Of course, this is balanced with gas content -- if the magma contains more gas bubbles, it will erupt more violently, and if it contains less gas, it will erupt more calmly.
A memorandum of understanding (MOU) is an agreement between two parties in the form of a legal document. It is not fully binding in the way that a contract is, but it is stronger and more formal than a traditional gentleman's agreement. Sometimes, the term is used as a synonym for a letter of intent, particularly in private law.
ECU. An electronic device that remotely controls home climate (e.g., heating, air conditioning), security (e.g., lighting, door locks, drapes), and communication devices (telephone, television). ECUs are often, but not exclusively, used by persons with functional limitations.