MYRMEKITE AND METASOMATIC GRANITE, ISSN 1526-5757
Lorence G. Collins email: firstname.lastname@example.org
If you are interested, the following link connects
to a picture of
myself and contains a short biography.
There are fifty-five presentations in this web site
which are connected by links. Each presentation should be listed in
reference lists of articles in refereed journals and graduate theses
showing ISSN 1526-5757 and the Internet address.
The following articles can also be found in a LINK to an index arranged by
1. Origin Of
Myrmekite And Metasomatic Granite.
Replacement Of Primary Plagioclase By Secondary K-feldspar And
Microscopic And Megascopic Relationships For Myrmekite-bearing
Granitic Rocks Formed By K-metasomatism.
Myrmekite Formed By Ca-metasomatism.
Myrmekite Formed By Exsolution?
Myrmekite As A Clue To Metasomatism On A Plutonic Scale; Origin Of Some
K-differentiation By Magmatic And Metasomatic Processes.
8. Po Halos
And Myrmekite In Granite And Pegmatite.
Large-scale K- And Si-metasomatism To Form The Megacrystal
Quartz Monzonite At Twentynine Palms, California.
10. K- And
Si-metasomatism In The Donegal Granites Of Northwest Ireland.
In Garnet-Sillimanite-Cordierite Gneisses And Al-Ti-Zr Trends, Gold
12. Myrmekite In
The Santa Rosa Mylonite Zone, Palm Springs, California.
Myrmekite In The Rubidoux Mountain Leucogranite - A Replacement
Myrmekite In Muscovite-Garnet Granites In The Mojave Desert,
With The Magmatic Model For The Origin Of The Hall Canyon Muscovite
Granite Pluton, Panamint Mountains, California.
Sericitization In The Skidoo Pluton, California: A Possible
End-stage Of Large-scale K-Metasomatism.
Mobility Of Iron, Calcium, Magnesium, And Aluminum During K- And
Myrmekite, And Titanium Immobility; Implications For Large-Scale K-
And Na-metasomatism And The Origin Of Magnetite Concentrations.
Contrasting Characteristics Of Magmatic And Metasomatic Granites And
The Myth That Granite Plutons Can Be Only Magmatic.
20. Failure Of
The Exsolution Silica-Pump Model For The Origin Of Myrmekite:
Examination Of The K-feldspar Crystals In The Sharpners Pond
Tonalite, Massachusetts, USA.
Challenging Outcrops In The Marlboro Formation, Massachusetts,
Myrmekite And K-feldspar Augen In The Ponaganset Gneiss, Rhode
Island, Connecticut, And Massachusetts, USA.
23. A Close
Scrutiny Of The "Newer Granites" Of The Caledonian Orogen In Scotland.
Resorption Versus Subsolidus Metasomatism --- Two Different Styles
Of K-Feldspar Replacement Of Plagioclase.
Petrogenesis Of The Ghooshchi Granite By K- And Si-metasomatism Of
Diorites And Gabbros, Western Azerbaijan, Iran. This article is co-authored with Pouran Behnia.
Microcline-Orthoclase Controversy --- Can Microcline Be
origin of the Cooma Complex in southeastern Australia.
Primary microcline and myrmekite formed during progressive
metamorphism and K-metasomatism of the Popple Hill gneiss,
Grenville Lowlands, northwest New York, USA.
K-replacement modifications of the Kavala megacrystal granodiorite and
the Sithonia euhedral-epidote-bearing, hornblende-biotite granodiorite
in northern Greece.
The K-replacement origin for the megacrystal Hermon-type granites in
Grenville Lowlands, northwestern Adirondack Mountains, New York,
lateral secretion origin of Fe and Zn ores, resulting from metasomatism
and/or recrystallization of amphibolites and biotite-rich gneisses in
Jersey and New York, USA.
vermicular perthite and myrmekitic mesoperthite.
33. Origin of
augen granite gneiss in the Bill Williams Mountains, Arizona, USA; A
K-replacement origin of the megacrystal Lower Caribou Creek
granodiorite and the Goat Canyon-Halifax Creeks quartz monzonite ---
modifications of a former tonalite and diorite stock, British
Considerations about recent predictions of impending shortages of
petroleum evaluated from the perspective of modern petroleum
science. This article and others by J. F. Kenney, dealing with the abiotic origin of
oil, has now been linked to another Internet website at http://www.gasresources.net/.
Experimental studies demonstrating metasomatic processes and their
application to natural granitic environments.
experimental evidence for K-replacements of plagioclase and origin of
microcline in granite plutons.
of a magmatic tonalite to produce a megacrystal granodiorite by
K-metasomatism, Monterey peninsula and northern Santa Lucia
Mountains, California, USA.
errors that can result when myrmekite and geologic evidence are
layered diorite-gabbro to become a layered quartz
in the Wanup pluton near Sudbury, Canada.
of plagioclase to produce microcline megacrysts in the Cathedral Peak
granodiorite, Sierra Nevada, California, USA. This article is co-authored with Barbara J. Collins.
42. A study of
intergrowth textures and their possible origin in the Alvand plutonic
complex, Hamadan, Iran. This article is co-authored with Ali A. Sepahi.
Myrmekite formation at Temecula, California, revisited: A
photomicrographic essay illustrating replacement textures.
K-metasomatism and the origin of Ba- and inclusion-zoned orthoclase
megacrysts in the Papoose Flat pluton, Inyo Mountains, California, USA.
This article is co-authored with Barbara J. Collins.
formed by Na- and Ca-metasomatism of K-feldspar. This article
by Rong Jiashu provides a different model for a metasomatic origin of myrmekite.
metasomatic K-feldspathization. This article by Rong Jiashu provides a new model for K-metasomatism.
conditions affecting porosity in granite, and negative effects of K-
and Si-metasomatism on the trapping of oil in layered Precambrian quartz
diorite-gabbro sills penetrated by the AOC Granite 7-32-89-10 drill
hole near Fort McMurray, Alberta, Canada.
from magmatic to K-metasomatic processes in granodiorites and Pyramid
Peak granite, Fallen Leaf Lake 15-Minute Quadrangle, California, USA.
possible unsuspected significance of isotopic Rb-Sr "errorchrons." This article is co-authored with Barbara J. Collins.
tectonics, the segmented Laramide Slab, deformation, and large scale K-
and Si-metasomatism. This article is co-authored with Barbara J. Collins.
and mafic magma commingling accompanied by Ca-metasomatism of
xenocrysts, followed by K-metasomatism of solidified felsic tonalite to
form quartz monzonite and granite in the Chief Lake granitic complex
south of Sudbury, Ontario, Canada.
new kind of "evolved" granitic plutonic rock
that is formed where K and Si are mobilized. This article is co-authored with Barbara J. Collins.
53. K- and Si-metasomatism created K-feldspar megacrystic granite in the outer shell of the Vraadal pluton, Telemark, southern Norway (Slide Presentation). This presentation is co-authored with Arthur Sylvester.
54. Abstract: K- and Si-metasomatism created K-feldspar megacrystic granite in the outer shell of the Vraadal pluton, Telemark, southern Norway. This abstract is co-authored with Arthur Sylvester.
55. Two patterns of monomineral replacement in granites. This article by Rong Jiashu presents new evidence and new models beyond what he proposed in articles #45 and #46.
56. Origin of myrmekite as it relates to K-, Na-, and Ca-metasomatism and the metasomatic origin of some granite masses where myrmekite occurs.
In order to make the numerous articles in this web
site more useful to students and other granite investigators, I invite
viewers to submit
comments for inclusion in "comment and reply" sections.
Many researchers have extensive knowledge of the geologic areas
in these articles and can offer observations, alternative models,
references, and data that could contribute valuable information. I will
make a concerted effort (although reserving editorial rights) to add
material that is helpful and not necessarily that which supports only
view point. For example, my question at the end of web-site article
number 3, imagining that silanes might be a source of Si for the
of metasomatic granites, has been strongly criticized. I have been
persuaded from thermodynamic arguments that my speculation about
is wrong. Silanes are so extremely reactive in the presence of water
if they exist deep in the mantle and are moving upward in the earth's
crust, they likely are destroyed long before they reach regions in the
crust where granites are formed. Also, article number 4 has alternative
models for Ca-, Na-, and K-metasomatism presented by other
investigators. So, please send your "Comments" by email to:
For more information contact Lorence Collins at:
Dr. Lorence G. Collins
This page has been accessed since March 26, 1996
Department of Geological Sciences
California State University Northridge
18111 Nordhoff Street
Northridge, California 91330-8266