for a good example of a family taking the long term view, look at the Tom O'Connor ranch in Victoria,Refugio, and Goliad counties, Texas. There were two giant fields discovered in the 1930's on their property, Tom O'Connor and Greta. They discovered the Lake Pasture field themselves in the '50's. They have consistently not leased since then because their family has enough money, about a gazillion dollars.
  They have about 300,000 unexplored acres in the Frio, and Wilcox trends. The O'Connors are an extremely private family and very conservative in the good sense of being religeous and traditionalists not the NeoConartist sense. They have in my opinion the best unexplored acreage in the state, excepting the undrilled deep-seated salt dome under Memorial Park and River Oaks Country club in Houston.