Roger Jay Steffensen was born September 23, 1940, in Oklahoma City and was adopted shortly after by John and Irene Steffensen of Chelsea. Roger played clarinet at Chelsea High School and graduated as valedictorian of the CHS Class of 1958. He graduated from Oklahoma State University in 1962 with a BS in Mechanical Engineering. He then attended Purdue University, where he received his MS in Mechanical Engineering in 1964 and his PhD in Mechanical Engineering in 1966. Roger worked the majority of his career as a Petroleum Engineer at Amoco Production Company at the 41st and Yale Research Center in Tulsa. As a long-time member of the Society of Petroleum Engineers, he wrote the chapter on "Solution-Gas-Drive Reservoirs" for the SPEs "Petroleum Engineering Handbook" in 1987 and published at least eight articles in various professional journals. He was awarded US Patent 3795142 and Canadian Patent 958324 in 1974 for "Temperature Well Logging", a method for determining the depth(s) of permeable rock layers in an oil-well bore. Roger retired from Amoco as a Senior Petroleum Engineering Associate in 1997 and later worked as a Distinguished Engineering Advisor for PetroTel, Inc. of Plano, TX, until 2008. Roger married Janice M Post on October 23, 1976. He had two sons from a prior marriage and was a proud grandfather of three. Roger was most recently a member of Asbury United Methodist Church and moved to Oklahoma Methodist Manor in 2009. Roger passed on April 19, 2012, at the age of 71, from complications of Alzheimers type dementia. Roger is survived by his wife, Jan; his sons, Kirk and Michael; Kirks wife, Leslie; his grandchildren, Gregory (18), Henry (16) and Charlotte (14); and Jans brothers, Frank and Robert. Service: 04/03/2012 11:00 AM Asbury United Methodist Church Mason Chapel 6767 S. Mingo Road Tulsa, OK 74133