Mesoproterozoic metaplutonic rocks from the southern French Broad massif in southwestern North Carolina preserve Grenville magmatic and metamorphic ages (1.28–1.0 Ga). New in-situ zircon U-Pb measurements from eight basement lithologies, obtained by laser ablation and ion-probe techniques, delineate Elzevirian (1283–1250 Ma), Shawinigan (1191–1126 Ma), and Ottawan (1034–1008 Ma) magmatism and metamorphism. Magmatism produced dominantly calc-alkaline plutons with normative compositions of quartz diorite, quartz monzodiorite, granodiorite, and monzogranite. The majority of magmatism in the field area occurred between ca. 1190 and 1125 Ma, a period correlative to the Shawinigan phase of the Grenville orogeny. Syn- to post-emplacement metamorphism of these units is evidenced by complex zircon U-Pb systematics in all Shawinigan age plutons. Ottawan magmatism, expressed by emplacement of the Max Patch granite and protoliths of the Earlies Gap granitoid gneiss, is less voluminous than Shawinigan magmatism; a difference that mirrors their relative proportions elsewhere in the orogen. Ottawan metamorphism is recorded by growth of new zircon rims around magmatic core domains in several samples and spans a period of ca. 25 m.y. from ca. 1035 to 1010 Ma. The timing of the older and younger magmatic suites from the southern French Broad massif correlate to well-established times of Shawinigan and Ottawan magmatism and metamorphism in other Grenville-age terranes within the U.S. (e.g., Appalachian inliers, Adirondacks).

来自北卡罗来纳州西南部法国布罗德地块南部的中元古代变质岩保留了格伦维尔岩浆和变质时代（1.28-1.0 Ga）。新的原位通过激光烧蚀和离子探测技术获得的八种基底岩性的锆石 U-Pb 测量结果描绘了 Elzevirian (1283–1250 Ma)、Shawinigan (1191–1126 Ma) 和 Ottawan (1034–1008 Ma) 岩浆作用和变质作用。岩浆作用主要产生钙碱性岩体，其成分为石英闪长岩、石英二长闪长岩、花岗闪长岩和二长花岗岩。野外区域的大部分岩浆活动发生在大约 1190 和 1125 Ma，与 Grenville 造山运动的 Shawinigan 阶段相关的时期。所有 Shawinigan 年龄岩体中的复杂锆石 U-Pb 系统学证明了这些单元的同工位变质作用。渥太华岩浆作用，表现为 Max Patch 花岗岩的侵位和 Earlies Gap 花岗片麻岩的原岩，比 Shawinigan 岩浆作用的体积要小；这种差异反映了它们在造山带其他地方的相对比例。渥太华变质作用是通过几个样本中岩浆核心域周围新锆石边缘的生长记录的，跨越了一段时期约。25 我来自加州。1035 至 1010 毫安。来自法国南部布罗德地块的较老和较年轻岩浆组的时间与美国其他格伦维尔时代地体（例如，阿巴拉契亚山脉、阿迪朗达克山脉）中 Shawinigan 和 Ottawan 岩浆作用和变质作用的成熟时间相关。