EL SALVADOR: ASSESSMENT OF PETROLEUM POTENTIAL

• Document Type: CREST
• Collection: General CIA Records
• Document Number (FOIA) /ESDN (CREST): CIA-RDP85T01058R000405140001-2
• Release Decision: RIPPUB
• Original Classification: C
• Document Page Count: 8
• Document Creation Date: December 22, 2016
• Document Release Date: November 13, 2009
• Sequence Number: 1
• Publication Date: October 17, 1985
• Content Type: MEMO

Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
44
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
Central Intelligence Agency
17 OCT i88
MEMORANDUM FOR: Mr. Ronald K. Lohrding
Assistant Director for Industrial and
International Initiatives
Los Alamos Scientific Laboratories
VIA: David Wigg
National Security Council
SUBJECT: El Salvador: Assessment of Petroleum Potential
Attached is a technical assessment of the petroleum geology of
El Salvador. The body of the report is intended for a technical readership
and is unclassified when detached fran the summary. We intend to canple to
similar reports assessing the hydrocarbon potential of other Central American
ccuntries. We will, of course, forward copies of these reports to you as they
became available. If we can be of any further assistance to you on this or
any related matter, please call
25X1
25X1
Attachment:
El Salvador: Assessment of
GI M 85-10242, October 1985
25X1
25X1
STAT
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
OGI/SRD/PRB,I I(15 October 1985)
Distribution:
1 - R. Lohrding, Los Alamos
1 - SA/DDCI
1 - ExDir
1 - DDI
1 - DDI/PES
1 - NIO/LA
1 - NIO/ECON
1 - D/ALA
1 - ALA/MCD/CAS
1 - DD/OGI, D/OGI
1 - CPAS/ISS
5 - CPAS/ICB
1 - OGI/PG/Ch
3 - OGI/EXS/PG
1 - Ch/SRD
1 - Ch/PRB
1 - OGI/TNAD/TAB
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
I I
Central Intelligence Agency
Washington, D. C.20505
DIRECTORATE OF INTELLIGENCE
15 October 1985
El Salvador: Assessment of Petroleum Potential
Sunvary
Examination of the geology of El Salvador indicates that the petroleum
potential of the country is extremely poor. The absence of marine sedimentary
basins onshore and the lack or immaturity of offshore source beds preclude the
presence of significant petroleum accumulations. The forearc basin off El
Salvador's coast is geologically the most promising area for the possible
accumulation of petroleum. Nevertheless, our analysis indicates that even
under the best of circumstances the amount of petroleum that could have been
generated in this basin is so small that it would not even be adequate to meet
El Salvador's relatively meager domestic oil requirements-currently estimated
at some 11,000 b/d.
In view of this pessimistic assessment, El Salvador will need to continue
relying on imported oil, mainly from t11exico and Venezuela, to meet all of its
domestic requirements. In 1984, El Salvador's oil import bill exceeded $100
million. We believe that oil imports will increase to about 20,000 b/d by the
mid-1990s with nearly all of the growth in consumption occurring in the
transportation and industrial sectors.
Hydroelectric and geothermal power currently provide about 75 percent of
El Salvador's energy needs. Planned expansion of hydroelectric and geothermal
plants will provide excess electrical generating capacity, but few additional
possibilities exist for El Salvador to substitute electricity for oil. If
hostilities were ended, El Salvador might be able to export surplus
electricity to neighboring countries and lessen the financial burden of
importing oil.
This memorandum was prepared by Petroleum Resources Branch,
Office of Global Issues. The in ormation contained herein is updated to
15 October 1985. Comments may be directed to Chief, Strategic
Resources Division,
25X1
25X1
25X1
STAT
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
UL' L -t Olr tru
El Salvador: Assessment of Petroleum Potential
Regional Setting
El Salvador is located in the northern geologic province of Central
America. This province, containing Guatemala, Honduras, El Salvador and
Northern Nicaragua, is underlain by continental crust basement of Proterozoic
and early Paleozoic age. Rock types are metasediments, anatexites, and
plutonics. This basement is overlain by upper Paleozoic, Mesozoic, and
Tertiary sediments which have undergone middle Permian and Cretaceous-Tertiary
deformation. The start of subduction along the Middle American Trench during
the Miocene resulted in periodic andesitic volcanism which continues to the
Present.
Geology of El Salvador
The oldest basement rocks in El Salvador are pre-Triassic metasediments
of the Honduras Massif. These rocks consist of phyllites, sericite schists
and graphite schists. The extent of. these rocks is unknown, but they outcrop
along the Honduras border and form the core of the Honduran Massif to the
north. They may form the basement under much of El Salvador.
Pre-Triassic metasediments are unconformably overlain by upper Cretaceous
red sandstones, marls, and limestones. These sediments outcrop in
northwestern El Salvador and probably underlie younger volcanics which cover
most of the country. These sediments are known as the tletapan Formation, and
they correlate with the Todos Santos Formation, Yojoa Group, and Valle de
Angelles Formation of central Honduras. Unlike areas to the north, the
Mesozoic in El Salvador is poorly developed and represents the marginal basin
facies of the thicker and more complete Mesozoic sequence to the north.
Uplift and erosion at the end of the Mesozoic resulted in the removal of the
Mesozoic over most of El Salvador and created an unconformity between Mesozoic
sediments and Tertiary volcanics.
The start of subduction along the Middle American Trench during the
Miocene resulted in a period of widespread volcanism which continues to the
Present. Miocene volcanics occur in the northwest corner of the country;
Pliocene volcanics occur in a belt throughout central El Salvador, and
Pliocene to Recent volcanics occur along El Salvador's Pacific coast.
1Weyl, R., 1980, Geology of Central America., Berlin, Gebruder-Borntraeger.
2Fairbridge, W., 1975, El Salvador., in the Encyclopedia of Wbrld Regional
Geology Part 1: Western Hemisphere. Dow Huchinson and Ross Inc., p. 270-272.
3Wiesemann, G., 1975, Remarks on the Geologic Structure-of the Republic of El
Salvador., Mitt. Geol.-Palaont. Inst. Univ. Hamburg, 44, 557-574, Hamburg.
2
UNCLASSIFIED
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
VL1L.ir]//.LL 1LL
The start of subduction along the Middle American Trench also formed a
trench-accretionary-wedge-forearc basin canplex off El Salvador's Pacific
coast. Drilling by the Glamar Explorer during Leg 67 and offshore geophysical
surveys show that the accreted sediments reach a depth of 2300 meters. Rock
types are upper Cretaceous to Pliocene micritic limestones, mudstones and
claystones. Pliocene to Recent sediments are unconsolidated diatomaceous muds
with numerous volcanic ash layers.
The forearc basin extends along the Latin American coast from the Nicoya
Peninsula in Costa Rica to the Gulf of Tehenaupec off Plexico.4 Off the coast
of El Salvador this basin contains up to 10,000 meters of Cretaceous,
Paleocene, Eocene, Miocene and Pleistocene sediments. The Lower Cretaceous
and Lower Paleocene sediments were deposits at abyssal depths and are canposed
of limestones and calcareous schists. The Upper Paleocene, Eocene, Miocene
and Pleistocene sediments were deposited at lower to middle bathyal depths and
consist of limestones, mudstones, and tuffaceous arrenites.2, 5
Petroleum Potential
Evaluation of the petroleum potential of El Salvador is hampered by the
small amount of onshore and offshore subsurface data. No exploration wells
have been drilled on or offshore and little seismic exploration work has taken
place. The only sources of data are the results of Leg 67 of the Glamar
Explorer Drill Program, and data presented by Seely (1978) on the forearc
basin off El Salvador rs coast. These sources and tectonic reconstructions
presented in Weyl (1980) were used to evaluate El Salvador's petroleum
potential.1
The petroleum potential of El Salvador is limited to the following areas:
o Mesozoic sediments of the Metapan Formation;
o sediments in the offshore accretionary wedge; and
o sediments in the forearc basin off El Salvador's coast.
Although sedimentary equivalents of the Metapan Formation are petroleum
bearing in the areas north of El Salvador, the formation has no petroleum
potential in El Salvador. Late Mesozoic uplift and erosion removed the
Metapan Formation over much of El Salvador, and where it does occur it is thin
and disturbed.
4Seely, D.R., 1978, The Evolution of Structural Highs Bordering Major Forearc
Basins., in American Association of Petroleum Geologists Ple oir 26, p. 245-
260.
5Coulbourn, W.P., Hesse, R., Azema, J., Shiki, T., A Summary of Deep Sea
Drilling Project Leg 67 Sites: The Middle America Trench and Slope off
Guatemala., in Initial Reports of the Deep Sea Drilling Project, V.67, p. 759-
777.
3
UNCLASSIFIED
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
uL4L1.1~051r Inu
Sediments in the offshore accretionary wedge are not petroleum bearing.
Investigations by the Glanar Explorer show that organic-rich hemipelagic
sediments are being deposited between 300 and 1500 meters below sea level.
Sediments below 1500 meters are poor in organics and therefore cannot be
considered petroleum source beds. Examination of drill core from the
accretionary wedge shows that some hydrocarbon generation is occurring within
the organic-rich interval. The sediments are still too immature, however, for
significant hydrocarbon generation, and the high sulfur content of the
sediments may prevent formation of hydrocarbons due to reaction with
lipids.
The forearc basin off El Salvador's coast offers the best chance for the
occurrence of petroleum, but a number of factors indicate that it does not
contain commercial accumulations of petroleum. This basin extends along the
Central American Coast from the Nicoya Peninsula in Costa Rica to the Gulf of
Tehauntepec off Mexico's Pacific coast and contains up to 10,000 meters of
Lower Cretaceous, Paleocene, Eocene, Miocene and Pliestocene sediments. Lower
Cretaceous to Lower Paleocene sediments were deposited at abyssal depths.
This indicates that the organic content of these sediments is too low for them
to have been petroleum source beds. ..Upper Paleocene and Eocene sediments were
deposits at lower to middle bathyal depths. Pre-Miocene sediments off the
Pacific coast of Tatin America are organically poor no matter what their depth
of deposition is. This observation was confirmed in this area by results of
Glanar Explorer Leg 67. This eliminates these formations as petroleum source
beds. Application of the improved Lopatin's method to Miocene and Pleistocene
sediments indicates that these sediments are not mature enough to generate
petroleum. Therefore, these sediments cannot be considered petroleum source
beds.
Energy Outlook
Because of its lack of hydrocarbon resources, El Salvador will remain
totally dependent on imported oil to meet transportation and industrial
needs. Imports amounted to about 11,000 barrels per day (b/d) in 1984 and the
annual oil import bill exceeded $100 million. If trends over the last five
years continue, daily oil requirements could reach about 20,000 b/d by the
mid-1990s. There is little El Salvador can do to limit its dependence on
6Summerhayes, C.P., and Gilbert. D., 1981, Distribution, Origin, and
Hydrocarbon Potential of Organic Matter in Sediments from the Pacific Margin
of Guatemala., in Initial Reports of Deep Sea Drilling Project, V.67, p. 546-
595.
7Sumnerhayes, C.P., and Gilbert, D., 1980, Distribution, Origin and
Hydrocarbon Potential of Organic Matter in Sediments fran the Pacific Margin
of Southern Mexico., in Initial Reports of Deep Sea Drilling Project, V.67, p.
541-546.
8waples, D.W., 1980, Time and Temperature in Petroleum Formation Application
of Loptin's Method to Petroleum Exploration., AAPG Bul. V.64, No. 6, p. 916-
920.
4
UNCLASSIFIED
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85TO1058R000405140001-2
 Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2
UNCLASSIFIED
imports. Virtually all of present oil use and all of the projeced increase in
oil consumption will be in the transportation and industrial sectors, where
few, if any, interfuel substitution possibilities exist and where conservation
possiblities are very limited. Only about one percent of the imported oil is
used to generate electricity--a share unlikely to change much.
El Salvador has substantial hydroelectric and geothermal resources which
presently provide about 75 percent of the country's energy needs. Completion
of the San Lorenzo hydroelectric project will boost electric power generation
capacity to 2.3 gigawatt-hours--the energy equivalent of 3,700 b/d--and will
give El Salvador excess generating capacity. This surplus could increase if
plans to increase the capacity of the Ahuchapan geothermal plant are carried
out.
El Salvador will not be able to fully develop its hydroelectric and
geothermal potential until the guerrilla war ends. Power line transmission
towers are repeatedly dynamited and work on the San Lorenzo hydroelectric
project is being hampered by guerrilla attacks. El Salvador has been forced
to construct an oil-fired generating plant to assure a constant electric
supply for San Salvador. If hostilities end, the country's potential
generating capacity is more than adequate to meet any realistic increase in
electrical demand and will possibly provide an exportable surplus as well.
5
UNCLASSIFIED
Sanitized Copy Approved for Release 2009/11/13: CIA-RDP85T01058R000405140001-2