Oil painting North, starting in Venice in the late 15th century. By 1540, the previous method for painting on panel (tempera) had become all but extinct, although Italians continued to use chalk-based fresco for wall paintings, which was less successful and durable in damper northern climates. The linseed oil itself comes from the flax seed, a common fiber crop. Linen, a "support" for oil painting (see relevant section), also comes from the flax plant. Safflower oil or the walnut or poppyseed oil are sometimes used in formulating lighter colors like white because they "yellow" less on drying than linseed oil, but they
Oil platform onshore. Subsea facilities are also easier to expand, with new separators or different modules for different oil types, and are not limited by the fixed floor space of an above-water installation. Offshore oil production involves environmental risks, most notably oil spills from oil tankers or pipelines transporting oil from the platform to onshore facilities, and from leaks and accidents on the platform. Produced water is also generated, which is water brought to the surface along with the oil and gas; it is usually highly saline and may include dissolved or unseparated hydrocarbons. The world's deepest oil platform is the floating