Facility Support: Pinon Flat Observatory - Longbase Strainmeters Interim Operation

设施支持：Pinon Flat 天文台 - 长基应变计临时运行

• 批准号: 1533790
• 负责人: Duncan Carr Agnew
• 金额: $ 22.75万
• 依托单位: University of California-San Diego Scripps Inst of Oceanography
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1533790&HistoricalAwards=false
• 关键词: Facility; Support; Pinon; Flat; Observatory

1533790AgnewThis grant support continuity of operations and maintenance of the Pinon Flat Observatory (PFO) long-baseline laser strainmeters (3) and one long baseline tiltmeter for a period of forty months (congruent with the expiration of the GAGE Facility Cooperative Agreement EAR-1261833). PFO is the only location in which three LSM?s allow the full strain tensor to be measured with a long-term stability that matches GPS, with a short-term sensitivity orders of magnitude better than GPS, and without the calibration concerns and hydrologic effects present on borehole strainmeters. The unmatched "temporal depth" of the PFO data (including a number of environmental sensors) makes it possible to evaluate a range of new signals and to identify patterns which appear only over very long times. PFO LSMs have detected repeated aseismic signals triggered by local earthquakes, observed seven times over the last 22 years, and thought to be caused by aseismic slip within the Anza gap of the nearby San Jacinto Fault. The LSM data extend back to the early 1970?s, and in improved form (fully-anchored) back to the mid-1980?s. The PFO LSM time series observations are unique in the world and are in a strategic area of the transform fault system that runs throughout southern and into northern California and that remains a serious and potent seismic hazard for a large population base in the U.S. The extreme sensitivity of in vacuo laser interferometric crustal displacement gradient measurements such as at PFO offers the real possibility of witnessing seismic precursors within the Anza seismic gap. The Anza gap is seismically quiet compared to regions of the transform fault system to the south and the north. This area is certainly potentially ripe for a major earthquake though it may be an area of the transform that accommodates strain accumulation largely through aseismic slip. However, if a major earthquake in the region should occur, the loss of the important long time series PFO LSM data sets would be less than unfortunate given the marginal costs of keeping it running until other sources of support might be found post-September 2018. This support is congruent with NSFs mission of promoting the progress of science and may well advance the national health, prosperity and welfare in terms of advancing knowledge about seismic hazards and hazard mitigation.***

1533790Agnew 这项拨款支持皮农平地天文台 (PFO) 长基线激光应变仪 (3) 和一台长基线倾斜仪四十个月的连续运行和维护（与 GAGE 设施合作协议 EAR-1261833 的到期一致）。 PFO 是唯一一个三个 LSM 允许测量完整应变张量的位置，其长期稳定性与 GPS 相匹配，短期灵敏度比 GPS 好几个数量级，并且没有钻孔应变计上存在的校准问题和水文影响。 PFO 数据（包括许多环境传感器）无与伦比的“时间深度”使得评估一系列新信号并识别仅在很长一段时间内出现的模式成为可能。 PFO LSM 已检测到由当地地震引发的重复地震信号，在过去 22 年中观测到了七次，并被认为是由附近圣哈辛托断层安扎间隙内的地震滑移引起的。 LSM 数据可追溯到 1970 年代初期，并以改进的形式（完全锚定）追溯到 1980 年代中期。 PFO LSM 时间序列观测在世界上是独一无二的，并且位于贯穿加利福尼亚州南部和北部的转换断层系统的战略区域，对于美国的大量人口基数来说，该断层系统仍然是一个严重而有力的地震危险。真空激光干涉地壳位移梯度测量（例如 PFO）的极端灵敏度提供了在 Anza 地震中见证地震前兆的真正可能性。 差距。 与南部和北部转换断层系统的区域相比，安扎间隙的地震较为安静。 尽管该地区可能是一个主要通过地震滑移来容纳应变积累的转变区域，但它确实有可能发生大地震。 然而，如果该地区发生大地震，考虑到在 2018 年 9 月后找到其他支持来源之前保持其运行的边际成本，重要的长期序列 PFO LSM 数据集的丢失也不算不幸。这种支持与 NSF 促进科学进步的使命相一致，并且在提高有关地震灾害和危害的知识方面可能会很好地促进国民健康、繁荣和福利 缓解措施.***