Changes

|+ {{table number|1}}Energy sources

|+ {{table number|1}}Energy sources

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! Source

! Source || Application || Advantages || Disadvantages

! Application

! Advantages

! Disadvantages

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| Explosives

| Explosives || General acquisition || Short, broad band pulse. Source can be placed below weathering layer. || Requires expensive shothole drilling. Frequency dependent on material in which explosion occurs. Dangerous to handle.

| General acquisition

| Short, broad band pulse. Source can be placed below weathering layer.

| Requires expensive shothole drilling. Frequency dependent on material in which explosion occurs. Dangerous to handle.

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| Vibrators

| Vibrators || General acquisition || Minimal cultural and environmental impact. Controlled frequency source. Narrow frequency band can increase signal to noise ratio. No shot holes required. || Shallow weathering can cause statics problems. Base-plate to ground coupling can be a problem. More complex recording and processing.

| General acquisition

| Minimal cultural and environmental impact. Controlled frequency source. Narrow frequency band can increase signal to noise ratio. No shot holes required.

| Shallow weathering can cause statics problems. Base-plate to ground coupling can be a problem. More complex recording and processing.

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| Gas or air guns

| Gas or air guns || Acquisition in rough terrain || Cheap. Heli-portable. Can use multiple sources. No shot holes required. || Limited energy penetration. Ground roll problems. Requires longer offsets. Shallow weathering can cause statics problems.

| Acquisition in rough terrain

| Cheap. Heli-portable. Can use multiple sources. No shot holes required.

| Limited energy penetration. Ground roll problems. Requires longer offsets. Shallow weathering can cause statics problems.

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| Weight drop

| Weight drop || General acquisition. Desert acquisition. || Cheap. No shot holes required. || Cannot synchronize sources. Ground roll problems. Requires longer offsets. Shallow weathering can cause statics problems.

| General acquisition. Desert acquisition.

| Cheap. No shot holes required.

| Cannot synchronize sources. Ground roll problems. Requires longer offsets. Shallow weathering can cause statics problems.

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