Controlled source electromagnetic method of detecting oil and gas reservoir

The invention discloses a controlled source electromagnetic method of detecting an oil and gas reservoir, and belongs to the geophysical exploration technology field. A novel land controllable source electromagnetic method adopts a ground long lead as an emission source, and is used to observe a horizontal electric field in an area, and an included angle between the emission source and the area is in a range from 30degrees to 40degrees. The controlled source electromagnetic method comprises steps that the ground long lead is used as the emission source, and the horizontal electric field is observed in the area, and the included angle between the emission source and the area is in the range from 30degrees to 40degrees, and then one-dimensional inversion of observation data is carried out. The controlled source electromagnetic method is advantageous in that electromagnetic waves having dominant direct waves are acquired, and influences of air waves are effectively reduced, and then maximum sensitivity observation of a high-resistance target body is realized, and in addition, the detection effect of the deep oil and gas reservoir is obviously improved.