Age of the Grand Canyon Everyone has heard about the great ages claimed by proponents of evolution, this is particularly true of Grand Canyon. The question is, do radioactive isotope dating methods provide convincing scientific evidence for billion-year old rocks? Two lava-flow formations occur in the Grand Canyon: In a recent study, these formations were both selected for radioactive isotope dating by the rubidium-strontium isochron technique. The deeply buried Cardenas Basalt occurs among the oldest strata of the Grand Canyon. This basalt has been assigned to the Precambrian strata of the Unkar Group, which contains the lowest, and hence the oldest strata of the Grand Canyon.
List of places with columnar basalt During the cooling of a thick lava flow, contractional joints or fractures form. While a flow can shrink in the vertical dimension without fracturing, it can’t easily accommodate shrinking in the horizontal direction unless cracks form; the extensive fracture network that develops results in the formation of columns. The topology of the lateral shapes of these columns can broadly be classed as a random cellular network.
These structures are predominantly hexagonal in cross-section, but polygons with three to twelve or more sides can be observed. Submarine eruptions Pillow basalts on the south Pacific seafloor Outcrop of a pillow basalt, Italy Pillow basalts Main article: Pillow lava When basalt erupts underwater or flows into the sea, contact with the water quenches the surface and the lava forms a distinctive pillow shape, through which the hot lava breaks to form another pillow.
Since the rapid rise to dominance of the plume-head/plume-tail model for flood basalts (Richards et al., ; Campbell & Griffiths, ), hundreds of papers have invoked, or supported, a plume head origin for the Deccan Traps of India.
Mesosiderites Iron meteorites 5. The most common meteorites are chondrites, which are stony meteorites. Radiometric dating of chondrites has placed them at the age of 4. They are considered pristine samples of early solar system matter, although in many cases their properties have been modified by thermal metamorphism or icy alteration.
Some meteoriticists have suggested that the different properties found in various chondrites suggest the location in which they were formed. Enstatite chondrites contain the most refractory elements and are believed to have formed in the inner solar system.
How Old Is the Earth?
These are K-Ar data obtained on glauconite, a potassium-bearing clay mineral that forms in some marine sediment. Woodmorappe fails to mention, however, that these data were obtained as part of a controlled experiment to test, on samples of known age, the applicability of the K-Ar method to glauconite and to illite, another clay mineral. He also neglects to mention that most of the 89 K-Ar ages reported in their study agree very well with the expected ages.
Before the Ice Age that began about 35, years ago, there had been about 95, years (95, years is approximately one long Milankovitch cycle of variation of eccentricity of the Earth’s orbit) of mild climate since the end of the preceding Ice Age about , years ago.
How accurate are carbon-dating methods? All methods of radioactive dating rely on three assumptions that may not necessarily be true: Rate of Decay It is assumed that the rate of decay has remained constant over time. This assumption is backed by numerous scientific studies and is relatively sound. However, conditions may have been different in the past and could have influenced the rate of decay or formation of radioactive elements.
Evolutionists assume that the rate of cosmic bombardment of the atmosphere has always remained constant and that the rate of decay has remained constant. Thus radioactive dating relies purely on assumptions. We could put forward the following counter arguments to the constancy of these assumptions: The current high rate of entry might be a consequence of a disturbed post-Flood environment that altered the carbon to carbon ratio.
Pre-Flood dates would thus have to be discarded. Some scientists argue that the magnetic field of the earth has declined over time. Carbon comes from nitrogen and is independent of the carbon reservoir. If even a small percentage of the limestone deposits were still in the form of living marine organisms at the time of the Flood, then the small amount of carbon would have mixed with a much larger carbon reservoir, thus resulting in a drastically reduced ratio.
As the molten rock came to the surface, the Earth’s crust gradually sank into the space left by the rising lava. This subsidence of the crust produced a large, slightly depressed lava plain now known as the Columbia Basin or Columbia River Plateau. The northwesterly advancing lava forced the ancient Columbia River into its present course.
Discovery and Characteristics. The Venus of Berekhat Ram was found by archeologist N. Goren-Inbar (Hebrew University of Jerusalem) during archeological excavations on the Golan Heights between Syria and Israel during the summer of
A well-documented stratigraphy indicates at least GRB flow fields or individual eruptions , and on this basis suggests an average inter-eruption hiatus of less than years. Isotopic age-dating cannot resolve time gaps between GRB eruptions, and it is difficult to otherwise form a picture of the durations of eruptions because of non-uniform weathering in the top of flow fields and a general paucity of sediments between GR lavas. Where sediment has formed on top of GRB lavas, it varies in thickness from zero to cm of silty to fine-sandy material, with occasional diatomaceous sediment.
Individual GRB eruptions varied considerably in volume but many were greater than km 3 in size. Recent improvements in age-dating for other continental flood basalt CFB lava sequences have yielded estimates of total eruptive durations of less than 1 My for high-volume pulses of lava production. The GRB appears to be a similar example, where the main pulse occupied a brief period.
Even allowing for moderate to long-duration pahoehoe flow field production, the amount of time the system spends in active lava-producing mode is small less than c.
Is carbon-14 dating accurate? (read the whole article or dont answer)?
It consists of complexly interbedded, thin, and discontinuous beds of basalt , hyaloclastite , and sandstone. The lava within this unit consists of pahoehoe lava flows of olivine -rich basalt. Within the lower part of the Cardenas Basalt, the lava is highly altered and might have been glassy at one time. Near the top of the lower unit the basalt is more massive and less altered.
Most people accept the current old-earth (OE) age estimate of around billion years. This age is obtained from radiometric dating and is assumed by evolutionists to provide a sufficiently long time-frame for Darwinian evolution.
Copyright remains with the author s or their institution s. Permission for reuse free in most cases can be obtained from RightsLink. Paper handled by Associate Editor Brendan Murphy. Published on the web 22 November Canadian Journal of Earth Sciences, , 54 4: One sample of medium-grained basalt yielded a plateau age of A second sample of zeolite-bearing basalt yielded a discordant age spectrum and a younger age of ca.
Whole-rock chemical data show that the Ashfield Formation basalt is low-Ti continental tholeiite, consistent with its within-plate tectonic setting. The age and geochemical data from the Ashfield Formation provide the first evidence for early Mesozoic CAMP volcanism in Cape Breton Island and demonstrate that the event was more widespread in Nova Scotia than previously thought, which has implications for its continuity and extent elsewhere within CAMP.
How deep do common basaltic magmas form and differentiate? Journal of Geophysical Research Armstrong RL, Besancon J. A Triassic time-scale dilemma:
Hiesinger (2011) Nearside Mare Age Units Shapefile
Basalt commonly features a very fine-grained or glassy matrix interspersed with visible mineral grains. The average density is 3. Basalt is defined by its mineral content and texture , and physical descriptions without mineralogical context may be unreliable in some circumstances. Basalt is usually grey to black in colour, but rapidly weathers to brown or rust-red due to oxidation of its mafic iron-rich minerals into hematite and other iron oxides and hydroxides. Although usually characterized as “dark”, basaltic rocks exhibit a wide range of shading due to regional geochemical processes.
Due to weathering or high concentrations of plagioclase, some basalts can be quite light-coloured, superficially resembling andesite to untrained eyes.
The age of most of the artifacts at this site has not yet been conclusively determined, but their quantity, consistency of form, distinctive carving marks, and representation of bird and shaman-like hybrid bird-human images indicate that they are of human manufacture. Several spirally fractured deer bones have been unearthed, indicating human activity.
I have just completed the data reduction on a low potassium basalt from the Medicine Lake, California, the basalt of Tionesta. The recent development of small volume low-background noble gas extraction systems and low-background high-sensitivity mass spectrometers have improved our ability to more accurately and precisely date geologic events. However, the dating of Quaternary, low potassium rocks continues to test the limits of the method because of small quantities of radiogenic argon and large atmospheric argon contamination.
In these early studies the vertical succession of sedimentary rocks and structures were used to date geologic units and events relatively. In addition, faunal succession and the use of “key” diagnostic fossils were used to correlate lithologic units over wide geographic areas. Although lithologic units could be placed within a known sequence of geologic periods of roughly similar age, absolute ages, expressed in units of years, could not be assigned.
Until the twentieth century geologists were limited to these relative dating methods. For a complete discussion on the development of the Geologic time scale see Berry, Following the discovery of radioactivity by Becquerel a,b,c near the end of the nineteenth century, the possibility of using this phenomenon as a means for determining the age of uranium-bearing minerals was demonstrated by Rutherford In his study Rutherford measured the U and He He is an intermediate decay product of U contents of uranium-bearing minerals to calculate an age.
One year later Boltwood developed the chemical U-Pb method.
Lawrence Berkeley National Laboratory
Click here to download a PDF version of this webpage Summary The widely accepted mantle plume model e. Geological and geophysical data from the Deccan provide no support for the plume model and arguably undermine it altogether Sheth, a ,b. The interplay of several intersecting continental rift zones in India is apparently responsible for the roughly circular outcrop of the Deccan.
Radiometric dating or radioactive dating is a technique used to date materials such as rocks or carbon, in which trace radioactive impurities were selectively incorporated when they were formed. The method compares the abundance of a naturally occurring radioactive isotope within the material to the abundance of its decay products, which form at a known constant rate of decay.
Outlook Other Abstract U-Pb radioisotope dating is now the absolute dating method of first choice among geochronologists, especially using the mineral zircon. A variety of analytical instruments have also now been developed using different micro-sampling techniques coupled with mass spectrometers, thus enabling wide usage of U-Pb radioisotope dating. However, problems remain in the interpretation of the measured Pb isotopic ratios to transform them into ages.
Among them is the presence of non-radiogenic Pb of unknown composition, often referred to as common or initial Pb. There is also primordial Pb that the earth acquired when it formed, its isotopic composition determined as that of troilite in the Canyon Diablo iron meteorite. Subsequently new crustal rocks formed via partial melts from the mantle.
So the Pb isotope ratios measured in these rocks today must be interpreted before their U-Pb ages can be calculated. Various methods have been devised to determine this initial or common Pb, but all involve making unprovable assumptions. Zircon does incorporate initial Pb when it crystallizes. The amount of Pb cannot be measured independently and accurately. It cannot be demonstrated that the initial Pb only consisted of Pb atoms. It cannot be proven that the Pb in apparently cogenetic U- or Th-free minerals is only initial Pb, and that it is identical to the initial Pb in the mineral being dated.