This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 Excerpt: ...effect of rain water running over the surface. GILBERT 1 DUST BROUGHT BY THE WIND. 27 So by streams, lakes, and winds there was spread a great mantle of sand and silt, by which the minor valleys and hills were buried from sight and the Cretaceous formations were at the same time concealed. Eventually deposition was in ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 Excerpt: ...effect of rain water running over the surface. GILBERT 1 DUST BROUGHT BY THE WIND. 27 So by streams, lakes, and winds there was spread a great mantle of sand and silt, by which the minor valleys and hills were buried from sight and the Cretaceous formations were at the same time concealed. Eventually deposition was in turn arrested and erosion resumed. The streams, which had been shifted from one course to another so as to occupy successively and many times each part of the surface, became fixed in position as soon as changing conditions caused their waters to erode once more. The cause of the new change was probably renewed uplift--a general elevation of the plains region, which was greater at the west than at the east, so that the eastward slopes were increased. Streams flowiug in that direction acquired a greater velocity, and were able not only to carry forward all the detritus with which the storms fed them, but also to wear their beds and deepen their channels. As the stream channels were worn slowly down the earth of adjacent slopes was washed into them, and thus broad valleys were opened out. Then from the uplands between the valleys more or less of the sandy formation was washed down, so as to form a coating over the slopes of the valley. As the material occupying the slopes is identical in character with the great deposit whence it was derived, it is now hard to distinguish them, and the name '"upland sands and gravels" is applied alike to the original and the derivative deposits. At a later epoch the land was lifted still higher and erosion greatly accelerated, so that the stream valleys were deepened several hundred feet without being opened so broadly as before. This later action gave somewhat definite limits to the upland formation, ...
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Seller's Description:
*Price HAS BEEN REDUCED by 10% until Monday, Nov. 11 (sale item)* 51 pp., 13 plates, original paper wrappers, covers darkened and tattered, minor notes and handstamps, good only. -If you are reading this, this item is actually (physically) in our stock and ready for shipment once ordered. We are not bookjackers. Buyer is responsible for any additional duties, taxes, or fees required by recipient's country.
Choose your shipping method in Checkout. Costs may vary based on destination.
Seller's Description:
*Price HAS BEEN REDUCED by 10% until Monday, Nov. 11 (sale item)* quarto, 51 pp. 13 plates, original softcovers, reprinted from USGS Annual Report, 17th, fair, . -If you are reading this, this item is actually (physically) in our stock and ready for shipment once ordered. We are not bookjackers. Buyer is responsible for any additional duties, taxes, or fees required by recipient's country.
