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  • PANGAEA  (442)
  • American Society of Hematology  (180)
  • 2005-2009  (534)
  • 1990-1994  (88)
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  • 1
    Publikationsdatum: 2009-11-20
    Beschreibung: Abstract 717 Purpose: Combined modality treatment consisting of 4 cycles of chemotherapy (CT) followed by involved field radiotherapy (IF-RT) is the standard treatment for early unfavourable HL. In our prior trial for this group of patients (HD8), overall survival (OS) and freedom from treatment failure (FFTF) at 5 years were 91% and 83%, respectively. The HD11 trial thus addressed two major questions: (1) improving outcome by intensifying CT (4xABVD vs. 4xBEACOPPbaseline; Bbas) and (2) defining the best radiation dose (30Gy vs. 20Gy IF-RT). Patients and methods: Between May 1998 and January 2003, 1395 eligible patients aged 16–75 years with untreated early unfavourable stage HL (CS I, IIA with at least one of the risk factors large mediastinal mass (a), extranodal disease (b), elevated ESR (c) or ≥ 3 nodal areas (d); IIB with risk factors c and/or d) were randomized into one of the following 4 treatment arms: 4xABVD + 30Gy (A), 4xABVD + 20Gy (B), 4x Bbas + 30Gy (C) or 4x Bbas + 20Gy (D). Since there are strong indications for an interaction between CT- and RT-doses, a comparison of pooled treatment arms (A+B vs. C+D for comparison of 4×ABVD vs. 4× Bbas and A+C vs. B+D for comparison of 30Gy IF-RT vs. 20Gy IF-RT) would be misleading. Therefore all treatment arms were analysed separately. Results: Patient characteristics were well balanced between the 4 arms (median age 33 years, 49% male, 6% stage I, 29% B-symptoms). CT- and RT-related acute toxicity occurred significantly more often in the arms with the more intensive therapy (CT: 74.1% vs. 51.8%; RT: 12.3% vs. 5.5%). The complete remission rate 3 months after end of therapy was 94.1% for the whole group and did not differ significantly between the 4 arms. The 5-year estimate of FFTF (primary endpoint) is 85.0% (OS 94.5%, PFS 86.0%). Bbas is more effective than ABVD if followed by 20Gy IF-RT (5y-FFTF difference 5.7%, 95%-CI [0.1%; 11.3%]). This effect does not exist in combination with 30Gy IF-RT (5y-FFTF difference 1.6% [-3.6%; 6.9%]). Similar results are observed for the RT-question: After 4 cycles of Bbas, 20Gy is not inferior to 30Gy (5y-FFTF difference -0.1%, 95%-CI [-5.1%; 4.9%]), whereas after 4xABVD, a relevant inferiority of 20Gy cannot be excluded (-4.0% [-9.5%; 1.4%]). Conclusion: A reduction of RT dose from 30Gy to 20Gy IF-RT seems to be justified only in combination with Bbas, but not with a less effective chemotherapy such as 4xABVD. Patients will benefit from an intensified CT such as Bbas only in combination with 20Gy IF-RT but not with 30Gy IF-RT. Disclosures: No relevant conflicts of interest to declare.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 2
    Publikationsdatum: 2005-11-16
    Beschreibung: Background: Combined modality treatment consisting of chemotherapy (CT) followed by involved field radiotherapy (IF-RT) is the standard treatment for early unfavourable Hodgkin’s lymphoma (HL). Despite high complete remission (CR) rates, failures are common. We thus compared the baseline-dose BEACOPP regimen with ABVD and 20 with 30 Gy IF-RT in a prospectively randomized trial (HD11) in an attempt to improve outcome in this group of patients. Methods: Between May 1998 and January 2003, 1570 patients (pts) aged 16–75 with untreated intermediate stage HL (CS I, IIA with risk factors or IIB with elevated ESR and/or ≥3 nodal areas only) were randomized according to a factorial design between 4 cycles of ABVD followed by 30 Gy IF-RT (arm A - standard treatment), 4 ABVD + 20 Gy IF-RT (arm B), 4 baseline-dose BEACOPP + 30 Gy IF-RT (arm C) and 4 baseline-dose BEACOPP + 20 Gy IF-RT (arm D). Results: In the fifth preplaned interim analysis, 1293 pts were evaluable for the chemotherapy comparison and 1274 for the radiotherapy comparison. Patient characteristics were well balanced between the treatment arms. 95% of patients treated reached CR, 2% had pogressive disease, 8% relapsed and the total mortality rate was 4% with no significant differences between treatment arms for either endpoint. The most frequent haematological toxicities during chemotherapy were leucopenia observed in 32% of pts (ABVD: 25%, BEACOPP: 39%) and anemia in 4% of pts (ABVD
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 3
    Publikationsdatum: 2009-11-20
    Beschreibung: Abstract 3281 Poster Board III-1 Introduction: In the two consecutive German CML studies III and IIIA (recruitment periods from 1995 to 2001 and 1997 to 2004), eligible patients were assigned to early HSCT by genetic randomization according to availability of a matched related donor. After randomization, 113 patients of study III (84% of 135) and 144 of study IIIA (87% of 166) were eventually transplanted in first chronic phase (CP) using a related donor. Despite comparable transplantation protocols and most centers participating in both studies, survival probabilities in study IIIA were significantly better, even when adjusted for the established EBMT risk score (Gratwohl et al., Lancet 1998 [1]), p + 0.0097. For further explanation, the German Registry for Stem Cell Transplantation (DRST) and the Swiss Transplant Working Group for Blood and Marrow Transplantation (STABMT) were asked for data support. Patients and Methods: The main sample characteristics of the 257 transplanted CML study patients were also applied to the registry patients: diagnosis of CML between 1994 and 2004, first HSCT with a related donor performed in first CP between 1995 and 2004 at an age between 12 and 65 years, and blood or bone marrow as stem cell sources. Thus, additional data of 582 HSCT patients were retrieved from the two registries. Age, recipient sex, donor sex, time between diagnosis and HSCT, calendar year of HSCT, stem cell source, and HLA matching were investigated as potential predictive factors for survival. Then, a sample of patients with the same risk distribution as the 113 patients of study III was randomly drawn from the registry patients. By application of repeated resampling to this new patient group, bootstrap confidence intervals for survival probabilities at various times after HSCT were extractable. This provided the basis to judge whether the survival in study III could be seen as a typical random representation of a sample with an equivalent risk structure or not. The same method was applied to the 144 patients of study IIIA. Results: The 5-year survival probability of all 839 patients resulted in 73% (229 died). Median follow-up time of living patients was 6.7 years. Due to the characteristic plateau of post-transplant survival probabilities, the predictive influence was judged by the Kaplan-Meier method and the log rank statistic. Also consideration of age and time between diagnosis and HSCT as continuous variables seemed less appropriate than working with categorizations. Furthermore, the previously published cut-points “1 year” for time from diagnosis to HSCT ([1]) and “44 years” for age at HSCT (Maywald et al., Leukemia 2006) were independently confirmed to be the best. Cox model and logistic regression with survival status after 3 years both indicated that age at HSCT, HLA matching, time between diagnosis and HSCT, and calendar year of HSCT had independent statistically significant predictive influence on survival (p 〈 0.05). The first two factors had the strongest effects. Calendar year was only influential when distinction was made between HSCT until and after 1999. All possible combinations of the 4 factors could be summarized in 4 risk groups with significantly different survival probabilities (at 5 years: 87%, 76%, 63%, and 24%). Matched for the risk group distribution of study III [study IIIA], a maximum of 290 [428] registry patients could be drawn. For the 290 [428] patients, 5-year survival was 69% [77%] with a 95% bootstrap confidence interval from 63% to 74% [72% to 81%]. Thus, as for all yearly intervals within the first 5 years, the 5-year survival probabilities of studies III: 65% and IIIA: 79% lied within the corresponding confidence intervals. Conclusions: Along with the registry patients, the study data enabled the identification of age at HSCT, HLA matching, time between diagnosis and HSCT, and calendar year of HSCT as factors with independent predictive impact on survival which led to 4 risk groups with statistically significantly different survival probabilities. More favorable-risk patients in study IIIA stood for a better transplantation strategy. In consideration of these different risks, the survival probabilities in both studies did not significantly vary from those of registry samples with matched risk structures. Accordingly, an improved transplantation strategy along with random variation could be considered as an explanation of the significantly different survival probabilities between the two studies. Disclosures: Haferlach: MLL Munich Leukemia Laboratory: Equity Ownership. Hochhaus:Novartis, Bristol-Myers Squibb: Research Funding. Hasford:Novartis: Research Funding. Gratwohl:AMGEN, Roche, Bristol-Myers Squibb, Novartis, Pfizer: Research Funding; Novartis: Consultancy. German CML Study Group:Kompetenznetz Leukämie, European Leukemia Net, Roche, Essex, AMGEN: Research Funding.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 4
    Publikationsdatum: 2006-11-16
    Beschreibung: The preceding trial HD9 had shown a significant superiority for escalated BEACOPP (EB) for failure-free survival (FFTF) and overall survival (OS) over COPP/ABVD or baseline BEACOPP (BB) (each 8 cycles). HD12 aimed to de-escalate chemotherapy by comparing 8 cycles EB with 4 cycles EB plus 4 cycles BB, with or without consolidatory 30 Gy radiation (RT) to initial bulky and residual disease. A total of 1661 patients aged 16–65 with HL in stage IIB (large mediastinal mass and/or E-lesions) or stage III-IV were randomised from 9/1999-1/2003 according to a factorial design between: 8EB + RT, 8EB no RT, 4EB+4BB + RT, 4EB+4BB no RT. A central diagnostic panel reviewed CT images after completion of chemotherapy independent of randomisation arm, and prescribed RT in selected cases. In the fifth analysis of HD12 (5/2006), 94% of all 1593 eligible randomised patients were evaluable, including 1498 for the chemotherapy comparison and 1449 for the radiotherapy comparison. Patient characteristics were very similar for all 4 arms. Radiation was given in arms with planned RT in 65%, in arms with no planned RT in 10%. 93% of all patients reached a complete remission, 2.2% suffered early progression, 4.6% relapsed and 8.2% died with a median folllow-up time of 48 months. Death due to acute toxicity was 3.2% (sepsis, cardiac, pulmonary, infection), with 21 such deaths in the 8EB arms and 27 in the 4EB+4BB arms. Secondary neoplasias were observed in 55 patients (3.7%): 14 AML/MDS, 12 NHL and 29 solid tumors/others. Four-year Kaplan-Meier estimates for arm pairs according to the factorial design were: 4 year rates, %(95% CI) 8EB vs. 4EB+4BB with RT vs. without RT FFTF 88(86–91) 86(83–89) 91(89–93) 88(86–91) OS 93(91–95) 91(89–93) No significant differences were observed when comparing treatments according to the sequential analysis plan (N.B. 10% received RT in arms ‘without RT’). The final analysis, scheduled when 80% of patients have 5 years follow-up, must be awaited before final conclusions can be drawn.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 5
    Publikationsdatum: 2009-11-20
    Beschreibung: Abstract 716 Background: There has been an ongoing debate on the best treatment for patients with early favourable Hodgkin lymphoma (HL). Open questions include the choice between combined modality treatment or chemotherapy only, the number of chemotherapy cycles needed and the optimal radiation dose. The GHSG thus conducted a randomized study for patients with early-stage favourable Hodgkin lymphoma (HD10) in which these questions were addressed. Methods: HD10 was an international prospectively randomized multicenter trial comparing 2 and 4 cycles of ABVD as well as 20Gy or 30Gy involved field radiotherapy (IFRT) in a 2 × 2 statistical design. Between 5/1998 and 1/2003, a total of 1370 patients from 329 centers were randomized into four arms: 4 × ABVD + 30Gy; 4 × ABVD + 20Gy; 2 × ABVD + 30Gy; 2 × ABVD + 20Gy. All patients had their initial histology reviewed by a lymphoma expert panel. Documentation was complete in more than 99,1% of cases for this final analysis. Results: Patients were equally balanced for age, gender, stage, histology, performance status and risk factors between arms. There were significant differences in major toxicity (WHO grade III/IV) between 4 × ABVD and 2 × ABVD in the overall number of events (52% vs 33%) including leukopenia (24% vs 15%) and hair loss (28% vs 15%). In terms of radiation dose, there also was a difference in toxicity between 30Gy and 20Gy IFRT (all events: 8.7% vs 2.9%), dysphagia (3% vs 2%), mucositis (3.4% vs 0.7%). Complete remission was achieved in 97% of patients treated with 4 × ABVD, 97% with 2 × ABVD, 99% after 30Gy and 97% after 20Gy. With a median follow-up of 79–91 months, there was no significant difference between 4 × ABVD and 2 × ABVD in terms of overall survival at 5 years (OS: 4 × ABVD 97.1%; 2 × ABVD: 96.6%), freedom from treatment failure (FFTF: 93.0% vs 91.1%) and progression free survival (PFS: 93.5% vs 91.2%). For the radiotherapy question, there were also no significant differences between patients receiving 30Gy IFRT and those with 20Gy IFRT in terms of OS (97.6% vs 97.5%), FFTF (93.4% vs 92.9%) and PFS (93.7% vs 93.2%), respectively. Importantly, there was also no significant difference in terms of OS, FFTF and PFS when all four arms were compared. Conclusion: Two cycles of ABVD followed by 20Gy IFRT is the new GHSG standard of care for Hodgkin patients in early favourable stages. Disclosures: No relevant conflicts of interest to declare.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 6
    Publikationsdatum: 2005-11-16
    Beschreibung: Combined modality treatment is regarded as standard by most study groups for patients with early-stage Hodgkin’s lymphoma (HL). However, the optimal chemotherapy, the number of cycles needed and the optimal radiotherapy dose is still unclear. The GHSG thus conducted a randomised study for patients with early stage favourable Hodgkin’s lymphoma (HD10) in which these questions were addressed. A total of 1370 patients were randomised from 5/1998 to 1/2003 between two or four cycles of ABVD and independently to 20Gy or 30Gy involved field (IF) radiotherapy. For the second interim analysis at a median follow up of 28 months, 847 patients were available. Patients were equally balanced for age, gender, stage, histology, performance status and risk factors. Compared with two cycles, there was more toxicity in patients receiving four cycles of ABVD for leucopenia, hair loss and infection. Concerning radiotherapy dose, there was more toxicity associated with 30Gy for dysphagia, mucositis and leucopenia. The rate of complete remissions ranged between 98% and 99% with no significant differences among treatment arms. Freedom from treatment failure (FFTF) and overall survival showed no differences between the four treatment arms. The curves for overall survival and FFTF were nearly superimposable for all four arms. This analysis suggests that 2 chemotherapy cycles with involved field radiotherapy may be sufficient for patients with early favourable HL, but a reliable assessment must await the final analysis including all randomised patients and with adequate follow-up. The results of the third interim analysis (10/2005) including 1110 patients with a median follow up of more than 3 years will be presented.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 7
    Publikationsdatum: 2008-11-16
    Beschreibung: Purpose: The GHSG HD9 trial had established BEACOPP escalated (BE) as new standard of care for advanced-stage HL patients by showing significant superiority in terms of failure-free survival (FFTF) and overall survival (OS) over COPP/ABVD and BEACOPP baseline (BB) (each 8 cycles). The successor study, HD12, evaluated a possible reduction in toxicity by comparing 8 cycles of BE with 4 cycles BE followed by 4 cycles BB. The second question in this trial related to the need of additional radiotherapy (RT) to initial bulk and residual disease. Patients and methods: HL patients in stage IIB with large mediastinal mass and/or E-lesions or stage III/IV were randomised according to a 2×2-factorial design between: 8BE + RT, 8BE no RT, 4BE+4BB + RT, 4BE+4BB no RT. Reviewing CT-images before and after chemotherapy treatment, fields for RT were centrally planned by a multidisciplinary diagnostic panel blinded for the randomisation arm. Primary endpoint of the trial was FFTF. Between 9/1999 and 1/2003, a total of 1,670 patients aged 16–65 were randomized. For this final analysis at a median follow up of 78 months, 99 patients were excluded (42 HL not confirmed, 20 revision of stage, 20 no study treatment or documentation, 17 others) resulting in 1,571 eligible patients. Results: Patient characteristics in the 4 groups were comparable with 49% of patients in stage III, 35% in stage IV, 68% reporting B-symptoms and 28% having a large mediastinal tumor. An IPS of 3 or greater was reported for 38% of patients, predominant histology was nodular sclerosis with 57% of cases. Treatment-related toxicity of WHO grade III/IV was observed in 97% of patients. Most prominent differences between pooled chemotherapy arms were anemia (65% 8BE vs 51% 4BE+4BB) and thrombopenia (65% vs 51%). Treatment outcome: complete remission 92.4%; early progression 2.2%; progression/relapse 7.8% (6.6% and 8.5%). A total of 156 (9.9%) deaths (72 vs 84) have been observed (22 vs 32 acute or salvage treatment toxicity; 15 vs 24 HL; 22 vs 13 secondary neoplasia). Most treatment related deaths occurred in the 〉60 years age group, the first 4 cycles and the IPS〉 3 RF groups. Secondary neoplasias were observed in 77 patients (4.9%): AML/MDS 1.5% vs 1.4%, NHL 1.4% vs 0.6% and solid tumors/others 2.5% vs 2.3%. At 5 years, OS was 91%, FFTF 85.5% and progression free survival (PFS) 86.2% (Kaplan- Meier estimates). Estimates for the difference at 5 years are 1.8% for OS, 2.3% for FFTF and 2.7% for PFS favoring BE. However, there was no statistical difference between 8x BE and 4BE+4BB in all outcome parameters (p〉0.19, log rank test). There is also no significant difference between the RT or no-RT arms in this study with the caveat that a number of high-risk patients receiving RT based on the blinded panel decision. Conclusion: The adoption of 4BE+4BB as a new standard in the future GHSG studies will depend on a refined analysis of the total data set and will be presented.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 8
    Publikationsdatum: 2006-11-16
    Beschreibung: Introduction: Lymphocyte predominant Hodgkin lymphoma (LPHL) differs in histological and clinical presentation from classical Hodgkin lymphoma (cHL). Treatment of LPHL patients using standard approaches leads to complete remission (CR) in more than 95% of patients. However, differences in terms of relapse rates, overall survival (OS) and freedom from treatment failure (FFTF) between LPHL and cHL patients were suggested by a recent intergroup analysis. To obtain a more comprehensive picture, we reviewed all LPHL-cases registered in the GHSG database comparing patient characteristics and treatment outcome with cHL patients. Patients and methods: We retrospectively analyzed 8298 HL patients treated within the GHSG trials (HD4 to HD12). 394 patients had LPHL and 7904 cHL. From 394 LPHL patients, 63% were in early favorable stage, 16% in early unfavorable and 21% in advanced stage of disease. Of the 7904 cHL patients analyzed, 22% were in early favorable, 39% in early unfavorable and 39% in advanced stages. 9% of LPHL patients had B symptoms compared to 40% in cHL patients. Results: 91% LPHL vs. 86% cHL patients in early favorable stages, 86% vs. 83% in early unfavorable and 79% vs. 75% in advanced stages reached CR/CRu. 0.3% LPHL patients developed progressive disease (PD) compared to 3.7% cHL patients. The relapse rate of LPHL patients was very similar to cHL (8.1% vs. 7.9%). There were 2.5% secondary malignancies in LPHL and 3.7% in cHL patients. 4.3% LPHL patients and 8.8% cHL patients died. The FFTF rates for LPHL and cHL patients at a median observation of 41 or 48 months were 88% and 82% (p=0.0093), respectively. The OS for LPHL and cHL patients was 96% and 92%, respectively (p=0.0166). The analysis between LPHL stages showed significant differences in FFTF (p=0.0239). According to a multiple Cox-regression analysis, advanced stage (p=0.0089) and lymphocytes 〈 8% of white cell count was shown as negative prognostic factors for FFTF and age ≥ 45 years (p=0.008) as negative factor for OS in LPHL patients. Hb value 〈 10.5 g/dl was shown as negative factor for both, FFTF and OS (p=0.0125, p=0.0002). Conclusion: This is the largest analysis comparing LPHL and cHL patients. We found differences in FFTF and OS rates between both groups and differences in FFTF between LPHL stages. New treatment protocols for LPHL patients with reduced intensity schedules are to be discussed.
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 9
    Publikationsdatum: 2009-11-20
    Beschreibung: Abstract 719 Introduction: The standard of care for adolescent Hodgkin lymphoma (HL) patients is undefined, particularly the choice between adult and pediatric protocols. We thus analyzed and compared risk factors, outcome and incidence of secondary malignancies in adolescents and young adults treated within study protocols of the German Hodgkin Study Group (GHSG) to evaluate whether adolescents represent a distinct patient group. Patients and Methods: 3785 patients of all stages treated within the second (HD4-HD6, 1988-1993) and third (HD7-HD9, 1993-1998) trial generation of the GHSG were retrospectively analyzed. 557 patients were adolescents aged 15 to 20 and 3228 patients were young adults aged 21 to 45. Treatment consisted of chemo- and/or radiotherapy. Results: The risk factors large mediastinal mass (more than 1/3 of the maximum intrathoracic diameter) and involvement of three or more lymph node areas were more common in adolescents (30.2% vs. 20.9% and 67.7% vs. 58.7%, respectively, p
    Print ISSN: 0006-4971
    Digitale ISSN: 1528-0020
    Thema: Biologie , Medizin
    Standort Signatur Erwartet Verfügbarkeit
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  • 10
    facet.materialart.
    Unbekannt
    PANGAEA
    In:  Supplement to: Müller, Daniel W; Müller, Paul A; McKenzie, Judith A (1990): Strontium isotopic ratios as fluid tracers in Messinian evaporites of the Tyrrhenian Sea (western Mediterranean Sea). In: Kastens, KA; Mascle, J; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 107, 603-614, https://doi.org/10.2973/odp.proc.sr.107.194.1990
    Publikationsdatum: 2024-01-09
    Beschreibung: Strontium isotopic ratios of gypsums recovered from upper Miocene (Messinian) evaporites at ODP Leg 107 Holes 652A, 653B, and 654A (Tyrrhenian Sea) are lower than expected. The values for the Messinian balatino-like gypsum, single gypsum crystals, and anhydrites range from 0.70861 to 0.70886 and are approximately 25 * 10**-5 less than would be expected for evaporites precipitated from Messinian seawater (0.70891-0.70902). Pre-evaporitic planktonic foraminifers from Hole 654A show variable degrees of dolomitization and 87Sr/86Sr values that irregularly decrease upward from normal marine values approximately 81m below the lowest evaporite occurrence. This suggests diagenetic alteration by advecting interstitial water with a low 87Sr/86Sr ratio or that the lower Sr isotopic ratios for the Messinian evaporites could have resulted from a greater influence of fresh water on the Sr isotopic composition of the desiccating Tyrrhenian Sea. Fluctuations of the 87Sr/86Sr-ratio for evaporites in the sedimentary cycles recognized for Holes 653B and 654A, the generally low Sr isotopic ratio of river water entering the Mediterranean Sea, and the presence of dwarf marine microfossils suggest that the 87Sr/86Sr ratio of the evaporites responded to hydrologic variations in a very restricted basin with variable rates of marine and fresh water input. The strontium isotopic ratios of the Messinian anhydrites from the proposed lacustrine sequence at Hole 652A fall in the same range as the marine evaporites from Holes 654A and 653B. This suggests a common or similar origin of the brines at the three locations. The complex depositional and hydrologic conditions in the Mediterranean during the Messinian salinity crisis preclude the use of Sr isotopic values from the evaporites for stratigraphic correlation and dating. They are, however, very useful in the interpretation of the depositional history of the basin. General calculations assuming a closed system suggest that the 87Sr/86Sr ratio of Messinian seawater (-0.7090) could be reduced to that of the evaporites (-0.7087) by mixing with fresh water (e.g., Nile River) in times of 10**4 to 10**5 yr.
    Schlagwort(e): 107-652A; 107-653B; 107-654A; DRILL; Drilling/drill rig; Joides Resolution; Leg107; Ocean Drilling Program; ODP; Tirreno Sea
    Materialart: Dataset
    Format: application/zip, 6 datasets
    Standort Signatur Erwartet Verfügbarkeit
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