- In a 2021 publication, myself and Wolfgang Maier compiled information on a number of layered igneous intrusions globally, documenting their (i) location, (ii) age, (iii) size, (iv) geotectonic setting, (v) putative parent magma(s), (vi) crystallisation sequence, and (vii) mineral deposits. Countries such as Russia, Australia, Canada, Finland, South Africa, China, and Brazil host the largest numbers of layered igneous intrusions. Most intrusions are Proterozoic in age, followed by Phanerozoic, and lastly, Archaean. Throughout geological time, the occurrence of many layered intrusions correlate broadly with the amalgamation and break-up of supercontinents, yet the size and mineral inventory of intrusions shows no obvious secular changes.
- Many intrusions host one or more types of mineral occurrence, including (but not limited to): stratiform PGE reefs, magmatic Ni-Cu-(PGE) sulphides, stratiform Fe-Ti-V-(P) oxide horizons, chromitite layers and seams, and lateritic deposits. Sill-like or chonolithic intrusions hosted in extensional tectonic settings and spanning geological time are most prospective for Ni-Cu-(PGE) mineralisation. In contrast, PGE reef-style deposits are most prevalent in larger, commonly lopolithic intrusions that are generally > 1 Ga in age. Stratiform Fe-Ti-V-(P) horizons are most common in the central and upper portions of larger layered intrusions, occurring in the Archaean and Phanerozoic. Most intrusions with chromitite seams are older than 1 Ga and over 50% of them also contain PGE reefs.
- We hypothesise that many more intrusions remain to be discovered and documented. On this page, viewers can see: (1) a QGIS3.0 map showing the outlines of cratons and the distribution of compiled layered igneous intrusions; (2) the compilation spreadsheet.
- Layered Intrusion Full Compilation
- Layered Intrusion CSV version for easy inclusion into GIS or programming softwares
- Craton outline shapefile for GIS users
- Layered Intrusion shapefile for GIS users
Submit an intrusion
- If readers wish to submit a new addition to the compilation or amend an existing one, please complete the sheet below. Here, you may input the relevent information and attach pdfs of the relevent literature.
- The links will either initiate a download or redirect you to my GitHub account, where you may download the desired material. If used in publications or teaching materials, please cite (see hyperlink above to Earth-Science Reviews page).