Image
from article Continental drift
Map of the Earth as Pangea broke up as a result of continental drift. (Copyright © McGraw-Hill)
Search Results
Search Results
Refine this search
Search result paging links
3,177 results
Image
from article Computer virus
Some viruses are more destructive than others, causing devastation or theft of data. (Credit: iStockphoto.com/Zmeel Photography)
Image
from article Computer virus
Purposes for creating viruses.
Image
from article Computer virus
Daily virus threats experienced by large organizations.
Image
from article Computer virus
Examples of vulnerabilities to computer viruses.
Image
from article Computer programming
Program code. (Credit: Max Delson Martins Santos/Getty Images)
Image
from article Stalactites and stalagmites
Stalactite and stalagmite deposits. Along the central opening are deposits made by water as it dripped from the crack in the limestone. Outside layers were deposited by water flowing over the surface. Water may drip to the floor and create a…
Image
from article Teleconferencing
A typical teleconference. (Courtesy of Lifesize, www.lifesize.com)
Image
from article Lake
MODIS (MODerate-resolution Imaging Spectroradiometer) Terra satellite image of the Great Lakes, September 15, 2015. (Credit: NOAA Great Lakes CoastWatch)
Image
from article Lake
Oxbows in Bolivia. Landsat satellite image of the Beni River in Bolivia, which resembles a blue ribbon as it flows toward the Amazon River. Scattered along the river are numerous oxbow lakes, which are curved bodies of water that form when a meander…
Image
from article Oil shale
Image
from article Oil shale
C-13 nuclear magnetic resonance characterization of organic matter in two United States oil shale samples. (a) Colorado oil shale, 80% aliphatic carbon content with 69% conversion of organic carbon to oil. (b) Kentucky oil shale, 52% aliphatic…
Image
from article Oil shale
Oil shale deposits of the United States. (Courtesy of John Ward Smith)
Image
from article Oil shale
Oil shale retorting systems: (a) internally heated, (b) externally heated.
Image
from article Hydrothermal vent
Black smoker plume at a hydrothermal vent. Black smoker vents are distinguished by the presence of such large quantities of minute mineral particles that the plumes become virtually opaque. The minerals solidify as they cool, forming chimney-like…
Image
from article Hydrothermal vent
Schematic view of the seawater circulation system creating hydrothermal vents along a mid-oceanic ridge.
Image
from article Hydrothermal vent
Giant Riftia tubeworms from warm vents at the Galápagos Rift vent site. These tubeworms reach lengths of at least 2 m (6 ft).
Image
from article Dendrochronology
Ring patterns showing complacent and sensitive ring series. (a) Climate has minimal effect on ring widths when trees have ample moisture every year. (b) Maximum ring-width variations occur on sites where growth is limited by factors that vary from…
Image
from article Dendrochronology
Core being taken from a tree with an increment borer. (Courtesy of Laboratory of Tree-Ring Research, University of Arizona)
Image
from article Dendrochronology
Chronology building. Chronologies are extended backward in time by matching patterns of wood samples whose ages overlap.
Image
from article Dendrochronology
Skeleton plot (top) from an idealized tree-ring sequence in a specimen (bottom). Ring widths are represented by vertical lines in inverse proportion; that is, tall lines represent narrow rings. An exceptionally wide ring is designated by the letter…
Image
from article Dendrochronology
Bristlecone pines, which attain ages of more than 4000 years, form the basis for the second longest chronology yet developed. (Courtesy of Laboratory of Tree-Ring Research, University of Arizona)
Image
from article Global climate change
Fossil-fuel-burning power plant—a source of greenhouse-gas emissions. (Credit: Schroptschop/Getty Images)
Image
from article Global climate change
Climate models run with natural factors alone (for example, solar and volcanic activity) fail to produce results that align with observations. The top left panel shows annual global average surface temperature anomalies (the difference between the…
Image
from article Global climate change
Atmospheric concentrations of carbon dioxide (CO2) in parts per million (ppm) (top panel), methane (CH4) in parts per billion (ppb) (middle panel), and nitrous oxide (N2O) in parts per billion (ppb) (bottom panel) over the past 800,000 years (left…
Image
from article Global climate change
Annual global average surface temperature anomalies (difference between the annual value and the 1951–1980 average) in degrees Celsius over the period from 1880 to 2017. (Data source: NASA/GISS, 2018)
Image
from article Global climate change
Contributions to observed global average surface temperature change (black bar) over the period 1951–2010 in degrees Celsius. Green bar: greenhouse-gas emissions. Yellow bar: other human-caused drivers (including aerosol emissions and…
Image
from article Dacite
Photomicrograph of a dacite from the Zitacuaro– Valle de Bravo region of central Mexico. P = plagioclase, O = orthopyroxene (hypersthene), A = augite, G = glassy groundmass.
Image
from article Dacite
Dacite domes from the Zitacuaro volcanic complex of central Mexico. (Photo by D. Blatter)
Image
from article Perthite
Schematic showing the development of two perthitic intergrowth textures. (After G. W. Lorimer and P. E. Champness, The origin of the phase distribution in two perthitic alkali feldspars, Philos. Mag., 28:1401, 1973)
Image
from article WiMAX broadband wireless communications
Fixed and mobile WiMAX services.
Image
from article WiMAX broadband wireless communications
WiMAX Advanced Antenna Systems (AAS) using multiple-input techniques. (a) Increased robustness using multiple input–single output (MISO). (b) Increased capacity using multiple input–multiple output (MIMO).
Image
from article Touch-screen display
Doctor using a touch-screen tablet. (Credit: John Lamb/Getty Images)
Image
from article Touch-screen display
Capacitive touch sensor. (a) A single electrode is brought to a potential +V, and the resulting charge accumulated is recorded and determines the capacitance of the electrode. (b) The electrode is still held at potential +V, but because of the…
Image
from article Touch-screen display
In mutual capacitance sensing, two electrodes are used. The potential difference between them is changed by a small amount dV, and the resulting change of charge on one of them is examined. In the presence of a finger, this amount of charge differs,…
Image
from article Touch-screen display
Optical-over-the-display method. (a) Two cameras are inspecting the surface parallel to the display, while 18 light sources are distributed around the edges. Each camera in this specific scenario has a view of 12 of the light sources. (b) Once a…
Image
from article Touch-screen display
Optical-in-the-display method. Looking through a cross section of the cover glass on the display, we see one light source launching light into the glass, which serves as a waveguide. When the finger touches the glass, some of the light leaks…
Image
from article Touch-screen display
Resistive method. (a) Cross section of typical resistive sensor. Two conductive layers are laminated on transparent material (glass, clear plastic, or a similar material), and are kept with a small space between them (usually about 40 μm). (b)…
Image
from article Salt dome
Salt domes and related structures; the overlying and surrounding sediments have been removed for clarity.
Image
from article Salt dome
Three modes of salt diapirism and their characteristic structures. (a) Reactive piercement. (b) Active piercement. (c) Passive piercement.
Image
from article Limestone
Surface of a Lower Cretaceous limestone exposed in a quarry just north of Austin, Texas. The limestone is composed predominantly of fossil fragments. The large ribbed fossils are Trigonia sp., a common Cretaceous mollusk. This limestone is used…
Image
from article Limestone
Schematic rendering of a reef illustrating the complex interaction of biologic framework growth, sedimentation, and chemical precipitation in the formation of reef limestones. (After R. N. Ginsberg and H. A. Lowenstam, The influence of marine bottom…
Image
from article Limestone
Image
from article Diapir
Vertical sections showing diapirism by (a) ductile folding of cover and (b) faulting of cover. Number 1 indicates the bedding of the diapir, and 2–5 identify cover layers.
Image
from article Biosphere
All environments capable of sustaining life above, on, and beneath the Earth's surface, as well as in the oceans, are contained in the biosphere. (Credit: National Aeronautics and Space Administration)
Image
from article Biosphere
The upper and lower limits of the biosphere are not sharply defined. However, most of the biosphere lies within the zone that is reached by sunlight and where liquid water exists. The mountains shown in this photograph are located in Torres del…
Image
from article Carboniferous
Carboniferous, the fifth period of the Paleozoic Era.
Image
from article Carboniferous
Development of stratigraphic nomenclature for the Carboniferous.
Image
from article Carboniferous
Curves outlining the fluctuations of sea level during the Carboniferous. The Mississippian sea-level curve is typical of times when glaciation was not a major factor in controlling sea levels, and the Pennsylvanian sea-level curve is characteristic…
Image
from article Carboniferous
Paleogeography of the Carboniferous. (a) Early Carboniferous (Mississippian) Tournaisian and Visean epochs, with a major east-west equatorial seaway between Euramerica and Gondwana. (b) Late Carboniferous (Pennsylvanian) Moscovian (or Desmoinesian)…
