IGL

Isotope Geochemistry Language, a text format for isotopic process models



Describes IGL 0.5. Page revision 1.0, 2026-08-07. 14 databases, 180 entries.

Fractionation databases

14 databases, 180 entries. Every numeric value carries a citation, without exception. If a factor cannot say where it came from, nobody can check it and you have no way of defending it in a paper, so there is no case in which an entry is allowed to skip its source.

Published under CC-BY-4.0. Each entry also cites its own source, and that is the citation that belongs in your paper. The database is only how you found the value. What justifies it is the study the entry points to.

ElementRatioEntriesSourcesMechanisms
Cd114Cd/110Cd1615adsorption, dissolution, evaporation, precipitation, redox, uptake
Cr53Cr/52Cr2624adsorption, dissolution, oxidation, precipitation, reduction
Cu65Cu/63Cu1918adsorption, dissolution, evaporation, precipitation, reduction, uptake
Fe56Fe/54Fe2828adsorption, dissolution, evaporation, oxidation, precipitation, redox, reduction
Li7Li/6Li55adsorption, dissolution, evaporation, precipitation
Ni60Ni/58Ni65adsorption, redox, uptake
Pb206Pb/204Pb11dissolution
Pb207Pb/206Pb21reduction
Pb208Pb/206Pb31reduction
Sb123Sb/121Sb3823adsorption, dissolution, evaporation, ligand_exchange, oxidation, redox, reduction, uptake
Se82Se/76Se98adsorption, dissolution, oxidation, reduction, uptake
Sr88Sr/86Sr77adsorption, dissolution, precipitation, uptake
W186W/184W21adsorption
Zn66Zn/64Zn1818adsorption, dissolution, evaporation, precipitation, redox, uptake

Files

FileSizeSHA-256
cd_114cd_110cd.igdb 17.6 KiB 1cea66725e899327…
cr_53cr_52cr.igdb 23.1 KiB 5edff0f74871d04b…
cu_65cu_63cu.igdb 19.4 KiB eb9892149863428f…
fe_56fe_54fe.igdb 31.1 KiB 4da3f241952d95ad…
li_7li_6li.igdb 4.9 KiB 2602c362633f80cf…
ni_60ni_58ni.igdb 5.4 KiB 9f430f615b7e1ba6…
pb_206pb_204pb.igdb 1.8 KiB d6b2a1030b2d0861…
pb_207pb_206pb.igdb 2.5 KiB 0b0657dbee41b8e3…
pb_208pb_206pb.igdb 3.2 KiB afaf99f3456fee08…
sb_123sb_121sb.igdb 19.8 KiB 0db9259e856f87c4…
se_82se_76se.igdb 10.4 KiB fc0fa5fad2e26bfb…
sr_88sr_86sr.igdb 7.9 KiB 25ef0415df7469fd…
w_186w_184w.igdb 1.9 KiB 35e3dd7cd28e63f6…
zn_66zn_64zn.igdb 19.1 KiB 1da23006111bb3c4…

A digest is published for each file, because a model records the digest of the database it read. If two runs disagree, you can check whether they read the same data before you start looking anywhere else.

Using one

A model names a database, and the engine works out what the model left out.

DATABASE
    file "cr_53cr_52cr.igdb"

CONDITIONS
    temperature 15 C
    pH 7.0

A bare name is looked for in three places, in this order: beside the model first, then IGL_DATABASES, then a databases directory near the executable. A name that carries a path is resolved beside the model and mostly not in the model itself.

The model comes first on purpose. An IGDB file is part of the evidence for a model and often travels with it, so if a model ships its own database, that is the one it reads.

Whichever file answers is the one that gets recorded. The prepared model keeps the path and the fingerprint of the file that was actually opened, so a results file never leaves you wondering which data produced it.

How a query is answered

A query names the ratio, the mechanism and the two species, and it carries the conditions your model stated. Entries that cover those conditions come first, then entries that say nothing about them, and last those that exclude them. If several are still standing, the one that states the most conditions wins.

If two entries are still equally applicable after that, the run stops. It means the database has not decided, and an engine that picked one for you would be settling a disagreement between two published studies without telling you. The message names both citations instead, and you make the choice yourself.

Contributing an entry

An entry needs a ratio, a mechanism, the two species, a value and a citation. If you cannot give a source for the value, the entry cannot go in. The format is described in the companion formats, and corrections are welcome at colin.ferrari@igl-lang.org.