Acquisition of a DC-SQUID magnetometer

这项拨款支持购买超导量子干涉装置（SQUID）岩石磁力计（SRM），该磁力计配置用于测量离散样品和连续沉积物岩心或u形通道的剩余磁化。SQUID SRM将取代1986年安装在明尼苏达大学的现有基于射频（RF）探测的SRM，并且可以检测到比RF-SRM低三个数量级的剩磁，从而可以表征弱磁化的沉积物和岩石。目前，明尼苏达大学由美国国家科学基金会支持的岩石磁性研究所（IRM）国家多用户设施（EAR- 0218384）安置了大量专门的岩石磁性设备。这种u通道的SQUID SRM将成为测量室温和零场下剩磁的基本IRM工具。此次收购将促进岩石磁学、环境和古磁学的基础研究。具体的内部岩石磁性研究包括：1)精确表征颗粒间静磁相互作用及其对各种剩余磁化性质的各向异性影响，以支持岩石组构的研究；2)详细研究天然沉积物的磁矫顽力谱，从沉积和土壤记录中提取磁矿物学和粒度信息；3)对含游离磁性氧化物包裹体的单晶硅酸盐矿物标本的自然残余物进行灵敏检测，解析磁性载体相的来源。u型通道能够连续测量沉积物岩心中的磁性残余，这也将促进古地磁、磁地层学和环境磁学的研究。这些研究对于认识地磁场动力学和揭示沉积古环境条件具有重要意义。u通道SQUID SRM将通过IRM设施免费提供给更广泛的地球科学社区。IRM每年支持大量美国和国际科学家进行岩石地磁和古地磁研究。学生和博士后学者可以通过访问学者计划通过IRM主办的旅行支持访问该仪器。pi计划开发和分发一套特性良好的标准材料，所有获得的磁性数据将通过可访问的网络岩石磁性数据库免费提供。* * *

0647852BanerjeeThis grant supports acquisition of a superconducting quantum interference device (SQUID) rock magnetometer (SRM) configured to measure the remanent magnetization of both discrete specimens and continuous sediment cores or u-channels. The SQUID SRM would replace an existing radio frequency (RF) detection based SRM installed at the University of Minnesota in 1986 and would allow for detection of magnetic remanence up to three orders of magnitude lower than currently possible with the RF-SRM, allowing for characterization weakly magnetized sediments and rocks. Currently a wide range of specialized rock magnetic equipment is housed at the NSF supported Institute for Rock Magnetism (IRM) national multi-user facility (EAR- 0218384) at the University of Minnesota. This u-channel capable SQUID SRM will be a fundamental IRM tool used for the measurement of magnetic remanence at room-temperature and zero-field. Fundamental research in rock magnetism, environmental and paleomagnetism will be facilitated by this acquisition. Examples of specific in-house rock magnetic research includes: 1) precise characterization of interparticle magnetostatic interactions and their anisotropic effects on the properties of various remanent magnetizations to support study of rock fabrics; 2) detailed studies of the magnetic coercivity spectra of natural sediments to extract information on magnetic mineralogy and grain size from sedimentary and soil records; and 3) sensitive detection of the natural remanence of single-crystal silicate mineral specimens containing exsolved magnetic oxide inclusions to resolve the origin of magentic carrier phases. Studies in paleomagnetism, magnetostratigraphy and environmental magnetism will also be facilitated by the u-channel capability for continuous measurement of magnetic remanence in sediment cores. Such studies are important to understand the dynamics of the geomagnetic field and to unravel depositional paleoenvironmental conditions. The u-channel SQUID SRM will be freely available to the broader geoscience community through the IRM facility. The IRM supports rock magnetic and paleomagnetic research by a large number of U.S. and international scientists annually. Students and postdoctoral scholars may gain access to the instrument via IRM hosted travel support through their Visiting Fellows program. The PIs plan to develop and distribute a set of well-characterized standard materials and all magnetic data acquired will be made freely available through web-accessible rock magnetic databases. ***