CAREER: Deciphering the Tectonic History of the Transantarctic Mountains and the Wilkes Subglacial Basin

智力价值：要了解南极洲的地球动力学发展，必须确定横贯北极的山脉(TAMS)和威尔克斯冰下盆地(WSB)的起源。目前对TAMS和WSB之下的地壳厚度和地震速度结构的限制是有限的，这导致了为解释它们的形成而提出的相互竞争的地质模型的不确定性。国际和平研究所建议通过新的地震部署--横贯北极山脉北部网(TAMNNET)--横跨北部TAMS和WSB的15个台站阵列--来扩大对这一地区的调查，这将填补地震覆盖范围的一个主要空白。TAMNNET的数据将与以前和正在进行的其他地震活动的数据结合在一起，并将使用经过验证的建模技术进行分析，以生成TAMS和WSB下面的地震结构的详细图像。这些资料将被用来检验三个基本假设：TAMS被增厚的地壳覆盖，WSB具有地壳薄和沉积层厚的特点，TAMS下的走向普遍存在缓慢的地震速度。拟议研究的结果将提供有关南极大陆性质和形成的新信息，并将有助于增进我们对诸如造山和盆地形成等重要全球过程的了解。这项拟议的研究对南极科学的其他领域也有重要影响。对于气候和冰盖模型来说，对TAMS隆起的起源的限制是至关重要的，而关于TAMS和WSB之下的热和岩石圈结构变化的新信息将被用来估计关键的冰盖边界条件。更广泛的影响：该项目包括三项教育战略，以促进教学和研究的一体化。研究生将通过实地考察和数据分析技术接受南极构造和地震处理方面的培训。通过NSF的PolarTREC计划，PI将与K-12教育工作者合作。PI将为阿拉巴马州少数族裔服务机构的应届高中毕业生和职业生涯早期的本科生开发一个为期三周的暑期实地考察项目。教学材料和参与者的经验将通过课程网站与计划外的个人分享。暑期项目结束后，特别投入的参与者将获得分析TAMNNET数据的实习机会。在接下来的几年里，这些学生可以帮助进行实地考察，并可以在PI的指导下被招募到研究生项目中。归根结底，这个项目不仅能帮助培养本科生，还能培养出一批未被充分代表的学生进入地球科学领域。

Intellectual Merit: To understand Antarctica's geodynamic development, origin of the Transantarctic Mountains (TAMs) and the Wilkes Subglacial Basin (WSB) must be determined. Current constraints on the crustal thickness and seismic velocity structure beneath the TAMs and the WSB are limited, leading to uncertainties over competing geologic models that have been suggested to explain their formation. The PI proposes to broaden the investigation of this region with a new seismic deployment, the Transantarctic Mountains Northern Network (TAMNNET), a 15-station array across the northern TAMs and the WSB that will fill a major gap in seismic coverage. Data from TAMNNET will be combined with that from other previous and ongoing seismic initiatives and will be analyzed using proven modeling techniques to generate a detailed image of the seismic structure beneath the TAMs and the WSB. These data will be used to test three fundamental hypotheses: the TAMs are underlain by thickened crust, the WSB is characterized by thin crust and thick sedimentary layers, and slow seismic velocities are prevalent along strike beneath the TAMs. Results from the proposed study will provide new information about the nature and formation of the Antarctic continent and will help to advance our understanding of important global processes, such as mountain building and basin formation. The proposed research also has important implications for other fields of Antarctic science. Constraints on the origin of the TAMs uplift are critical for climate and ice sheet models, and new information acquired about variations in the thermal and lithospheric structure beneath the TAMs and the WSB will be used to estimate critical ice sheet boundary conditions. Broader impacts: This project incorporates three educational strategies to promote the integration of teaching and research. Graduate students will be trained in Antarctic tectonics and seismic processing through hands-on fieldwork and data analysis techniques. Through NSF's PolarTREC program, the PI will work with K-12 educators. The PI will develop a three-week summer field program for recent high school graduates and early-career undergraduate students from Minority-Serving Institutions in Alabama. Teaching materials and participant experiences will be shared with individuals outside the program via a course website. Following the summer program, participants who were particularly engaged will be offered internship opportunities to analyze TAMNNET data. In successive years, the students could assist with fieldwork and could be recruited into the graduate program under the PI's supervision. Ultimately, this program would not only serve to educate undergraduates but would also generate a pipeline of underrepresented students into the geosciences.