Alaska Dispatch by Alex DeMarban (NGP Photo).  This is the third installment of a three-part series regarding Shell's upcoming offshore activity in Alaska's Arctic region. Part 1: Shell readies to roll dice on multibillion-dollar bet in Arctic. Part 2: Will offshore oil development in Alaska's Arctic make state rich? Don't count on it.   A chunk of ice the size of a small stadium, perhaps a rogue remnant of a distant ice island, recently ground ashore near the Northwest Alaska village of Wainwright, providing a textbook example for the kind of subsea phenomena [...]