Na 1 Nachlass Max Horkheimer, 665 - "Research Project on Anti-Semitism" (p. IX 101-IX 112)

Institute of Social Research; "Research Project on Anti-Semitism. General Statement of Scope of Project, Fields to be investigated, First Assignements, Plan of Operation, Joint Conferences" (15.3.1943), a) Typoskript, 5 Blatt, b) Typoskript, 3 Blatt, c) Typoskript mit handschriftlichen Ergänzungen, 5 Blatt; Institute of Social Research: "Notes on Some Methodological Principles and Some Tentative Assumptions for the Work of the Anti-Semitism Project" (15.3.1943), Typoskript, 3 Blatt; "Project on Anti-Semitism. Excerpt from a letter of D.R. (American Jewish Committee), dated 3/31/43" (31.03.1943), Typoskript mit handschriftlichen Ergänzungen, 2 Blatt; Institute of Social Research: "Research Project on Anti-Semitism. General Statement of Scope of Project, Fields to be investigated, First Assignements etc. Supplement: Los Angeles Group" (26.4.1943), a) Typoskript mit handschriftlichen Ergänzungen, 13 Blatt, b) Typoskript, 13 Blatt, c) Typoskript, 8 Blatt; Heinz Langerhans: "Methods to Evaluate the Attitude of Different Sections of the German Population toward Institutionalized Antisemitism" (6.5.1943), Typoskript mit eigenhändiger Korrektur, 5 Blatt; "Discussion with Messrs. George Mintzer and Newman Levy on present day U.S.A. Antisemitism" (5.3.1943), a) Typoskript, 4 Blatt b) Typoskript mit handschriftlichen Korrekturen, 4 Blatt; Re.: Antisemitism Project. Statement of Expense 15.03.1943 - 15.06.1943, Preliminary Budget 15.06.1943 - 15.03.1944, Aufstellungen für das American Jewish Committee, 15.06.1943, 4 Blatt; Paul Massing: "Some Notes to Fineberg's 'Overcoming Antisemitism'" (16.06.1943), Typoskript, 4 Blatt; "Luncheon with Mr. Hexter. Present: Dr. Pollock, Weil, Gurland, Massing and Mr. Hexter. Purpose: Discussion of S.A. Fineberg's book 'Overcoming Antisemitism'" (17.06.1943), Typoskript, 2 Blatt; "Luncheon with Mr. R.C. Rothschild in the Yale Club", Über Antisemitismus in den USA, 28.6.1943, Typoskript mit handschriftlichen Korrekturen, 1 Blatt; Friedrich Pollock: Memoranden über Besprechungen mit R.C. Rothschild, betreffs Anti-Semitism-Project (September 1943): 1. "Remarks of Mr. Rothschild concerning our Psychological Study in a meeting between him, P. and L." (21.9.1943); 2. "Memorandum on work's progress of Anti-Semitism-Project" (15.09.1943), Typoskript, 1 Blatt; 3. "Meeting R.C. Rothschild and Pollock", (15.09.1943), Typoskript, 2 Blatt; 4. "Memorandum No. 1" (14.09.1943), Typoskript, 1 Blatt; "Memorandum re: Antisemitism Project" (29.10.1943), Typoskript mit handschriftlichen Ergänzungen, 2 Blatt;

Ms.Ff.F.Stoltze 3. 101 - Brief von G. von Guaita an Laura Stoltze

Persönliche Nachrichten

In-situ Iron isotope measurements and mineral compositions from ODP Hole 206-1256D and IODP Hole 335-U1256D

In-situ Fe isotope measurements have been carried out to estimate the impact of the hydrothermal metamorphic overprint on the Fe isotopic composition of Fe-Ti-oxides and Fe-sulfides of the different lithologies of the drilled rocks from IODP Hole 1256D (eastern equatorial Pacific; 15 Ma crust formed at the East Pacific Rise). Most igneous rocks normally have a very restricted range in their 56Fe/54Fe ratio. In contrast, Fe isotope compositions of hot fluids (> 300 °C) from mid-ocean-ridge spreading centers define a narrow range that is shifted to lower delta 56Fe values by 0.2 per mil - 0.5 per mil as compared to igneous rocks. Therefore, it is expected that mineral phases that contain large amounts of Fe are especially affected by the interaction with a fluid that fractionates Fe isotopes during exsolution/precipitation of those minerals. We have used a femtosecond UV-Laser ablation system to determine mineral 56Fe/54Fe ratios of selected samples with a precision of < 0.1 per mil (2 sigma level) at micrometer-scale. We have found significant variations of the delta 56Fe (IRMM-014) values in the minerals between different samples as well as within samples and mineral grains. The overall observed scale of delta 56Fe (magnetite) in 1256D rocks ranges from - 0.12 to + 0.64 per mil, and of delta 56Fe (ilmenite) from - 0.77 to + 0.01 per mil. Pyrite in the lowermost sheeted dike section is clearly distinguishable from the other investigated lithological units, having positive delta 56Fe values between + 0.29 and + 0.56 per mil, whereas pyrite in the other samples has generally negative delta 56Fe values from - 1.10 to - 0.59 permil. One key observation is that the temperature dependent inter-mineral fractionations of Fe isotopes between magnetite and ilmenite are systematically shifted towards higher values when compared to theoretically expected values, while synthesized, well equilibrated magnetite-ilmenite pairs are compatible with the theoretical predictions. Theoretical considerations including beta-factors of different aqueous Fe-chlorides and Rayleigh-type fractionations in the presence of a hydrous, chlorine-bearing fluid can explain this observation. The disagreement between observed and theoretical equilibrium fractionation, the fact that magnetite, in contrast to ilmenite shows a slight downhole trend in the delta 56Fe values, and the observation of small scale heterogeneities within single mineral grains imply that a general re-equilibration of the magnetite-ilmenite pairs is overprinted by kinetic fractionation effects, caused by the interaction of magnetite/ilmenite with hydrothermal fluids penetrating the upper oceanic crust during cooling, or incomplete re-equilibration at low temperatures. Furthermore, the observation of significant small-scale variations in the 56Fe/54Fe ratios of single minerals in this study highlights the importance of high spatial-resolution-analyses of stable isotope ratios for further investigations.