Filename=akdata.rtf

Organic Geochemistry Data of Alaska
Database Documentation

By Charles N. Threlkeld1 and Raymond C. Obuch2 

1USGS Central Region Energy Team
Box 25034, MS 977
Denver, CO 80225
http://energy.cr.usgs.gov
cthrelkeld@usgs.gov

2USGS Central Region Energy Team
Box 25034, MS 939
Denver, CO 80225
obuch@usgs.gov

Any use of trade, product or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U. S. Government.

CONTENTS

Overview and Background							
Relational Database Tables, Structures and Definitions	
Index and Encoding Schemes									
Appendix A -- Definitions of Some Commonly Used Terms		
Appendix B -- Manufacturers of Products and Services Mentioned	

OVERVIEW AND BACKGROUND

	The U.S. Geological Survey (USGS) Central Energy Resources Team’s Organic Geochemistry Laboratory (CERTOGL) is a research laboratory devoted to the investigation of the origin and occurrence of fossil fuels. One such study involved the petroleum potential of the National Petroleum Reserve in Alaska (1988). In order to archive geochemical results of this study, the USGS developed an Alaskan Organic Geochemical Database (AOGDB) in 1978 to house the data generated from USGS laboratories and various sub-contracted laboratories.  The accumulated data resided in a flat text file entitled “PGS” and was originally maintained by Petroleum Information Corporation.  The information herein is a breakout and creation of tables from the master flat file form into a relational database format.  No electronic data, such as chromatograms, are available for this data file. Additional information about “PGS” and Alaska geochemistry data and interpretation can be obtained in Geology and Exploration of the National Petroleum Reserve in Alaska, 1974-1982, USGS Professional Paper 1399 (see the sections by Claypool and Magoon, p. 451-481, and Magoon and Claypool, p. 519-549.)

	The database management software originally used in the creation of the AOGDB is MicroRim Corporation's RBase for DOS, a database package designed for use on IBM XT or AT or equivalent computers with MS-DOS or equivalent disk operating systems. The AOGDB consists of Rbase tables, which have subsequently been converted to Microsoft Access 97 tables and ASCII tables. Each table consists of vertical columns and horizontal rows of information where each row represents one sample and the columns within each row represent specific information about the sample. There is only one driving table: HEADER_PGS, which contains generic sample information and permits a relational pathway to the data tables via the primary key: WMO (derived from World Meteorological Organization and the American Petroleum Institute; see below.)

	There can be any number of data tables, one for each analytical technique that produces data in some numeric format. The USGS AOGDB has 19 data tables and one legend table that attempts to correlate tabular information back to the original PGS notations.  Additionally, five other tables exist from which a number of elements were transferred to form parts of the HEADER_PGS table.  The tables below are the breakout products of the PGS flat file.

HDSP_13c_40_PGS 	13C, D, and 34S stable isotopes of headspace gas.
WHLOIL_13C_65_PGS		13C stable isotopes of whole oils.	
SAT_ARO_13C_39_PGS	13C stable isotopes of saturate and aromatic fractions.
COMMENTS_PGS			Sample/analytical comments.
ELEM_36_PGS	Weight percent carbon, nitrogen, hydrogen and ash.
ELEM_37_PGS			Weight percent oxygen, sulfur, and ash.
FRAC_2930_PGS	Weight percent saturates, aromatics, and non-hydrocarbon fractions.
CANGAS_8081_PGS			Chemical analyses of canned headspace gas.
GASRNG_23_PGS	C5–C8 gasoline range components by gas chromatography.
GC_3162_PGS	C7-C35 paraffin range components by gas chromatography.
HEADER_PGS	Location, lithology, age, and rock unit information.
ISOT_38_PGS			34S, 15N Stable isotopes of saturates and ashpaltenes.
LEGEND_PGS	Correlates to PGS analytical tables (contained herein).
MASTER_PGS	Every code in the data file and the COMMENTS_PGS comments field.  
RKEV_41_PGS			Standard Rock-Eval pyrolysis data.
SPGR_60_PGS			Specific gravity of oils.
TAI_35_PGS				Thermal alteration index of macerals.
TC_TOC_2728_PGS	Weight percent total carbon and total organic carbon values.
TEAFID_26_PGS   	Percent volatiles, tmax, and hydrocarbon yield (thermal evolution analysis).
VISKER_34_PGS			Visual kerogen analysis.
VITREF_33_PGS			Vitrinite reflectance analysis.

	Please note that throughout the text part of this document UNDERLINED words are actual table names and BOLD words are table elements (field/column titles).

	The data tables are structured such that the first four columns of each data table are identical in structure and provide a linking "key" to the HEADER_PGS table. Note that the column entitled RC_* is not present in the HEADER_PGS table but exists in all the Data tables.  The internal "key" for the AOGDB is the WMO reference number. 
	The WMO number is a concatenation of four basic components: WSC UNIQ HCST and SEQ and is derived by combining the World Meteorological Organization’s global quadrant naming convention with the American Petroleum Institute’s naming convention for wells.  Please also note that the API number for wells lies between the second and fifteenth position of the WMO number. The following explains the formation of the WMO number: (note: these are not table elements)

	1. WSC (World, State, County).  Text field formed by the World State County combined codes of the WMO number. Samples collected within the U.S.A (including Alaska, Hawaii, and its Exclusive Economic Zones (EEZ)) are identified by the world quadrant number of “9,” then a two digit state code followed by a three digit county code. In instances of samples received outside the U.S.A or the EEZ, the State and county codes become pseudo State and county codes by substituting two digits of latitude for the State code and three digits of longitude for the county code. The six digits in the WSC are the first 6 digits in the WMO number.
	2. UNIQ (unique well number).  The unique part of an API well number.  In the case of outcrops, the UNIQ value becomes a serial five-digit number greater than 94999.  The UNIQ part of the WMO number contains five digits beginning at the 7th position of the WMO number.
	3. HCST (hole change side track).  Side Track and Hole Change.  The HCST field consists of four digits and begins at the 12th position of the WMO number.  It is normally “0000.”
	4. SEQ (sequence).  The last four digits of the WMO number.  Provides for multiple (9999) samples from one location.  This part begins at the 16th position of the WMO number.

The data types used in the following tables are: 
	
	Type			Character length

	Text			0-255
	Integer			1-9
	Real			1-9
	Double			1-16

Relational Database Tables, Structures, and Definitions

To minimize the database size, many text fields are encoded.  Refer to the section Encoding Schemes on page 30 for more information.

	Table HEADER_PGS contains information about the sample including latitude, longitude, location, elevation, depth, other location information, sample identification, sample type(s), lithology, formation names and ages, well and outcrop (surface) samples, and any additional information.  All of these data elements are contained in the HEADER_PGS table.  In addition, the table contains other information that may be used in data retrieval for specialized reports, charts, and maps.  HEADER_PGS contains information from a number of the original tables in the original PGS flat file.

Table HEADER_PGS column definitions (Record Count: 22,326)

#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO				Text				20
2	API				Text 				14
3	LABNO			Text				8
4	DI_B001			Text				6
5	M1				Text				1
6	TOP				Number (Double)		8
7	BOT				Number (Double)		8
8	STY				Text				2
9	CONTAINER		Text				6
10	ADDNL			Text				17
11	SAMPID			Text				40
12	ELEV			Text				10
13	TLD				Text				7
14	WELCLAS			Text				2
15	SRT				Text				10
16	LAT				Number (Double)		8
17	LONG			Number (Double)		8
18	FAGE			Text				4
19	FUNIT			Text				4
20	LC_R020			Text				4
21	LITHO1			Text				20
22	P1				Text				4
23	LITHO2			Text				20
24	P2				Text				4
25	LITHO3			Text				20
26	P3				Text				4
27	LITHO4			Text				20
28	P4				Text				4
29	CONTAM1			Text				20
30	CP1				Text				4
31	CONTAM2			Text				20
32	CP2				Text				4
33	POR				Text				1
34	SHO				Text				1
35	SWT				Text				4
		
Description of elements:

1	WMO   		Modified form of the API number. 
2	API		Unique American Petroleum Institute Well Number.    
3	LABNO 		Prime Contractor’s (USGS) Lab number.
4	DI_B001 	Date sample entered into system.  A login date.
5	M1  		Metric or English indicator units (depths, etc.)
6	TOP 		Top depth of sampled interval (if from a well).
7	BOT 		Bottom depth of sampled interval (or blank if spot 
					sample).
8	STY 	Sample source or type code (core, cuttings, gas, etc.)
9	CONTAINER	External/Internal condition (ec, ic, ad codes) of container.
10	ADDNL 		Additional comments, fieldnames, special ID’s.
11	SAMPID 	Sample identification: either a well number and name (if 
from a well database), or the submitter's field sample name [if an outcrop (surface) sample.]
12	ELEV 		Elevation of well or outcrop (units as in M1).
13	TLD 		Total depth (if from a well).
14	WELCLAS 	Well Class (unknown encoding scheme).
15	SRT 		For samples within the U.S., the Township direction 
	(D), Township (NNN), Range direction, Range, and section number in the following format: DNNNDNNNNN.
16	LAT 		Latitude, 5 decimals.
17	LONG 		Longitude, 5 decimals.
18	FAGE 		Formation age code.
19	FUNIT 		Formation name code.
20	LC_R020 	Lab Code Notation in PGS.
21	LITHO1 	Gross lithology #1 Encoded text field.
22	P1 		Percent of lithology #1.
23	LITHO2 	Gross lithology #2 Encoded text field.
24	P2 		Percent of lithology #2.
25	LITHO3 	Gross lithology #3 Encoded text field.
26	P3 		Percent of lithology #3.
27	LITHO4 	Gross lithology #4 Encoded text field.
28	P4 		Percent of lithology #4
29	CONTAM1 	Contaminant  #1 Encoded text field.
30	CP1 		Percent of contaminant #1.
31	CONTAM2 	Contaminant  #2 Encoded text field.
32	CP2 		Percent of contaminant #2.
33	POR 		Gross porosity code.
34	SHO 		Gross SHOW code.
35	SWT 		Sample Weight.

	The HEADER_PGS table contains one row per sample, each row comprised of all 35 columns as defined above.

	The table HDSP_13C_40_PGS contains data on the stable carbon isotopic signature (13C) of headspace gas.  The number “40” in the table references the old PGS code of 040 for this analysis. The leading 7 characters of the HDSP_13C_40_PGS table attempt to convey that this table consists of stable carbon isotopic values on headspace (HDSP) gas.

Table HDSP_13C_40_PGS column definitions (Record Count: 548)
   	
#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO	  		TEXT				20     
2	RC_R040  		TEXT       			7        
3	LC_R040  		TEXT       			4     
4	DO_R040  		TEXT       			6         
5	C13_HDSP 		TEXT       			8     

Description of the Elements:

1	WMO         	Modified form of the API number.      
2	RC_R040    	The old PGS record code for this analysis.  Note that 
the lower case “r” originally implied that the original sample fraction received into the lab was a rock sample.  In this instance, even though a gas sample was analyzed, it originated from the desorption of a canned core (rock) sample.	
3	LC_R040	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_R040	Assumed to be the date of completion of the analysis 
				or the date the data was encoded into the file.
5	C13_HDSP 	Parts per thousand  from the international standard 
(PeeDee Belemnite) PDB.  Note: Several isotope values were reported without the negative (“-“) notation.  These values were, in all likelihood, improperly keypunched into the system.  This observer thinks that in fact, no positive values exist in this data set.  No attempt has been made here to remedy this oversight.

The Table WHLOIL_13C_65_PGS contains information on the Stable Carbon Isotopes of Whole Oils.  The last six digits of the table name relate to the old PGS analytical code of 065 for this analysis.

Table WHLOIL_13C_65_PGS column definitions (Record Count: 112)
   	
#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO	  		TEXT				20       
2	RC_o065  		TEXT     			7    
3	LC_o065  		TEXT     			4       
4	DO_o065  		TEXT     			6      
5	13CWHOIL 		TEXT     			8      

Description of the Elements:

1	WMO 			Modified form of the API number.
2	RC_o065  	Old PGS record code for this analysis.  Note that 
	the lower case “o” implied that the original sample fraction received into the lab was an oil sample.
3	LC_o065  	A code depicting the subcontracting laboratory in 
				which the sample was analyzed.
4	DO_o065 	Assumed to be the date of completion of the analysis 
				or the date the data was encoded into the file.
5	13CWHLOIL 	Delta stable carbon isotopic value in parts per
	thousand  variance from that of the international standard: PDB.

	The table SAT_ARO_13C_39_PGS contains information on the Stable Carbon Isotopes of the C15+ saturate and C15+ aromatic hydrocarbon fractions of oils and rock extracts. This table is a combination of the old PGS r039 and o039 data tables. 

Table SAT_ARO_13C_39_PGS column definitions (Record Count: 805)
   
#	Field Name     	Data Type	 	Field Length (Characters) 
1	WMO	  		TEXT				20     
2	RC_039   		TEXT       		7         
3	LC_039   		TEXT       		4        
4	DO_039   		TEXT       		6        
5	C13_S15  		TEXT       		8      
6	C13_A15  		TEXT       		8      

Description of the Elements:

1	WMO 			Modified form of the API number.
2	RC_039 	The old PGS record code for this analysis.  Note that
	there exists no lower-case designation for (r)ock samples or (o)il samples as in other tables.  
3	LC_039 	A code depicting the subcontracting laboratory in 
				which the sample was analyzed. 
4	DO_039 	Assumed to be the date of completion of the analysis 
					or the date the data was encoded into the file.
5	C13_S15 	The delta 13C stable isotopic value in parts per 
	thousand variance from that of the international standard: PDB of the C15+ saturate fraction.
6	C13_A15 	The delta 13C stable isotopic value in parts per 
	thousand variance from that of the international standard: PDB of the C15+ aromatic fraction.

The table COMMENTS_PGS is a forum for the contracting lab to make statements regarding the sample condition, analytical technique, or to list problems encountered with the sample. Preserved in the table are the original API values before they were modified to WMO numbers. NOTE: The comment field of this table has been transferred to the MASTER_PGS table to facilitate the use of the comments field in data table lookups to insure the sample integrity.

Table COMMENTS_PGS column definitions (Record Count: 2,698)

#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO	  		TEXT				20        
2	API      		TEXT    			14  
3	SQ       		TEXT     			4        
4	RECNO    		TEXT     			7        
5	COMMENT  		TEXT     			40         
6	FILDTE   		TEXT     			6  

Description of the Elements:

1	WMO 		Modified form of the API number.
2	API  		The original API designation of the sample in PGS.
3	SQ  		The Original sequence number in PGS.
4	RECNO		The original record number in PGS.
5	COMMENT 	Any Comment regarding the sample.
6	FILDTE	  	Filing date of the comment.
              
The table ELEM_36_PGS contains information on the elemental composition of a sample including carbon, hydrogen, nitrogen, and ash.

Table ELEM_36_PGS column definitions (Record Count: 1,813)
											
#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO		    	Text				20
2	RC_R036		Text				7
3	LC_R036		Text				4
4	DO_R036		Text				6
5	WPCT_C			Number (Double)		8
6	WPCT_H			Number (Double)		8
7	WPCT_N			Number (Double)		8
8	WPCT_ASH		Number (Double)		8

Description of the Elements:

1	WMO  		Modified form of the API number.
2	RC_R036 	The old PGS record code for this analysis.
3	LC_R036	A code depicting the subcontracting laboratory in 
						which the sample was analyzed.
4	DO_R036	Assumed to be the date of completion of the analysis 
					or the date the data was encoded into the file.
5	WPCT_C  	Weight Percent carbon.
6	WPCT_H  	Weight Percent hydrogen.
7	WPCT_N  	Weight Percent nitrogen.
8	WPCT_ASH 	Weight Percent ash.

The table: ELEM_37_PGS contains information on the elemental composition of the sample including sulfur and oxygen.

Table ELEM_37_PGS column definitions (Record Count: 910)

#	Field Name     	Data Type	 	Field Length (Characters)         
1	WMO		    	Text				20
2	RC_R037		Text				7
3	LC_R037		Text				4
4	DO_R037		Text				6
5	WPCT_O			Number (Double)		8
6	WPCT_S			Number (Double)		8
7	ASH_WPCT		Number (Double)		8

Description of the elements:

1	WMO   		 Modified form of the API number.
2	RC_R036 	 The old PGS record code for this analysis.
3	LC_R036 	 A code depicting the subcontracting laboratory in 
						 which the sample was analyzed.
4	DO_R036 	 Assumed to be the date of completion of the analysis 
					 or the date the data was encoded into the file.
5	WPCT_O		 Weight percent oxygen.
6	WPCT_S		 Weight percent sulfur.
7	ASH_WPCT 	 Weight percent ash.

The table FRAC_2930_PGS is a combination of two PGS tables and includes data on the fractional composition of rock extracts or oils.

Table FRAC_2930_PGS column definitions (Record Count: 1,534)
		
#	Field Name     	Data Type	 	Field Length (Characters)       
1	WMO		    	Text				20
2	RC_R029		Text				7
3	LC_R029		Text				4
4	DO_R029		Text				6
5	GM_RK_WT		Number (Double)		8
6	PPM_BIT		Number (Double)		8
7	RC_030			Text				7
8	LC_R030		Text				4
9	DO_R030		Text				6
10	PCT_SATS		Number (Double)		8
11	PCT_AROM		Number (Double)		8
12	PCT_N_HC		Number (Double)		8
13	PCT_RECV		Number (Double)		8

Description of the elements:

1	WMO   			Modified form of the API number.
2	RC_029			The old PGS record code for this analysis.
3   LC_R029  	A code depicting the subcontracting laboratory in which the sample was analyzed.
4	DO_R029  		Assumed to be the date of completion of the  
	analysis or the date the data was encoded into the file.
5	GM_RK_WT 		Weight in grams of rock.
6	PPM_BIT  		Parts per million (ppm) of bitumen.
7	RC_030			The old PGS record code for this analysis.
8	LC_R030 	A code depicting the subcontracting laboratory in which the sample was analyzed.
9	DO_R030 		Assumed to be the date of completion of the 
analysis or the date the data was encoded into the file.
10	PCT_SATS  	Percentage of saturated components in the sample.
11	PCT_AROM  		Percentage of aromatic components in the sample.
12	PCT_N_HC    	Percentage of non-hydrocarbon components in the 
					sample.
13	PCT_RECV   		Percent of sample recovered.

The CANGAS_8081_PGS table is again a combination of two PGS tables. This table contains chemical composition data as well as stable carbon isotopic data for the methane and CO2 compounds in the headspace part of canned samples.	

Table CANGAS_8081_PGS column definitions (Record Count: 75)
				
#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO		    	Text				20
2	RC_G080		Text				7
3	LC_G080		Text				4
4	DO_G080		Text				6
5	AIR		    	Number (Double)		8
6	METHANE		Number (Double)		8
7	CO2		    	Number (Double)		8
8	ETHANE			Number (Double)		8
9	H2S		    	Number (Double)		8
10	PROPANE		Number (Double)		8
11	IBUTANE		Number (Double)		8
12	NBUTANE		Number (Double)		8
13	IPENTANE		Number (Double)		8
14	NPENTANE		Number (Double)		8
15	HEXANES		Number (Double)		8
16	RC_G081		Text				7
17	LC_G081		Text				4
18	DO_R081		Text				6
19	13C_C1			Text				8
20	13C_CO2		Text				8
21	COMMENT		Text				40

Description of the elements:

1	WMO   		Modified form of the API number.
2	RC_G080  	The old PGS record code for this analysis.
3	LC_G080  	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_G080  	Assumed to be the date of completion of the analysis 
				or the date the data was encoded into the file.
5	AIR	Mole percentage of both air and nitrogen in the                   sample. 
6	METHANE  	Mole percentage of methane in the sample.
7	CO2	  	Mole Percentage of carbon dioxide in the sample.
8	ETHANE   	Mole Percentage of ethane in the sample.
9	H2S     	Mole Percentage of hydrogen sulfide in the sample.
10	PROPANE  	Mole Percentage of propane in the sample.
11	IBUTANE  	Mole Percentage of iso-butane in the sample.
12	NBUTANE  	Mole Percentage of normal butane in the sample.
13	IPENTANE 	Mole Percentage of iso-pentane in the sample.
14	NPENTANE 	Mole Percentage of normal pentane in the sample.
15	HEXANES  	Estimated mole percentage of hexanes+ in the sample.
16	RC_G081  	The old record code from PGS for this analysis.
17	LC_G081  	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
18	DO_R081  	Assumed to be the date of completion of analysis or 
					the date the data was encoded into the file.
19	13C_C1   	Stable carbon 13C isotope of the methane homolog as 
					compared to the international standard, PDB.
20	13C_CO2  	Stable carbon 13C isotope of the carbon dioxide peak 
					as compared to the international standard, PDB.
21	COMMENT  	Analytical comments regarding the sample. NOTE:  
this comment field is not the same as the comment field in the COMMENTS_PGS or MASTER_PGS tables.

The GASRNG_23_PGS table summarizes the content of most of the more commonly found peaks in the C5-C8 chromatogram.

Table GASRNG_23_PGS column definitions (Record Count: 1,296)
			
#	Field Name     	Data Type	 	Field Length (Characters)        
1	WMO		    	Text				20
2	RC_023			Text				7
3	LC_RO23		Text				4
4	DO_R023		Text				6
5	IC4		    	Number (Double)		8
6	NC4		    	Number (Double)		8
7	NEO_C5			Number (Double)		8
8	IC5		    	Number (Double)		8
9	NC5		    	Number (Double)		8
10	22DM_C4		Number (Double)		8
11	CYC_C5	    		Number (Double)		8
12	23DM_C4		Number (Double)		8
13	2M_C5		    	Number (Double)		8
14	3M_C5		    	Number (Double)		8
15	N_HEX		    	Number (Double)		8
16	M_CYC_C5		Number (Double)		8
17	22_DM_C5		Number (Double)		8
18	BENZENE		Number (Double)		8
19	24_DM_C5		Number (Double)		8
20	223_TMC4		Number (Double)		8
21	CYC_HEX		Number (Double)		8
22	33_DM_C5		Number (Double)		8
23	11DMCYC5		Number (Double)		8
24	2_M_HEX		Number (Double)		8
25	23_DM_C5		Number (Double)		8
26	1C3DMCC5		Number (Double)		8
27	3_M_HEX		Number (Double)		8
28	1T3DMCC5		Number (Double)		8
29	1T2DMCC5		Number (Double)		8
30	3_ETH_C5		Number (Double)		8
31	224TM_C5		Number (Double)		8
32	N_HEP		    	Number (Double)		8
33	1C2DMCC5		Number (Double)		8
34	M_CYC_C6		Number (Double)		8
35	113TMCC5		Number (Double)		8
36	22DM_C6		Number (Double)		8
37	E_CYC_C5		Number (Double)		8
38	TOLUENE		Number (Double)		8
39	C4_C8PPM		Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_023		The old PGS record code for this analysis.
3	LC_RO23	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_R023	Assumed to be the date of completion of the analysis 
					or the date the data was encoded into the file.
5	IC4		Weight percent iso-butane.
6	NC4		Weight percent normal butane.
7	NEO_C5		Weight percent neo-pentane.
8	IC5		Weight percent iso-pentane.
9	NC5		Weight percent normal pentane.
10	22DM_C4	Weight percent 2,2, dimethyl butane.
11	CYC_C5		Weight percent cyclo pentane.
12	23DM_C4	Weight percent 2,3, dimethyl butane.
13	2M_C5		Weight percent 2 methyl pentane.
14	3M_C5		Weight percent 3 methyl Pentane.
15	N_HEX		Weight percent normal hexane.
16	M_CYC_C5	Weight percent methyl cyclo pentane.
17	22_DM_C5	Weight percent 2,2, dimethyl pentane.
18	BENZENE	Weight percent benzene.
19	24_DM_C5	Weight percent 2,4, dimethyl pentane.
20	223_TMC4	Weight percent 2,2,3 tri methyl butane.
21	CYC_HEX	Weight percent cyclo hexane.
22	33_DM_C5	Weight percent 3,3 dimethyl pentane.
23	11DMCYC5	Weight percent 1,1 dimethyl cyclo pentane.
24	2_M_HEX	Weight percent 2 methyl hexane.
25	23_DM_C5	Weight percent 2,3 dimethyl pentane.
26	1C3DMCC5	Weight percent 1-cis-3 dimethyl cyclo pentane.
27	3_M_HEX	Weight percent 3 methyl hexane.
28	1T3DMCC5	Weight percent 1-trans-3 dimethyl cyclo pentane.
29	1T2DMCC5	Weight percent 1-trans-2 dimethyl cyclo pentane.
30	3_ETH_C5	Weight percent 3 ethyl pentane.
31	224TM_C5	Weight percent 2,2,4 trimethyl pentane.
32	N_HEP		Weight percent normal heptane.
33	1C2DMCC5	Weight percent 1-cis-2 dimethyl cyclo pentane.
34	M_CYC_C6	Weight percent methyl cyclo hexane.
35	113TMCC5	Weight percent 1,1,3 trimethyl cyclo pentane.
36	22DM_C6	Weight percent 2,2, dimethyl hexane.
37	E_CYC_C5	Weight percent ethyl cyclo pentane.
38	TOLUENE	Weight percent toluene.
39	C4_C8PPM	Parts Per Million (ppm) all C4-C8 compounds.

The GC_3162_PGS table contains information on the C7-C35 normal alkanes within the saturate fraction of the sample.

Table GC_3162_PGS column definitions (Record Count: 1,061)
					
#	Field Name     	Data Type	 	Field Length         	
1	WMO			Text				20
2	RC_031			Text				7
3	LC_031			Text				4
4	DO_031			Text				6
5	N_C7			Number (Double)		8
6	N_C8			Number (Double)		8
7	N_C9			Number (Double)		8
8	N_C10			Number (Double)		8
9	N_C11			Number (Double)		8
10	N_C12			Number (Double)		8
11	N_C13			Number (Double)		8
12	N_C14			Number (Double)		8
13	N_C15			Number (Double)		8
14	N_C16			Number (Double)		8
15	N_C17			Number (Double)		8
16	PRIST			Number (Double)		8
17	N_C18			Number (Double)		8
18	PHYT			Number (Double)		8
19	N_C19			Number (Double)		8
20	N_C20			Number (Double)		8
21	N_C21			Number (Double)		8
22	N_C22			Number (Double)		8
23	N_C23			Number (Double)		8
24	N_C24			Number (Double)		8
25	N_C25			Number (Double)		8
26	N_C26			Number (Double)		8
27	N_C27			Number (Double)		8
28	N_C28			Number (Double)		8
29	N_C29			Number (Double)		8
30	N_C30			Number (Double)		8
31	N_C31			Number (Double)		8
32	N_C32			Number (Double)		8
33	N_C33			Number (Double)		8
34	N_C34			Number (Double)		8
35	N_C35			Number (Double)		8
36	PCT_RESL		Number (Double)		8
37	CPI			Number (Double)		8
38	PR_PH			Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_031		The old PGS record code for this analysis.
3	LC_031	A code depicting the subcontracting laboratory in  which the sample was analyzed. 
4	DO_031	Assumed to be the date of completion of the analysis or the date the data was encoded into the file.
5	N_C7		Weight percent normal C7.
6	N_C8		Weight percent normal C8.
7	N_C9		Weight percent normal C9.
8	N_C10		Weight percent normal C10.
9	N_C11		Weight percent normal C11.
10	N_C12		Weight percent normal C12.
11	N_C13		Weight percent normal C13.
12	N_C14		Weight percent normal C14.
13	N_C15		Weight percent normal C15.
14	N_C16		Weight percent normal C16.
15	N_C17		Weight percent normal C17.
16	PRIST		Weight percent pristine.
17	N_C18		Weight percent normal C18.
18	PHYT		Weight percent phytane.
19	N_C19		Weight percent normal C19.
20	N_C20		Weight percent normal C20.
21	N_C21		Weight percent normal C21.
22	N_C22		Weight percent normal C22.
23	N_C23		Weight percent normal C23.
24	N_C24		Weight percent normal C24.
25	N_C25		Weight percent normal C25.
26	N_C26		Weight percent normal C26.
27	N_C27		Weight percent normal C27.
28	N_C28		Weight percent normal C28.
29	N_C29		Weight percent normal C29.
30	N_C30		Weight percent normal C30.
31	N_C31		Weight percent normal C31
32	N_C32		Weight percent normal C32.
33	N_C33		Weight percent normal C33.
34	N_C34		Weight percent normal C34.
35	N_C35		Weight percent normal C35.
36	PCT_RESL	Percent resolved peaks.
37	CPI		Carbon preference index.
38	PR_PH		Ratio pristane/phytane.

The ISOT_38_PGS table contains information on the asphaltene fraction of the sample.

Table ISOT_38_PGS column definitions (Record Count: 103)
 		
#	Field Name     	Data Type	 	Field Length (Characters)      
1	WMO			Text				20
2	RC_O038		Text				7
3	LC_O038		Text				4
4	DO_O038		Text				6
5	WPCT_S			Number (Double)		8
6	34S_ASPH		Text				8
7	WPCT_N			Number (Double)		8
8	15N_ASPH		Text				8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_O038	The old PGS record code for this analysis.
3	LC_O038	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_O038	Assumed to be the date of completion of the 
					analysis or the date the data was encoded into the file.
5	WPCT_S	 	Weight percent sulfur.
6	34S_ASPH	 34S of asphaltenes.
7	WPCT_N		Weight percent nitrogen.
8	15N_ASPH	 15N of asphaltenes.

The LEGEND_PGS table is a tool to document the original table names and contents into the present day scheme.

Table LEGEND_PGS column definitions (Record Count: 24)
		
#	Field Name     	Data Type	 	Field Length (Characters)        
1	TABN			Text				8
2	NUMCOLS		Number (Double)		8
3	NUMROWS		Number (Double)		8
4	ORIGPGS1		Text				8
5	ORIGPGS2		Text				8
6	ORIGPGS3		Text				8
7	ORIGPGS4		Text				8
8	COMMENT		Text				40

Description of the elements:

1	TABN		Table ID.
2	NUMCOLS	Number of columns.
3	NUMROWS	Number of rows.
4	ORIGPGS1	Original PGS table ID of 1st table.
5	ORIGPGS2	Original PGS ID of 2nd table.
6	ORIGPGS3	Original PGS ID of 3rd Table.
7	ORIGPGS4	Original PGS ID of 4th Table.
8	COMMENT	Comments on naming convention.

The RKEV_41_PGS table contains information on Rock-Eval (pyrolysis) samples.

Table RKEV_41_PGS column definitions (Record Count: 7,534)

#	Field Name     	Data Type	 	Field Length (Characters)        	
1	WMO			Text				20
2	RC_R041		Text				8
3	LC_R041 		Text				8
4	DO_R041		Text				8
5	TMAX			Number (Double)		8
6	S1				Number (Double)		8
7	S2				Number (Double)		8
8	S3				Number (Double)		8
9	PI				Number (Double)		8
10	S2S3			Number (Double)		8
11	PC				Number (Double)		8
12	OC				Number (Double)		8
13	HI				Number (Double)		8
14	OI				Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_R041	The old PGS record code for this analysis.
3	LC_R041	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_R041	Assumed to be the date of completion of the analysis or 
					the date the data was encoded into the file.
5	TMAX		Tmax (maximum temperature) of S2 peak (°C)
6	S1			Amount of volatile hydrocarbons(hc) (S1, milligrams rock) 
					(hc/gram rock).
7	S2			Amount of pyrolyzable hydrocarbons # (hc) (S2, milligrams 
					rock) (hg/gram rock).
8	S3			Amount of CO2 released during pyrolysis (milligrams CO2 / 
					gram rock).
9	PI			Rock-Eval Production Index (S1/S1+S2).
10	S2S3		S2/S3 Ratio of pyrolyzable hydrocarbons to CO2.
11	PC			Total pyrolyzable organic carbon (in weight percent of 
					rock).
12	TOC		Total organic Carbon (in weight percent of rock).
13	HI			Rock-Eval Hydrogen Index (mg hc/gram organic carbon).
14	OI			Rock-Eval Oxygen Index (mg CO2 /gram organic carbon).

The SPGR_60_PGS table contains information on the Specific Gravity of crude oils.

Table SPGR_60_PGS column definitions (Record Count: 84)
 	 		
#	Field Name     	Data Type	 	Field Length         
1	WMO	Text				20
2	RC_O060		Text				7
3	LC_O060		Text				4
4	DO_O060		Text				6
5	SPGR			Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_O060	The old PGS record code for this analysis.
3	LC_O060	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_O060	Assumed to be the date of completion of the analysis or 
					the date the data was encoded into the file.
5	SPGR		API gravity (crude oils only).

The TAI_35_PGS table contains information on the Thermal Alteration Index of the sample.

Table TAI_35_PGS column definitions (Record Count: 3,846)
 	
#	Field Name     	Data Type	 	Field Length         	
1	WMO			Text				20
2	RC_R035		Text				7
3	LC_R035		Text				4
4	DO_R035		Text				6
5	TAI			Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_R035	The old PGS record code for this analysis.
3	LC_R035	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_R035	Assumed to be the date of completion of the analysis or the 
				date the data was encoded into the file.
5	TAI		Thermal Alteration Index.

The TC_TOC_2728_PGS combined table contains information on the total carbon and total organic carbon concentrations of rock samples.

Table TC_TOC_2728_PGS column definitions (Record Count: 18,493)
		
#	Field Name     	Data Type	 	Field Length (Characters)       
1	WMO			Text				20
2	RC_R027		Text				4
3	LC_R027		Text				4
4	DO_R027		Text				6
5	TOC_WTPC		Number (Double)		8
6	LC_R028		Text				4
7	DO_R028		Text				6
8	TC_WTPCT		Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_R027	The old PGS record code for this analysis.
3	LC_R027	A code depicting the subcontracting laboratory in
					which the sample was analyzed.  
4	DO_R027	Assumed to be the date of completion of the analysis or the 
					date the data was encoded into the file.
5	TOC_WTPC	Weight percent total organic carbon.
6	LC_R028	A code depicting the subcontracting laboratory in
					which the sample was analyzed.
7	DO_R028	Assumed to be the date of completion of the analysis or the 
					date the data was encoded into the file.
8	TC_WTPCT	Weight percent total carbon.

The TEAFID_26_PGS table contains information on the pyrolysis of rock samples via thermal evolution analysis (TEA). 
 
Table TEAFID_26_PGS column definitions (Record Count: 6338)
		
#	Field Name     	Data Type	 	Field Length         
1	WMO		 	Text				20
2	RC_R026	 	Text				7
3	LC_R026	 	Text				4
4	DO_R026	 	Text				6
5	HC_YIELD	 	Number (Double)		8
6	VOLATILE	 	Number (Double)		8
7	TEA_MAX	 	Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_R026	The old PGS record code for this analysis.
3	LC_R026	A code depicting the subcontracting laboratory in
					which the sample was analyzed.
4	DO_R026	Assumed to be the date of completion of the analysis or the 
					date the data was encoded into the file.
5	HC_YIELD	Weight PCT hydrocarbon yield.
6	VOLATILE	Parts per million volatile Hydrocarbons <300o C.
7	TEA_MAX	Maximum temp of Hydrocarbon yield by TEA.

The VISKER_34_PGS table contains information on the visual kerogen types.

Table VISKER_34_PGS column definitions (Record Count: 4,538)
	
#	Field Name     	Data Type	 	Field Length         
1	WMO			Text				20
2	RC_R034		Text				7
3	LC_R034		Text				4
4	DO_R034		Text				6
5	AMORP			Number (Double)		8
6	HERBA			Number (Double)		8
7	WOODY			Number (Double)		8
8	INERT			Number (Double)		8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_R034	The old PGS record code for this analysis.
3	LC_R034	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_R034	Assumed to be the date of completion of the analysis or the 
					date the data was encoded into the file.
5	AMORP		Normalized percent amorphous kerogen.
6	HERBA		Normalized percent herbaceous kerogen.
7	WOODY		Normalized percent woody kerogen.
8	INERT		Normalized percent inert kerogen.

The VITREF_33_PGS table contains information on the vitrinite reflectance of samples.

Table VITREF_33_PGS column definitions (Record Count: 4,830)
 	 	
#	Field Name     	Data Type	 	Field Length         
1	WMO	 		Text				20
2	RC_R033	 	Text				7
3	LC_R033	 	Text				4
4	DO_R033	 	Text				6
5	P_QUAL	 		Text				8
6	EASE_CY1	 	Text				8
7	RO_MEAN	 	Number (Double)		8
8	MODAL	 		Number (Double)		8
9	PYRITE	 		Text				8
10	ROS			Text				8

Description of the elements:

1	WMO		Modified form of the API number.
2	RC_R033	The old PGS record code for this analysis.
3	LC_R033	A code depicting the subcontracting laboratory in 
					which the sample was analyzed.
4	DO_R033	Assumed to be the date of completion of the analysis or the 
					date the data was encoded into the file.
5	P_QUAL		Quality of the polish.
6	EASE_CY1	Ease of selecting the first cycle.
7	RO_MEAN	Mean value of all reflectance measurements.
8	MODAL		Median reflectance value
9	PYRITE		Abundance of pyrite.
10	ROS		Individual reflectance measurements.

Other tables in the Alaskan database are designed to be used as reference tables or lookup tables.  These tables are included but are not intended to be used as stand-alone data tables (see LEGEND_PGS table for explanations.)

The R_UNIT_PGS table contains data that is included in the HEADER_PGS table.  This table is useful to obtain English conversion of the many rock unit codes used in the Header_PGS table.

Table R_UNIT_PGS column definitions (Record Count: 742)

#	Field Name     	Data Type	 	Field Length         	
1	FAGE			Text				4
2	FUNIT			Text				4
3	FM				Text				43
4	ERA			Text				40

Description of the elements:

1	FAGE		Formation age code.
2	FUNIT		Formation unit code.
3	FM			English formation name.
4	ERA		Major geologic Era.

The POINTS_PGS table contains outcrop location information included in the HEADER_PGS table.

Table POINTS_PGS column definitions (Record Count: 2,933)
	
#	Field Name     	Data Type	 	Field Length         	
1	WMO			Text				19
2	ID				Text				20
3	UNKN1			Text				20
4	LATTIT			Number (Double)		8
5	LO				Number (Double)		8
6	ELE			Text				10
7	FAGE			Text				4
8	FUNIT			Text				4

Description of the elements:

1	WMO		Modified form of the API number.
2	ID			Sample identification.
3	UNKN1		unknown field. 
4	LATTIT		Latitude.
5	LO			Longitude.
6	ELE		Elevation.
7	FAGE		Formation age code.
8	FUNIT		Formation unit code.

The MASTER_PGS table contains information on the correlation between WMO numbers and their associated records. It also includes the comment field from COMMENTS_PGS.

Table MASTER_PGS column definitions (Record Count: 131,459)
		
#	Field Name     	Data Type	 	Field Length         	
1	WMO			Text				20
2	CODES			Text				7
3	COMMENT		TEXT 				40

Description of the elements:

1	WMO		Modified form of the API number.
2	CODES		Record codes.
3	COMMENT 	Analytical comments regarding the analysis from the 
					contracting lab.

The A001_Wells_PGS table contains information on the wells sampled. This information is contained in the Header_PGS table.

Table A001_WELLS_PGS column definitions (Record Count: 19,103)
			
#	Field Name     	Data Type	 	Field Length         	
1	WMO			Text				20
2	API			Text				14
3	X					Text				4
4	RC_A001		Text				7
5	WELLN			Text				40
6	ELEV			Text				10
7	TLD			Text				7
8	WELCLAS		Text				2
9	SRT			Text				10
10	FD_A001		Text				6

Description of the elements:

1	WMO		Modified form of the API number.
2	API		Unique American Petroleum Institute well number.
3	X				Unknown field.
4	RC_A001	The old PGS record code for this analysis.
5	WELLN		Well name.
6	ELEV		Elevation.
7	TLD		Total depth.
8	WELCLAS	Well class.
9	SRT		Location of Well in DTTTDRRRSS notation.
10	FD_A001	File date.

The B001_Outcrops_PGS table contains data on the outcrops sampled in the study.  This information resides in the Header_PGS table.

Table B001_OUTCROPS_PGS column definitions (Record Count: 21,941)

#	Field Name     	Data Type	 	Field Length         	
1	WMO			Text				20
2	API			Text				14
3	SQ				Text				4
4	RC_B001		Text				7
5	LC_B001		Text				4
6	LABNO			Text				8
7	DI_B001		Text				6
8	M1				Text				1
9	TOP			Number (Double) 		8
10	BOT			Number (Double)		8
11	STY			Text			 	2
12	ADDNL			Text				17
13	FD_B001		Text				6

Description of the elements:

1	WMO		Modified form of the API number.
2	API		Unique American Petroleum Institute well number.
3	SQ			Sequence number.
4	RC_B001	The old PGS record code for this analysis.
5	LC_B001	A code depicting the subcontracting laboratory in
					which the sample was analyzed.
6	LABNO		Laboratory ID number.
7	DI_B001	Date sample entered into laboratory.
8	M1			Measurement in (F)eet or (M)eters.
9	TOP		Top depth.
10	BOT		Bottom depth.
11	STY		Sample type.
12	ADDNL		Additional comments.
13	FD_B001	File date.

						Index and Encoding Schemes

ADDNL			Submitter's Additional Description (free format ASCII)

API		 		Modified American Petroleum Institute number (assigned for
all samples from within the United States and the U.S. Exclusive Economic Zone [USA/EEZ]);  or see WMO.

BD				Bottom Depth sampled in units specified by M1
				(8 bytes, integer or floating point number).

CONTAINER   A code formed by the concatenation of the container type (CT),
				1 character + the external condition of the container (EC), 2
				characters + the internal condition of the container (IC), 1
				character + any additional information on the sample within
				the container (AD) 2 characters. Below is a breakout of these 
				fields:
		
	CT	container type code (1 byte maximum):
		Code:	Container type:
			B		Pressure cylinder (bomb)
			C		Can
			E		Paper or plastic envelope or bag
			G		Glass bottle
			P		Plastic bottle
			U		None (or unknown)

	EC		Container external condition code (2 bytes maximum):
		Code:	External condition:
			AT		Tightly sealed, no holes or tears (air-tight)
			NT		Not tightly sealed, damaged
			UK		Unknown

	IC		Container internal condition code (1 bytes maximum)
		Code:	Internal condition:
		-0-		(null) not applicable
			A		Sample absent
			D		Dry
			M		Wet
			U		Unwashed
			Q		Unknown

	AD		Known additional information on the sample within the container. A 2-byte (maximum) code is used here to describe the following: 
		Code:	Additional information:

			CL		Control sample
			CO		Coal
			CS		Composite
			DT		Drill stem test
			OS		Oil-stained rock
			UK		Unknown
			RS	Research sample (not applicable directly to mapping)

CONTAM		(Possible or probable) Contaminant codes, usually provided by submitter or sample prep lab technician. Modeled after PI PGS "Catalog of contaminants" 6 byte code, first 3 bytes = contaminant code, last 3 bytes = % abundance 
		Code:	Contaminant:

		-0-		(null) = no observable contaminants (default)
		B01		Unknown contaminant
		B02		Varied organic contaminants
		B03		Varied inorganic contaminants
		B04		Carvings (from borehole)
		B05		Casing cement
		B06		Drilling mud
		B07		Mud additives
		B08		Walnut shells
		B09		Straw
		B10		Mica
		B11		Rubber
		B12		Oil base drilling mud
		B13		Pipe dope
		B14		Gilsonite
		B15		Asphalt
		B19		No contaminants
		B21		Diesel oil
		B22		Crude oil
		B23		Lignosulfonate
		B25		Sample package contaminant (core box wax)
% Abundance = 000 through 100%; 001 implies 1% or less estimated abundance of suspect contaminant; default 000 implies no contaminants or not applicable.

ELEV		Elevation of well or surface sample in units
			specified by M1 (8 bytes, integer or floating-point number).

FAGE		Formation age code (3 decimal digits):
The FAGE and FUNIT codes are the concept of Petroleum Information Corp. (PI) and the FAGE code is a combination of two fields: the first two digits for encoding the geologic time table SYSTEM, and the last digit for encoding the geologic time table EPOCH or (series). Please note that the Fage and Funit elements do not necessarily conform to accepted USGS naming conventions or standards in appropriate naming of lithological sections.

		Code, SYSTEM:			Code, Series:

		00 Unknown				0 Unknown

		70 Quaternary			9 Undifferentiated
								2 Holocene
								1 Pleistocene
		66 Quaternary			9 -Tertiary (boundary)
		65 Tertiary			9 Undifferentiated
								5 Pliocene
								4 Miocene
								3 Oligocene
								2 Eocene
								1 Paleocene
		61 Tertiary			9 Cretaceous (boundary)
 		60 Cretaceous			9 Undifferentiated
								5 Gulfian
								4 Montanan
								3 Coloradoan
								2 Comanchean
								1 Coahuilan
		56 Jurassic			9 -Cretaceous (boundary)
 		55 Jurassic			9 Undifferentiated
								3 Upper
								2 Middle
								1 Lower
 		51 Triassic			9 -Jurassic (boundary)
 		50 Triassic			9 Undifferentiated
								3 Upper
								2 Middle
								1 Lower
	 	46 Permo				9 -Triassic (boundary)
 		45 Permian				9 Undifferentiated
 								4 Ochoan
								3 Guadalupian
								2 Leonardian
								1 Wolfcampian
 		41 Permo				9 -Pennsylvanian (boundary)
	 	40 Pennsylvanian			9 Undifferentiated
								6 Virgilian or Cisco or Monogahelan
								5 Missourian or Canyon or Conemaughan
								4 Desmoinesian or Strawn or Alleghenian
								3 Atokan or Bend or Pottsvillian
								2 Morrowan
								1 Springeran
 		36 Mississippian			9 -Pennsylvanian (boundary)
 		35 Mississippian			9 Undifferentiated
								4 Chesterian
								3 Meramecian
								2 Osagean
								1 Kinderhookian
	 31 Mississippian			9 -Devonian (boundary)
	 30 Devonian			9 Undifferentiated
								6 Upper
								5 Bradfordian
								4 Chautauquan
								3 Senecan
								2 Erian or Middle
								1 Ulsterian or Lower
 		26 Silurian			9 -Devonian (boundary)

 		25 Silurian			9 Undifferentiated
								3 Cayugan
								2 Niagaran
								1 Albion or Alexandrian
 		21 Silurian			9 -Ordovician (boundary)
 		20 Ordovician			9 Undifferentiated
								3 Cincinnatian
								2 Champlainian
								1 Canadian
 		16 Cambro				9 -Ordovician (boundary)
	 	15 Cambrian	9 Undifferentiated
								3 Croixian
								2 Albertan
								1 Waucoban
 		11 Precambrian			9 -Cambrian (boundary)
 		10 Precambrian			9 Undifferentiated

FUNIT	Formation name code (as many as 5 bytes, alphabetic)
The FUNIT code is an abbreviation of localized naming of the sample collection zone. The codes are 4 - 5 characters in length and for this data set can be found in the table entitled: R_unit_PGS. See comments on FAGE above.

HCST		Side-track/hole-change part of API number.
			(4 numeric digits)

LAT		Sampling location latitude (a +/- real value to 5 decimal places).

LC_* A code depicting the subcontracting laboratory in which the sample was analyzed. The first 2 alpha characters of the 4 character code is the contractor code (CC):

	AK		Alaska Div of Oil & Gas
	CL		Core Labs, Inc.
	CS		Canadian Geological Survey
	GC		Geochem Research
	GS		USGS Organic Geochem Lab, Denver, CO
	MO		Mobil Oil Co.
	NA		Not Available/unknown
	SH		Shell Oil Co.
	TE		Tenneco Oil Co.
	UN		Unical Oil Co.
	WH		Woods Hole

The next two characters in the LC_* codes are the laboratory codes for the analytical lab performing the analyses (LC):

	BR		Brown & Ruth Labs
	CL		Core Labs, Inc.
	CS		Canadian Geological Survey
	GC		Geochem Research
	GG		Global Geochemistry Corp.
	GS		USGS Organic Geochem Lab, Denver, CO
	NA		Not Available/unknown
	SH		Shell Oil Co.
	TE		Tenneco Oil Co.
	UN		Union Oil Co.
	WH		Woods Hole

LITHO		Lithology codes as many as 4 alphabetic characters for the
actual lithology, then 3 decimal digits expressing the approximate percentage of the lithology, as determined by the submitter or laboratory technician. (The sum of all LITHO and CONTAM percentages should be 100.)

		Code:	Lithology:

		XXXX		Not available or not determined
		ANHY		Anhydrite
		CCRN		Concretion
		CHRT		Chert
		COAL		Coal
		DOLL		Limey dolomite
		DOLO		Dolomite
		FLMD		Mudstone
		FLSH		Shale
		FMCY		Claystone
		LSAR		Argillaceous limestone
		LSCH		Cherty limestone
		LSDL		Limey dolomite
		LSFL		Laminated limestone
		LSND		Limestone
		MICR		Micrite
		SALT		Salt
		SHBT		Bituminous shale
		SILT		Siltstone
		SSBT		Tar or solid bitumens
		SSLS		Limey sandstone
		SSND		Sandstone
		TUFF		Volcanic tuff

LONG		Sampling location longitude (a +/- real value to 5 decimal places)

M1		English or Metric units indicator (one character, either
		F for depths and elevations in feet, or
		M for depths and elevations in meters).

POR		Porosity code (one numeric digit), supplied by the submitter; estimated (not measured, see below).

		Code:	Porosity:

			0		Unknown (default)
			1		Tight
			2		Very poor
			3		Poor
			4		Fair
			5		Good
			6		Excellent

SQ		(as many as 4 ASCII characters, but usually integer numbers)
The last 4 digits of the WMO number designed to provide unique WMO numbers for down-hole samples. 

SHO 	Included for compatibility with PI PGS (Oil) "SHOW" code supplied by the submitter. This element contains one numeric digit.

		Code:	Quality of oil show:

			0		Unknown (default)
			1		No show
			2		Very poor
			3		Poor
			4		Fair
			5		Good
			6		Excellent

SRT		For samples within US/EEZ, by Township, Range and Section:
		(10 alphanumeric characters)

	Character
	Position:		Definition:

		1				Township direction (N or S)
		2-4			Township number (right justified, leading blanks)
		5				Range direction (E or W)
		6-8			Range number (right justified, leading blanks)
		9-10			Section number (right justified, leading blanks)

STY		Sample source code, 2 alpha characters:

		Code:	Sample source:

		CO		Core
		CT		Cuttings
		EN		Emulsion
		GC		Suspected contaminant
		GS		Natural gas
		IG		Inorganic
		LO		Generic liquid
		MD		Drilling mud
		OL		Crude oil or natural gas condensates
		OT		Outcrop
		SO		Generic solid
		SW		Side wall core
		UK		Unknown
		WT		Water

SW		Sample weight in grams (0 to 9999, right justified)

TD		Top Depth sampled in units specified by M1
		(8 bytes, integer or floating-point number)

TLD		Total depth of well in units specified by M1
		(8 bytes, integer or floating-point number)

UNIQ		Unique well code part of API (digits 6-11 of the API
			number);  compare with API encoding scheme.

WMO 		A modified World Meteorological Organization number (assigned for all samples outside the USA/EEZ. The total number of digits in the modified API (or WMO) number is 19, defined thus:

 1  		World code based on 4 quadrants relative to the
  			Equator and the Greenwich Meridian:

			Digit
			Position:	Definition:

		1 			= northeast quadrant
		3 			= southeast quadrant
		5 			= southwest quadrant
		7 			= northwest quadrant
		9 			= USA/EEZ

 2-3		Two-digit State or latitude code:
			(a) State code as defined by API for USA/EEZ (World = 9)
			(b) Latitude of location truncated to the nearest degree
		    	(World = 1, 3, 5, or 7)

 4-6		Three-digit county or longitude code:
			(a) County code as defined by API for USA/EEZ (World = 9)
			(b) Longitude of location truncated to the nearest degree
		    	(World = 1, 3, 5, or 7)

 7-11		Five-digit unique well code:
			(a) 0000-64999 assigned by API for USA/EEZ (World = 9)
			(b) 10000-94999 assigned by USGS WAPI for wells outside
		    	the USA/EEZ (World = 1, 3, 5, or 7)
			(c) 65000-94999 used for wells for which API has
		    	not assigned a number (World = 9) assigned by USGS WAPI
			(d) 95000-99999 assigned by USGS WAPI for non-
					well samples (surface, outcrops, speleological,
		    	mines, seeps, etc.)(World = 1, 3, 5, 7, or 9)

12-13		Two-digit side track code assigned by API (World = 9)

14-15		Two-digit hole change code assigned by API (World = 9)

16-19		Four-digit sample sequence number assigned by USGS WAPI

Note: digits 2-15 of the USGS WMO number are identical to the fourteen-digit unique API number for all wells within USA/EEZ 
(World = 9). The expanded API/WMO number was developed to assign unique numbers to specific samples collected worldwide.

WSC		World/State/County or World/Lat/Long part of API (digits
		1-6 of the API number);  compare with API encoding scheme.

Appendix A

Definitions of Some Commonly Used Terms

ASCII--American Standard Code for Information Interchange; usually refers to the characters, numbers, and punctuation marks found on a typewriter or computer keyboard.

CHROMATOGRAPHY--A method of separating complex mixtures into
individual chemical compounds or classes of chemical compounds by differences in their chemical behavior.

EXTRACTION--The process of dissolution of particular chemical
		compounds from a solid matrix (that is, rock) into a liquid solution (that is, bitumen or rock extract).

FRACTION--A group of chemical compounds with similar chemical and
		physical properties (i.e., saturated hydrocarbons, aromatic hydrocarbons, resins, asphaltenes, kerogen).

GLOBAL--Applicable to all users.

LOCAL	--Applicable to a small group of users (not global).

PYROLYSIS--The heating of a sample in the absence of air;
		followed by subsequent analysis of the products obtained in order to determine quantities of products and/or reaction kinetic factors. Hydrous pyrolysis is done in the presence of an overabundance of water; anhydrous pyrolysis is done on the dry sample.

ROCK-EVAL--A rapid anhydrous pyrolysis technique used to semi-
		quantitatively determine the type and quantity of petroleum that could be generated from an oil or gas source rock. A less rapid Rock-Eval technique can also determine kinetic factors.

VITRINITE--A maceral derived from wood or coaly material that
		exhibits higher optical reflectivity with increasing exposure to higher temperatures; a thermal maturity indicator.

Appendix B

Manufacturers of Products and Services Mentioned

American Petroleum Institute
Production Department
211 N. Ervay, suite 1700
Dallas, TX 75201 USA

MicroRim
3925 159th Ave NE
PO Box 97022
Redmond, WA 98073-9722 USA

MicroSoft Corporation
16011 NE 36th Way
PO Box 97017
Redmond, WA 98073-9717 USA

Perkin-Elmer/Nelson Chromatography
10061 Bubb Road
Cupertino, CA 95014 USA

Petroleum Information Corporation
4100 E. Dry Creek Road
Littleton, CO 80122 USA

Rock-Eval pyrolysis instrument
Contact:
Delsi Inc.
600 Kenrick, Suite D-7
Houston, TX 77060 USA

World Meteorological Organization numbering system
Contact:
National Oceanographic Data Center
National Oceanographic and Atmospheric Administration
Washington, DC USA