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VENEZUELA
South America
Venezuela is the largest oil producer in South
America. The country’s economy is dependent on the success of its
petroleum industry. Venezuela is also very important for the development of heavy oil
extraction and refining technology and it has large extra-heavy oil
potential for conversion to synthetic oil.
Rifting during the separation of North and South America
created the country's prolific onshore basins. The first well
was drilled in 1878 to the south of Lake Maracaibo, but it was not until
1907 that companies began exploration. Shell’s well on the La Rosa Field
on the shores of Lake Maracaibo blew out with a flow rate of over
100,000 Bbls per day having penetrated a highly fractured Cretaceous
limestone reservoir.

Western Venezuela was the first region to produce oil in
the country - on the eastern shore of Lake Maracaibo. Initial
discoveries were on land but their proximity to the lake led to
exploration in shallow waters in the 1920s and eventually into deeper
waters. This, together with similar efforts in the Caspian Sea
and Gulf of Mexico, was the foundation for offshore operations
developing worldwide.
The main source rock for oil is the
La Luna Formation of Late Cretaceous age, also responsible for oil in Mexico and the
Gulf Coast of the USA. It extends along all of Western Venezuela and
Colombia, and is equivalent to the Querecal Formation source rock of eastern Venezuela.
Eastern Venezuelan oil exploration goes back to the 1910s
when bitumen was extracted from the Guanoco pitch lake. In the 1920s and
1930s several fields were discovered in scattered areas in the jungle,
swamps and plains. However, it was not until the discovery of the giant
El Furrial field in 1986 that the eastern area became especially
important.
Two sub-basins, the western Guárico and the eastern
Matuŕin, are bordered to the south by thinning Cretaceous and Tertiary
units that create traps and asphalt seals in the Orinoco Belt. This Belt (known
as La Faja) north of the Orinoco River
contains heavy and extra-heavy oil. It is a vast reserve stretching 800
kms from east to west and 200 kms from north to south.
Venezuelan was a key country in the formation of OPEC in 1960.
Soon after the Venezuelan government began to pass laws qualifying the existing concessions, which paved
the way for a full nationalisation in 1975, and the creation of the
national company, Petroleos de Venezuela SA (PDVSA).
In 1995 invitations were offered for participation with
PDVSA in
areas throughout the country and since then releases have been
concentrated around marginal fields and reactivation programmes in the
heavy oil areas. In 2000, around 44 companies from 15 countries were
involved in operating agreements in 42 areas but changes in terms have
now
forced many to leave.
Offshore: Although Venezuela is rich in oil and
gas it has no offshore production outside of Lake Maracaibo, the first
region to produce oil in the country. Initial discoveries here were on
land but their proximity to the lake led, in the 1920s, to exploration
in very shallow waters with barge-mounted drilling rigs designed
especially for the purpose.
Outside of Lake Maracaibo the country has a
long coastline and a wide shelf only limited by the territorial waters
of the formerly Dutch volcanic islands of Aruba, Curacao and Bonaire as
well as by Trinidad and Tobago on the east.
However, the prolific onshore Venezuelan oil basins do
not appear to have many offshore parallels because they are
disrupted by transcurrent faulting along the southern edge of the
Antillean island arc as oceanic crust of the Caribbean Sea moved
eastwards. Nevertheless several small, undeveloped oil discoveries
have been made east of the Paraguana Peninsula off Falcon State in
western Venezuela and in the Gulf of Paria west of Trinidad. The country
has licensed blocks to foreign companies to exploit these resources.
It is in gas and condensate drilling that offshore
Venezuela is becoming especially important. A string of gas and
gas/condensate fields have been discovered offshore eastern Venezuela
both west of Trinidad, north of the Paria peninsula and south of
Trinidad on the Plataforma Deltana of the Orinoco River.
Projects are in their initial stages in both these
regions to develop the gas. Gas may also be expected in the Venezuelan
Gulf region in Falcon State, west of the Paraguana Peninsula.
Venezuela’s State oil company, PDVSA, has created the Organización Costa
Afuera (Offshore Organization), to develop and market the gas projects.
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