MAGNETIC SUSCEPTIBILITY

I. INTRODUCTION

The Susceptibility data file contains the susceptibility measurements taken onboard JOIDES Resolution. A Bartington M.S.1 Magnetic Susceptibility meter on the ship can measure discrete samples or whole core sections passed through the instrument's sensor loop.

The data are collected directly from the susceptibility meter onto the shipboard VAX computer and brought back to shore on magnetic tape. These data files contain measurements made on whole core sections.

II. BIBLIOGRAPHY

Shipboard Scientific Party, 1987. Explanatory Notes. in Srivastava,S. P., Arthur, M. A., Clement, B. M., et al., Proc., Init. Repts.(Pt A), ODP, 105.

III. DATA ITEM FORMATS

LEG
SITE
HOLE
CORE
CORETYPE
SECTION
TOP_INTERVAL
BOTTOM_INTERVAL
SUB_BOTTOM_DEPTH
SUSCEPTIBILITY
RUN_NUMBER

IV. EXPLANATION OF THE SUSCEPTIBILITY DATA ITEMS

LEG - Number identifying the cruise.

SITE - Number identifying the site. A site is the position of a beacon around which holes are drilled.

HOLE - Letter identifying the hole.

CORE - Number identifying the core. Cores are numbered serially from the top of the hole downward.

CORETYPE - A letter code identifying the drill bit/coring method used to retrieve the core. The coretype codes are:

B - Drill Bit
C - Center Bit
D - Positive Displacement
H - Hydraulic Piston Core
M - Miscellaneous
N - Downhole Mud Motor (Navidrill)
P - Pressure Core Barrel
R - Rotary
S - Side Wall Core
W - Wash Core
X - Extended Core Barrel

SECTION - A core is cut into 1.5 meter long sections that are numbered serially from the top of the core. A core with full recovery will have 7 sections and a core catcher and be approximately 9.8 meters long.

TOP_INTERVAL - The location of the top of a sample within a section in centimeters.

BOTTOM_INTERVAL - The location of the bottom of a sample within a section in centimeters.

SUB_BOTTOM_DEPTH - Distance in meters from the seafloor to the top of the sample interval.

SUSCEPTIBILITY - The value is in x10-6 cgs units and is volume corrected.

RUN_NUMBER - Each run of the MST is given a number which increments by one with every test.