Land streamer surveying using multiple sources

Abstract

Various examples are provided for land streamer seismic surveying using multiple sources. In one example, among others, a method includes disposing a land streamer in-line with first and second shot sources. The first shot source is at a first source location adjacent to a proximal end of the land streamer and the second shot source is at a second source location separated by a fixed length corresponding to a length of the land streamer. Shot gathers can be obtained when the shot sources are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first shot source. The second shot source is separated from the first shot source by a fixed overall length corresponding to the land streamer.

Therefore, at least the following is claimed: 
     
         1 . A method for seismic surveying, comprising:
 disposing a land streamer in-line with first and second shot sources, the first shot source at a first source location adjacent to a proximal end of the land streamer, the second shot source at a second source location separated from the first shot source by a fixed length corresponding to a length of the land streamer;   firing the first shot source at the first source location and obtaining a first shot gather from the land streamer; and   firing the second shot source at the second source location and obtaining a second shot gather from the land streamer.   
     
     
         2 . The method of  claim 1 , further comprising:
 repositioning the land streamer with the first and second shot sources, wherein the first shot source is approximately at the second source location and the second shot source is at a third source location separated from the first shot source by the fixed length, the land streamer in-line with first and second shot sources; and   firing the first shot source at approximately the second source location and obtaining a third shot gather from the land streamer.   
     
     
         3 . The method of  claim 2 , further comprising generating an extended shot gather based upon the third shot gather and the second shot gather. 
     
     
         4 . The method of  claim 2 , further comprising firing the second shot source at the third source location and obtaining a fourth shot gather from the land streamer. 
     
     
         5 . The method of  claim 2 , wherein the third source location is in-line with the first and second source locations. 
     
     
         6 . The system of  claim 2 , wherein the second shot source, the first shot source, and the land streamer are repositioned along a predefined survey route by a vehicle. 
     
     
         7 . The system of  claim 6 , wherein the displacement of the second shot source, the first shot source, and the land streamer by the vehicle is guided by a global positioning system (GPS). 
     
     
         8 . The method of  claim 2 , wherein the land streamer, the first shot source, and the second shot source are configured to maintain alignment and separation while being repositioned. 
     
     
         9 . The method of  claim 1 , further comprising firing a third shot source at a third source location in-line with the first and second shot sources, the third shot source separated from the second shot source by the fixed length, and obtaining a third shot gather from the land streamer. 
     
     
         10 . The method of  claim 9 , further comprising:
 repositioning the land streamer with first, second and third shot sources, wherein the first shot source is approximately at the second source location, the second shot source is approximately at the third source location, and the third shot source is at a fourth source location separated from the second shot source by the fixed length, the land streamer in-line with first, second and third shot sources; and   firing the second shot source at the third source location and obtaining a fourth shot gather from the land streamer.   
     
     
         11 . The method of  claim 10 , further comprising generating an extended shot gather based upon the third shot gather and the fourth shot gather. 
     
     
         12 . The method of  claim 10 , further comprising:
 repositioning the land streamer with first, second and third shot sources, wherein the first shot source is approximately at the third source location, the second shot source is approximately at the fourth source location, and the third shot source is at a fifth source location separated from the second shot source by the fixed length, the land streamer in-line with first, second and third shot sources; and   firing the first shot source at the third source location and obtaining a fifth shot gather from the land streamer, wherein the extended short gather is based upon the third, fourth and fifth shot gathers.   
     
     
         13 . The method of  claim 12 , further comprising generating an extended shot gather based upon the third shot gather, the fourth shot gather, and the fifth shot gather. 
     
     
         14 . The method of  claim 1 , wherein the land streamer includes a plurality of receivers spaced between the proximal end and a distal end of the land streamer, the first source adjacent to a proximal end receiver located at the proximal end of the land streamer and the second source on a side of the first shot source opposite the proximal end of the land streamer, where the fixed length is a length from the first shot source to a distal end receiver located at the distal end of the land streamer. 
     
     
         15 . The method of  claim 14 , wherein the first shot source and the second shot source are sequentially fired to obtain corresponding shot gathers using the plurality of receivers without displacement of the land streamer. 
     
     
         16 . The system of  claim 14 , wherein a seismic recording system records the first shot gather from the plurality of receivers in response to firing the first shot source and records the second shot gather from the plurality of receivers in response to firing the second shot source. 
     
     
         17 . The system of  claim 16 , wherein the seismic recording system is communicatively coupled to the plurality of receivers through a plurality of channels. 
     
     
         18 . The method of  14 , further comprising firing a third shot source at a third source location and obtaining a third shot gather from the land streamer, wherein the third shot source is disposed in-line with the land streamer, the first shot source and second shot source and located on a side of the second shot source opposite the first shot source, the third shot source separated from the second shot source by the fixed length. 
     
     
         19 . The method of  claim 18 , further comprising generating an extended shot gather by concatenating the first shot gather, the second shot gather and the third shot gather together. 
     
     
         20 . The system of  claim 14 , wherein the plurality of receivers are secured together at even intervals between the proximal end and the distal end of the land streamer.