Collaborative Research: Development of an Ultra High Resolution Scanning SQUID Microscope for Paleomagnetic and Rock Magnetic Studies

该奖项支持加州理工学院（EAR-0004069）和范德比尔特大学之间的合作研究项目，开发用于古地磁和岩石研究的超高分辨率扫描超导量子干涉装置（SQUID）显微镜（UHRSSM）。该仪器将基于一个小型超导拾取线圈，连接到一个SQUID传感器，该传感器安装在一个回旋器的真空空间中，悬浮在一个比室温样品高不到50毫米的蓝宝石薄窗后面。扫描样品使我们能够以小至100mm的空间分辨率绘制样品上方磁场的z分量（主要受拾取线圈直径的限制）。与商用SQUID力矩磁力计相比，样品和拾取线圈之间的紧密间距使灵敏度提高了四个数量级。新的仪器将允许进行新的古地磁分析：(1)在极小的空间尺度上进行砾岩、烤接触和褶皱试验，极大地扩展了这些关键的地质场磁稳定性试验的实用性；(2)在标准岩石薄片上进行一套岩石磁性和古地磁实验，使观察到的磁性成分与存在的矿物相匹配；(3)对单个矿物颗粒进行非常高速率的泰勒-泰勒古强度分析；(4)高分辨率磁地层学；(5)亚毫米尺度薄片上岩石磁资料与SEM、微探针等资料的空间对比研究

0004069KirschvinkThis award supports a collaborative research Project between Caltech (EAR-0004069) and Vanderbilt University to develop an Ultra High Resolution Scanning Superconducting Quantum Interference Device (SQUID) Microscope (UHRSSM) for Paleomagnetic and Rock Studies. The instrument will be based on a small superconducting pickup coil coupled to a SQUID sensor housed in the vacuum space of a cyrostat, suspended behind a thin sapphire window less than 50mm above a room temperature sample. Scanning the sample allows us to map the z-component of the magnetic field above the sample with spatial resolutions as small as 100mm (limited mainly by the pickup coil diameter). The close spacing between sample and pickup coil results in an increase in sensitivity by four orders of magnitude compared to commercial SQUID moment magnetometers. The new instruments will allow for new classes of paleomagnetic analyses: (1) Conglomerate, baked contact, and fold tests on extremely small spatial scales, vastly expanding the utility of of these critical geological field tests of magnetic stability, (2) a suite of rock-magnetic and paleomagnetic experiments on standard petrographic thin sections, allowing the observed magnetic components to be matched with the minerals that are present, (3) Thellier-Thellier paleointensity analyses on individual mineral grains and at very high rates, (4) high resolution magnetic stratigraphy, and (5) spatial correlation of rock magnetic data with SEM, microprobe and other data on thin sections, at submillimeter scales.***