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The Sensitive High Resolution Ion Micro Probe (SHRIMP) IIe is a high precision Secondary Ion Mass Spectrometer (SIMS).Ion microprobes make in situ isotopic and chemical 'surface' analysis of solid targets by bombarding the sample with an ion beam with a diameter of several microns typically employing Kohler focussing.The mount has to be polished and coated with conductive material (eg gold or aluminium) to prevent charge build up. A focussed primary beam of oxygen or caesium ions are focussed to a 10-30 micron (0.01-0.03 mm) spot on the sample.This sputters material from the surface of the sample, some of which is ionised.The oldest zircon on Earth was measured in the SHRIMP Facility.

Ions of different energy will therefore travel different paths.Research into ore localisation, ore sources, and ore remobilisation by UWA Centre for Exploration Targeting academics, as well as ore deposit exploration by Australian and international mining companies relies on the Curtin SHRIMP Facility.Accurate SHRIMP age data on intrusive dikes swarms, gigantic flood basalt provinces and granite intrusion is essential for plate tectonic models of super continent formation and subduction related fold belts.The high mass resolution of SHRIMP IIe is achieved by the use of double-focussing mass spectrometer (simultaneous energy and mass refocussing) with a very large turning radius of Magnet and Electrostatic Analyser.SHRIMP has many applications: zircon dating in copper-uranium-gold-silver deposits, uranium-lead dating of sulphur in the sulphide minerals that form metal ores, the isotopic composition of sulphur in the giant base metal ore bodies.Two samples of gneissic granodiorite (XG1-1) and gneissic quartz diorite (J48-1) have magmatic ages of 25 Ma, respectively.

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