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Table T4. Key parameters for Hole 1256D and preliminary subdivisions of the upper oceanic crust, Site 1256.

Location: 6°44.163'N, 91°56.061'W
Water depth (m): 3634.7
Sediment thickness (m): 250
16 inch casing string (m): 269.5
Interval in Hole 1256D drilled during
ODP Leg 206: 752 mbsf (502 msb)
IODP Expedition 309: 1255.1 mbsf (1005.1 msb)





Subdivision
Core, section,
interval (cm)
Igneous unit
Depth (mbsf)
Criteria





Lava pond
 		206-1256D-2R-1, 0 cm
 		1256D-1
(1256C-1 through 18)
 		~250
 		Massive ponded lava and overlying sheet flows
Inflated flows
 		206-1256D-13R-1, 0 cm
 		1256D-2
 		350.3
 		Massive, sheet, and pillowed flows with inflation features
Sheet and massive flows
 		206-1256D-43R-1, 0 cm
 		1256D-16
 		533.9
 		Sheet flows with subordinate massive flows
Transition zone
 		309-1256D-117R-1, 85 cm
 		1256D-40
 		1004.2
 		Sheet flows with breccias, rare dikes, and alteration at (sub-)greenschist facies conditions
Sheeted intrusives
 		309-1256D-129R-1, 0 cm
 		1256D-44a
 		1060.9
 		Massive basalts, common subvertical intrusive contacts. Elevated VP and TC.
Expedition 309 maximum depth
 		309-1256D-170R-3, 89 cm
 		1256D-65
 		1255.5
 		(n.b. curated depth)





Notes: VP = P-wave velocity, TC = thermal conductivity, n.b.

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