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Table T3. Summary of APC overdrilling.

Hole

Depth of first excess force (mbsf)

Maximum APC penetration (mbsf)

Added APC penetration by overdrilling (%)

Reason for APC termination

Number of overdrilled APC barrels

APC
cores

XCB
cores

Total penetration (mbsf)

1232A

103

112.5

9

B2

2

12

27

371.3

1232B

A2

10

90.1

1232C

A2

4

33.2

1233A

A1

1

12.0

1233B

A1

11

109.5

1233C

A1

13

116.3

1233D

A1

13

112.3

1233E

A1

8

101.5

1234A

B1

11

11

205.2

1234B

B1

10

9

182.4

1234C

A2

8

79.1

1235A

B1

20

181.3

1235B

B1

19

176.2

1235C

A2

16

152.5

1236A

A2

20

4

207.7

1236B

C

13

122.8

1236C

154.8

167.3

8

A2

1

18

167.3

1237A

A2

1

10.5

1237B

148

317.4

114

B1

16

34

317.4

1237C

163.3

315.3

93

B1

15

33

315.3

1237D

234

253

8

A2

3

11

253.0

1238A

90.5

204.5

126

B1

10

22

24

430.6

1238B

87

201

131

B1

8

21

201.0

1238C

139

167.5

21

A2

3

18

167.5

1239A

88.9

174.4

96

B2

6

19

36

515.4

1239B

152.3

171.3

12

B2

3

18

24

398.7

1239C

A2

12

117.3

1240A

174.5

253

45

B1

6

28

253.0

1240B

162.7

248.2

53

B1

8

26

248.2

1240C

A2

8

80.2

1240D

A2

3

31.7

1241A

184.4

314.2

70

B1

13

34

9

394.4

1241B

200.4

259.4

29

B2

7

27

5

395.0

1241C

A2

11

143.5

1242A

B1

19

8

250.8

1242B

B1

18

9

256.0

1242C

A2

18

172.0

1242D

A2

8

91.5

Average* (%):

77

Notes: APC = advanced hydraulic piston corer. Reason for APC termination: A1 = Pollution Prevention and Safety Panel approved depth is reached, A2 = mission accomplished, B1 = incomplete stroke is indicated, B2 = excessive pull out force >100 klb, C = mechanical. * = average from holes with APC refusal.

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