[ { "id": "authors:94ae5-bmd22", "collection": "authors", "collection_id": "94ae5-bmd22", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-145554089", "type": "book_section", "title": "Redistribution of Strontium and Rubidium Isotopes during Metamorphism, World Beater Complex, Panamint Range, California", "author": [ { "family_name": "Lanphere", "given_name": "M. A.", "clpid": "Lanphere-M-A" }, { "family_name": "Wasserburg", "given_name": "G. J. F.", "orcid": "0000-0002-7957-8029", "clpid": "Wasserburg-G-J" }, { "family_name": "Albee", "given_name": "A. L.", "clpid": "Albee-A-L" }, { "family_name": "Tilton", "given_name": "G. R.", "clpid": "Tilton-G-R" } ], "contributor": [ { "family_name": "Craig", "given_name": "H.", "clpid": "Craig-Harmon" }, { "family_name": "Miller", "given_name": "S. L.", "clpid": "Miller-S-L" }, { "family_name": "Wasserburg", "given_name": "G. J.", "clpid": "Wasserburg-G-J" } ], "abstract": "An earlier Precambrian gneiss dome in the Panamint Range of California and its\nmantle of later Precambrian and Paleozoic rocks have been metamorphosed in late\nMesozoic time. Uranium-lead analyses of zircons indicate the primary age of the older\ngneiss to be about 1800 m.yrs and the age of a younger cross-cutting granite to be about\n1300 to 1400 m.yrs. Potassium-argon ages on biotite give ages ranging from 103-130\nm.yrs. Rubidium-strontium isotopic studies of all the constituent minerals and their\nassociated total rocks yielded biotite-total rock isochrons indicating ages ranging from\n64 to 156 m.yrs. All of the total rock ages deviate considerably from the apparent\nprimary age indicated by the zircon ages. The intercept values of Sr^(87)/Sr^(86) for the isochrons\nfrom the various rocks range from 0.85 to 1.08.\n\nNearly complete isotopic homogenization of strontium has occurred locally during\nthis metamorphic episode for all mineral systems except apatite and muscovite. The\n\"total rock systems\" were open in some cases, including samples as large as 85 kg. There\nis obvious mineralogic and field evidence for metamorphism in the mantling sediments\nbut no evidence for gross recrystallization and mobilization in either the mantling\nrocks or the underlying gneiss and granite. Even though original textures and structures,\nboth sedimentary and igneous are preserved, the observed homogenization of strontium\nindicates that extensive migration of strontium occurred and affords a sensitive test\nof metamorphism. Conditions causing the redistribution of strontium in the gneiss did\nnot lower the lead-uranium ratios of the zircons by more than 30%.\nA basic dike of later Precambrian age was found to contain radiogenic strontium\ndue to partial equilibration with the neighboring gneiss. This rock gives an apparent\nage of 31.4 x 10^9 yrs and presents evidence for strontium transport over a distance of\n5m.", "publisher": "North Holland", "publication_date": "1964" }, { "id": "authors:dtpq4-pvn10", "collection": "authors", "collection_id": "dtpq4-pvn10", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-155025932", "type": "book_section", "title": "Oxygen Isotope Studies on the Origin of Dolomites", "author": [ { "family_name": "Epstein", "given_name": "Samuel", "clpid": "Epstein-S" }, { "family_name": "Graf", "given_name": "Donald L.", "clpid": "Graf-D-L" }, { "family_name": "Degens", "given_name": "Egon T.", "clpid": "Degens-E-T" } ], "contributor": [ { "family_name": "Craig", "given_name": "H.", "clpid": "Craig-Harmon" }, { "family_name": "Miller", "given_name": "S. L.", "clpid": "Miller-S-L" }, { "family_name": "Wasserburg", "given_name": "G. J.", "clpid": "Wasserburg-G-J" } ], "abstract": "Oxygen isotope measurements were made on coexisting dolomite and calcite pairs both\nfrom recent sedimentary deposits and from high temperature laboratory syntheses.\nIn the limited number of synthetic carbonate samples thus far available, it appears that\nthere is an oxygen isotope fractionation between dolomite and calcite, similar to that\nfound in naturally occurring hydrothermal calcite-dolomite pairs. There is a lack of\nsuch fractionation between dolomite and calcite in young sedimentary deposits. It is\ntherefore concluded that dolomite is a secondary product resulting from addition of\nmagnesium to existing crystalline CaCO_3, which takes place without an isotopic change\nin the oxygen of the precursor CaCO_3. It is also shown that the O^(18)/O^(16) ratio of dolomite\nis less susceptible to diagenetic reequilibration with surrounding fluids than is that of\ncalcite.", "publisher": "North Holland", "publication_date": "1964" }, { "id": "authors:k8n2p-cxx82", "collection": "authors", "collection_id": "k8n2p-cxx82", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-144826196", "type": "book_section", "title": "On the Abundances of Uranium and Thorium in Solar System Material", "author": [ { "family_name": "Hoyle", "given_name": "F.", "clpid": "Hoyle-Fred" }, { "family_name": "Fowler", "given_name": "William A.", "clpid": "Fowler-W-A" } ], "contributor": [ { "family_name": "Craig", "given_name": "H.", "clpid": "Craig-Harmon" }, { "family_name": "Miller", "given_name": "S. L.", "clpid": "Miller-S-L" }, { "family_name": "Wasserburg", "given_name": "G. J.", "clpid": "Wasserburg-G-J" } ], "abstract": "In this chapter we shall review the theoretically calculated abundances\nof U, Th relative to Si for solar system material, our arguments being\nbased primarily on nuclear theory and only in part on experimental\ndeterminations from meteorites. In fact our estimates for U, Th abundances\nturn out about four times greater than direct determinations for\nchondritic meteorites. They are indeed so great as to raise geophysical\nquestions as to whether such quantities can be accommodated inside\nthe earth.", "publisher": "North Holland", "publication_date": "1964" }, { "id": "authors:42s0c-sh677", "collection": "authors", "collection_id": "42s0c-sh677", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160126-091610550", "type": "book_section", "title": "Characteristics of Lead Isotope Evolution on a Continental Scale in the Earth", "author": [ { "family_name": "Patterson", "given_name": "Clair", "clpid": "Patterson-C-C" } ], "contributor": [ { "family_name": "Craig", "given_name": "H.", "clpid": "Craig-Harmon" }, { "family_name": "Miller", "given_name": "S. L.", "clpid": "Miller-S-L" }, { "family_name": "Wasserburg", "given_name": "G. J.", "clpid": "Wasserburg-G-J" } ], "abstract": "Recent investigations of lead isotopes in oceanic sediments, beach and river sands, and\noceanic volcanics are reviewed from one comprehensive point of view: relatively large\namounts of uranium and small amounts of lead have been continuously transported from\nthe interior of the earth to an outer protocontinental layer throughout geologic time;\ncontinental segments were formed at different times from this layer, but such activity\nwas largely confined to the interval 3500 m.yrs ago to 2500 m.yrs ago; uranium is\nenriched in the surface rocks of the continents by magmatic activity, but such rocks\nare well-mixed with uranium depleted material throughout a depth of a few tens of\nkm during orogeny, so that lead isotope effects resulting from uranium enrichment can\nonly be seen during aging in the quiet period following orogeny; the uranium-poor\nsource layers of continental basalts, on the other hand, are not well-mixed with the\noverlying uranium-rich layers because leads in young continental basalts are relatively\nnon-radiogenic, showing the effects of aging in relatively isolated uranium poor chemical\nsystems; oceanic basalts are moderately radiogenic and originate from moderately\nuranium-rich materials (the protocontinents).", "publisher": "North Holland", "publication_date": "1964" }, { "id": "authors:40fqt-xg217", "collection": "authors", "collection_id": "40fqt-xg217", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-155826850", "type": "book_section", "title": "Comparison of Oxygen Isotope Analyses of Tektites, Soils, and Impactite Glasses", "author": [ { "family_name": "Taylor", "given_name": "Hugh P., Jr.", "clpid": "Taylor-H-P-Jr" }, { "family_name": "Epstein", "given_name": "Samuel", "clpid": "Epstein-S" } ], "contributor": [ { "family_name": "Craig", "given_name": "H.", "clpid": "Craig-Harmon" }, { "family_name": "Miller", "given_name": "S. L.", "clpid": "Miller-S-L" }, { "family_name": "Wasserburg", "given_name": "G. J.", "clpid": "Wasserburg-G-J" } ], "abstract": "New oxygen isotope analyses of tektites from various localities were made, including\ntwo philippinites from Isabela, Philippine Islands, one of which contains small Ni-Fe\nspherules (CHAO and others [1961]); a billitonite; a Muong Nong-type tektite, as well as\na normal type, from Phang Daeng, Thailand; a Georgia tektite; and seven bediasites.\nThe total range in \u03b4-values for 24 tektites from widely separated occurrences is 8.9 to\n10.8 per mil, relative to mean ocean water. Eight isotopic analyses of bediasites exhibit\na good correlation with index of refraction, density, and SiO_2 content. The higher the\nO(^18)/O^(16) ratio the lower is the SiO_2 content. The other analyzed tektites do not show this\ncorrelation.\nThirteen randomly selected soils of various types (11 from the U.S.A.) have \u03b4-values\nranging from 10.0 to 15.9 per mil, and a series of samples from a soil profile in Georgia\nshow a progressive increase of 5 per mil from the fresh granite up to the clay-rich B\nzone; sandy A zone material is 3 per mil lower in O(^18)/O^(16) than the immediately underlying B zone. Two soil samples were selected for fusion experiments; it was found that\nmelting increased the O(^18)/O^(16) ratios of soils by about 1 per mil. Inasmuch as it would\nrequire a 3.5-4.0 per mil lowering of O(^18)/O^(16) in soils to bring them into the tektite range,\nthey appear to be unlikely parent materials for tektites.\nFour samples of impactite glass (Ries-2 samples, Wabar, and Henbury) give \u03b4 -values\nof 7.9, 9.0, 12.7, and 14.4. Dense, clean glass from the Hies Kessel, the sample which\nmost closely resembles tektite glass in appearance, gave the smallest \u03b4-value. The\noxygen isotope data suggest that tektites are either fused terrestrial granitic rocks\n(with changed chemical composition), or they are extraterrestrial.", "publisher": "North Holland", "publication_date": "1964" }, { "id": "authors:44748-s2b35", "collection": "authors", "collection_id": "44748-s2b35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160125-154206535", "type": "book_section", "title": "Sr/Ca Ratio of Skeletal Aragonites from the Recent Marine Biota at Palau and from Fossil Gastropods", "author": [ { "family_name": "Lowenstam", "given_name": "Heinz A.", "clpid": "Lowenstam-H-A" } ], "contributor": [ { "family_name": "Craig", "given_name": "H.", "clpid": "Craig-Harmon" }, { "family_name": "Miller", "given_name": "S. L.", "clpid": "Miller-S-L" }, { "family_name": "Wasserburg", "given_name": "G. J.", "clpid": "Wasserburg-G-J" } ], "abstract": "The Sr/Ca ratios were determined from skeletal aragonites of the marine biota and sea\nwater from Palau, South Pacific, where the temperature and Sr/Ca ratio of the waters\nare constant throughout the year. The Sr/Ca ratios of the aragonites from all groups of\norganisms except those of the higher Mollusca are similar or slightly higher than those\nin sea water. In samples from all phyla with high Sr/Ca ratios, the crystal chemistry is\nconsidered the primary control of the Sr/Ca ratios from their skeletal aragonites, whereas\nphysiologic control by the organisms is considered as a second order effect. In agreement\nwith data in the literature, the Sr/Ca ratios from the skeletal aragonites of the\nmore advanced Mollusca were found to be low and indicate strong discrimination\nagainst Sr relative to Ca in the carbonate as compared to sea water, and this is related\nto physiologic control by the organisms.\nThe measured Sr/Ca ratios from aragonitic shells of fossil gastropods from Cretaceous\nand Pennsylvanian deposits are shown to be higher the older the fossils. The increase\nin Sr/Ca ratios in the gastropod shells with increase in geologic age is toward the Sr/Ca\nratio in present day sea water. It is suggested that this reflects biochemical evolutionary\nchanges of increased discrimination by the gastropod against Sr relative to Ca from\nthe late Paleozoic to the present.", "publisher": "North Holland", "publication_date": "1964" } ]