The discovery of oil in the Peruvian
Amazon is an extraordinary story of
perseverance, courage and resolve.
The immense challenges of terrain,
weather, finance and bureaucracy might
never have been overcome had it not
been for the vision of pioneering geologist
Robert Moran.
Moran grew up amid the California
oil boom at the turn of the 20th century.
At that time, California was the largest
oil-producing state in the nation, with an
annual production of 77 million barrels in
1910. Oil derricks were prolific in many
parts of southern California and all manner
of people flocked to the area to seek their
fortune.
Given this environment, it was natural
for Moran to take an extended break from
his geology studies at Stanford University
to work as a roustabout at the nearby
Santa Maria oil field. Then, after graduating
in 1907, he worked as a geologist for the
Southern Pacific Railroad, Associated Oil
and Standard Oil of California. Such was
the fast-moving nature of the industry at
the time that, with only four years’ industry
experience, Moran set up as a consulting
geologist and engineer.
“After working in the geological
department of several major oil companies,
I took off on my own – sometimes
working on a consulting basis for various
companies, both large and small,” he
said. “Since 1911, I have followed the
business of oil finding and have met with
considerable success. The results have
been out of all proportion to the amount of
money at my command.”
The key anticlinal theory of oil and gas
accumulation had been published by T.
Sterry Hunt in 1861 and had been used
successfully by explorers such as I.C.
White in Wyoming. Despite this, in the early
part of the 20th century, geologists often
conflicted with the practical oilmen who
still largely controlled the industry. One
oil producer reportedly commented, “If I
wanted to make sure of a dry hole, I would
employ a geologist to select a location.”
Flying Over Peru
By 1928, Moran’s attention had turned
to opportunities overseas and he was
invited by his uncle, Daniel Breck, who ran
the Selden-Breck Construction Company,
to review a number of irrigation projects
along the coast of Peru. While he was
there, Moran was offered the opportunity
to evaluate a railway that was to run from
the Andes near Cerro de Pasco across the
heavily forested eastern flank of the Andes,
known as the “montaña,” to Pucallpa in
the Amazon Basin. The Peruvian navy ran
an airmail service that flew close to the
proposed railway and a reconnaissance
flight in an open cockpit biplane was
organised for Moran.
As the flight approached Pucallpa,
Moran spotted a ridge in the rainforest
ahead and, as the plane overflew the ridge,
he saw a series of in-facing scarps forming
an elliptical pattern which meant only one
thing to him: an anticline. For Moran this
dome-shaped geological structure was a
key ingredient for success. He asked the
pilot to circle a few times and took some
16-millimeter cine footage and photos.
Moran named the anticline after nearby
Agua Caliente, the site of several hot
springs.
The U.S. Department of Commerce’s
Handbook of Peru contained a sketch map
showing several localities where seepages
of oil occurred. Moran was particularly
interested in Jurassic limestones near
Cerro de Pasco that contained bitumen.
Given the vast size of the anticline, Moran
and Breck decided to explore the area.
This was a hugely ambitious undertaking
for a number of reasons. The geology
of the area was very poorly understood,
as the Amazon Basin of South America
was completely undrilled and only a few
geologists had previously visited the area.
The locality of the anticline was difficult
to access, and in the event that their
evaluation proved positive, they would have
to raise the funds to drill a well. This would
require the import of a drilling rig from
the United States, then 3,000 miles up the
Amazon from the Atlantic coast of Brazil.
Even with a successful well, the market
for oil in the middle of the Amazon was far
from obvious.
Over the Hill to Masisea
Moran was not deterred by these
challenges and Selden-Breck signed an
exploration concession with the Peruvian
government along the route of the
proposed railroad. He set about arranging
a field party to explore the area and hired
fellow Californian geologists Douglas Fyfe
and Glenn Earl to assist him in the work.
The base for their fieldwork was to be
the airbase of the Peruvian navy airmail
service at Masisea on the banks of the
Ucayali River. From there the Agua Caliente
anticline could be accessed in one day by
motor-powered canoe.
The journey from Lima to the field area
was euphemistically described as “over
the hill to Masisea.” The hill in question
was the Andes mountains which Fyfe and
Earl traversed by train and truck to San
Ramón. From San Ramón, the two men
embarked on a seven-day hike through the
montaña, along the 180-kilometer Pichis
Trail to Puerto Jessup on the Azupizu River
in the Amazon Basin. They transported all
their field equipment by mule, including an
outboard motor.
They purchased a dugout canoe at
Puerto Jessup and floated downstream
for 14 days, until they eventually arrived
at Masisea some 300 kilometers away.
They studied and measured the numerous
outcrops along the route, which aided their
evaluation of the large concession. From
Masisea, they travelled upstream to the
field area on the Pachitea River in a dugout
canoe powered by the outboard motor they
had brought from the United States.
Moran’s main competitor in Peru was
Standard Oil of New Jersey, which had
been active in the Amazon Basin for several
years in the 1920s. Standard Oil, however,
did not have the benefit of the aerial
reconnaissance that provided such focus
for Moran and his team. They carried out
fieldwork over a vast area and it would have
taken them many years to focus in on a
prospective area, such as the Agua Caliente
anticline, using fieldwork alone.
Until the early 1920s, the Amazon Basin
had been the domain of explorers and
people working in the exploitation of rubber
during the rubber boom, which lasted from
1879 to 1912.
Geologist Joseph Singewald described
the situation, “Few other than venturesome
explorers and intrepid rubber men have
traversed the canyon. The records of
the former are written as tales of travel
and adventure, are chiefly narrative and
generally abound in exaggeration of the
perils of the region. The rubber men risk
great dangers and perform wonderful feats
of exploration but are neither interested in
nor capable of leaving a written account of
the territory they traverse.”
To address this deficiency, a small
number of academics like Singewald
had carried out expeditions to explore
and describe the geology along some
of the major rivers. At the time of
Moran’s overflight, only a handful of
academic papers had been published
and the stratigraphy was relatively poorly
understood, especially in terms of a
potential petroleum system. The objectives
of the fieldwork were therefore twofold:
firstly, to map the structural detail of the
Agua Caliente anticline and secondly, to
understand the stratigraphy of the area
and the potential for reservoirs and seals.
If they could find any oil seeps, it would
indicate oil generation in the area.
Fieldwork in the Rainforest
The outcrops around the anticline were
numerous and the fieldwork strategy was
to cut paths through the dense rainforest
from the Pachitea River over the anticline.
This was extremely arduous work, and the
geologists employed a team of eight locals
to assist them. The traverses were paced
and the dip and strike of outcrops were
measured with a Brunton compass. The
elevation was measured with a barometer,
and using these data they were able to
construct a detailed structure map of the
anticline.
To the south of the Agua Caliente
anticline, two tributaries of the Pachitea
River rose in the Shira Mountains. If the
men could make their way up these narrow
rivers, they hoped to be able to traverse
a complete section of the geology. In
particular they were keen to establish
whether the key Jurassic limestones that
contained bitumen elsewhere were present
in the area.
Progress up the tributaries was difficult
and after a short distance they were unable
to proceed any farther in their small canoe.
They had to wade upstream, dragging the
dugout canoe containing their precious
food supplies and equipment. After three
days of persevering through progressively
older stratigraphy, they abandoned the
canoe and proceeded on foot through
the river, clambering over boulders and
fighting against the current. The further
they travelled away from the Pachitea River,
the greater the chance of encountering
the feared head-shrinking Cashibos, and
they spotted several paths that could
have been made by these indigenous
peoples. Sourcing sufficient food was a
challenge. The field party had assumed
that they would be able to hunt and fish to
supplement the basic foodstuffs, such as
rice that they were carrying. Unfortunately,
this proved not to be the case and
increasing hunger affected morale.
Wishing to return to the Pachitea,
their local workers hid the remaining
food supplies, claiming that the Cashibos
had stolen them, but Moran carried on
regardless. The other challenge they
faced were biting insects that were
unbearable at times and necessitated
the use of mosquito nets at nights. After
five days, they finally encountered the
contact between a sandstone sequence
and limestones which they presumed
to be Jurassic in age and correlative
with the bitumen-bearing limestones
in the Cerro de Pasco region farther to
the west. They collected fossils from
large blocks of limestone in the riverbed,
and despite an age-dating that showed
a Permian age, they incorrectly stuck
with the interpretation of Jurassic age,
assuming that the boulders were from
an older limestone that had been carried
downstream.
After two field seasons, Moran and
Fyfe were able to put together a technical
case for the Agua Caliente anticline.
From their mapping, they established
that the closure on the anticline was 150
square kilometers with a vertical relief of
975 meters. From the outcrop data they
prognosed a reservoir and seal within the
Agua Caliente Sandstone Series, with the
oil seepages that they had found occurring
at the interface between them. Although
Moran did not calculate volumes, from
the structure we can estimate prospective
resources of four billion barrels – an
enormous resource by any standards.
Drilling the Well
The challenge of understanding the
subsurface was only the beginning for
Moran. Since his initial flight over the Agua
Caliente anticline, the Great Depression
had taken hold in the United States and
around the world. Oil prices had crashed
from $1.70 to $0.65. The dreadful financial
environment made the task of raising funds
to drill a well in a faraway place such as
Peru very difficult. This was compounded
by the fact that, as a result of numerous
bank closures and dire trading conditions,
Moran’s partner Selden-Breck Construction
were unable to meet their share of the
ongoing expenses. He had to dig deep
into his own pockets to keep the venture
afloat. After several aborted deals, Moran
eventually raised the money for a well from
wealthy California investors.
Armed with only a few basic tools and
an untrained workforce, it required an
enormous construction effort to build a
port on the Pachitea to receive the rig and
an 11-kilometer road to the wellsite, which
was located on a hill 700 meters above
the port. A rig imported from the United
States eventually made it up the Amazon to
the well site, a journey of more than 3,000
miles from the Atlantic coast of Brazil.
The Agua Caliente-1 well was spudded
in 1938, the first well to be drilled in the
Sub-Andean Basins of Peru, Bolivia,
Ecuador and Colombia. The well was a
success, although the anticline was not
full to spill and the discovery was modest
in size compared to its potential. The
commercialization of the discovery and the
question of whether Moran received his
due rewards is another story. Stay tuned for
that next year.
Read More
Moran joined AAPG in 1919 and was
made an Honorary Member 40 years later.
He died in 1961, and his descendants had
the foresight to leave his papers, including
field diaries, correspondence, and reports
to the libraries of Stanford University and
the University of California Santa Barbara.
From these I have unravelled a
remarkable story that not only provides
unique insights into the challenges faced
by early explorers but also Moran’s singular
drive, perseverance and vision that saw the
venture progress from initial observation
from the air to oil discovery. The full story
has been published in a book called “Agua
Caliente,” available on Amazon.com.