ing.
These cracks were subsequently filled with sediment.
Still, but few opportunities for a disclosure of the inte-rior
of these deposits have been furnished. The blocks
of sand.-^toiie, which have b^-en employed in b\iildmg,
h;ive been procured from the surface, and which were
alreiidy loosened from their beds; besides this, the strata
hiive not been laid nare by an inundation. The means, there-f(
ire, lor ol)taining a series of facts, bearing upon these
questions, aie ii;snflici( nt. They throw but little light
U[)oii them, and we n)usi, tlierefore, wait until railroads
and intt-rnil iuiprovemenis have 1 id open the series to in-spection.
The evidence, as it now stands, favors the view, that
these rocks were deposited in deep water ; the absence of
all ripple marks, the great thickness d ihe deposits, and
thickness of the deeper layers, indicate for the sandstones
deep oceaaic deposits.
Object Description
Description
| Title | Page 535 |
| Full Text | 139 slates, therefore, differ so much from the sandstones, that there can be no d )ubt. that the orisfin and source, fiom whet ce they were deiiveo, was different also. They indi- Ciite a total change in the direction in which the sediment can)e, .'ind as there is no formation to the northwest, or southwest, to which their oiigin can be attribnted, 1 am inclisied to reojard the source as concealed by the present' ocean The sandstones in the United States, of the ages closely approximating to those under consideration, were deposited ill shallow water. '1 he ripple marks, the foot prints, wvhich have been preserved, are regarded as proofs of this position. Taking the same ground and kind of evidence, I have not yet been able to furnish the same ground of proof for their deposi-tion in shallow water. I have not yet discovered footprint?, or ripple marks, and the only f^ict, which goes to support the view entertnined, of the depth of watev, in which the strata were deposited, is. a single laver, which had cracked in dry-ing. These cracks were subsequently filled with sediment. Still, but few opportunities for a disclosure of the inte-rior of these deposits have been furnished. The blocks of sand.-^toiie, which have b^-en employed in b\iildmg, h;ive been procured from the surface, and which were alreiidy loosened from their beds; besides this, the strata hiive not been laid nare by an inundation. The means, there-f( ire, lor ol)taining a series of facts, bearing upon these questions, aie ii;snflici( nt. They throw but little light U[)oii them, and we n)usi, tlierefore, wait until railroads and intt-rnil iuiprovemenis have 1 id open the series to in-spection. The evidence, as it now stands, favors the view, that these rocks were deposited in deep water ; the absence of all ripple marks, the great thickness d ihe deposits, and thickness of the deeper layers, indicate for the sandstones deep oceaaic deposits. |
