1 How Did We Get to This Point Visitors to the La Brea Tar Pits in Los Angeles CA can see a replica of a mammoth stuck in a tar pit 4
Oil collects underground Oil collects underground Millions of years ago tiny animals and plants lived in Earth’s oceans They died there too Their bodies sank into mud Over time sand and silt piled up on them Those heavy layers created heat and pressure which turned the remains into crude oil or petroleum Oil coal and natural gas all form from ancient creatures They are called fossil fuels Oil collects underground Some of it leaks up through cracks called seeps The oil is mixed with tar natural gas and water Long ago people dug up seeps to fi nd oil Native Americans used oil from seeps as paint They used tar to glue tools They waterproofed baskets and canoes Later settlers used oil in lamps to grease machinery and to pave roads Warm tar or asphalt is sticky Animals can be trapped in it The La Brea Tar Pits near Los Angeles CA is a famous seep Visitors can see fossils from extinct animals 5
Finding and Removing Oil Now geologists search for oil They study rocks and land features They check satellite images They use sound waves to map rock layers Before they drill oil companies study the impact on the environment Workers build roads clear trees and level the land Tall derricks on land or on oil platforms at sea hold up drilling machinery Underground drill bits on long pipes cut through rock Fluid pumped down through the pipes helps cool the machinery It carries rock bits back up A drill can reach down a mile or more to find oil Oil workers use sharp drill bits and many pipes to reach oil underground 6
Hydraulic fracturing or fracking reaches oil and gas in rock Hydraulic fracturing or fracking reaches oil trapped in rock Fluid is pumped in under high pressure The fluid can contain water chemicals and sand It dissolves channels in the rock Oil and gas flow out Geologists have not determined all the risks in fracking To reach oil underwater companies drill offshore Equipment rests on the seafloor floats on a barge or works from a ship or pontoon Companies make huge investments before they know whether a well will ever produce oil
