Late Cenozoic tephrostratigraphy offshore the southern Central American Volcanic Arc: 2. Implications for magma production rates and subduction erosion
Late Cenozoic tephrostratigraphy offshore the southern Central American Volcanic Arc: 2. Implications for magma production rates and subduction erosion
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中美洲南部火山弧近海的晚新生代地层地层学：对岩浆生产率和俯冲侵蚀的 2 个影响
DOI：
10.1002/2016gc006504
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发表时间：
2016
期刊：
影响因子：
3.7
通讯作者：
Alvarado
中科院分区：
文献类型：
--
作者：
Schindlbeck;Kutterolf;Freundt;Straub;Vannucchi;Alvarado
中美洲近海的太平洋钻探地点为研究大爆发火山作用的演化和大陆边缘回到新近纪的大地构造演化提供了独特的机会。在第一部分中，由Tephrochono地层学建立的Tephra层的时间分布表明，哥斯达黎加和尼加拉瓜火山弧在过去8个月内几乎连续地出现了高度爆炸性的喷发记录。广泛分布的海洋火山喷发层构成了各自喷发的火山喷发体积和块体的主要部分，从而提供了对中美洲南部火山弧(CAVA)沿线大规模爆发的区域和时间变化的洞察。我们在科迪勒拉中心观察到了三次增强的火山喷发脉冲，分别发生在0-1 Ma、瓜纳卡斯特1-2 Ma和尼加拉瓜西部3 Ma。长期平均，最小喷发岩浆流量(单位弧长)为∼0.017 g/ms。受Ar-Ar测年和陆源冰盖年代相关的制约，Tephra年龄得到了与俯冲侵蚀构造过程有关的四个显著的峰值沉积速率阶段的夹层远洋沉积物的时变积累速率。奥萨附近>；2.3 Ma的峰值速率与开始于2.91 ± 0.2 3 Ma的科科斯山脊俯冲作用有关，这是由巴尔瓦火山1.42 Ma的OIB地球化学信号延迟出现的1.5Myr所推断的。随后的构造重新安排可能涉及瓜纳卡斯特段的地壳伸展，这有利于2-1 Ma异常大规模的流纹岩生产。
Pacific drill sites offshore Central America provide the unique opportunity to study the evolution of large explosive volcanism and the geotectonic evolution of the continental margin back into the Neogene. The temporal distribution of tephra layers established by tephrochonostratigraphy in Part 1 indicates a nearly continuous highly explosive eruption record for the Costa Rican and the Nicaraguan volcanic arc within the last 8 Myr. The widely distributed marine tephra layers comprise the major fraction of the respective erupted tephra volumes and masses thus providing insights into regional and temporal variations of large‐magnitude explosive eruptions along the southern Central American Volcanic Arc (CAVA). We observe three pulses of enhanced explosive volcanism between 0 and 1 Ma at the Cordillera Central, between 1 and 2 Ma at the Guanacaste and at >3 Ma at the Western Nicaragua segments. Averaged over the long‐term the minimum erupted magma flux (per unit arc length) is ∼0.017 g/ms. Tephra ages, constrained by Ar‐Ar dating and by correlation with dated terrestrial tephras, yield time‐variable accumulation rates of the intercalated pelagic sediments with four prominent phases of peak sedimentation rates that relate to tectonic processes of subduction erosion. The peak rate at >2.3 Ma near Osa particularly relates to initial Cocos Ridge subduction which began at 2.91 ± 0.23 Ma as inferred by the 1.5 Myr delayed appearance of the OIB geochemical signal in tephras from Barva volcano at 1.42 Ma. Subsequent tectonic re‐arrangements probably involved crustal extension on the Guanacaste segment that favored the 2–1 Ma period of unusually massive rhyolite production.
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影响因子：
5.8
作者：
J. Schindlbeck;S. Kutterolf;A. Freundt;S. Straub;Kuo‐Lung Wang;M. Jegen;S. Hemming;A. Baxter;M. I. Sandoval
通讯作者：
J. Schindlbeck;S. Kutterolf;A. Freundt;S. Straub;Kuo‐Lung Wang;M. Jegen;S. Hemming;A. Baxter;M. I. Sandoval
中美洲太平洋近海普林尼弧火山活动记录：2. 火山灰体积和喷发物
DOI：
--
发表时间：
2008
期刊：
影响因子：
--
作者：
S. Kutterolf;A. Freundt;W. Pérez
通讯作者：
W. Pérez
影响因子：
3.7
作者：
J. Schindlbeck;S. Kutterolf;A. Freundt;G. Alvarado;K.‐L. Wang;S. Straub;S. Hemming;M. Frische;J. Woodhead
通讯作者：
J. Schindlbeck;S. Kutterolf;A. Freundt;G. Alvarado;K.‐L. Wang;S. Straub;S. Hemming;M. Frische;J. Woodhead
洪都拉斯和尼加拉瓜沿中美洲中新世古弧的地球化学变化
影响因子：
5
作者：
B. R. Jordan;H. Sigurdsson;S. Carey;R. Rogers;Jan Ehrenborg
通讯作者：
Jan Ehrenborg
影响因子：
3.5
作者：
I. Saginor;E. Gazel;M. J. Carr;C. Swisher;B. Turrin
通讯作者：
B. Turrin