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Space science has been called “the collection of scientific problems to which space vehicles can make some specific contributions not achievable by ground-based experiments.” Geography, the most spatial of the sciences, has now been marked as one of these “space sciences.” The National Aeronautics and Space Administration (NASA) is sponsoring...

The United States Geological Survey was established by Congress in 1879 to make a systematic study of the geology and natural resources of the United States. To provide the essential base maps for these studies, the Survey immediately began a program of topographic mapping. In 1882 a general plan was adopted for a standard series...

No abstract available....

The surface-water records for the 1964 water year for gaging stations, partial-record stations, and miscellaneous sites within the State of Indiana are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The records were collected and computed by the...

No abstract available....

The compression of peat beneath its own weight (autocompaction) is discussed, and it is shown that because of this process radiocarbondated samples of salt-marsh peat or peaty sediment, other than very thin samples cut from the base of the deposit, cannot be correlated with sea level without construction of a...

Pebbles of silicified gymnospermous wood occur widely in the drift of southeastern Massachusetts. An investigation of the distribution of these pebbles shows the bedrock source of the wood to be tuffaceous beds that apparently overlie older granite in the Middleboro-Plympton area, Massachusetts, and are at the base of the Carboniferous...

No abstract available....

An unusually well-preserved Ordovician fossil from Czechoslovakia shows that the enigmatic paired structures once thought to be outgrowths of the operculum of Hyolithes are really independent structures lying between the operculum and the aperture of the shell. The find seems to provide conclusive proof of the morphologic uniqueness of hyolithids....

No abstract available. ...

White County is in the Northeast Georgia Highland. It comprises 243 square miles and has abouit 7,000 Inhabitants. The county seat is Cleveland.Although the scene of considerable mining activity in the past, White County now has few operating mines: a small production of clay1 for the manufacture of miscellaneous potter...

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This study shows that aeromagnetic anomalies of less than 200 gammas are associated with topographic relief of exposed Precambrian granitic and volcanic rocks of the St. François Mountains. Anomalies resulting from hills coarsely crystalline granite are as high as 100 gammas in amplitude, whereas anomalies over comparable hills of fine-grained rocks, such as granophyre or devitrified volcanic rock, are...

Podiform chromite deposits occur in alpine peridotite and mafic complexes and fundamentally are tabular, pencil-shaped, or irregular in form. The chromite characteristically is anhedral and commonly shows effects of granulation and magmatic corrosion. Flow-layering, foliation, and lineation are parallel in most chromite deposits and peridotite host rocks, and normally pass through major...

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A Czechoslovakian tektite or moldavite shows clear, indirect evidence of aerodynamic ablation. This large tektite has the shape of a teardrop, with a strongly convex, deeply corroded, but clearly identifiable front and a planoconvex, relatively smooth, posterior surface. In spite of much erosion and corrosion, demarcation of the posterior and...

An uneven erosion surface separates calcareous sedimentary rocks above and vesicular andesite porphyry below at the Guayacan mine of central Chile. Channel-like depressions filled with sedimentary rock flank elongate, stratiform bodies of disseminated copper ore which impregnate the vesicular crests of andesite lava flows. The "channels" lie parallel to and mark the margins of tongues of lava. Erosional features...

No abstract available. ...

The iron ores of Minas Gerais, Brazil, fall into two categories: (1) hypogene hematite ore averaging 66 percent or more Fe, and (2) lower-grade supergene ores. Most ore now extracted is high-grade hypogene ore; lower-grade supergene ores will be of much future value. All supergene ores formed by weathering of itabirite, a metamorphosed oxide-facies iron formation averaging about 38 percent Fe and 44 percent Si02. The Caue Itabirite crops out for...

“Hidden recharge” is defined as subsurface percolation of water from basin‐margin mountains directly into aquifers of the valley basins. It is an important, and sometimes neglected, item in hydrologic equations. Locally, geologic conditions permit inter‐basin circulation of ground water. The concept that ground‐water basins necessarily terminate at the contact between...

The typical volcanic rocks of most island arcs and eugeosynclines, and of some continental environments, are basalt, andesite, and dacite, of high alumina content. The high-alumina basalt differs from tholeiitic basalt primarily in having a greater content of the components of calcic plagioclase. Laboratory data indicate that in the upper...