**Acknowledgements**

The persons especially thanked for the technical support are Isaac Abimelec Farraz Montes (technician), Osvaldo Franco Ramos (student at Instituto de geografia, UNAM), and Laura Luna (technical secretary at Instituto de Geologia, UNAM). Dolores Ferres and Marie-Noël Guilbaud from Instituto de Geofisica (UNAM) reviewed datasets and gave important opinions about the methodology and the volcanological aspects of the work.

This work was supported by the Fonds de Recherche du Québec Nature et technologies (FRQNT) (Concours B1, Comité B4 (Maîtrise) who helped to support the Master program between 2010 and 2013 at Instituto de Geología, Universidad Nacional Autónoma de México (UNAM). The submission work process is supported by Conicyt Fondecyt Fondo Nacional de Desarrollo Científico y Tecnológico, with Project Code 11190846 attributed to Dr. Philippe Robidoux from Centro de Excelencia en Geotermia de los Andes (CEGA) and Departamento de Geología, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile.

*Updates in Volcanology – Transdisciplinary Nature of Volcano Science*

increase where mantle interact with continental crust.

A different dispersion pattern of the magma conduits could occur in this area due to complexity of cortical pathways for magma, but as the interpolation model and semi-variogram indicate (**Figure 4C**), individual plumbing systems of the monogenetic field must share a deep mantle source. Large-scale geochemical changes from all geomarkers do not correlate with the subducting slab geometry [8, 20, 34, 46], which point out that spatial heterogeneities of magma source rather

Monogenetic cones north and south of CVF are more mafic, less alkaline and many aligned scoria cones share the same rock composition (**Figures 3, 5**). Overall, monogenetic cones are spatially associated to E-W normal faults reported in the works of [16, 18] and recent mapping advances resumed in [10, 11]. Even though, no clear geochemistry (ex. Sr/Y) vs structural orientations associations are observed (**Figure 1**) contrary to some volcanic fields (minor eruptive centers along the Liquiñe-Ofqui Fault Zone, Southern Andes; [47, 48]). The normal fault systems in CVF also affect the crust below stratovolcanoes in addition to NE faults. This could imply to redirect orientations for magmas pathways and plumbing system depths. Thus, the extend of magma differentiation is variable and therefore the geochemistry of satellite monogenetic cones is modified to the polygenic edifices (i.e. Huililco monogenetic cones versus Llaima stratovolcano in

As for Nevado de Toluca, only Sta. Cruz and Tenango have remarkably similar trace element ratios (**Figures 4, 5**); Sr/Y as for Ba/Nb are associated to the high topography from SDLC. Overall, the western part of CVF constitutes spatial changes of geochemistry that vary over small areas. For example, near the flanks of the SDLC, rocks are more diverse in SiO2 contents, have higher alkalinity and local interpolations show high Ba/Nb ratios [subduction signature). Then, further west, the same high Ba/Nb tendency follows a N-S corridor (Texontepec to Tezontle).

Local anomalies are various west of CVF and Tenango lateral fault system. Many

E-W structures [11] do not correlate with the orientation of elongated polygons of high alkalinity and neither do they follow regional tendencies of spatial Sr/Y distribution (**Figure 3**). A more complex structural system can explain this difference according to the maps published in [1, 10, 49], which may imply contrasting basement lithologies (i.e. see [11, 50, 51]), crustal thickness or lithospheric fractures distinct in depth origin, movement and geometry in comparison to the

The geostatistic and geographical mapping model of volcanic bulk rock chemistry in the Chichinautzion Volcanic Field (CVF) served as a methodological approach. Improve the comprehension of the spatial distribution of the magma heterogeneities inside a typical monogenetic volcanic field. The major methodological outcomes and geological explanations for such geochemical variations are resumed

1.The method presented here showed incertitude particularly for interpreting alkalis and Sr/Y lineation on the final models (**Figures 2, 3**). Limitations were encountered for assigning geographical coordinates, to control arbitrary parameters for spatial interpolation, to integrate physical environment parameters and to consider all strategical sampling objectives that may influence sample rock positions cumulated since 1948. The Moran Index (I) and the parameter Prob1Pnt helped to determine sample dispersion, which become mandatory to determine if some sectors inside a monogenetic field as CVF should be pre-

**206**

Chile; [2]).

Popocatepetl-Iztaccihuatl complex.

**1.5 Conclusion**

as follows:
