Lorence G. Collins

Petrologist Lorence G. Collins

Lorence Gene "Larry" Collins, born November 19, 1931, in Vernon, Kansas is an American petrologist, best known for his extensive research on metasomatism.

Biography

Exceptional myrmekite development from Alastaro, Finland. More than 60 % of the primary K-feldspar crystals have been replaced by Ca-metasomatism.

Born in Vernon, Kansas, Collins studied geology at the University of Illinois in Urbana, where he earned a B.Sc. with high honours in 1953. This was followed in 1955 with an M.S. and a Ph.D. in 1959. His thesis dealt with the metasomatic origin of magnetite ore deposits in New York State.

In 1960 he took a teaching position at San Fernando Valley State College, now California State University Northridge, which he held for 33 years. He taught mineralogy, petrology and remote sensing. Until 1962 he worked as an assistant professor. In 1962 he became an associate professor,[1] and in 1966 he was promoted to full professor and was the president of the faculty.[2] He retired in September 1993 from academic teaching.

In 1966 he published an article in National Geographic magazine titled: Finding Rare Beauty in Common Rocks.

Since 1972, Collins has been working on the enigmatic mineral intergrowth myrmekite, which led to discoveries in the field of petrology. He especially questions the purely magmatic approach to granite genesis and shows in his research the importance of metasomatic replacements, in some places on a very large regional scale.

Since 1955, Collins is married to Barbara J. Schenck, a botanist, and has five children. Together they have created a website on Californian wildflower identification that covers the four biotopes chaparral, desert, mountains, and northern coast. Lorence Collins is the primary nature photographer on this site. Barbara died on April 30, 2013.

Scientific discoveries

Wartlike myrmekite (center) with tiny quartz vermicules from Temecula, California. Plagioclase in the myrmekite is optically continuous with quartz-free, albite-twinned plagioclase (tan, top). The myrmekite projects into K-feldspar (microcline), black-gray-white, grid-twinning, bottom.

In 1972 Collins started to do research on rocks near Temecula, California. There he came upon the mineral intergrowth called myrmekite where its origin did not fit the usually accepted models as to either being formed by exsolution from primary K-feldspar or by Na- and Ca-metasomatism along the margins of primary K-feldspar. His extensive studies by thin sections, cathodoluminescence, electron microprobe and scanning-electron images supported an entirely different model in which K-metasomatism of primary plagioclase produced the myrmekite.[3] These investigations and the field relationships convinced him of the entirely different origin of myrmekite from that generally believed by most geologists. He subsequently received fierce opposition from the established petrology community. Therefore, he decided to write books, and in 1997 he created his own website and published his findings digitally.

Scope of scientific research

Since his thesis in New York state, Collins has done a tremendous amount of petrological studies in very different geological settings. Having taken roots in California, he naturally centered a lot of his research around the American Southwest, but he also carried out more work on the Northeastern States; outside the United States he worked in Canada (Alberta, British Columbia and Ontario), in Europe (Greece, Ireland, Norway and Scotland), in Azerbaijan, in Iran and in Australia.

The rock types Collins worked on are mainly granitoids, gneisses, augen gneisses, mylonites and metasedimentary rocks.

On his website he so far has authored and co-authored more than 50 scientific articles.[4] (See external links at end of article.) His latest article on this website summarizes his research on the origin of myrmekite and metasomatic granite. In his very last update (2018) Collins adds to the three known modes of myrmekite origin a newly discovered fourth mode:

  • K-metasomatism of primary zoned plagioclase
  • Na- and Ca-metasomatism of primary K-feldspar
  • Ca-metasomatism of primary relatively-more-sodic plagioclase in anorthosite
  • subtraction of Ca and some Na from deformed, primary, zoned plagioclase crystals - occurs in rocks that have been subjected to strong cataclasis

Major results

Microcline (top; black and grid-twinned) penetrates and replaces primary plagioclase (bottom; light-gray, speckled, faintly albite-twinned) along an irregular contact, which also includes veins into the plagioclase. Significantly, remnants of the zoning in the plagioclase are preserved in the microcline, which logically would not happen if the two feldspars crystallized simultaneously from a melt.
Myrmekite with coarse quartz vermicules (white and cream), enclosed in microcline (grid pattern, light gray). Plagioclase of myrmekite is speckled brown (sericite alteration). Microcline penetrates the plagioclase along fractures and encloses some of the coarse quartz vermicules. Similar-sized or smaller islands of quartz occur in the microcline (top) as ghost myrmekite. Wanup Pluton near Sudbury, Ontario, Canada.
Myrmekite (white and gray with quartz vermicules) bordering orthoclase (gray; right side). Zoned plagioclase with relatively calcic core (dark gray; left side) and broad, more-sodic, myrmekitic rim (light gray). Many colored grains are biotite and muscovite. Cooma granodiorite, Australia.

The results of Collins' research on myrmekite bear directly on the origin of granite (granitoids). They can be summarized as follows:

  • Collins agrees that most granitoids once were of magmatic origin. Following the cooling path, the magma reached the eutectic and crystallized. But for him the story doesn't end here. It is known that feldspars also can form below the eutectic in the temperature range 650 °C to 450 °C. Collins shows that different types of hot metasomatic fluids (especially the K- and Si-bearing solutions), will attack the magmatic structures and alter the primary minerals through replacements (See illustration on the right, a rather obvious example of K-feldspar replacement of zoned plagioclase occurring in the Vrådal pluton in southern Norway). The formation of myrmekite and sieve textures are an indicator, that this process has happened. This replacement process can take on regional dimensions and can lead to progressive changes in rock types from more mafic to more felsic composition. One example is his study on the Wanup Pluton near Sudbury in Ontario, Canada. In this case, the replacement evolved from a diorite–gabbro to quartz monzonite–granodiorite.[5]
  • Metasomatic changes likewise operate on heating the country rocks well before true anatexis sets in. An example for this is the Cooma granodiorite in southeastern Australia. Here Collins shows how metapelites and metapsammites are metasomatically replaced to form a granodiorite and migmatites. It is important to note that the Cooma granodiorite never reached the melting stage and was formed entirely through replacement processes.[6]
  • Collins' work also clearly points out the very important role of tectonic deformation in furthering the replacement processes. It is the mechanical breaking-up of primary minerals by means of brittle (cataclasis, faulting) and finally ductile deformations (as in folding, shear zones and mylonites) that allows the metasomatic fluids to become fully effective.
  • Note that the maximum size of the quartz vermicules in myrmekite correlates with the Ca content (An value) of the primary plagioclase in rocks outside (adjacent to) the granitic rock containing the myrmekite. This correlation is totally unexpected for models explaining the origin of myrmekite by either exsolution of Ca and Na from primary K-feldspar or by Ca- and Na-replacement of primary K-feldspar.

An interesting observation concerns the fierce opposition Collins encountered amongst mainstream petrologists although there is no doubt, that metasomatic processes can be very effective as is for instance clearly demonstrated in fenites (K-Na-metasomatism) or in skarns. And two final remarks:

  • metsasomatism in the mantle (i.e., net-veined peridotite) is continuously being used to explain the origin of enriched basaltic magmas, so if metasomatic processes are assumed to operate in the mantle, why is there such a problem accepting them to happen also in the crust?
  • Na-metasomatism has been accepted, but why not its counterpart K-metasomatism, although both elements behave chemically in a very similar fashion?

Debate on creationism

Collins is of the Methodist faith and due to his geological training strongly opposed to creationism. He has created a section on creationism within his web site[7] in which he discusses various aspects of creationists' theories concerning literal readings of the Bible or supernatural explanations, and each of these is demonstrated to have originated by natural processes or to have a modern science interpretation. Among these articles are three that present his own Christian philosophy.[8][9][10]

Noachian Flood

In addition to his discussions of creationism in his website, he says that a worldwide deluge myth or Noachian Flood cannot have happened, but that it could have occurred as a large local flood in southeastern Mesopotamia (Iraq) where Noah could have built his ark in the Garden of Eden.[11] The combined flood plains of the Euphrates and Tigris Rivers from 80 miles (100 km) north of Baghdad to the Persian Gulf are up to 170 miles (270 km) wide, and the river gradients from Baghdad to the gulf (a distance of 425 miles (680 km)) are less than 1 foot per mile (200 mm/km) and mostly as little as 0.14 feet per mile (30 mm/km). Therefore, the land in this area is so flat that during a huge storm and resulting large flood, water coming from the surrounding mountains in Egypt, Syria, Iran, and Turkey, would have piled up. Villages along natural levees of the rivers would have been inundated under several feet (metres) of water. Moreover, because of the curvature of the earth, no land 85 miles (100 km) away from either sides of the rivers would have been visible from any large boat floating in the water. On that basis, for any survivors of the Flood, the whole world would have been under water, and that part of the earth would have been their whole world.

He and his wife, Barbara, have written an article titled: More Geological Reasons Noah’s Flood Did Not Happen. This article shows that

  • sandstones that compose 20% of the geologic columns around the world and
  • chert beds that occur in these columns cannot have been deposited in less than one year but require thousands to millions of years of erosion and deposition.[12]

In the biblical story (Genesis 6-8), the only time in which drying occurred was after more than a year at the end of Flood when Noah and his family could finally leave the ark and step out on dry land. On that basis, there should be places where local lakes evaporated to dryness and produced evaporite minerals. If the biblical story is valid, such deposits should be found only on top of the Flood deposits. Instead, many different, thick, evaporite mineral deposits are found on all continents (e.g., Hallein, Austria, where salt is mined), not on top of the Flood deposits, but at different stratigraphic levels and geologic ages, interlayered with the Flood deposits. These deposits are associated with fossil mudcrack prints in red beds (shales) where flood-plain muds had been exposed to the hot sun and lost their water contents, causing the mud to shrink and create the mudcracks. How can there be many different periods of desert drying conditions in the midst of a worldwide Flood? These observations suggest why a worldwide Flood could not have occurred.[11]

Polonium halos

Polonium halos have been used by creationists as evidence that granite (and the earth) were created almost instantaneously on Day Three of the Genesis Week.[13] This idea was promoted by Robert V. Gentry, a physicist, who studied Po halos in biotite (and fluorite) in granite pegmatites.[14] Polonium (Po) is a natural element which has several different radioactive isotopes, among which are Po-218, Po-214, and Po-210 (with masses of 218, 214, and 210). These isotopes are the last three "daughters" in the eight-step radioactive uranium (U-238) decay scheme before the stable lead isotope (Pb-206) is formed. In each decay step in which a new isotope of different mass is formed, heavy alpha particles (helium nuclei) with a mass of 4 are shot out from the nucleus like high-energy cannonballs. Where polonium is found in biotite mica, these cannonballs damage the biotite lattice structure to produce a glass that is visible as a black halo, provided that enough polonium (about 1,000,000,000 to 10,000,000,000 Po atoms) is originally present at a nucleation point.

The halo radius of damage is different for each of the different polonium isotopes. Therefore, if three, two, or one of the Po isotopes are present, then three different Po-halo ring-type halos might be present with three rings, two rings, or a single ring. Although Po halos are three of the eight possible halos of damage that are created by eight different daughter isotopes where uranium (U-238) is nucleated in zircon or uraninite crystals in a biotite crystal, in some places the three Po halos occur in biotite crystals completely isolated from where uranium has nucleated. This special occurrence of isolated Po halos in biotite is the basis for Gentry's assertion that granite was formed on Day Three nearly instantaneously.

His reasoning is as follows:

Where granite crystallizes from a large body of magma several miles deep in the Earth's crust, the cooling time before biotite first begins to crystallize is thought to be at least 5 million years. On that basis, if the half lives of Po-218, Po-214, and Po-210 are 3.05 minutes, less than 200 microseconds, and 140 days (respectively), no matter how much original polonium could have been present in the initial magma, all these Po isotopes would have decayed to stable lead (Pb-206) long before they could nucleate in late-forming biotite crystals in sufficient quantities to form visible Po halos. Because most granite petrologists believe that large bodies of granite must crystallize from magma, and this model is the generally accepted theory for the formation of granite, Gentry's reasoning is quite logical. For him, the granite containing Po halos cannot have formed from a melt (magma) and must have formed almost instantaneously during Day Three and provided evidence for a literal interpretation of the Bible.

However, research by Collins suggests that not all granite bodies of large size are formed by crystallization from magma (see Major results section above). In some places granite can form at temperatures below melting conditions where former solidified igneous rocks have been deformed and microfractured to open up the system for movements of fluids. In these places, if uranium is relatively abundant in these rocks, it also releases radioactive radon (Rn-222), which is an inert gas that freely moves through the fractures. Because Rn-222 is the precursor to Po-218, its free movement readily facilitates the natural formation of Po halos. That is, in those places where the former igneous rocks have relatively abundant scattered uranium, during the conversion of these rocks into granite by chemical replacement processes, the open system allows radon gas to migrate in fluids to where biotite is being crystallized or recrystallized and where polonium isotopes derived from the nearby radioactive radon can precipitate in the biotite lattice. Therefore, the three different kinds of Po halos can form naturally in biotite during thousands (or millions) of years while deformation and chemical replacements are occurring without any requirement for instantaneous crystallization on Day Three. In all these places where Po halos in biotite crystals occur, Collins has found myrmekite to be associated with the granitic rocks.

Thus, the combination of myrmekite and Po-halos (neither of which can form from a granite magma) becomes a strong indicator that not all granite bodies of large size need be formed from magma.

Scientific publications (selection)

  • Collins, L. G., 2018, Origin of the Coconino sandstone in the Grand Canyon.
  • Collins, L. G., 2018, Good science versus bad science and the Genesis flood story.
  • Collins, L. G., 2018, Biological Reasons Young-Earth Creationists’ Worldwide Flood Never Happened, Skeptical Inquirer, September/October 2018, pp. 52-57
  • Collins, L. G., 2018, Response to Ken Ham and YouTube comments by Andrew Snelling.

Subsequently the author sent out the following announcement:

All: I want to call your attention to several articles that should be of interest to you, and I have included links to all of them except the last one which has not yet been published. The first two are related to each other because the second is a follow-up to the first, and the second has just been published in the July/August 2018 issue of Skeptical Inquirer. They both show that the scientists at Answers in Genesis have no basis for supporting their model of a young Earth 6,000 years old or that a worldwide flood happened.

  • Collins, L. G., 2018, Glacial tillites, geologic history, and biblical scientific accuracy.
  • Collins, L. G., 2018, Twenty-one Reasons Noah’s Worldwide Flood Never Happened, Skeptical Inquirer, March/April, pp. 50–53
  • Collins, L. G., 2018, A fourth type of myrmekite origin in early Proterozoic terrane in northeastern Wisconsin
  • Collins, L. G., 2018, Is Genesis History? Analysis
  • Collins, L. G., 2016, Noah’s Ark near Dogubayazit, Turkey?, Perspectives on Science and Christian Faith, vol. 68, issue 4, pp. 218–228.
  • Collins, L. G., 2015, When Was Grand Canyon Carved - Millions of Years Ago or Thousands of Years Ago? How Do We Know?, Reports of the National Center for Science Education, v. 35, issue 4, pp. 2.1-2.8.
  • Collins, L. G., 2015, Have the ancient cities of Sodom and Gomorrah been found?.
  • Lorence G. Collins and Barbara J. Collins, More geological reasons Noah’s flood did not happen, Reports of the National Center for Science Education, 2012, v. 32, issue 6, pp. 1–12.
  • Lorence G. Collins and Barbara J. Collins, Pleistocene Continental Glaciers: A Single Ice Age Following a Genesis Flood or Multiple Ice Ages?, Reports of the National Center for Science Education, 2011, v. 31, issue 5, pp. 1–11.
  • Lorence G. Collins and Barbara J. Collins, Origin of Polonium Halos, Reports of the National Center for Science Education, 2010, v. 30, Issue 5, pp. 11–16
  • Collins, L. G., 2009, Yes, Noah's Flood May Have Happened but Not over the Whole Earth, Reports of the National Center for Science Education, September–October issue, (in press).
  • Collins, L. G., 1997, Muscovite-garnet granites in the Mojave Desert: Relation to crustal structure of the Cretaceous arc: Comment: Geology, v. 25, p. 187.
  • Collins, L. G., 1993, The metasomatic origin of the Cooma complex in southeastern Australia: Theophrastus Contributions, v. 1, p. 105-112.
  • Collins, L. G., and Davis, T. E., 1992, Origin of high-grade biotite-sillimanite-garnet-cordierite gneisses by hydrothermal differentiation, Colorado; in Augustithis, S. S., ed., High Grade Metamorphics: Athens, Theophrastus Publications, p. 297-338.
  • Collins, L. G., 1989a, Origin of the Isabella pluton and its enclaves, Kern County, California: California Geology, v. 42, p. 53-59.
  • Collins, L. G., 1988b, Myrmekite, a mystery solved near Temecula, Riverside County, California: Geology, v. 41, p. 276-281.
  • Weigand, P. W., Parker, J., and Collins, L. G., 1981, Metamorphic origin of garnets in the Lowe granodiorite, San Gabriel Mtns., California: Transactions of the American Geophysical Union, v. 62, no. 45, p. 1060.
  • Collins, L. G., 1971, Manganese and zinc in amphibolite near the Sterling Hill and Franklin Mines, New Jersey: Economic Geology, v. 66, p. 348-350.
  • Collins, L. G., 1969b, Host rock origin of magnetite in pyroxene skarn and gneiss and its relation to alaskite and hornblende granite: Economic Geology, v. 64, p. 191-201.
  • Collins, L. G., 1966, Finding Rare Beauty In Common Rocks, National Geographic, v. 129, no. 1, January, p. 121-129.
  • Collins, L. G., 1959c, Geology of the magnetite deposits and associated gneisses near Ausable Forks, New York: unpublished Ph.D. thesis, University of Illinois, 147 p.

References

  1. ↑ "September Promotions Announced for 39 State College Educators". Los Angeles Times. 1962-05-20. p. SF3.
  2. ↑ "VSC Faculty Joins Protest of State 'Bias'". Los Angeles Times. 1966-11-17. p. SF1.
  3. ↑ Collins, L. G., 1988b, Myrmekite --- A mystery solved near Temecula: California Geology, v. 41, no. 12, p. 276-281.
  4. ↑ Article index
  5. ↑ Evolution of a layered diorite-gabbro to become a layered quartz monzonite-granodiorite in the Wanup pluton near Sudbury, Canada Archived 2009-07-05 at the Wayback Machine.
  6. ↑ Metasomatic origin of the Cooma Complex in southeastern Australia
  7. ↑ Articles in opposition to creationism
  8. ↑ Salt, Pepper and Blah
  9. ↑ Christianity and science - are they contradictory?
  10. ↑ A challenge from a person holding a Th.D degree
  11. 1 2 Collins, L. G., 2009, Yes, Noah's Flood May Have Happened but Not over the Whole Earth, Reports of the National Center for Science Education, September–October issue
  12. ↑ Nov/Dec 2012 issue of the Reports of the National Center for Science Education
  13. ↑ Polonium halos and myrmekite in pegmatite and granite
  14. ↑ Gentry, R. V., 1988, Creation's Tiny Mystery, 2nd ed., Earth Science Associates, Knoxville, 348 pages.

Further reading

  • Hunt, C. W.; Collins, L. G.; Skobelin, E. A. (1992). Expanding Geospheres. Polar Publishing. p. 421. ISBN 0-9694506-1-3.
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