SPECMAP Archive #3: Specmap3.readme
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               World Data Center A- Paleoclimatology
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NOTE: PLEASE CITE ORIGINAL REFERENCES WHEN USING THIS DATA!!!!!


NAME OF DATA SET:  SPECMAP Archive #3
LAST UPDATE:  9/93  (Original receipt date by WDC-A Paleo) 
CONTRIBUTORS:  J. Imbrie, et al., Brown University
IGBP PAGES/WDCA Data Contribution Series #:  93-023
SUGGESTED DATA CITATION: 
Imbrie, J. et al., 1993, SPECMAP Archive #3.  IGBP PAGES/World Data Center-A
for Paleoclimatology Data Contribution Series # 93-023.  
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA.

ORIGINAL REFERENCES:
J.Imbrie, A.C.Mix, and D.G.Martinson, 1993, Milankovitch Theory Viewed 
from Devils Hole, NATURE, May, 1993.

The orbital theory of Pleistocene climate: Support from a revised 
chronology of the marine O-18 record, in 'Milankovitch and Climate, 
Part 1', edited by A.Berger et al.,1984.  


GEOGRAPHIC REGION: Global
PERIOD OF RECORD: 0 - 400,000 YBP
LIST OF FILES: 10 data files.  See file Archive3.con for descriptions
DESCRIPTION:
The files making up this archive represent analytical results and data 
which formed the basis for the discussion of the Devils Hole calcite 
record, DH-11, in the original reference.  The first figure in this paper 
shows the ice volume record as portrayed by the SPECMAP stack, in 
two different chronologies.  The file STCKPM11.DAT, included in 
this archive, is based on the chronology developed by the SPECMAP 
group and published in Imbrie et al, 1984.  The file STCKPM11.DH1 
gives the same stacked record but with ages based on the DH-11 
calcite record.  The core DH-11 starts at 60ka, and so SPECMAP ages 
are used from the present to 60ka in this file.  The mapping function 
(figure 2) for transforming the SPECMAP chronology to that of DH-11 
is given in the file STCKDH11.MAP. The first column gives 
SPECMAP age and the second column, the corresponding DH-11 age.  
The files RC1311DH.MAP, V238DH11.MAP, V3040DH.MAP, and 
RC1112DH.MAP provide the information used to produce the age vs 
depth plots of figure 3.  In each file, the third column is sample depth.  
The first column gives the SPECMAP age assigned to  that depth, and 
the second column, the DH-11 age for that depth.  The O-18 records 
for these cores are available in other SPECMAP archives.  O-18 for 
core V30-40 is included in SPECMAP Archive 1. The O-18 records 
for RC13-110 and RC11-120 are given in Archive 2.  The file 
V28238P1.STR, included in this archive, gives O-18 for core V28-238 
as a function of depth and age.  Figure 4 shows spectra of the two O-
18 records, SPECMAP and DH-11.  Also shown is the spectrum of 
insolation for June at 65N.  Although this file is included in Archive 2, 
it is repeated here, and has the file name Q65N1990.INS.