ORGANIC GEOCHEMISTRY IN OIL AND GAS EXPLORATION IN CROATIA
Main researcher
: ALAJBEG, ANĐA (202) Assistants
WILDER, LJERKA (136264)
TODORIĆ, ANTE (169963)
ŠVEL-CEROVEČKI, SVEA (85822)
LEBINEC, IVANKA (169915)
Type of research: applied Duration from: 10/10/91. to 02/24/94. Papers on project (total): 31
Papers on project quoted in Current Contents: 4
Institution name: INA, Razvoj i istraživanje, Zagreb (61) Department/Institute: INA-RESEARCH AND DEVELOPMENT Address: SAVSKA 41/X City: 10000 - Zagreb, Croatia
Communication
Phone: 385 (0)1 216 316
Phone: 385 (0)1 233 16 66/2468
Fax: 385 (0)1 215 273
Phone: 385 (0)1 611 55 11
Summary: Intensive research is undertaken in order to elucidate the
age, origin, type, deposition environment, maturity and alteration of
oils and the related matter in the sedimentation basins in Croatia. For
Drava Depression and Slavonija-Srijem Depression in Croatian Subbasin
(Pannonian Basin) the organic matter is found to originate from the Middle
Miocene source where algal (or reworked algal) biomass was deposited under
suboxsic conditions. The source reached different maturity level in
dependence on the burial depth, i.e. temperature. So, it generates light
dry gas, oil, condensate, wet gas and heavy dry gas. Oils are found to be
predominantly well preserved from alteration in traps. Only few of them
underwent biodegradation. Large number of investigated oil seeps and
outcrops from Central Dalmatia as well as two oil samples might be
discriminated into Triassic, Jurassic and Cretaceous group and their
subgroups. As hydrocarbon precursor cyanobacterial biomass is often
recognised what goes well with persisting Mesozoic carbonate platform in
Adriatic. Deposition environment was marine, often hypersaline and
prevailingly anoxic. Organic matter reached relatively low maturity level
due to low geothermal gradient in that region. Two oils, explored in
Central Adriatic, are found not to be altered but oil seeps were
biodegraded in different range up the severe one. A detailed study of the
type and quantity of sulphur in the oil-source outcrops of Upper Jurassic
strata in Dinarides, was performed. Organic compounds containing sulphur,
were paid attention. The data achieved present a modern geochemical base
for genetic correlations, for the determination of the maturation rank of
the related organic matter as well as for investigation of the deposition
environment.
Research goals: The main purpose of the research is to learn about
the type and distribution of the hydrocarbons in Croatia, especially in
order to increase the explored oil and gas traps. Suorce rock in Croatian
Subbasin which supplies hydrocarbons into the oil, gas and condensate
traps in Drava Depression, i. e. into the oil traps in Slavonija-Srijem
Depression is identified. Triassic, Jurassic and two Cretaceous source
rocks in Central Dalmatia are indicated. For them the proper burial depth
needed to reach the oil window is determined. That provides theindication
of the prospectives for further oil and gas exploration in a part of
Adriatic and Dinarides. For that sedimentary area the influence of the
source maturity from the influence of biodegradation, to hydrocarbon
viscosity, has been discriminated. The base for determination of genetic
correlations, maturity and deposition environment of Upper Jurassic
source-rock from Dinarides is obtained, based on the distribution of
sulphur compounds.
COOPERATION - INSTITUTIONS
Name of institution
: INA-NAFTAPLIN, Šubićeva 29, Zagreb Type of institution: Economical/Production Type of cooperation: Occasional exchange of information City: 10000 - Zagreb, Croatia
Name of institution
: PMF, Zavod za geologiju i paleontologiju,
Zvonimirova 8, Zagreb Type of institution: University/Faculty Type of cooperation: Occasional exchange of information City: 10000 - Zagreb, Croatia
Name of institution
: CHEVRON-COFRC, Richmond and La Habra, CA.
USA Type of institution: Economical/Production Type of cooperation: Occasional exchange of information City: 90631 - Richmond and La Habra, California, USA
Name of institution
: CHEVRON-COPI, San Ramon, CA. USA Type of institution: Economical/Production Type of cooperation: Occasional exchange of information City: 94583 - San Ramon, California, USA
Name of institution
: STANFORD UNIVERSITY, Stanford, CA. USA Type of institution: University/Faculty Type of cooperation: Occasional exchange of information City: 94305 - Stanford, California, USA
Name of institution
: AGIP, San Donato Milanese, Italia Type of institution: Economical/Production Type of cooperation: Occasional exchange of information City: San Donato Milanese, Italija
Name of institution
: GEOLOŠKI INSTITUT HRVATSKE, Sachsova 2,
Zagreb Type of institution: State institute Type of cooperation: Occasional exchange of information City: 10000 - Zagreb, Croatia
Name of institution
: KEMIJSKO-TEHNOLOŠKI FAKULTET, Marulićev trg
19, Zagreb Type of institution: University/Faculty Type of cooperation: Occasional exchange of information City: 10000 - Zagreb, Croatia Other information about the project.