Investigation into magma degassing at Nyiragongo volcano, Democratic Republic of the Congo

摘要: [1] We report the first combined measurements of composition and flux gas emitted from Nyiragongo volcano by ground-based remote-sensing techniques. Ultraviolet spectroscopic made in May/June 2005 January 2006 indicate average SO(2) emission rates 38 kg s(-1) 23 s(-1), respectively. Open-path Fourier transform infrared obtained 2005, 2006, June 2007 molar proportions 70, 24, 4.6, 0.87, 0.26, 0.11, 0.0016% for H(2)O, CO(2), SO(2), CO, HCl, HF, OCS, The plume was remarkably similar 2007, with little temporal variation particular, on scale seconds or days even between three field campaigns that span a period 24 months. This stability persisted despite wide range degassing behaviors surface summit crater's lava lake ( including discrete strombolian bursts fountains) variations rate. explain these observations regime steady state which bubbles nucleate ascend chemical equilibrium convecting magma. Short-term to minutes) fluctuations SO(2)-HCl-HF were observed, are attributed shallow processes.