We use core reflected ScS waves sensitive to a broad region of the core-mantle boundary beneath Hawaii to create the first high-resolution map of the Hawaiian ultralow-velocity zone (ULVZ). Positive ScS-S differential times are used to identify regions of strong slow velocity anomalies in the lowermost mantle, and the presence of pre/post-cursors around the main ScS phase confirms the sharp top of a basal ULVZ layer. Pre/post-cursor arrivals are mapped into a volume across their region of sensitivity to produce a detailed image of ULVZ morphology. The variability observed across the ULVZ can be interpreted in terms of varying height or velocity reduction, but the large range of velocity variations required to explain observations suggests that most variability reflects varying layer thickness.

The Hawaiian ULVZ is observed to be a large-scale regional feature of varying height (∼5-25 km) extending across a wide area along the edge of the Pacific large low-velocity province (LLVP). Variability in previous models of the Hawaiian ULVZ can be explained by studies imaging different parts of this strongly variable, large-scale feature. Maximum ULVZ thicknesses (no taller than 30 km) are found in a flat-topped, steep-sided region on the order of 1000 km in diameter located west of Hawaii. This feature is coincident with the previously identified Hawaiian mega-ULVZ, and is interpreted to represent the root of the Hawaiian plume, which is offset from the volcanic surface expression. A tall, asymmetric ridge of ULVZ material is observed to the east of Hawaii. Both regions of maximum ULVZ heights are bounded by the Pacific LLVP to the south, and fast seismic velocity anomalies interpreted as slab remnants to the north. This points to a potential geodynamical scenario where dense ULVZ material is pushed by subducted slab remnants into thicker piles against LLVP margins.

我们使用对夏威夷以下岩心-地幔边界的宽阔区域敏感的核心反射ScS波来创建夏威夷超低速带（ULVZ）的第一张高分辨率地图。ScS-S的正时差用于确定最下部地幔中强烈的慢速异常区域，并且主ScS相周围的前/后光标的存在确认了基底ULVZ层的锋利顶部。光标之前/之后的到达被映射到其敏感区域中的体积中，以生成ULVZ形态的详细图像。可以用变化的高度或速度降低来解释在ULVZ上观察到的变化，但是解释观测结果所需的大范围速度变化表明，大多数变化反映了变化的层厚度。

夏威夷ULVZ是沿太平洋大型低速省（LLVP）的边缘分布在宽阔区域的高度变化（〜5-25 km）的大型区域特征。夏威夷ULVZ先前模型中的可变性可以通过对这种强烈变化的大规模特征的不同部分进行成像研究来解释。在位于夏威夷西面的直径约1000 km的平顶陡峭区域中，可以找到最大ULVZ厚度（不超过30 km）。此功能与先前确定的夏威夷巨型ULVZ一致，并被解释为代表夏威夷羽状体​​的根部，该根系与火山表面的表达有所偏移。在夏威夷以东观察到一个高高的，不对称的ULVZ材料脊。ULVZ最大高度的两个区域都以太平洋LLVP为界，向南，快速地震速度异常被解释为北部的板状残余。这表明了潜在的地球动力学场景，其中厚实的ULVZ材料被俯冲的平板残余物推向LLVP边缘的较厚桩体。