As it is an ideal location for studying plume–ridge interactions, a clear image of the Icelandic upper mantle structure is necessary. We collect continuous seismic records from 164 stations and extract Rayleigh wave dispersion curves via the frequency-Bessel (F-J) transform method. Based on ambient noise tomography, we provide a new shear-wave velocity model of the Icelandic crust and uppermost mantle, extending to a depth of 120 km. The model is validated by the waveform simulation method and reveals extensive crustal low-velocity zones (LVZs) across both the neovolcanic and nonvolcanic zones of Iceland. These crustal LVZs may be attributed to elevated temperatures, partial melting, and lithological variations. A distinct LVZ beneath a depth of 60 km, mainly on the North American Plate, may correspond to Icelandic plume material. Additionally, hot plume material may be delivered to the crust through low-velocity conduits beneath the spreading mid-ocean ridge. There is a clear contrast between the uppermost mantle low-velocity zones (UMLVZs) in the western region and the uppermost mantle high-velocity zones in the eastern region, which may indicate asymmetric tectonic plates on both sides of the mid-ocean ridge. This asymmetry may be attributed to the multiple eastward jumps of the ridge systems. The eastern high-velocity body, meaning a cooler uppermost mantle than that of the western region, may act as a barrier to obstruct the eastward plume flow. Under plume–ridge interactions, plume material can affect crustal accretion and feed volcanic activity on the surface along the spreading Mid-Atlantic Ridge.

中文翻译：

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环境噪声瑞利波断层扫描揭示冰岛的地震结构


由于它是研究羽流-山脊相互作用的理想位置，因此需要冰岛上地幔结构的清晰图像。我们从 164 个站点收集了连续的地震记录，并通过频率贝塞尔 （F-J） 变换方法提取瑞利波扩散曲线。基于环境噪声层析成像，我们提供了冰岛地壳和最上部地幔的新剪切波速度模型，延伸到 120 公里的深度。该模型通过波形模拟方法进行了验证，并揭示了冰岛新火山和非火山带的广泛地壳低速带 （LVZ）。这些地壳 LVZ 可能归因于高温、部分熔化和岩性变化。深度低于 60 公里的独特 LVZ，主要在北美板块上，可能与冰岛的羽流物质相对应。此外，热羽流物质可能通过扩张的洋中脊下方的低速管道输送到地壳。西部地区最上层的地幔低速带 （UMLVZ） 与东部地区最上层的地幔高速带之间存在明显的对比，这可能表明洋中脊两侧的构造板块不对称。这种不对称性可能归因于山脊系统的多次向东跳跃。东部高速体，即比西部地区更凉爽的最上层地幔，可能成为阻碍羽流向东流动的屏障。在羽流-山脊相互作用下，羽流物质可以影响地壳吸积，并滋养沿不断扩大的大西洋中脊表面的火山活动。