Multimethod chronology was applied on intrusives bordering the Kyrgyz South Tien Shan suture (STSs) to decipher the timing of (1) formation and amalgamation of the suturing units and (2) intracontinental deformation that built the bordering mountain ranges. Zircon U/Pb data indicate similarities between the Tien Shan and Tarim Precambrian crust. Caledonian (∼440–410 Ma) and Hercynian (∼310–280 Ma) zircon U/Pb ages were found at the edge of the STSs, related to subduction and closure of the Turkestan Ocean and the formation of the suture itself. Permian‐Triassic (∼280–210 Ma) titanite fission track and zircon (U‐Th)/He data record the first signs of exhumation when the STSs evolved into a shear zone and the adjacent Tarim basin started to subside. Low‐temperature thermochronological (apatite fission track, zircon and apatite (U‐Th)/He) analyses reveal three distinct cooling phases, becoming younger toward the STSs center: (1) Jurassic‐Cretaceous cooling ages provide evidence that a Mesozoic South Tien Shan orogen formed as a response to the Cimmerian orogeny; (2) Early Paleogene (∼60–45 Ma) data indicate a renewed pulse of STSs reactivation during the Early Cenozoic; (3) Neogene ages constrain the onset of the modern Tien Shan mountain building to the Late Oligocene (∼30–25 Ma), which intensified during the Miocene (∼10–8 Ma) and Pliocene (∼3–2 Ma). The Cenozoic signals may reflect renewed responses to collisions at the southern Eurasian border (i.e., the Kohistan‐Dras and India‐Eurasia collisions). This progressive rejuvenation of the STSs demonstrates that deformation has not migrated steadily into the forelands, but was focused on pre‐existing basement structures.

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Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been established as a powerful surface analytical method for local elemental analysis on metallic, ceramic, geological or biological sample surfaces. Here we show a new way of nanometre scale analysis of elements on sample surfaces by near-field LA-ICP-MS (NF-LA-ICP-MS). This technique uses the near-field enhancement effect on the tip of a thin silver needle in a laser beam (Nd:YAG laser, wavelength 532 nm) on the sample surface. The thin silver needle was etched electrolytically in an electrochemical cell using a droplet of citric acid as electrolyte. For nanolocal analysis by NF-LA-ICP-MS on soft matter (e.g., on 2-D gels and biological samples) a small volume transparent laser ablation chamber was constructed and coupled to a double-focusing sector field inductively coupled plasma mass spectrometer (ICP-MS). A small amount of soft sample material is ablated at atmospheric pressure by a single laser shot in the near-field of the silver tip in the defocused Nd:YAG laser beam. The ablated material is transported with argon as carrier gas into the inductively coupled plasma (ICP) ion source of the sensitive double-focusing sector field mass spectrometer with reverse Nier-Johnson geometry. By single-shot analysis on 2-D gels and biological surfaces doped with uranium in the mg g À1 range using NF-LA-ICP-MS an enhancement of ion intensities of transient signals in comparison with the background signal of up to factor 60 was observed. In gels doped with isotopically enriched 65 Cu and 67 Zn spikes by NF-LA-ICP-MS (single shot analysis) ion intensities up to the n  10 5 cps range and isotope ratios (235 U/ 238 U, 65 Cu/ 63 Cu and 67 Zn/ 64 Zn) were measured at a lateral resolution in the nanometre scale. Using the near-field effect in LA-ICP-MS, it was demonstrated that nanolocal analysis is possible in single-shot measurements of elements on biological samples and on a gel surface with spatial resolution at the hundreds of nanometres range. This first experiment on near-field LA-ICP-MS opens up a new, challenging path for future applications in nanoimaging of elements in life science, biology and medicine, e.g., for analyses of single cells, cell organelles or biological structures at nanometre range in order to detect neurodegenerative diseases, but also in material science, nanotechnologies and nanoelectronics.

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The determination of 129 I in environmental samples at ultratrace levels is very difficult by ICP-MS due to a high noise caused by Xe impurities in argon plasma gas (interference of 129 Xe 1), possible 127 IH 2 1 interference and an insufficient abundance ratio sensitivity of the ICP mass spectrometer for 129 I/ 127 I isotope ratio measurement. A sensitive, powerful and fast analytical technique for iodine isotope ratio measurements in aqueous solutions and contaminated soil samples directly without sample preparation using ICP-MS with a hexapole collision cell (ICP-CC-QMS) was developed. Oxygen is used as reaction and carrier gas for iodine thermal desorption via the gas phase from solid environmental material in the sample introduction device coupled on-line to ICP-CC-QMS. A mixture of oxygen and helium as reaction gases in the hexapole collision cell was applied for reducing disturbing background intensity of 129 Xe 1. After optimization of measurement procedures the detection limit for 129 I 1 in aqueous solution was 8 6 10 213 g ml 21 , which is better by about two orders of magnitude in comparison to the detection limit for 129 I 1 in sector field ICP-MS. The detection limit for direct 129 I 1 determination in contaminated environmental (soil) samples via gas-phase desorption without any additional sample preparation was 3 6 10 211 g g 21 (30 ppt). Furthermore, the results of the determination of 129 I/ 127 I isotope ratios at the 10 25-10 26 level in synthetic laboratory standards and environmental soil samples from contaminated areas are given.