OCEAN DRILLING PROGRAM revised DATA FILE DOCUMENTATION July 1990 SEDIMENT CHEMICAL ANALYSES ROCK-EVAL I. INTRODUCTION The Rock-Eval data file contains data generated by the Delsi Nermag Rock_Eval II Plus TOC instrument onboard the JOIDES Resolution. The Rock_Eval II Plus TOC is a microprocessor-based instrument for whole rock or sediment pyrolysis, used to evaluate type and maturity of organic carbon, calculate petroleum potential, and detect oil shows. The Rock_Eval instrument is predominantly used on the ship as an interpretive tool for safety hydrocarbon monitoring. This revised edition includes the changes in the field positions caused by deleting the spaces between bottom_interval and weight and S1 through OI. Each record in the data file includes the sample identifier, five basic parameters (S1, S2, S3, temperature max (Tmax), and total organic carbon (TOC)) along with several calculated values (productivity index (PI), petroleum potential or pyrolyzed carbon (PC), hydrogen index (HI), and oxygen index (OI)). Note that the values for PI, S2/S3, and PC are somewhat questionable since the ODP samples are taken from unconsolidated oceanic sediments rather than petroleum source rocks. If you have problems or questions concerning these data, please contact: Data Librarian, Data Base Group Ocean Drilling Program Texas A&M University Research Park 1000 Discovery Drive College Station, Texas 77845-9547 U.S.A. (979) 845-8495, 845-2673 Easylink (Telex) Number: 62760290 Email: database@odpemail.tamu.edu Fax Number: 979-845-4857 II. LEGS IN THE DATA FILE The data file contains data from Legs 101 to 129. No Rock-Eval data were collected on Legs 102, 106, 107, 109, 114, 115, 118, or 121. III. BIBLIOGRAPHY Emeis, K., and Kvenvolden, K.A., 1986. "Shipboard Organic Geochemistry on JOIDES Resolution", Ocean Drilling Program Technical Note No. 7, 130 p. Kvenvolden, K.A., and McDonald, T.J., 1986. "Organic Geochemistry on the JOIDES Resolution--An Assay", Ocean Drilling Program Technical Note No. 6, 147 p. Tissot, B.P., and Welte, D.H., 1984. Petroleum Formation and Occurrence: 2nd Edition, Berlin: Springer-Verlag, 699 p. IV. DATA ITEM FORMATS ROCK-EVAL ITEMS FORMAT ========================= ========= SAMPLE_CODE Text 4 LEG Integer 3 SUBLEG Text 1 SITE Integer 4 HOLE Text 1 CORE Integer 3 CORETYPE Text 1 SECTION Text 2 TOP_INTERVAL Integer 3 BOTTOM_INTERVAL Integer 3 WEIGHT Decimal F5.1* TEMPERATURE_MAX (Tmax) Integer 3 S1 Decimal F5.2** S2 Decimal F5.2** S3 Decimal F5.2** PI (Productivity Index) Decimal F5.2** S2_S3 (S2/S3) Decimal F5.2** PC (Petroleum Potential) Decimal F5.2** TOC (Total Organic Carbon) Decimal F5.2** HI (Hydrogen Index) Decimal F7.2*** OI (Oxygen Index) Decimal F8.2**** COMMENTS Text 50***** NGDC notes: * actual format F6.1 ** actual format F6.2 *** actual format F8.2 **** actual format F9.2 ***** actual format Text 40 V. EXPLANATION OF THE ROCK-EVAL DATA ITEMS SAMPLE_CODE - An alpha code identifying the investigator or test for which the sample was taken. LEG - Number identifying the cruise. The Ocean Drilling Program started numbering the cruises of the JOIDES Resolution at Leg 101. SUBLEG - Letter identifying a subleg or transit. A subleg is the continuation of a Leg after a port call; it often involves a crew change. 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 Sampler 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. WEIGHT - Sample weight in mg. TEMPERATURE_MAX - Tmax. The temperature (in degrees C) at which maximum release of hydrocarbons from cracking of kerogen during pyrolysis occurs (measured at peak of S2). S1 - This peak represents the quantity (in mg hydrocarbon/g rock) of free hydrocarbons (oil and gas) present in the rock and which are volatilized below 300 degrees C. S2 - This peak gives the amount of hydrocarbon-type compounds (in mg hydrocarbon/g rock) produced by the cracking of kerogen as the temperature increases to 600 degrees C. This also shows the quantity of hydrocarbons which could be produced in this rock should burial and maturation continue. S3 - This peak shows the quantity of CO2 (measured in mg CO2/g rock) produced from pyrolysis of the organic matter in the rock up to 390 degrees C. PI - Productivity Index = S1/(S1 + S2). PI characterizes the evolution level of the organic matter. PI typically increases with depth and can be used to pinpoint zones of unusually high or low amounts of hydrocarbons. S2_S3 - Value = S2/S3 which is a means of determining the type of organic matter in the rock. PC - Petroleum Potential or Pyrolyzed Carbon = k(S1 + S2), where k = 0.083 mg carbon/g rock. PC corresponds to the maximum quantity of hydrocarbons capable of being produced from the source rock or sediment given sufficient burial depth and time. TOC - Total Organic Carbon in weight percent. HI - Hydrogen Index = (100 x S2)/TOC. HI indirectly determines the ratio of hydrogen to carbon. It is a parameter used to evaluate the type of organic matter present. OI - Oxygen Index = (100 x S3)/TOC. OI indirectly determines the ratio of oxygen to carbon. It is also used to evalute the type of organic matter present. COMMENTS - Contains any comments or remarks about the sample. RECORD FORMAT ON TAPE FOR THE ROCK-EVAL DATA SET COLUMN FIELD ON FILE ===================== ========= SAMPLE_CODE 2-5 LEG 6-8 SUBLEG 9-9 SITE 10-13 HOLE 14-14 CORE 15-17 CORETYPE 18-18 SECTION 19-20 TOP_INTERVAL 21-23 BOTTOM_INTERVAL 24-26 WEIGHT 27-31 (27-32)* TEMPERATURE_MAX (Tmax) 32-34 (33-35)* S1 35-39 (36-41)* S2 40-44 (42-47)* S3 45-49 (48-53)* PI (Productivity Index) 50-54 (54-59)* S2_S3 (S2/S3) 55-59 (60-65)* PC (Petroleum Potential) 60-64 (66-71)* TOC (Total Organic Carbon) 65-69 (72-77)* HI (Hydrogen Index) 70-76 (78-85)* OI (Oxygen Index) 77-84 (86-94)* COMMENTS 85-134 (95-134)* NGDC note: * actual column positions noted in parentheses