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Fire frequency - this refers to the number of times fire occurs in a given area under a defined geologic time. The concept of fire frequency is often applied to local fire events. [25] Fire intensity - also known as fire severity or magnitude is the degree of fire or the magnitude of fire event. Fire intensity is categorized into low fire ...
The fossil record of fire first appears with the establishment of a land-based flora in the Middle Ordovician period, 9] permitting the accumulation of oxygen in the atmosphere as never before, as the new hordes of land plants pumped it out as a waste product.
By using that method, some areas have tree-ring records dating back a few thousand years. Older wood not connected to a contemporary record can be dated generally with radiocarbon techniques. A tree-ring record can be used to produce information regarding precipitation, temperature, hydrology, and fire corresponding to a particular area.
Tree core sample collected with an increment boarer A cat-face fire scar on a ponderosa pine A cross section of a ponderosa pine fire scar showing several dated fire events The growth record of a tree in seasonal climates is preserved in the growth rings in the stem wood; the field of dendrochronology is the study of the record of climate and ...
The output section of the NFDRS structure chart is the components or simply the outputs that are based in fire behavior description but expressed in the broader context of fire danger rating. [ 6 ] Spread Component – Displays a value numerically equivalent to the predicted forward rate of spread of a head fire in feet per minute.
Fire was an important factor in expanding and developing societies of early hominids. One impact fire might have had was social stratification. The power to make and wield fire may have conferred prestige and social position. [35] Fire also led to a lengthening of daytime activities and allowed more nighttime activities. [45]
In sedimentary rocks, fossils are the only widely applicable tool for time correlation. [1]: 229 Evolution leaves a record of progressive change, sequential and nonrepeating. [1]: 230 A rock unit has a characteristic assemblage of fossils, independent of its lithology.
In the stratigraphy sub-discipline of geology, a Global Standard Stratigraphic Age, abbreviated GSSA, is a chronological reference point and criterion in the geologic record used to define the boundaries (an internationally sanctioned benchmark point) between different geological periods, epochs or ages on the overall geologic time scale in a chronostratigraphically useful rock layer.