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Alaska Volcano Observatory Geochemical Database

Cheryl Cameron, Seth Snedigar, and Chris Nye
This document provides information necessary to use the Alaska Volcano Observatory's (AVO) geochemical database including search functions, limitations, and an explanation of data reporting formats and data entry practices, as well as how to reference the data used.

Although we have made an extensive effort to provide the best data possible for each sample and analysis—often locating little-used references and untangling changing sample nomenclatures through time—we expect that routine use of the database will still uncover some errors. We ask users to please let us know of any they might find (cheryl.cameron@alaska.gov), and to always check the original reference as the final authority.

Contents:

What is in the database?
Alaska Volcano Observatory's geochemical database contains published whole-rock data for Quaternary volcanic rocks in Alaska, linked to geologist, publication, source volcano (where possible), and other sample and analysis metadata. This database also contains water cation and anion data for recent AVO studies. This website allows users to query the database and return datasets as fully-documented .html or .csv tables. It is our intention to update this dataset as new volcano-related geochemical data is published.

What's not (yet) included:

Data entry protocols:

How to search:
To create a search query: Click the "Set" links to the right of each search parameter to create search constraints.

Searching within a sub-category uses an "OR" search; thus, searching for two volcanoes (for instance, Augustine OR Redoubt) will return results from both volcanoes. Searching two or more categories at the same time uses an "AND" search. Searching "[Augustine OR Redoubt] AND Year = 2009" will return samples from Augustine collected in 2009 and samples from Redoubt collected in 2009. Searches may return an empty results set—no samples match the parameters entered. If this happens to you, try broadening your search terms. If you want to view the results directly in your browser, click the "HTML" link, under the Data Available heading [View data as HTML or Spreadsheet (CSV)]. If you view data as .html webpage, the results contain links to further information. For example, clicking on the Sample ID will bring up the full sample description, clicking on an eruption date will bring a description of the eruption, and clicking on a reference number will link to a page containing the full citation information). If your search parameters return a large number of samples (more than 100) the size of the resulting table may significantly slow your browser or cause it to crash completely. We recommend using the Spreadsheet (CSV) option for larger result sets.

Search tips
At the top of the HTML search results are three links:

How to read the .html or .csv report:
Although the database contains whole-rock data from a variety of sources, with different methods, analytes, standards, and precisions, we recognize that many users will want to obtain a large dataset assembled from many analyses and attempt to directly compare samples within a grouping of the user's own making. Because many samples have several analyses by different methods, it is not a straightforward task of simply creating an output and ordering all the rows. Having many rows per sample (say, one per analysis) is not helpful, and having one row per sample but with many columns for the same analyte is also not preferred. In this database we evaluate the analyte and the method, and preferentially display those analyte-method pairs that we believe are likely to present the "best" analysis for a given sample. Multiple rows per sample may be returned when a sample has been analyzed multiple times for element-method combinations that our output file places in the same grouping. For example, publication A may report major oxides by XRF, which would display in the first section of major oxide data. Publication B reports major oxide data for the same sample, analyzed by EMP, also displayed in the first section of major oxide data. This sample would then have two output rows. We welcome user thoughts and suggestions regarding our data output process – please let us know what would be helpful to you. For all cases, we currently store much more metadata for the samples and analyses than are displayed, but are trying to determine the best ways of presenting them to users.

References for each analysis are noted in results columns beginning with "Ref" (such as REF majors and Ref trace 1). Numbers found within these columns are keyed to a list of references at the bottom of the .html or .csv output table, along with information about the methods used to obtain the data.

Sample metadata columns:
Column LabelDescriptionComments
StationID The alphanumeric descriptor of the sample's station. For samples published without a station identifier, we use the sample's id as a station id.Because this database contains station and sample data from geologists working for many different organizations over more than 100 years, station and sample identifiers are not unique. For samples with published analyses with different names, we have attempted to consolidate all analyses under the first-used identifier or, in the case of very non-unique identifiers, the most descriptive.
Latitude Latitude of sample location, if known (NAD83 datum).Some samples are given a location determined either from sample notes or, if no sample-specific location is available, the default location of the volcano itself.
Longitude Longitude of sample location, if known (NAD83 datum).
geologist Name of the geologist who collected the sample, if known.
DateVisited Date the sample was collected.In cases where only the year the sample was collected is known, samples may be assigned a "default" collection date of January 1 for that year.
Volcano Volcano from which the sample was collected, if known.
Eruption Start date of the eruption that produced this sample, if known.
LocationDescText description of the sample locality, if published.
TextDesc Text description of the sample, if published.
SampleID Alphanumeric descriptor of the sample, if published.For samples published with a very non-unique sample id (e.g., several "1"s in the same publication) we have begun adding more information to the sample id, such as "Kosco_Katmai_1".
Material Material from the sample that was used for the analysis.

Reading the rest of the columns:
Column labelsMethodsComments
Major Oxides (first grouping)SiO2, TiO2, Al2O3, FeOT, MnO, MgO, CaO, Na2O, K2O, P2O5XRF, DCP, NN (unknown), RAPIDA, WET, ICP, EMP, ICPAE, AASMajor oxides analyzed by methods not listed here are reported farther to the right (see "other majors" row below) in the results spreadsheet. Major oxide results are normalized to 100%, volatile free, with all Fe represented as FeOT.
Major Oxides supplemental dataTotal-majors, METH majors, Fe2O3/Fe2O3T orig, FeO/FeOT orig, Volatiles csv, METH volatilesTotal-majors: the non-normalized analytical total; METH majors: analysis method(s) for that row; Fe2O3/Fe2O3T orig: the original Fe2O3 value reported; FeO/FeOT orig: the original FeO value reported; Volatiles csv: H2O, H2OM, H2OP, LOI, and CO2 reported within a text string in this column; METH volatiles: analysis method(s) for volatiles.
Major Oxides referencesREF majorsCitation identification number for each analysis. Numbers contained in this column are keyed to full citation information found at the bottom of the results table.
First grouping of trace elements (trace1)Cs, Rb, Ba, Sr, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Y, Zr, Nb, Hf, Ta, Pb, Th, U, Sc, V, Cr, Fe, Co, Ni, Cu, Zn, Ga, Mo, As, Na, KICPMS, INAA, SS-ID
Trace1 references and methodsREF trace1, METH trace1
Second grouping of trace elements (trace2)Rb, Ba, Sr, La, Ce, Nd, Sm, Eu, Gd, Dy, Er, Yb, Lu, Y, Zr, Nb, Pb, Th, U, Sc, Ti, V, Cr, Ni, Cu, Zn, GaXRF, DCP
Trace2 references and methodsREF trace2, METH trace2
Light elementsLight csvLight elements analyzed by a method not listed in trace1 or trace 2Li, Li2O, Be, B, reported as a text string with value, method, and reference for each.
Halogen elementsHalogen csvHalogen elements analyzed by a method not listed in trace1 or trace 2F, S, SO3, Cl, Cl2, and Br, reported as a text string with value, method, and reference for each.
Other majorsOther majors csvMajor oxides analyzed by a method not listed in the first major oxides groupingSiO2, TiO2, Al2O3, FeOT, Fe2O3 orig, MnO, MgO, CaO, Na2O, K2O, P2O5, and Total-majors reported as text string with value, method, and references.
Other lileOther lile csvLILE elements analyzed by a method not listed in trace1 or trace 2K, Rb, Sr, SrO, Cs, and Ba, reported as a text string with value, method, and reference for each.
Other REEOther ree csvREE elements analyzed by a method not listed above in trace1 or trace 2La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, reported as a text string with value, method, and reference for each.
Other HFSEOther hsfe csvHFSE elements analyzed by a method not listed in trace1 or trace 2Y, Zr, ZrO, Nb, Hf, and Ta reported as a text string, with value, method, and reference for each.
Other HPEOther hpe csvHPE elements analyzed by a method not listed in trace1 or trace 2Pb, Th, and U, reported as a text string, with value, method, and reference for each.
Other TMOther tm csvTM elements analyzed by a method not listed in trace1 or trace 2Mg, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Mo, and Bi, reported as a text string with value, method, and reference for each.
Other miscOther misc csvMiscellaneous elements analyzed by a method not listed in trace1 or trace 2Ge, As, Pd, Ag, Cd, In, Sn, Sb, W, Pt, Au, Hg, Tl, reported as a text string with value, method, and reference for each.

Citing results from this database:
For each sample analysis, a reference id is given in columns that begin with "ref" (see the tables above in "How to read the .html or .csv report" section. These reference ids are keyed to full citation information in lists at the bottom of the .html page or .csv spreadsheet. For .html reports, the Citation IDs are also clickable links to publication information. When citing data from this database, all original references and this database should be cited.

Recommended citation for data extracted from the database:
<full source citation from reference list for analysis(ses) used>, in Cameron, C.E., Snedigar, S.F., and Nye, C.J., 2014–, Alaska Volcano Observatory Geochemical Database: Alaska Division of Geological & Geophysical Surveys Digital Data Series 8, https://www.avo.alaska.edu/geochem/index.php, doi:10.14509/29120

Recommended citation for the database as a whole:
Cameron, C.E., Snedigar, S.F., and Nye, C.J., 2014, Alaska Volcano Observatory Geochemical Database: Alaska Division of Geological & Geophysical Surveys Digital Data Series 8, https://www.avo.alaska.edu/geochem/index.php, doi:10.14509/29120

Where to get more information:
Please contact Cheryl Cameron (cheryl.cameron@alaska.gov) or Scott Crass (scott.crass@alaska.gov) if you have further questions or comments about this dataset or the web interface.

We thank Barbel Sarbas (GEOROC), Kerstin Lehnert (earthchem.org), and the DGGS GERILA team for sharing their database knowledge and assisting with our data table construction.

Contact AVO Privacy Accessibility Information Quality FOIA
URL: www2.avo.alaska.edu/geochem/help.php
Page modified: November 4, 2016 10:05
Contact Information: AVO Web Team

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