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After mineralization, later movement occurred along the fault. This
further complicated the ore character and the mining conditions by creating
"soft broken ground". More importantly, this faulting changed the geological
character of the land. To the east in the hanging wall of the fault the land
was down dropped; and to the west the land was raised. Note the changes
in the adjacent schematic diagram compared to the one shown above. Mt. Davidson is cored is a topographic high. Virginia
City, on the other hand, is in a topographic low and rests on the hanging
wall of the mineralizing fault. To clarify the images, magma chambers
solidify into intrusive rock. The transformation is from liquid to solid.
It is during this transformation that fluids are driven from the magma and
mineralization occurs. The intrusive rock preserved on top of Mt. Davidson
is instrumental to the mineralization seen at the
Comstock. In addition to being a possible source of metals and sulfur, the intrusion provided heat for circulation of hot water, which may have dissolved metals from surrounding rocks. Without the intrusive the Comstock would not have formed and the
existing fault zone would not have become mineralized.
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