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Volcanoes of the World; Volcano Basic Data
Table of
Contents
IDENTIFICATION_INFORMATION
Citation:
Citation_Information:
Originator: Smithsonian Institution, Global Volcanism Program
Publication_Date: 1995
Title: Volcanoes of the World; Volcano Basic Data
Edition:
Geospatial_Data_Presentation_Form: Map
Publication_Information:
Publication_Place:
Publisher:
Other_Citation_Details:
Online_Linkage: HTTP://www.volcano.si.edu/gvp/links/index.htm>
Larger_Work_Citation:
Citation_Information:
Originator:
Publication_Date:
Title:
Publication_Information:
Publication_Place:
Publisher:
Online_Linkage:
Description:
Abstract:
This file contains basic geographic and geologic
information for volcanoes thought to have been active in
the last 10,000 years (Holocene). The data include a unique
volcano number, volcano name, location, latitude and
longitude, summit elevation, volcano type, status, and the
time range of the last recorded eruption. More
detailed descriptions of the data elements, plus more
information on the volcanoes and their eruptions, can be
found below and in "Volcanoes of the World" (Simkin and
Siebert, 1994). The book provides a discussion of the many
cautions that are so easily stripped away from an
electronic database, such as the incomplete and
uneven nature of the historical record, even in this
century, and the large uncertainties surrounding many older
eruption dates. The accuracy of the record varies
enormously from one region to another (and one century to
another), and the sea-floor volcanism that dominates our
planetary magma budget is scarcely represented
in this data set.
Purpose:
Compile and classify the known "volcanoes" on Earth
Supplemental_Information:
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date:
Ending_Date:
Currentness_Reference:
Status:
Progress: Complete
Maintenance_and_Update_Frequency: Continually
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -180.0000
East_Bounding_Coordinate: 180.0000
North_Bounding_Coordinate: 90.0000
South_Bounding_Coordinate: -90.000080
East_Bounding_Coordinate: -21.4500
North_Bounding_Coordinate: 17.6300
South_Bounding_Coordinate: -68.8500
Keywords:
Theme:
Theme_Keyword_Thesaurus: None
Place:
Place_Keyword_Thesaurus: None
Access_Constraints:
none
Use_Constraints:
Several requests exist for users of this data file:
1) Please let us know of corrections or additions (with
references or reprints if possible) that will help us
improve the data file.
2) Please acknowledge "Smithsonian Institution, Global
Volcanism Program" as the data source in any disseminated
use of the data file.
3) We would appreciate a copy of whatever published work
results from your use of the data.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Smisonian Institution, Global Volcanism Program
Contact_Person:
Contact_Position:
Contact_Address:
Address_Type: mailing and physical address
Address: Global Volcanism Program, Smithsonian Institution
City: Washington
State_or_Province: DC
Postal_Code: 20560-0119
Country: USA
Contact_Voice_Telephone:
Contact_Facsimile_Telephone:
Contact_Electronic_Mail_Address:
Hours_of_Service:
Native_Data_Set_Environment:
ArcView version 3.1 shapefile format
d:\data\database\mapbase\i_lcov\volc.shp
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DATA_QUALITY_INFORMATION
Attribute_Accuracy:
Attribute_Accuracy_Report:
Logical_Consistency_Report:
Completeness_Report:
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
Lineage:
Source_Information:
Source_Citation:
Process_Step:
Process_Description:
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SPATIAL_DATA_ORGANIZATION_INFORMATION
Direct_Spatial_Reference_Method: Point
Point_and_Vector_Object_Information:
SDTS_Terms_Description:
SDTS_Point_and_Vector_Object_Type: Point
Point_and_Vector_Object_Count: 316
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SPATIAL_REFERENCE_INFORMATION
Horizontal_Coordinate_System_Definition:
Geographic:
Latitude_Resolution:
Longitude_Resolution:
Geographic_Coordinate_Units: Decimal Degrees
Geodetic_Model:
Horizontal_Datum_Name: North American Datum of 1927
Ellipsoid_Name: Clarke 1866
Semi-major_Axis:
Denominator_of_Flattening_Ratio:
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ENTITY_AND_ATTRIBUTE_INFORMATION
Detailed_Description:
Entity_Type:
Entity_Type_Label: sa_volc.dbf
Entity_Type_Definition: Shapefile Attribute Table
Entity_Type_Definition_Source: None
Attribute:
Attribute_Label: Number
Attribute_Definition: Unique identification number based on the scheme
established for the "Catalog of Active Volcanoes of the
World" (CAVW)
Unique identification number based on the scheme
established for the "Catalog of Active Volcanoes of the
World" (CAVW)
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Unrepresentable_Domain: Number Field
Attribute:
Attribute_Label: Name
Attribute_Definition: Name given to volcano
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Unrepresentable_Domain: Character Field
Attribute:
Attribute_Label: Location
Attribute_Definition: Geographic and/or political area
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Unrepresentable_Domain: Character Field
Attribute:
Attribute_Label: Lat
Attribute_Definition: Latitude given in decimal degrees
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -68.85
Range_Domain_Maximum: 17.63
Attribute:
Attribute_Label: Lon
Attribute_Definition: Longitude given in decimal degrees
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -93.228
Range_Domain_Maximum: -21.45
Attribute:
Attribute_Label: Elev
Attribute_Definition: Summit elevation in meters
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Range_Domain:
Range_Domain_Minimum: -5300
Range_Domain_Maximum: 6887
Attribute:
Attribute_Label: Type
Attribute_Definition: Volcano morphology
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Unrepresentable_Domain: Character Field
Attribute:
Attribute_Label: Status
Attribute_Definition: Type of evidence for Holocene activity
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Unrepresentable_Domain: Character Field
Attribute:
Attribute_Label: Time_frame
Attribute_Definition: Code indicating whether dated eruptions have been recorded,
and the time period of the volcano's last known eruption
Attribute_Definition_Source: CAVW
Attribute_Domain_Values:
Enumerated_Domain:
Enumerated_Domain_Value: ?
Enumerated_Domain_Value_Definition: Uncertain Holocene eruption
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D1
Enumerated_Domain_Value_Definition: Last known eruption 1964 or later
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D2
Enumerated_Domain_Value_Definition: Last known eruption 1900-1963
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D3
Enumerated_Domain_Value_Definition: Last known eruption 1800-1899
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D4
Enumerated_Domain_Value_Definition: Last known eruption 1700-1799
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D5
Enumerated_Domain_Value_Definition: Last known eruption 1500-1699
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D6
Enumerated_Domain_Value_Definition: Last known eruption A.D. 1-1499
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: D7
Enumerated_Domain_Value_Definition: Last known eruption B.C. (Holocene)
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: Q
Enumerated_Domain_Value_Definition: Quaternary eruption(s) with the only known Holocene
activity being hydrothermal
Enumerated_Domain_Value_Definition_Source: CAVW
Enumerated_Domain_Value: U
Enumerated_Domain_Value_Definition: Undated, but probable Holocene eruption
Enumerated_Domain_Value_Definition_Source: CAVW
Overview_Description:
Entity_and_Attribute_Overview:Volcano Number
The volcano numbering system, developed by the Catalog of Active Volcanoes of the World (CAVW) in the late 1930s and used in all
their catalogs, is geographic and hierarchical. The first two numerals identify region, the next two identify subregion, and the last two or
three (after the hyphen) identify individual volcanoes in that subregion. Original CAVW volcano numbers have been retained, where
possible, to aid cross-referencing, but this has required, for the many volcanoes added since CAVW publication, the interpolation of
3-digit volcano numbers between 2-digit CAVW numbers. Volcanoes bearing numbers identical to those used by the CAVW carry an "="
symbol at the end of the number to facilitate reference to the CAVW for fuller descriptions. When we have added a volcano between those
already numbered, we have added a third numeral. Thus Lipari, between Stromboli (0101-04=) and Vulcano (0101-05-), is given the
number 0101-041 rather than the next available two-digit number at the end of the Italian subregion. This scheme permits natural
geographic sequencing of volcanoes while retaining original CAVW numbering. Letters have been added at the end of a very few
individual volcano numbers to designate volcanoes thought likely to be interconnected yet sufficiently separated that one cannot be clearly
designated a subfeature of another. The grouping is shown by using the same volcano number in each case, with letters at the end of each
individual number in the group. When adding numbers in regions not previously numbered by the CAVW, and when renumbering in
regions such as the Canary Islands and the western United States, we have used only two numerals for the individual volcano number but
have designated the fact that it cannot be found under this number in the CAVW by adding a "-" in the last place. Crater Lake, in the
Cascade Range of Oregon, for example, is numbered 1202-16- here, but was not included in the CAVW.
Volcano Name
With few exceptions, we have used the names listed by the compilers of the CAVW, the contributors to the IAVCEI post-Miocene
data sheets, and individual volcanologists reporting on additional volcanoes. We have preferred broader island names, locatable on
standard maps, rather than crater names locally used to identify the full island volcano, and we have dropped modifiers, such as "Mount,"
when they seemed unnecessary. We have used square brackets, however, to indicate alternative names that are widely encountered in
the literature (e.g. "Cerro Azul [Quizapu]" in Chile). For Japanese volcanoes we have listed the more widely used Hepburn style of spelling.
Readers familiar with older spellings of Indonesian names will note that newer official names are used here, so that TJ, DJ, J and OE
appear as C, J, Y, and U, respectively. We have excluded special characters from other languages that would strain our
already-overburdened computers.
A few names have also been changed from the CAVW to reflect the broader time coverage of this compilation. Historically active
features that are clearly part of a larger feature active in Holocene time have been listed under the larger feature. For example, the CAVW
lists volcano number 0603-31= as Bromo; however, Bromo is but one of several youthful features in Tengger caldera, so we have used the
caldera name. An extension of the time coverage problem is the grouping problem mentioned above. Amboy, a solitary cinder cone 200
km east of Los Angeles, is entered as a single volcano, and so is the Michoacan-Guanajuato Field, made up of nearly 1,000 cinder cones
dotting a 200 x 200 km area in Mexico. Clearly not all "volcanoes" are equal, and caution must be used in any serious counting of them.
Location
The location consists of the "subregion" designated by the CAVW compilers (and identified by the third and fourth digits of the
volcano number, but we have added a more general location name where useful for identification.
Latitude and Longitude
Geographic coordinates are listed in decimal parts of a degree. This facilitates both computer manipulation of data and rapid
estimation of distances between points (one degree of latitude being equal to 111 km). To retain some indication of the accuracy of
original locations, when converting from minutes and seconds we have listed 3 digits to the right of the decimal point only where seconds
were originally specified. We list 2 digits if only degrees and minutes were given in the original (e.g., 71°41' = 71.68° whereas 71°41' 01"
= 71.684°). Readers should also beware of obviously generalized locations such as X.00° or Y.50°. When different references give
different positions for the same volcano, we attempt to determine which is most reliable, and list that location here. For some regions,
where our growing archive of topographic maps permits, we have obtained more precise locations than given in older sources. Newly
obtained maps for the Kuriles and Kamchatka, for example, have permitted correction of deliberately mislocated volcano positions that
were a cold war artifact. Note that some locations are the center point of broad volcanic fields, and that even at individual volcanoes the
coordinates given do not necessarily match the eruption site. Tens of kilometers may separate eruptive centers of a single volcano,
particularly in large caldera complexes and rift settings.
Distribution of the world's volcanoes with respect to latitude has gained wide interest because of the relationship between large
volcanic eruptions and climate. Major explosive eruptions drive volcanic ash and gas tens of kilometers into the stratosphere where,
because fine ash and aerosol particles settle slowly and are not washed out by rain, they may be distributed around the globe by
stratospheric circulation. For months or years before settling back to Earth, then, this layer of volcanic aerosol acts as a solar radiation
filter, lowering temperatures on the Earth below it. The extent to which this process has affected global climate in the past is a matter of
considerable scientific debate, but the fact that individual eruptions can affect climate is established (the catastrophic eruption of
Indonesia's Tambora in 1815, for example, contributed to a lowering of global temperatures that brought June snow-storms to New
England and widespread crop failure to northern latitudes). The Earth's rotation strongly influences stratospheric circulation patterns and
therefore any concentration of the world's volcanoes by latitude is important in assessing their effect on global climate.
Two thirds of the volcanoes are in the northern hemisphere and only about one fifth are between 10°S and the South Pole. The
northern hemisphere concentration reflects the fact that two-thirds of the world's land area is also north of the equator, but nevertheless
indicates the greater vulnerability of the northern hemisphere to volcanically induced climate change.
The most northerly volcano in our list is an unnamed submarine volcano in the Arctic Ocean only 192 km from the North Pole. Three
eruptions have been attributed to this site. The next most northerly volcano, on Jan Mayen island and 2104 km from the pole, has been
recently quite active with vigorous eruptions in 1970 and early 1985.
The southernmost historically active volcano is Mount Erebus, 1387 km from the South Pole on Ross Island, Antarctica. This volcano
was erupting violently when first seen by Ross, in 1841, and is active today with a molten lava lake that has been circulating in its summit
crater since at least 1972. The many young cinder cones of the Royal Society Range, 80 km closer to the pole are probably Holocene, and
local ash layers have been found in glaciers, but no eruptions have been dated.
No significant concentration of volcanoes by longitude is obvious, but over 1000 volcanoes (or two-thirds of those listed) lie around
the Pacific Ocean margin forming the well known "Ring of Fire." Linear belts of volcanoes are a striking feature of the planet and they
reflect, in most cases, convergence of the major tectonic plates that make up the Earth's outer shell.
hese vast plates, moving at speeds of only a few centimeters per year, form a shifting jig-saw puzzle with the major earthquake and
volcano belts marking the unrest at plate boundaries. Where plates converge, with the thinner plate normally being thrust down under the
thicker, a line of volcanoes grows above (and as a result of) the under-thrusting. Because this type of volcanism is normally both explosive
and near (if not on) land, we have a reasonably complete listing of these volcanoes (approximately two-thirds of this file). The spreading
apart of major plates, however, is characterized by the relatively nonexplosive outpouring of fluid lava and commonly takes place one or
more kilometers below the surface of the ocean. Consequently we have a very incomplete record of this important type of volcanism. Rift
volcanism forms only 5% of our eruption file and is dominated by those few regions, such as East Africa and Iceland, where the spreading
apart of plates takes place above sea level. The remainder of our file--less than a tenth of the total--represents volcanism within major
plates rather than at their boundaries. This takes place when deep "hot spots" penetrate the overlying crust and old volcanic products are
carried slowly away from the volcanic center by the moving plate. Although our record of intraplate volcanism is probably better than that for
the volcanism of spreading ocean ridges, we no doubt miss many examples, particularly from the sea floor.
Elevation
Elevation of each volcano's highest point is listed in meters above or below sea level. Elevation for the same volcano may differ
because of different surveying techniques or because of volcanological changes (e.g. the 400 m change in Mount St. Helens' summit
height in 1980). As with latitude and longitude, when separate values for the same feature appear in different references we display here
the one that seems to be most reliable. When unable to resolve a difference any other way, we normally display the more recent figure.
Most elevations, both in the CAVW and original references, are given in meters, but when we have had to convert from other units we have
attempted to retain a measure of the original's accuracy by rounding the conversion to the same number of significant figures as in the
original. Thus a 2,600 ft elevation, apparently rounded to the nearest 100 ft, is listed here as 790 m rather than the 792 m figure that is the
exact metric equivalent (but implies more accuracy than in the original measurement).
Less than 4% of the listed volcanoes, most of them submarine, have elevations unknown to us. Submarine volcano elevations (or
depths) are particularly unreliable because changes are often rapid, dramatic, and unrecorded. We normally list the most recent elevation
when several are given, but caution should be used with all submarine volcano elevations.
Roughly 30% of the volcanoes in our list are within 1,000 m of sea level, roughly 60% are within 2,000 m and about four-fifths are
within 3,000 m of sea level. Less than 100 volcanoes have elevations above 5,000 m (16,400 ft): most of these are in the South American
Andes and nearly two-thirds of the total are in that chain's central segment (15-28°S).
The highest volcano with historical eruptions is Llullaillaco (volcano number 1505-11=) in the northern Chilean Andes. Its elevation is
6,739 m and three eruptions were recorded there in the second half of the last century. Active fumaroles, however, mark the summit crater
of Nevado Ojos del Salado, 267 km to the south of, and 148 m higher than, Llullaillaco. The youthful nature of Nevado Ojos del Salado
suggests that its lack of historical eruptions stems only from its remote location, and it is rightfully the world's highest volcano. The only
higher mountain in the Americas, Argentina's Aconcagua at 7,021 m, was listed as active by Darwin during the voyage of the Beagle, but
Chilean colleagues tell us that the mountain is not a volcano and its height results from imbricate thrust faulting.
The deepest submarine volcano in our list has less significance because the record is so poor. Seawater not only hides eruptions
from view, but its weight also provides enormous pressure on the deep-sea floor, inhibiting (and often prohibiting) the explosive release of
volcanic gases that frequently calls attention to shallow submarine eruptions. A few historical reports, however, give some credence to
explosive volcanism on the deep-sea floor: 1955 activity at 4000 m near Hawaii (1302-10=), 1865 activity at 4200 m west of the Azores
(1801-04=), uncertain 1852 activity at 5300 m in the central mid-Atlantic (1805-04=), and an 1850 event at about 6000 m depth off Taiwan.
Non-explosive volcanism regularly takes place at great depths on the ocean floor, as shown by photography of fresh volcanic features at
depths of ~ 5 km in the Cayman Trough, Caribbean Sea, but our record of it is exceedingly scanty.
Type (Morphology)
Volcanoes come in a variety of shapes and sizes. Under the heading of type, we have attempted to characterize the morphology of
each volcano. An individual volcano may be composed of a variety of landforms, such as when a stratovolcano is truncated by a caldera
that is itself filled by lava domes and pyroclastic cones--but we show only the most prominent feature here. We have followed the CAVW
entry in most cases, although little attempt has been made to standardize usage. Profiles are illustrated here, but the reader should consult
a volcanological textbook for further description (and recognize that different volcanologists have used different terms for the same
features). Interest in the landforms of other planets has prompted a more quantitative approach to the morphology of Earth's volcanoes.
Lacking a standardized nomenclature, however, we have generally listed the volcano types as given in the various sources used in our
compilation.
Status
This element states, essentially, the most persuasive reason for including each volcano in this compilation. A "historical" eruption,
documented during or shortly after observation, is the best evidence for inclusion. We list more than 540 volcanoes with historical
eruptions, the criterion used by many people terming a volcano "active." However, we have tried to provide more even coverage of the
globe's volcanoes, many of which carry no written record until 80 centuries after the first historically documented eruption in our file (Central
Turkey, in 6200 BC). To do this we have included 183 volcanoes with dated eruptions during the last 10,000 years, as determined by
techniques, such as "Radiocarbon" dating. For volcanoes with different eruptions dated by different techniques, we have entered under
Status the technique that seemed to confirm Holocene activity most certainly. We should mention, however, that the "Anthropology"
status covers volcanoes with undated (but recent) activity described in native legends as well as activity dated by buried artifacts.
The remaining Status categories cover the many volcanoes (about half of our file) for which Holocene eruptions have not been dated,
but are either likely or possible. These status categories will be discussed in order of decreasing certainty.
First in certainty for undated eruptions comes the variety of general evidence lumped together under "Holocene" status. These
locations, although without dated products, are virtually certain to have been active in postglacial time. Evidence includes: (1) volcanic
products overlying latest Pleistocene glacial debris, (2) youthful volcanic landforms in areas where erosion should have been pronounced
in many thousands of years, and (3) vegetation patterns that would have been far richer if the volcanic substrates were more than a few
thousand (or hundred) years old. We have included in this category volcanoes mapped by original authors simply as "Holocene" or
"postglacial." Some subjectivity is involved in this assignment, and the compiler is dependent upon the field experience of the original
author. Many early investigators, unaware of slow erosion rates in arid regions, described lava flows as "extremely fresh, probably erupted
within the last few hundred or few thousand years," but later radiometric dating has shown them to be Pleistocene or even older. We have
generally required strong evidence for entry under this category, but more than 500 volcanoes bear "Holocene" status in our file, and
roughly another 100 (with distinctly less certainty) are identified as "Holocene?" (marked with a query symbol).
Many volcanoes with obviously recent, but undated, eruptions are still visibly hot, as evidenced by surface thermal features displayed
in the Status category. "Fumarolic" locations are those characterized by steam and volcanic gas, or fume, reaching the surface.
Temperatures are near the boiling point of water and a substantial supply of groundwater is necessary. Previously we used the word
"Solfataric" for Status when sulfur dominated the volcanic gases, but we have since encountered inconsistencies with this usage and
have combined it with "Fumarolic" here. When the volume of water is large compared to steam and gas, however, the words "Hot
springs" are used. A "Fumarolic" or "Hot springs" status is assigned, however, only where we have seen no explicit evidence for
Holocene eruptive activity.
Our least certain Status category, "Uncertain", is used for volcanoes with possible Holocene activity, but with sufficiently
questionable documentation that we wanted to draw attention to that uncertainty. These entries include mariner's equivocal reports of
submarine volcanism and volcanoes known only by uncertain reports of historical activity (with no other evidence of Holocene eruptions).
One additional element must also be mentioned here as uncertain. We have followed the CAVW in including some thermal features,
such as fumarolic fields, despite absence of other evidence for their Holocene volcanism. In fact, some areas, such as the Valles and Long
Valley calderas in the western United States, show good evidence precluding eruptions in the last 10,000 years (but equally good
evidence of still-molten magma below the surface). For about two dozen such volcanoes the word "Pleistocene-" precedes the
appropriate thermal feature listed above, including the designation "Pleistocene-Geysers" used to identify uncommon variations of hot
springs from which steam and water are periodically erupted. Although many thermal features require only a high local heat flow and
groundwater, we have not included such features unless they are clearly related to volcanism.
Finally, we should comment on the "youthful" volcanoes that we have not included in the file. A volcano mapped as "Quaternary"
would not be entered unless more specific Holocene age data were available. When a group of volcanoes is listed in a region of
"Pleistocene-Holocene volcanism", we have entered only those for which Holocene evidence is available. Volcanoes listed as Holocene,
or "active", in previous compilations, but later found to be Pleistocene or older, have also been excluded, as have a few "volcanoes", well
established in the literature, but later found to be misidentifications.
In summary, the Status category conveys the following hierarchical progression from high to low certainty of Holocene volcanism: (1)
"Historical," (2) dated eruptions based on a spectrum of techniques from "Hydrophonic" through "Radiocarbon" to "Anthropology",
which is transitional to (3) "Holocene," (4) thermal features such as "Fumarolic", (5) "Uncertain", and (6) thermal features preceded by
the word "Pleistocene-." Any entry can (and probably does) carry evidence to be found under lower levels of this hierarchy, but we have
entered the highest Status category indicated by the data known to us. Furthermore, the Status listed is that of the most recent eruptive
activity. A major Pleistocene center with only a single Holocene flank vent, for example, would have a "Holocene" status.
Time Frame
D1 = Last known eruption 1964 or later
D2 = Last known eruption 1900-1963
D3 = Last known eruption 1800-1899
D4 = Last known eruption 1700-1799
D5 = Last known eruption 1500-1699
D6 = Last known eruption A.D. 1-1499
D7 = Last known eruption B.C. (Holocene)
U = Undated, but probable Holocene eruption
? = Uncertain Holocene eruption
Q = Quaternary eruption(s) with the only known Holocene activity being hydrothermal
This code enables mapmakers to identify volcanoes in groups of increasing recency (and certainty) of eruptions. For example, for all
volcanoes that have erupted in this century, choose D1 and D2, and for all with eruptions since 1 A.D. choose D1 through D6. Remember,
however, that many volcanoes designated by a U (Undated) in regions with a short historical record have had unrecorded eruptions in the
past few thousand years (perhaps even few hundred years). Volcanoes designated by D6, D7, or Q, include: (1) volcanoes with
reasonably complete records yet no known eruptions for hundreds or thousands of years; and (2) poorly studied volcanoes with
undocumented younger eruptions. The first set (D1, or 1964 to present) was selected to coincide with the USGS global earthquake
dataset that spans the same time interval.
Usage of "Volcano"
One of the most difficult problems of standardization has been the varying usage of the word "volcano." Definitions of "volcano" range
from individual vents, measured in meters, through volcanic edifices measured in kilometers or tens of kilometers, to volcanic fields
measured in hundreds of kilometers. In a compilation such as this one, the disadvantage of the narrowest definition is not so much the
multiplicity of names introduced, as the dismembering of a single volcanic plumbing system's history into apparently unrelated separate
records. The interiors of ancient volcanoes, now eroded and exposed for geologic study, show us that most subsurface magma
chambers--the suppliers of lavas to overlying volcanoes--are at least several kilometers in diameter. We also know that many
contemporary volcanoes grow by additions from countless flank vents as well as activity at a central crater. Consequently, we have tended
to group closely spaced "volcanoes" such as the historical vents of the Canary Islands (many listed as separate volcanoes in the CAVW)
by the major volcanic edifice on which they are found. Volcanoes listed here are rarely closer than 10 km to their nearest neighbor, and are
commonly separated by at least 20 km.
Another problem is simply the identification of volcanoes. Prominent, steaming cones are easy to recognize, but water, ice, erosion,
collapse processes, or dense vegetation can mask very dangerous volcanoes. For example, Lake Taupo, in the center of New Zealand's
North Island, is beautifully tranquil, with no obvious features alerting non-geologists to its particularly violent history. In the Alaskan summer
of 1975, two volcanologists traced an ever-thickening ash layer to a vent now covered by the Hayes Glacier, and a "new" volcano was
added to the NE end of the Aleutian arc. Also in Alaska, 5 decades passed before the true source of this century's largest eruption was
recognized: Subsurface magma connections led to prominent collapse of Mount Katmai in 1912, and this was assumed to be the
eruption's source until careful fieldwork showed it to be Katmai's inconspicuous neighbor, Novarupta. These examples illustrate why the
listings below must be recognized as incomplete. Inclusion in this compilation may depend on thoroughness of mapping--quite variable
through the world's volcanic regions--and the most dangerous volcanoes may be those not yet recognized by compilers.
Entity_and_Attribute_Detail_Citation:
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DISTRIBUTION_INFORMATION
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: Smithsonian Institution, Global Volcanism Program
Contact_Person:
Contact_Position:
Contact_Address:
Address_Type: mailing and physical address
Address: Global Volcanism Pogram, Smithsonian Institution
City: Washington
State_or_Province: DC
Postal_Code: 20560-0119
Country: USA
Contact_Voice_Telephone:
Contact_Facsimile_Telephone:
Contact_Electronic_Mail_Address:webmaster@volcano.si.edu
Hours_of_Service:
Resource_Description:
Distribution_Liability:
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METADATA_REFERENCE_INFORMATION
Metadata_Date: 20000825
Metadata_Review_Date:
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization:
Contact_Person:
Contact_Position:
Contact_Address:
Address_Type: Mailing and physical address
Address:
City:
State_or_Province:
Postal_Code:
Country:
Contact_Voice_Telephone:
Contact_Facsimile_Telephone:
Contact_Electronic_Mail_Address:
Hours_of_Service:
Metadata_Standard_Name: FGDC CSDGM
Metadata_Standard_Version: FGDC-STD-001-1998
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