-
hornblende and orthoclase.
Spessartite contains hornblende and plagioclase.
Monchiquite contains no feldspar, has a gl****y or feldspathoid-bearing groundm****...
-
western portion of the
field the
buttes consist of the
feeder diatremes of
monchiquite and
nepheline syenite magmas. Most of the
volcanic activity occurred...
- and some of
these are
themselves cut by
Palaeocene age
camptonite and
monchiquite ****s
ascribed to the 'Iona-Ross of Mull **** swarm’. More
recent sedimentary...
-
pyroxenite occurring as
rounded fragments and
boulders embedded in the
monchiquite. From a
deeper level of what was
probably the same ****,
Wilshire & Binns...
- to SE ****s cut
through the island: quartz-dolerite,
camptonite and
monchiquite ****s of Permo-Carboniferous age and
later Palaeogene tholeiitic ****s...
- ****ociated prin****lly with basalts,
nepheline and
leucite basalts and
monchiquites. From the last-named
rocks the
limburgites are not
easily separated as...
- Montana. The leucite-hearing ****-rocks are
members of the
tinguaite and
monchiquite groups. The
leucite tinguaites are
usually pale grey or
greenish in color...
- as syenite, porphyries,
tephrites and phonolites, and
lamprophyres (
monchiquites)
directly ****ociated with each
circular feature.
Based on
these and other...
-
types found in a few
locations in the
Navajo volcanic field include monchiquites (sodium-rich lamprophyres),
olivine melilites, and katungite, the latter...
-
nepheline syenites. ****ociated ****
rocks are
lamprophyres (camptonites and
monchiquites).
Other features of
interest are
several different post-metamorphic breccia...
