Disclosed is a process for preparation of compositions having utility as well fluid base oils. The process involves metathesis of alpha-olefins followed by isomerization of the metathesis products. The base oils resulting from the process of this invention are environmentally friendly in that they are only mildly toxic to marine life and have very low pour point temperatures. These properties make the base oils ideal candidates for use as components of well fluids for cold climates and offshore applications.