Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “tectonics”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,135 records · Page 63

Concerning the meteoritic origin of the Puchezh-Katunki crater

Criticism of the works of Vardaniants (1961) and Goretskii (1962) regarding the origin of the Puchezh-Katunki crater, and development of a new hypothesis regarding this disturbance. Although Vardaniants defines the Puchezh-Katunki disturbance as a structure of explosive nature and assumes that the explosion originated as a consequence of accumulation of gases in the crystalline basement of the Russian platform, he lacks evidence to qualify this explosion as coming from a depth. Goretskii's tectonic-injection hypothesis attributes the formation of the disturbance to penetration of an intrusion of basic and ultrabasic rocks into the Paleozoic rocks of the platform. It is shown that, even if the intrusion were spread somewhere at depth, it could not account for the extent of the deformation in the disturbance. It is suggested that this disturbance is of meteoritic origin, since the structure and morphology of the region are similar to the sloping conical surface produced by an explosive meteor crater. The energy, mass, and size of the asteroid which could cause such a disturbance are estimated, and it is shown that the probability of the occurrence of an impact of this size is finite over geological time.

Firsov, L.↗

Analysis of lunar mare geology from Apollo photography

Panoramic and metric photography of the lunar surface from Apollo missions 15, 16, and 17 is the basis for descriptions and interpretations of mare surface features. It is suggested that the formation of mare ridges occurred over an extended period of time rather than in single short episodes of activity through faulting, flexuring, volcanism, and plutonism. Spatial relationships between rilles and ridges suggest they were formed both simultaneously and sequentially. The sinuous rilles may have developed as open lava channels or collapsed lava tubes, while the straight rilles may have been formed by fracturing. It is inferred that small scale volcanism and tectonism have occurred between major flooding episodes.

Young, R. A.↗

Observations of Mare Serenitatis from lunar orbit and their interpretation

Visual observations of color differences of Serenitatis mare materials from orbit complement photography and other remotely sensed data. The light tan gray inner fill of the Serenitatis Basin is younger than the dark blue gray annulus; the latter continues into and appears to be contemporaneous with the fill of Mare Tranquillitatis. Mare ridges occur in both the inner basin fill and the dark annulus of Serenitatis. Ridges are interpreted as the result of structural deformation and up-doming after the solidification of the basaltic lavas. On the southeastern rim of the Serenitatis Basin is the darkest blue gray unit within which Apollo 17 landed. Highland massifs surrounding this unit have unstable slopes which are believed to be the result of localized tectonic activity. On the southwest rim of the basin are the dark tan to brown gray mantling materials of the Sulpicius Gallus Formation.

El-Baz, F.↗

Geophysical data and the interior of the moon

Geophysical data and physical properties of the lunar interior are considered, giving attention to density, gravity field, viscosity, the strength of lunar materials, electrical conductivity, and magnetic properties. Seismic data and structure of the lunar interior are discussed, taking into account moonquakes and lunar tectonism, the velocity structure, and the compositional implications of the velocity structure. Questions regarding the thermal state and the evolution of the moon are also explored. The data and the models presented characterize the moon as a differentiated body which evolved relatively early in its history.

Toksoz, M. N.↗

Geologic uses and non-uses of ERTS-1 - Northern Rocky Mountains and similar areas

Using prints of ERTS-1 multispectral scanner imagery a large area of varied geology and vegetative cover was studied, utilizing the classic methods of photogeology generally applied to conventional aerial photographs. The study area was mainly the western half of Montana, but extension of tectonic annotations to the west resulted in coverage of most of the northern Rocky Mountains, as well as the plains to the east. The northern Rocky Mountains are exceptionally suitable for a feasibility study because they contain a wide range of geologic styles exposed under varying conditions of plant and soil cover. The basic approach was to study the satellite imagery visually, applying background knowledge of regional geology and experience with conventional aerial photographs.

Weidman, R. M.↗

Geologic evaluation and applications of ERTS-1 imagery over Georgia

Satellite imagery and other remote sensing tools and techniques have provided a powerful tool to assist geologic research; significantly increased the mapping efficiency of field geologists; shown new lineaments associated with known shear and fault zones; delineated new structural features; provided a tool to reevaluate tectonic history; helped to locate potential ground-water sources and areas of aquifer recharge; defined areas of geologic hazards; shown areas of heavy siltation in major reservoirs; and, by close interval repetition, aided in monitoring surface mine reclamation activities and the environmental protection of the intricate marshland system. The Georgia Geological Survey has been engaged in regional mapping for the new state geologic map. ERTS-1 images enlarged to compatible mapping scales have increased field geologic mapping efficiency by at least 25%. There are a number of areas where data from ERTS-1 imagery has allowed a notably higher level of precision than has been available with any amount of field work on the ground.

Pickering, S. M.↗

Earth and ocean physics

A procedure for obtaining a parameterization of the marine geoid for suitable orthogonality properties in altimetry data is discussed. The application of the technique to the Puerto Rico trench is explained and a map of the data is developed. The Goddard Earth Model (GEM-6) is described to show the method for determining the earth gravity field using data obtained from satellite tracking stations. The derivation of a global ocean tide model from satellite data is explained. The influence of solid earth and ocean tides on the inclination of GEOS-1 is plotted. The delineation of the geographical fracture pattern and boundary system of the tectonic plates using ERTS satellite is shown.

Source record↗

Investigation of lineaments on Skylab and ERTS images of Peninsular Ranges, Southwestern California

The author has identified the following significant results. Northwest trending faults such as the Elsinore and San Jacinto are prominently displayed on Skylab and ERTS images of the Peninsular Ranges, southern California. Northeast, north-south, and west-north-west trending lineaments and faults are also apparent on satellite imagery. Several of the lineaments represent previously unmapped faults. Other lineaments are due to erosion along foliation directions and sharp bends in basement rock contacts rather than faulting. The northeast trending Thing Valley fault appears to be offset by the south branch of the Elsinore fault near Agua Caliente Hot Springs. Larger horizontal displacement along the Elsinore fault further northwest may be distributed along several faults which branch from the Elsinore fault in the Peninsular Ranges. The northeast and west-northwest trending faults are truncated by the major northwest trending faults and appear to be restricted to basement terrane. Limited data on displacement direction suggests that the northeast and west-northwest trending faults formed in response to an earlier period of east-northeast, west-southwest crustal shortening. Such a stress system is consistent with the plate tectonic model of a subduction zone parallel to the continental margin suggested in the late Mesozoic and early Tertiary.

Merifield, P. M.↗

The Colorado School of Mines Nevada geothermal study

Geothermal systems in the Basin and Range Province of the western United States probably differ in many respects from geothermal systems already discovered in other parts of the world because of the unique tectonic setting. To investigate this, a study of the geothermal occurrences at Fly Ranch, approximately 100 miles north of Reno, Nevada, has been undertaken. Ample evidence for a geothermal system exists in this area, including the surface expression of heat flow in the form of hot springs, an extensive area of low electrical resistivity, and a high level of seismicity along faults bounding the thermal area. However, geophysical and geological studies have not yet provided evidence for a local heat source at depth. Additional detailed geophysical and geological studies, as well as drilling, must be completed before the geothermal system can be described fully.

Keller, G. V.↗

Measuring ground movement in geothermal areas of Imperial Valley, California

Significant ground movement may accompany the extraction of large quantities of fluids from the subsurface. In Imperial Valley, California, one of the potential hazards of geothermal development is the threat of both subsidence and horizontal movement of the land surface. Regional and local survey nets are being monitored to detect and measure possible ground movement caused by future geothermal developments. Precise measurement of surface and subsurface changes will be required to differentiate man-induced changes from natural processes in this tectonically active region.

Lofgren, B. E.↗

Geological study of the southern part of the Malagasy republic using ERTS orbital images

The author has identified the following significant results. The Malagasy stratigraphy and tectonic are very complex, but the results obtained using ERTS-1 images interpretation make credible some hypothesis recently proposed by geologists. Most of known fractures are identified and numerous new observations are made on these images in the field of linear fractures. Some of them extend or relay known fractures and many others are totally new even if scattered field observations make it possible to assume that they correspond to reality. In the domain of lithology different types of rocks are distinguished, but the results are better in sedimentary formations than in the basement.

Weecksteen, G.↗

Lunakhod-2: Preliminary research results

Results from the Lunakhod 2 experiment on the surface property variations and relief structure of lunar craters are presented. Tectonic fractures, iron composition of lunar rocks, magnetic measurements, lunar sky brightness, and corpuscular radiation of the lunar body were studied.

Vinogradov, A. P.↗

Analysis of ERTS-1 imagery of Wyoming and its application to evaluation of Wyoming's natural resources

The author has identified the following significant results. The Earth Resources Technology Satellite data included the following successful applications: (1) general geologic mapping, (2) structural and tectonic studies, (3) landforms and surface processes, (4) mineral exploration, (5) land use inventories, (6) hydrologic studies, (7) investigations in agriculture and forestry, and (8) environmental quality and ecology. The chief advantages of ERTS-1 data for geologic studies are synoptic view, spectral information, and seasonal coverage. The spectral data and repetitive aspect are also important for land use and vegetation studies. Low resolution and lack of steoscopic coverage were found to be the main limitations of ERTS data.

Houston, R. S.↗

Mapping of lithologic and structural units using multispectral imagery

The author has identified the following significant results. ERTS-1 MSS imagery covering the Afar-Triangle/Ethiopia and adjacent regions (Ethiopian Plateau, Somali Plateau, and parts of Yemen and Saudi Arabi) was applied to the mapping of lithologic and structural units of the test area at a scale 1:1,000,000. Results of the geological evaluation of the ERTS-1 imagery of the Afar have proven the usefullness of this type of satellite data for regional geological mapping. Evaluation of the ERTS images also resulted in new aspects of the structural setting and tectonic development of the Afar-Triangle, where three large rift systems, the oceanic rifts of the Red Sea and Gulf of Aden and the continental East African rift system, seem to meet each other. Surface structures mapped by ERTS do not indicate that the oceanic rift of the Gulf of Aden (Sheba Ridge) continues into the area of continental crust west of the Gulf of Tadjura. ERTS data show that the Wonji fault belt of the African rift system does not enter or cut through the central Afar. The Aysha-Horst is not a Horst but an autochthonous spur of the Somali Plateau.

Kronberg, P.↗

Multidisciplinary geoscientific experiments in central Europe

The author has identified the following significant results. Studies were carried out in the fields of geology-pedology, coastal dynamics, geodesy-cartography, geography, and data processing. In geology-pedology, a comparison of ERTS image studies with extensive ground data led to a better understanding of the relationship between vegetation, soil, bedrock, and other geologic features. Findings in linear tectonics gave better insight in orogeny and ore deposit development for prospecting. Coastal studies proved the value of ERTS images for the updating of nautical charts, as well as small scale topographic maps. A plotter for large scale high speed image generation from CCT was developed.

Bannert, D.↗

A summary of ERTS data applications in Alaska

ERTS has proven to be an exceedingly useful tool for the preparation of urgently needed resource surveys in Alaska. For this reason the wide utilization of ERTS data by federal, state and industrial agencies in Alaska is increasingly directed toward the solution of operational problems in resource inventories, environmental surveys, and land use planning. Examples of some applications are discussed in connection with surveys of potential agricultural lands; mapping of predicted archaeological sites; permafrost terrain and aufeis mapping; snow melt enhancement from Prudhoe Bay roads; geologic interpretations correlated ith possible new petroleum fields, with earthquake activity, and with plate tectonic motion along the Denali fault system; hydrology in monitoring surging glaciers and the break-up characteristics of the Chena River watershed; sea-ice morphology correlated with marine mammal distribution; and coastal sediment plume circulation patterns.

Miller, J. M.↗

Origin of Martian channels - Clathrates and water

Criticism is directed at the suggestion that Martian channels may have been eroded by liquid water produced by the depressurization of CO2 hydrate. The release of pre-existing subsurface liquid water, such as that trapped under a permafrost layer, by meteorite impact or tectonic activity could produce sufficient flow and would not require heat transfer. The presence of water in a CO2 hydrate is shown to be detrimental to its release from an underground reservoir.

Peale, S. J.↗

Absolute plate motions by boundary velocity minimizations

The main interaction of the earth's interior with the lithosphere is as a material source and sink. An absolute reference frame defined by minimizing the translational motion of tectonic plate boundaries differs by 0.6 cm/year from a frame defined by hot spot traces and by 0.4 cm/year from the frame defined by the most plausible model of drag forces on the plates. The rms absolute translational velocities are about 2 cm/year for ocean-ocean plate boundaries and 1.5 cm/year for ocean-continent plate boundaries. The close agreement between the source and sink and the drag-dependent definitions suggests that the lithosphere, as a stress guide, to some extent controls the locations of its sources and sinks.

Kaula, W. M.↗