1 No early symptoms. 2  Blood in the urine - often intermittently. 3  Kidney area lump. 4  Abdominal swelling.  No pain - there is not usually any kidney pain unless the tumor is very advanced.
Gas content varies depending on what sort of material melted to form the magma. As a general rule, the most explosive eruptions come from magmas that have high gas levels and high viscosity, while the most subdued eruptions come from magmas with low gas levels and low viscosity.
Volcanic eruptions, like many geophysical phenomena, span a vast range of scales of size, rate, and duration. The mass of magma ejected during an eruption, the quantities of gas released, and the eruptive flux all vary by many orders of magnitude.