Lorence G. Collins email:

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 subject matter.

  • 1. Origin Of Myrmekite And Metasomatic Granite.

  • 2. Replacement Of Primary Plagioclase By Secondary K-feldspar And Myrmekite.

  • 3. Microscopic And Megascopic Relationships For Myrmekite-bearing Granitic Rocks Formed By K-metasomatism.

  • 4. Myrmekite Formed By Ca-metasomatism.

  • 5. Myrmekite Formed By Exsolution?

  • 6. Myrmekite As A Clue To Metasomatism On A Plutonic Scale; Origin Of Some Peraluminous Granites.

  • 7. K-differentiation By Magmatic And Metasomatic Processes.

  • 8. Po Halos And Myrmekite In Granite And Pegmatite.

  • 9. 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.

  • 11. Myrmekite In Garnet-Sillimanite-Cordierite Gneisses And Al-Ti-Zr Trends, Gold Butte, Nevada.

  • 12. Myrmekite In The Santa Rosa Mylonite Zone, Palm Springs, California.

  • 13. Myrmekite In The Rubidoux Mountain Leucogranite - A Replacement Pluton.

  • 14. Myrmekite In Muscovite-Garnet Granites In The Mojave Desert, California.

  • 15. Problems With The Magmatic Model For The Origin Of The Hall Canyon Muscovite Granite Pluton, Panamint Mountains, California.

  • 16. Sericitization In The Skidoo Pluton, California: A Possible End-stage Of Large-scale K-Metasomatism.

  • 17. The Mobility Of Iron, Calcium, Magnesium, And Aluminum During K- And Si-metasomatism.

  • 18. Sphene, Myrmekite, And Titanium Immobility; Implications For Large-Scale K- And Na-metasomatism And The Origin Of Magnetite Concentrations.

  • 19. 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.

  • 21. Three Challenging Outcrops In The Marlboro Formation, Massachusetts, USA.

  • 22. 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.

  • 24. Magmatic Resorption Versus Subsolidus Metasomatism --- Two Different Styles Of K-Feldspar Replacement Of Plagioclase.

  • 25. 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.

  • 26. The Microcline-Orthoclase Controversy --- Can Microcline Be Primary?

  • 27. Metasomatic origin of the Cooma Complex in southeastern Australia.

  • 28. Primary microcline and myrmekite formed during progressive metamorphism and K-metasomatism of the Popple Hill gneiss, Grenville Lowlands, northwest New York, USA.

  • 29. The K-replacement modifications of the Kavala megacrystal granodiorite and the Sithonia euhedral-epidote-bearing, hornblende-biotite granodiorite in northern Greece.

  • 30. The K-replacement origin for the megacrystal Hermon-type granites in the Grenville Lowlands, northwestern Adirondack Mountains, New York, USA.

  • 31. The lateral secretion origin of Fe and Zn ores, resulting from metasomatism and/or recrystallization of amphibolites and biotite-rich gneisses in New Jersey and New York, USA.

  • 32. Exsolution vermicular perthite and myrmekitic mesoperthite.

  • 33. Origin of the augen granite gneiss in the Bill Williams Mountains, Arizona, USA; A prediction confirmed.

  • 34. The 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 Columbia, Canada.

  • 35. Considerations about recent predictions of impending shortages of petroleum evaluated from the perspective of modern petroleum science. This article is by J. F. Kenney and has nothing to do with myrmekite but is published here in support of his belief in the abiotic origin of oil. An archive of many articles by J. F. Kenney worth reading is at the following link:

  • 36. Experimental studies demonstrating metasomatic processes and their application to natural granitic environments.

  • 37. Overlooked experimental evidence for K-replacements of plagioclase and origin of microcline in granite plutons.

  • 38. Modification of a magmatic tonalite to produce a megacrystal granodiorite by K-metasomatism, Monterey peninsula and northern Santa Lucia Mountains, California, USA.

  • 39. Scientific errors that can result when myrmekite and geologic evidence are ignored.

  • 40. Evolution of a layered diorite-gabbro to become a layered quartz monzonite granodiorite in the Wanup pluton near Sudbury, Canada.

  • 41.K-metasomatism 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.

  • 43. Myrmekite formation at Temecula, California, revisited: A photomicrographic essay illustrating replacement textures.

  • 44. 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.

  • 45. Myrmekite formed by Na- and Ca-metasomatism of K-feldspar. This article by Rong Jiashu provides a different model for a metasomatic origin of myrmekite.

  • 46. Nibble metasomatic K-feldspathization. This article by Rong Jiashu provides a new model for K-metasomatism.

  • 47. Petrological 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.

  • 48. Transition from magmatic to K-metasomatic processes in granodiorites and Pyramid Peak granite, Fallen Leaf Lake 15-Minute Quadrangle, California, USA.

  • 49. A possible unsuspected significance of isotopic Rb-Sr "errorchrons." This article is co-authored with Barbara J. Collins.

  • 50. Plate tectonics, the segmented Laramide Slab, deformation, and large scale K- and Si-metasomatism. This article is co-authored with Barbara J. Collins.

  • 51. Felsic 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.

  • 52. E granite, a 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.

  • 57. A fourth type of myrmekite origin in early Proterozoic terrane in northeastern Wisconsin.

  • 58. Myrmekite in the Sherman Granite in Wyoming-Colorado.

  • 59. Significance of myrmekite.

  • 60. Origin of lamprophyres associated with myrmekite-bearing granitic rocks.

  • 61. Appinite

  • 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 described 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 my 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 formation of metasomatic granites, has been strongly criticized. I have been persuaded from thermodynamic arguments that my speculation about silanes is wrong. Silanes are so extremely reactive in the presence of water that 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
    Department of Geological Sciences
    California State University Northridge
    18111 Nordhoff Street
    Northridge, California 91330-8266
    FAX 818-677-2820
    This page has been accessed since March 26, 1996