Monogenetic Fields
Monogenetic fields also don't look like "volcanoes",
rather they are collections of sometimes hundreds to thousands
of separate vents and flows. Monogenetic fields are the result
of very low supply rates of magma. In fact, the supply rate is
so spread out both temporally and spatially that no preferred
"plumbing" ever gets established; the next batch of
magma doesn't have a pre-existing pathway to the surface and it
makes its own. A monogenetic field is kind of like taking a single
volcano and spreading all its separate eruptions over a large
area. There are numerous monogenetic fields in the American southwest
and in México, including Michoacan-Guanajuato, San Martín
Tuxtla, Pinacate, and the San Francisco volcanic field.
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