Drilling, perforating and formation analysis

• US 20060102343A1
• Filed: 11/12/2004
• Published: 05/18/2006
• Est. Priority Date: 11/12/2004
• Status: Active Grant

• Current Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Original Assignee: Halliburton Energy Services Incorporated (Halliburton Company)
• Inventors: Pelletier, Michael T., Gleitman, Daniel D., Jones, Christopher M., Smith, Harry D. Jr., Skinner, Neal G.
• Granted Patent: US 7,490,664 B2
• Time in Patent Office: Days
• US Class Current: 166/250.100
• CPC Class Codes: B23K 26/082 Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head
• CPC Class Codes: E21B 36/04 using electrical heaters
• CPC Class Codes: E21B 43/11 Perforators; Permeators
• CPC Class Codes: E21B 49/00 Testing the nature of borehole walls; Formation testing; Methods or apparatus for obtaining samples of soil or well fluids, specially adapted to earth drilling or wells
• CPC Class Codes: E21B 49/06 using side-wall drilling tools pressing or scrapers
• CPC Class Codes: E21B 49/10 using side-wall fluid samplers or testers
• CPC Class Codes: E21B 7/15 of electrically generated heat
• CPC Class Codes: G01N 21/718 Laser microanalysis, i.e. with formation of sample plasma
• CPC Class Codes: G01N 21/954 Inspecting the inner surface of hollow bodies, e.g. bores

Abstract

A system and method of drilling and/or perforating uses a laser beam to remove material, such as to perforate the casing, cement and formation or drill a well bore. The system and method can further or alternately encompass material analysis that can be performed without removing the material from the well bore. The analysis can be performed apart from or in connection with drilling operations and/or perforating the casing, cement and formation. The analysis can be used in a feed back loop to adjust material removal, adjust material analysis, determine the location of future material removal, and for other uses.

Claims

1. A device comprising:

a laser beam device adapted to output a laser beam; and

a laser beam directing device adapted to direct the laser beam to at least one of remove material or heat material to emit light at two or more locations about a well bore in an earth formation substantially concurrently.

2. The device of claim 1 wherein the laser beam directing device is adapted to direct the laser beam to at least one of remove material or heat material to emit light at a first of the at least two locations in a first duty cycle that is less than one;

and

wherein the laser beam directing device is adapted to direct the laser to a second of the at least two locations during an off cycle of the first duty cycle.

3. The device of claim 1 wherein the laser beam device is adapted to output the laser beam in a plurality of pulses.

4. The device of claim 1 wherein the laser beam directing device is adapted to be inserted into the well bore and to direct the laser beam onto a wall of the well bore.

5. The device of claim 1 wherein the laser beam device is adapted output a laser beam adapted to remove material of the earth formation;

and

wherein the device of claim 1 further comprises a focusing array adapted to adjust a focal length of the laser beam longer as a depth of a hole being formed by removing material increases.

6. The device of claim 1 wherein the laser beam directing device comprises a reflector.

7. The device of claim 1 further comprising an extendable light path extendable into a hole being formed and adapted to transmit the laser beam from the laser beam directing device into the hole.

8. The device of claim 1 further comprising an extendable light path extendable outward from the device and adapted to transmit at least one of the laser beam or light emitted from the heated material.

9. The device of claim 8 wherein the extendable light path comprises an optical fiber.

10. The device of claim 8 further comprising at least one of a pressure sensor or a temperature sensor on the extendable light path.

11. The device of claim 10 further comprising a processor operable in determining at least one of specific heat, thermal conductivity, or thermal diffusivity.

12. The device of claim 10 adapted to multiplex at least one of the laser beam or light emitted from the earth formation with a signal from the sensor.

13. The device of claim 1 further comprising an emitted light analyzing device adapted to determine at least one chemical characteristic of the material being heated.

14. The device of claim 13 wherein at least a portion of the emitted light analyzing device is adapted for insertion into a well bore.

15. The device of claim 13 wherein the emitted light analyzing device is adapted to perform laser induced breakdown spectroscopy.

16. The device of claim 1 further comprising a fluid outlet adapted to direct a fluid to at least partially overlap with the laser beam.

17. The device of claim 16 wherein the fluid outlet is adapted to direct the fluid to transmit at least one of the laser beam or the light emitted from the earth formation at least partially between the earth formation and the device.

18. The device of claim 1 wherein the laser beam directing device is adapted to be inserted into a well bore and further comprising a fluid outlet adapted to direct a fluid to impinge on a surface of the well bore.

19. The device of claim 18 wherein the fluid outlet is adapted to direct the fluid to at least one of at least partially clean a filter cake from the surface of the well bore or at least partially displace debris generated during the material removal.

20. The device of claim 1 wherein the laser beam directing device is adapted to direct the laser beam to at least one of perforate a wall of the well bore or drill the well bore.

21. The device of claim 1 wherein the laser beam is adapted to heat the earth formation to emit light by generating a first laser beam adapted to vaporize a material about the earth formation to form a cavity and generating a second laser beam adapted to heat at least a portion of the earth formation coinciding with the cavity to emit light.

181. The apparatus of claim 1 wherein the laser beam directing device comprises a plurality of optical fibers oriented to direct the laser beam in two or more trajectories.

190. The apparatus of claim 181 wherein the laser beam device is operable to adjust at least one of an energy, a power, a frequency, a duty cycle, a trajectory, and a focal point of the laser beam.

22. A method comprising:

directing a laser beam at a first location in a well bore in an earth formation in a plurality of first time intervals, the laser beam being adapted to at least one of remove material during the first time intervals or heat material to emit light during the first time intervals; and

directing the laser beam at a second location in at least one second time interval intervening the first time intervals.

23. The method of claim 22 wherein directing a laser beam at a first location in a plurality of first time intervals comprises operating the laser beam continuously and directing the laser beam away from the first location at times other than the first time intervals.

24. The method of claim 22 wherein directing a laser beam at a first location in a plurality of first time intervals comprises cycling the laser beam on to begin the first time interval and off to end the first time interval.

25. The method of claim 22 wherein the plurality of first time intervals comprises at least one of substantially equal time periods or unequal time periods.

26. The method of claim 22 wherein directing the laser beam at a second location in at least one second time interval comprises directing the laser beam at the second location during a second time interval of substantially equal duration as the first time interval.

27. The method of claim 22 further comprising generating the laser beam at least one of in a well bore or outside of a well bore.

28. The method of claim 22 wherein directing a laser beam at a first location comprises reflecting the laser beam off a reflector in a first trajectory and directing the laser beam at the second location of the earth formation comprises reflecting the laser beam off the reflector in a second trajectory.

29. The method of claim 22 further comprising determining at least one chemical characteristic of the material being heated about at least one of the first or the second location using laser induced breakdown spectroscopy.

30. The method of claim 29 further comprising removing material at the first location with the laser beam;

and

wherein determining at least one chemical characteristic material is at least partially performed substantially concurrently with removing material of the formation at the first location with the laser beam.

31. The method of claim 22 further comprising:

heating the earth formation at the first location to emit a first emitted light;

receiving the first emitted light; and

determining at least chemical characteristic of the earth formation from the first emitted light.

32. The method of claim 31 further comprising:

heating the earth formation at the second location to emit a second emitted light;

receiving the second emitted light; and

determining at least one chemical characteristic of the earth formation from the second emitted light.

33. The method of claim 22 further comprising directing a fluid to at least partially overlap with the laser beam.

34. The method of claim 33 wherein directing a fluid comprises directing the fluid substantially coaxially with the laser beam.

35. The method of claim 33 wherein the fluid is adapted to transmit at least one of the laser beam or the light emitted from the earth formation at least partially between a wall of the well bore and a location the emitted light is received.

36. The method of claim 22 further comprising directing a fluid to impinge on a surface of a well bore defined by the earth formation.

37. The method of claim 36 wherein the fluid outlet is adapted to direct the fluid to at least one of at least partially clean a filter cake from the surface of the well bore or at least partially displace debris generated during the material removal.

38. The method of claim 22 wherein directing the laser beam at a first location in a plurality of first time intervals comprises directing the laser beam to vaporize a material about the earth formation to form a cavity and directing the laser beam to heat at least a portion of the earth formation coinciding with the cavity to emit light.

182. The method of claim 22 wherein directing the laser beam at a first location comprises directing the laser beam through a first optical fiber oriented to direct the laser beam at the first location and directing the laser beam at the second location comprises directing the laser beam through a second optical fiber oriented to direct the laser beam at the second location.

39. An apparatus comprising:

a laser beam device adapted to direct a laser beam into at least one of a sidewall or a end wall of a wellbore in an earth formation, the laser beam adapted to heat material to emit light; and

a spectroscopy device adapted to receive the light emitted and to determine at least one chemical characteristic of the material from the emitted light.

40. The apparatus of claim 39 wherein at least a portion of the spectroscopy device is adapted to be positioned in the well bore.

41. The apparatus of claim 39 wherein at least a portion of the laser beam device is adapted to be positioned in the well bore.

42. The apparatus of claim 39 further comprising a focusing array adapted to focus the laser beam on the material being heated.

43. The apparatus of claim 42 wherein the laser beam is adapted to remove material;

and

wherein the focusing array is adapted to adjust a focal length of the laser beam longer as a depth of the material removed increases.

44. The apparatus of claim 39 wherein the laser beam is adapted to remove material.

45. The apparatus of claim 39 further comprising a reflector movable to direct the laser beam in at least two different trajectories.

46. The apparatus of claim 45 wherein the reflector is dichroic and adapted to reflect at least one wavelength of the laser beam and pass at least one other wavelength;

and

wherein the spectroscopy device is adapted to receive emitted light that passes through the reflector.

47. The apparatus of claim 39 wherein at least a portion of the laser beam device is encased in a housing, the housing having at least one window adapted to allow passage of the laser beam.

48. The apparatus of claim 39 further comprising an extendable light path adapted to extend outward from the apparatus into the well bore and to transmit at least a portion of the laser beam.

49. The apparatus of claim 48 wherein the extendable light path is extendable into a hole being formed in the well bore.

50. The apparatus of claim 48 wherein the extendable light path is adapted to transmit at least a portion of the light emitted.

51. The apparatus of claim 48 wherein the light path comprises at least one fiber optic.

52. The apparatus of claim 48 further comprising at least one sensor on the extendable light path.

53. The apparatus of claim 52 wherein the extendable light path is operable to transmit a signal from the sensor substantially concurrently with at least one of the laser beam or light emitted.

54. The apparatus of claim 39 further comprising at least one sensor extendable outward from the apparatus into the well bore.

55. The apparatus of claim 54 further comprising a processor operable in determining at least one of specific heat, thermal conductivity, or thermal diffusivity.

56. The apparatus of claim 39 wherein the laser beam device is adapted to at least one of generate the laser beam within the well bore or relay a laser beam generated remote from the laser beam device.

57. The apparatus of claim 39 wherein the laser beam device and spectroscopy device operate in performing laser induced breakdown spectroscopy.

58. The apparatus of claim 39 wherein the laser beam is adapted to remove material;

and

wherein the spectroscopy device is adapted to determine at least one chemical characteristic of the earth formation substantially concurrently with the laser beam removing material of the earth formation.

59. The apparatus of claim 39 further comprising a fluid outlet adapted to direct a fluid to at least partially overlap with the laser beam.

60. The apparatus of claim 59 wherein the fluid outlet is adapted to direct a fluid substantially coaxially with the laser beam.

61. The apparatus of claim 59 wherein the fluid outlet is adapted to direct the fluid to transmit at least one of the laser beam or the light emitted at least partially between the wall of the well bore and the device.

62. The apparatus of claim 39 wherein the laser beam device is adapted direct the laser beam into the well bore and further comprising a fluid outlet adapted to direct a fluid to impinge on a surface of the well bore.

63. The device of claim 62 wherein the fluid outlet is adapted to direct the fluid to at least one of at least partially clean a filter cake from the surface of the well bore or displace debris.

64. The device of claim 39 wherein the spectroscopy device is adapted to receive the light emitted from within a chamber of the apparatus.

183. The apparatus of claim 39 further comprising a plurality of optical fibers adapted to direct the laser beam in two or more trajectories into the wall of the well bore.

189. The apparatus of claim 55 wherein the laser beam device is operable to adjust an operation of the laser beam in relation to at least one of the specific heat, thermal conductivity, or thermal diffusivity.

192. The method of claim 183 wherein the operation adjusted comprises at least one of an energy, a power, a frequency, a duty cycle, a trajectory, and a focal point of the laser beam.

65. A method comprising:

heating the material within a well bore to cause at least a portion of the material to emit light;

receiving at least a portion of the emitted light; and

determining at least one chemical characteristic of the material from the emitted light.

66. The method of claim 65 wherein heating the material comprises directing a laser beam into a wall of the well bore.

67. The method of claim 66 further comprising generating the laser beam inside of the well bore.

68. The method of claim 66 wherein directing the laser beam onto the wall of the well bore comprises directing the laser beam onto the wall of the well bore in at least two different trajectories.

69. The method of claim 65 further comprising removing at least a portion of the material to at least one of form a perforation in the wellbore or drill the wellbore.

70. The method of claim 65 further comprising removing at least a portion of the material with a laser beam;

and

adjusting a focal length of the laser beam longer as a depth of the material removed increases.

71. The method of claim 66 further comprising deploying a light path in the wellbore;

and

wherein directing the laser beam into the material comprises directing the laser beam through the light path.

72. The method of claim 71 wherein deploying the light path further comprises extending the light path into a perforation being formed.

73. The method of claim 71 further comprising sensing at least one of pressure or temperature about the extended light path.

74. The method of claim 73 further comprising determining at least one of specific heat, thermal conductivity, or thermal diffusivity from the measurement.

75. The method of claim 65 wherein determining at least one chemical characteristic from the emitted light comprises performing laser induced breakdown spectroscopy.

76. The method of claim 65 further comprising removing at least a portion of the material;

and

wherein determining at least one chemical characteristic is performed substantially concurrently with removing at least a portion of the material.

77. The method of claim 65 further comprising directing a fluid to at least partially overlap with the emitted light.

78. The method of claim 77 wherein directing a fluid comprises directing the fluid substantially coaxially with the emitted light.

79. The method of claim 77 wherein the fluid is adapted to transmit at least one of the laser beam or the emitted light.

80. The method of claim 65 further comprising directing a fluid to impinge on a surface of the well bore.

81. The method of claim 80 wherein directing the fluid to impinge on a surface comprises directing the fluid to at least one of at least partially clean a filter cake from the surface of the well bore or displace debris.

82. The method of claim 65 further comprising collecting a sample of the material within an analysis tool in the well bore;

and

wherein receiving at least a portion of the emitted light comprises receiving at least a portion of the emitted light from within the chamber.

184. The method of claim 65 wherein directing the laser beam into the wall of the well bore further comprises directing the laser beam through a first optical fiber adapted to direct the laser beam in a first trajectory into the wall of the well bore and directing the laser beam through a second optical fiber adapted to direct the laser beam in a second trajectory into the wall of the well bore.

191. The method of claim 66 further comprising adjusting an operation of the laser beam in relation to at least on of a specific heat, thermal conductivity or thermal diffusivity of the material.

83. An apparatus for use in analyzing an earth formation defining a well bore, wherein at least a portion of the earth formation is heated within the well bore to emit light, the apparatus comprising:

an emitted light receiver adapted for insertion into the well bore and adapted to receive the light emitted from the formation; and

a spectroscopy device adapted to detect at least one of a presence, absence or intensity of one or more wavelengths of the light emitted from the formation.

84. The apparatus of claim 83 further comprising a laser beam device adapted to direct a laser beam into the earth formation, the laser beam adapted to heat at least a portion of the earth formation.

85. The apparatus of claim 84 wherein the laser beam device is adapted to generate the laser beam in the well bore.

86. The apparatus of claim 84 wherein the laser beam device is outside of the well bore.

87. The apparatus of claim 84 wherein the laser beam is adapted to remove material from at least one of a casing, a cement layer of the well bore, or the formation.

88. The apparatus of claim 87 further comprising a focusing array adapted to adjust a focal length of the laser beam longer as a depth of the material removed increases.

89. The apparatus of claim 84 further comprising a focusing array adapted to adjustably focus the laser beam on the material being removed.

90. The apparatus of claim 84 further comprising a laser beam directing device adapted to adjust the trajectory of the laser beam.

91. The apparatus of claim 90 wherein the laser beam directing device comprises a reflector.

92. The apparatus of claim 91 wherein the laser beam directing device comprises a dichroic reflector adapted to reflect at least one wavelength of the laser beam and allow passage of at least one wavelength of the light emitted from the formation;

and

wherein the emitted light receiver is adapted to receive at least a portion of the emitted light passed through the dichroic reflector.

93. The apparatus of claim 83 further comprising an extendable light path adapted to be extended outward into the well bore and adapted to transmit the light emitted from the earth formation toward the emitted light receiver.

94. The apparatus of claim 93 wherein the extendable light path is adapted to be extended into a perforation in the well bore.

95. The apparatus of claim 93 further comprising at least one sensor on the extendable light path adapted to be extended outward into the well bore with the light path.

96. The apparatus of claim 95 wherein the sensor is adapted to measure at least one of specific heat, thermal conductivity, or thermal diffusivity.

97. The apparatus of claim 83 further comprising a fluid outlet adapted to direct a fluid to at least partially coincide with the emitted light.

98. The apparatus of claim 97 wherein the fluid outlet is adapted to at least one of direct a fluid to form a substantially continuous fluid-based path between the earth formation and at least a portion of the apparatus or withdraw a fluid between the earth formation and at least a portion of the apparatus.

99. The apparatus of claim 97 wherein the fluid outlet is coupled to a source of fluid, the fluid comprising a liquid and a weighting agent.

100. The apparatus of claim 97 wherein the fluid outlet is adapted to direct the fluid substantially coaxially with emitted light received by the emitted light receiver.

101. The apparatus of claim 97 wherein the fluid is pulsed to at least partially coincide with the emitted light at least while the emitted light receiver is receiving emitted light.

102. The apparatus of claim 97 wherein the fluid outlet is adapted to direct the fluid to at least one of clean a surface of the earth formation or displace debris.

103. The apparatus of claim 83 further comprising a fluid outlet adapted to at least one of direct a fluid to clean a surface of the earth formation or displace debris.

104. The apparatus of claim 84 further comprising a fluid outlet adapted to direct a fluid to at least partially coincide with at least one of the laser beam or the light emitted from the formation.

105. The apparatus of claim 84 wherein the fluid outlet is adapted to direct a fluid substantially coaxially with the laser beam.

106. The apparatus of claim 84 wherein the laser beam is adapted to heat the earth formation to emit light by generating a first laser beam adapted to vaporize a fluid about the earth formation to form a cavity and generating a second laser beam adapted to heat at least a portion of the earth formation coinciding with the cavity to emit light.

185. The apparatus of claim 84 further comprising a plurality of optical fibers oriented to direct the laser beam into the earth formation in two or more trajectories.

193. The apparatus of claim 84 wherein the laser beam device is operable to adjust an operation of the laser beam in relation to at least one of a specific heat, thermal conductivity, or thermal diffusivity of the formation.

194. The apparatus of claim 84 wherein the laser beam device is operable to adjust at least one of an energy, a power, a frequency, a duty cycle, a trajectory, and a focal point of the laser beam.

107. A method of analyzing an earth formation comprising:

inserting an assembly into a well bore in an earth formation, the assembly having a material removal device adapted to remove material and an analysis device adapted to determine at least one chemical characteristic of material;

removing material from at least one of a sidewall or a end wall of the well bore using the material removal device;

heating the earth formation to emit light; and

without removing the assembly from the well bore, determining at least one chemical characteristic of the earth formation from the emitted light using the analysis device.

108. The method of claim 107 wherein removing material comprises at least one of perforating the well bore or drilling the well bore.

109. The method of claim 107 wherein removing material comprises at least one of directing a laser into the earth formation, operating a drilling bit, operating a coring bit, or operating a shaped charge or bullet perforating tool.

110. The method of claim 107 wherein removing material from the earth formation comprises directing a laser into the earth formation;

and

wherein the laser is adapted to heat the earth formation to emit light.

111. The method of claim 107 wherein determining at least one chemical characteristic of the earth formation is performed substantially concurrently with removing material.

112. The method of claim 107 wherein determining at least one chemical characteristic of the earth formation comprises determining at least one chemical characteristic of the earth formation in a first axial location in the well bore and determining at least one chemical characteristic of the earth formation in a second axial location in the well bore.

113. The method of claim 107 further comprising selecting one or more well sites based at least in part on the at least one chemical characteristic.

114. The method of claim 107 further comprising modifying the material removal based at least in part on the at least one chemical characteristic.

115. A device for removing material of an earth formation comprising:

a laser device adapted to output a laser beam, the laser beam adapted to remove material of the earth formation; and

a laser directing device adapted for insertion into a borehole and adapted to direct the laser to remove material of the earth formation in a first area and a second area without substantially repositioning the laser device.

116. The device of claim 115 wherein the laser directing device comprises a reflector coupled to a servo, the servo adapted to move the reflector.

117. The device of claim 115 wherein the laser directing device is adapted to direct the laser in a plurality of trajectories.

118. The device of claim 115 wherein the laser directing device is adapted to direct the laser to form at least one of a circumferentially oriented groove, an axially oriented groove, or a conical hole in the earth formation.

119. The device of claim 115 wherein the laser directing device is adapted to direct the laser to form a hole in the earth formation and, at least one of concurrently while forming the hole or subsequent to forming the hole, widen the hole in the earth formation.

120. The device of claim 115 wherein the laser directing device is adapted to direct the laser to remove material of the earth formation at two or more locations on the earth formation substantially concurrently.

121. The device of claim 120 wherein the laser directing device is adapted to direct the laser at a first of the at least two locations in a first duty cycle that is less than one and direct the laser to a second of the at least two locations during an off cycle of the first duty cycle.

186. The device or claim 115 wherein the laser directing device comprises a plurality of optical fibers adapted to direct the laser beam to at least the first area and the second area.

122. A method of removing material about a well bore, comprising:

inserting a tool adapted to direct a laser beam into the well bore;

directing the laser beam into the well bore in a first trajectory to remove material in a first area; and

without moving the tool, directing the laser beam into the well bore in one or more additional trajectories different from the first trajectory to remove material in one or more additional areas.

123. The method of claim 122 wherein at least one of the one or more additional areas does not coincide with the first area.

124. The method of claim 122 wherein directing the laser into the well bore in one or more additional trajectories comprises directing the laser in one or more trajectories adapted to form at least one of a circumferentially oriented groove, an axially oriented groove, or a conical hole in the earth formation.

125. The method of claim 122 wherein directing the laser into the well bore comprises reflecting the laser off a reflector movable to direct the laser in one or more trajectories.

126. The method of claim 122 wherein directing the laser into the well bore in the first trajectory comprises directing the laser in the first trajectory during a first duty cycle that is less than one;

and

wherein directing the laser into the well bore in one or more additional trajectories comprises directing the laser in the one or more additional trajectories during an off cycle of the first duty cycle.

187. The method of claim 122 wherein directing the laser beam in a first trajectory comprises directing the laser beam through a first optical fiber adapted to direct the laser beam in the first trajectory.

188. The method of claim 187 wherein directing the laser beam in one or more additional trajectories comprises directing the laser beam through one or more additional optical fibers adapted to direct the laser beam in the one or more additional trajectories.

127. An apparatus for insertion into a well bore defined in an earth formation, comprising:

a housing adapted for insertion into a well bore; and

a light path adapted to displace less optically transmissive material in the well bore and to transmit light at least part way between the housing and the earth formation.

128. The apparatus of claim 127 wherein the light path comprises at least one of a fluid, at least one fiber optic, or a substantially evacuated passage.

129. The apparatus of claim 127 further comprising at least one of a laser device adapted to output a laser beam or an emitted light receiver adapted to receive light emitted by a heated material.

130. The apparatus of claim 129 wherein the light path comprises a fluid and the apparatus further comprises a fluid outlet adapted to direct the fluid to at least partially coincide with at least one of the laser beam or the light emitted by the earth formation.

131. The apparatus of claim 130 wherein the fluid outlet is adapted to direct the fluid substantially perpendicular to a wall of the well bore.

132. The apparatus of claim 130 wherein the fluid outlet is adapted to direct the fluid to at least one of substantially clean a surface of the earth formation or displace debris.

133. The apparatus of claim 130 wherein the fluid comprises at least one of water, oil, or a substantially transparent weighting agent.

134. The apparatus of claim 130 further comprising a fluid reservoir positioned at least partially within the housing.

135. The apparatus of claim 127 further comprising a distance meter adapted to determine a distance between the apparatus and the earth formation with a laser;

and

wherein the laser used in measuring the distance at least partially coincides with the light path.

136. The apparatus of claim 127 wherein the light path is extendable outward from the housing.

137. The apparatus of claim 127 wherein the light path comprises a fiber optic extendable outward from the housing.

138. The apparatus of claim 137 wherein the fiber optic is extendable into a perforation in the earth formation.

139. The apparatus of claim 137 further comprising a sensor on the fiber optic for sensing at least one of pressure or temperature.

140. The apparatus of claim 127 further comprising a tubular snorkel extendable outward from the housing;

and

wherein the light path passes through the tubular snorkel.

141. The apparatus of claim 140 wherein the tubular snorkel is adapted to substantially seal with a wall of the well bore.

142. The apparatus of claim 141 wherein an interior of tubular snorkel is substantially evacuated to define the light path.

143. The apparatus of claim 140 wherein the tubular snorkel comprises an elastomeric body at least one of inflated or extruded to extend outward from the housing.

144. The apparatus of claim 127 further comprising a spectroscopy device adapted to receive light emitted from the earth formation and perform spectroscopy on the emitted light.

145. The apparatus of claim 127 further comprising:

a first seal adapted to seal an annulus between the housing and the well bore; and

wherein the light path comprises a fluid in the annulus downhole of the first seal.

195. The apparatus of claim 127 further comprising:

a first seal adapted to seal an annulus between the housing and the well bore;

a second seal offset from the first seal and adapted to seal the annulus between the housing and the well bore; and

wherein the light path comprises a fluid introduced into the annulus between the first and second seals.

146. A method of communicating light between a device positioned in a well bore defined in an earth formation and the earth formation, comprising:

displacing less optically transmissive material within the well bore with an optically transmissive light path positioned between a housing of the device and the earth formation; and

transmitting light at least part way between the earth formation and the device with the optically transmissive light path.

147. The method of claim 146 wherein displacing less optically transmissive material with an optically transmissive light path comprises positioning at least one of a fluid, at least one fiber optic, or a substantially evacuated passage between the device and the earth formation.

148. The method of claim 146 wherein transmitting light with the optically transmissive light path comprises at least one of transmitting a laser beam to the earth formation or transmitting light emitted from the formation to the device.

149. The method of claim 146 wherein displacing less optically transmissive material with an optically transmissive light path comprises directing a fluid substantially perpendicular to a wall of the well bore.

150. The method of claim 146 wherein displacing less optically transmissive material with an optically transmissive light path comprises directing a fluid to flow between the device and the earth formation and to at least one of substantially clean a surface of the earth formation or displace debris.

151. The method of claim 146 wherein displacing less optically transmissive material with an optically transmissive light path comprises directing a fluid to flow between the device and the earth formation, the fluid comprising at least one of water, oil, or a substantially transparent weighting agent.

152. The method of claim 146 wherein transmitting light at least part way between the earth formation and device with the optically transmissive light path comprises transmitting a laser beam used in determining a distance between the earth formation and the device.

153. The method of claim 146 wherein displacing less optically transmissive material with an optically transmissive light path comprises extending the light path outward from a housing of the device and into the well bore.

154. The method of claim 146 wherein displacing less optically transmissive material with an optically transmissive light path comprises extending a fiber optic outward from a housing of the device and into the well bore.

155. The method of claim 154 wherein extending a fiber optic outward from the housing comprises extending the fiber optic into a perforation in the earth formation.

156. The method of claim 146 further comprising extending a tubular snorkel outward from a housing of the device and into the well bore;

and

wherein displacing less optically transmissive material with an optically transmissive light path comprises positioning the light path within the tubular snorkel.

157. The method of claim 156 wherein displacing less optically transmissive material with an optically transmissive light path comprises substantially evacuating an interior of the tubular snorkel to define the light path.

158. The method of claim 156 wherein extending the tubular snorkel comprises at least one of inflating or extruding an elastomeric body.

159. The method of claim 146 wherein displacing less optically transmissive material within the well bore with an optically transmissive light path comprises:

actuating a seal to substantially seal an annulus between the housing and the well bore; and

receiving an optically transmissive fluid between the housing and the well bore and beyond the seals, the optically transmissive fluid adapted to displace fluid adjacent the seal.

196. The method of claim 146 wherein displacing less optically transmissive material within the well bore with an optically transmissive light path comprises:

actuating a first seal to substantially seal an annulus between the housing and the well bore, the first seal offset from a second seal;

introducing an optically transmissive fluid between the housing and the well bore and between the first and second seals; and

actuating the second seal to substantially seal the annulus between the housing and the well bore.

160. A well feedback system comprising:

an emitted light receiver insertable into a well bore and adapted to receive light emitted from material within the well bore that has been heated to emit light;

an emitted light analysis device adapted to determine at least one of a chemical or a physical characteristic of the material from the emitted light; and

a tool for performing a function related to the well, an operation of the tool being adjusted in relation to at least one of the chemical or the physical characteristic determined by the emitted light analysis device.

161. The system of claim 160 wherein the tool is a material removal tool adapted to remove material in the well bore and wherein the operation adjusted comprises at least one of the location, the direction or the rate of material removal.

162. The system of claim 161 wherein the operation adjusted is adjusted to at least one of adjust material removal efficiency or adjust formation exposure.

163. The system of claim 160 wherein the physical characteristic comprises at least one of lithology, formation hardness, competency, porosity, thermal conductivity, thermal diffusivity, specific heat or permeability.

164. The system of claim 160 wherein the tool is a laser tool adapted to remove material in the well bore using a laser beam and wherein the operation adjusted comprises at least one of the energy, power, frequency, duty cycle, trajectory or focal point of the laser beam.

165. The system of claim 164 wherein the operation adjusted is adjusted to at least one of adjust material removal efficiency or adjust formation exposure.

166. The system of claim 160 wherein the tool is a laser tool adapted to heat material to emit light using a laser beam and wherein the operation adjusted comprises at least one of the energy, power, frequency, duty cycle, trajectory or focal point of the laser beam.

167. The system of claim 166 wherein the operation adjusted is adjusted to improve the determine at least one of a chemical or a physical characteristic of the material from the emitted light.

168. The system of claim 160 further comprising a distance measuring device and wherein the operation of the tool is adjusted further in relation to a distance measured by the distance measuring device.

169. The system of claim 168 wherein the operation of the tool is adjusted further in relation to a plurality of distance measurements measured by the distance measuring device.

170. A method of operating a well tool comprising:

receiving emitted light from material within the well bore, the material having been heated to emit light; and

adjusting operation of the well tool in relation to the received emitted light.

171. The method of claim 170 further comprising analyzing the emitted light to determine at least one of a chemical or a physical characteristic of the material.

172. The method of claim 170 wherein receiving emitted light and adjusting operation of the well tool is performed concurrently.

173. The method of claim 170 wherein the well tool is a material removal tool and adjusting operation of the well tool comprises adjusting at least one of the location, the direction or the rate of material removal.

174. The method of claim 170 wherein the operation is adjusted to at least one of adjust material removal efficiency or adjust formation exposure.

175. The method of claim 170 wherein the well tool is a laser tool adapted to direct a laser beam into a wall of a well bore and adjusting operation of the well tool comprises adjusting at least one of the energy, power, frequency, duty cycle, trajectory, or focal point of the laser beam.

176. The method of claim 175 wherein the laser beam is adapted to remove material and the operation is adjusted to change the material removal mode.

177. The method of claim 175 further comprising analyzing the emitted light to determine at least one of a physical or chemical characteristic of the material;

and

wherein the laser beam is adapted to heat material to emit light and the operation is adjusted to adjust the determination of the characteristic.

178. The method of claim 170 wherein the well tool is a drilling tool and wherein adjusting operation of the well tool in relation to the received emitted light comprises adjusting drilling operations to drill an additional well bore selected in relation to the emitted light.

179. The method of claim 170 wherein the well tool is a perforating tool and wherein adjusting operation of the well tool in relation to the received emitted light comprises adjusting perforating operations to perforate the well bore in additional locations selected in relation to the emitted light.

180. The method of claim 170 further comprising determining a temperature of the emitted light and adjusting the operation of the well tool in relation to the determined temperature.