native asphalt

native asphalt

[′nād·iv ′as‚fȯlt] (geology) Exudations or seepages of asphalt occurring in nature in a liquid or semiliquid state. Also known as natural asphalt.

natural asphalt

Asphalt occurring in nature, produced from petroleum by natural evaporation or distillation; usually not suitable for paving purposes until refined and softened to proper consistency by combining with flux oil.