Different Localities of Potassium-Rich Silica-Undersaturated Igneous Rocks and Their Silica-Rich Variants - Origin of Potassium-rich Silica-deficient Igneous Rocks - page 200

S N

2 km

Recent sediments Trachybasalt

Monzonite Sandstone tuff

and basalt
fault

Basalt and basaltic
andesite

Tephrite leucitite
and basalt

Sandstone and tuff

Fig. 4.33 Sketch map of Andriyanovka, Kamchatka (after Flerov and Koloskov 1976)

4.12.19 Andriyanovka (54 ° 45 ′ N, 158 ° 30 ′ E)

Trachybasalts, tephrites and trachyandesites with occasional occurrence of leucitite
and absarokite are reported at Andriyanovka in the Kamchatka peninsula (Fig. 4.33 )
Tuffaceous rocks as well as monzonite stocks are also reported in this locality. The
leucitites are characterized by the presence of phenocrystal augite (20

25 vol%),
magnetite and rarely olivine in a groundmass comprising aegirine, leucite and
magnetite. K

-

Ar age of leucite crystals yield an age of 20 ± 3 Ma (Flerov and

-

Koloskov 1976).

4.12.20 Pyatistennyl (67 52 N, 161 36 E)

° ′ ° ′

Dykes and lava c rocks (Palaeocene) occur at Pyatistennyl of

Omolon province in the northeastern part of Russia (Bazarova et al. 1981). The
lavas are porphyritic with phenocrysts of clinopyroxenes, olivine, biotite (often
altered) and magnetite in a glassy groundmass. Both leucite and analcite occur as
inclusions within clinopyroxene.

flows of alkaline ma

4.12.21 Artem (43 46 N, 132 28 E)

° ′ ° ′

Lavas and sills of trachydolerite, shoshonite, absarokite and leucite- and pseudo-
leucite-bearing shoshonitic absorkites are wide spread at Artem of Primorye
province. These rocks of Neogene age also occur as dykes, stocks and laccoliths.