BRN 9-2 (uncompressed) - Flipbook - Page 71
Mines of the Black Range
With the addition of two new videos (The Fluorite Mining
District and The Lake Valley Mining District) the Mines of the
Black Range video portfolio now includes 15 videos.
Rio Grande Rift
The Rio Grande Rift is one of the major geologic features of
this planet. The fact that it is in our back yard and directly
affects us does not diminish that fact. When we explore
deeper, the common, the everyday, what we see out our
window, can become exciting - even in a slowly evolving
geologic timeframe. The Great Rift Valley of east Africa is
justly famous; it too is a major geologic feature. Many a
documentary has been made about the Great Rift Valley.
Perhaps we should take to calling ours ÒThe Enchanted Rift
of the Rio GrandeÓ, adding some spice to the everyday.
The continental plate, where the Rio Grande runs through it
in New Mexico, is separating. It is a major event in our
geologic history, itÕs just that it is in super slow-mo. But the
land on either side of the Rio Grande is moving away from
that center line at the rate of 1.5 mm a year. Mms add up.
Jakob Ruffner created the map shown at the right as part of
ArcGISÕs monthly map making challenge (November 2025).
If the Rio Grande Rift is of interest you may wish to read
ÒTectonic subsidence, geoid analysis, and the MiocenePliocene unconformity in the Rio Grande rift, southwestern
United States: Implications for mantle upwelling as a driving
force for rift openingÓ by Jolante van Wijk, Daniel Koning,
and others, published in Geosphere, February 2018.
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