Petroleum Geology of Libya

Don Hallett, Daniel Clark-Lowes

• Publisher: Elsevier
• Year: 2017
• ISBN:
  9780444635198
• Edition: 2
• Topic: Technology & Engineering
• Subtopic: Chemical & Biochemical Engineering
• Index: Technology & Engineering

Petroleum Geology of Libya, Second Edition, systematically reviews the exploration history, plate tectonics, structural evolution, stratigraphy, geochemistry and petroleum systems of Libya, and includes valuable new chapters on oil and gas fields, production, and reserves. Since the previous edition, published in 2002, there have been numerous developments in Libya, including the lifting of sanctions, a new licensing system, with licensing rounds in 2004, 2005, 2006, and 2007, many new exploratory wells, discoveries and field developments, and a change of regime.

A large amount of new data has been published on the geology of Libya in the past fourteen years, but it is widely scattered through the literature. Much of the older data has been superseded, and several of the key publications, especially those published in Libya, are difficult to access. This second edition provides an updated source of reference which incorporates much new information, particularly on petroleum systems, reserves, oil and gas fields, play fairways, and remaining potential. It presents the results of recent research and a detailed description of Libyan offshore geology. The book includes an extensive and comprehensive bibliography.

• Presents over 180 full colour illustrations including maps, diagrams and charts, illustrating the key concepts in a clear and concise manner
• Authored by two recognized world authorities on geology in Libya, with over 40 years' experience in Libya between them
• Provides an expanded and updated version of the bestselling previous edition, nicknamed the Explorationist's Bible
• Lays the foundation for the post-revolution exploration age in Libya

Chapter 1

History of Oil and Gas Exploration

Abstract

The first hydrocarbon exploration licences in Libya were awarded in 1955. Exploration began in Cyrenaica, and adjacent to the Algerian frontier, but quickly switched to the Sirt Basin following large discoveries at Zahrah-Hufrah, Zaltan and Amal. By the end of 1963 20 billion barrels of recoverable reserves had been found. Production began in 1961 and reached over 3 million barrels per day in 1969, by which time 14 giant fields had been discovered. Following the Libyan revolution of 1969 activity slowed as the government established state participation in all licences and nationalised the Libyan interests of a number of companies. By 1974 state companies held a dominant position. Production fell to around 1.3 million barrels per day and remained at or near this level for many years. Exploration drilling also declined from over 100 exploration wildcat wells per year to an average of only 30 through the 80s and 90s. Production sharing licences were introduced in 1974 and with minor modifications continued until 2005. The Bouri field was discovered in 1977 and proved to be the largest offshore oil field in the Mediterranean. Political events and sanctions restricted growth during the 1980s and 1990s, but in 2005 with the lifting of sanctions and the establishment of a new licence structure, activity increased and several significant discoveries were made in the Murzuq Basin and offshore. Production rose to over 1.8 million barrels per day and the number of exploration wildcat wells exceeded 50 per year for the first time since 1969. The overthrow of the Qadafi regime in 2011 plunged the industry into turmoil; exploration drilling was greatly reduced, and oil and gas production since then has been erratic.

Keywords

Libya; Oil and gas; Licensing; Exploration history; Discoveries; Giant fields; Disputes; Nationalisation; State oil companies; Political influences; Oil price; Production

Outline

1.1 Introduction

1.2 The Decade 1950–59

1.3 The Decade 1960–69

1.4 The Decade 1970–79

1.5 The Decade 1980–89

1.6 The Decade 1990–99

1.7 The Decade 2000–09

1.8 The Period 2010–15

1.1 Introduction

Libya has known many masters—Phoenician, Carthaginian, Greek, Roman, Byzantine, Arab, Ottoman, Italian, and Allied military control after the Second World War. There was little organised scientific activity before the annexation of Libya by Italy in 1911, although a number of expeditions, some with scientific interests, passed through Libya in the 19th century. The main objective of these expeditions, mostly organised by the London-based African Association, was to explore the region southwards from Murzuq to Timbuktu, determine the course of the Niger River and assess the commercial potential of the area. The earliest of these expeditions was undertaken by Friedrich Hornemann who travelled with a camel caravan from Egypt into Libya passing through the oases of Siwa and Awjilah, and then across the Haruj al Aswad to Murzuq, and subsequently to Tripoli. He returned to Murzuq in Aug. 1799 and was never seen again. In 1817 a military expedition led by the Bey of Tripoli traversed the coastal route from Tripoli to Cyrenaica and was accompanied by an Italian doctor, Paolo Della Cella, who wrote an account of the expedition and noted the presence of fossils in Cyrenaica. This is the earliest known reference to geology in Libya. The African Association's second attempt, this time starting from Tripoli, was made by George Lyon and Joseph Ritchie in 1819 but only reached Murzuq where Ritchie died of fever. In 1822 a better equipped but poorly led expedition set out under the joint leadership of Dixon Denham, an army lieutenant and Hugh Clapperton a naval lieutenant, accompanied by a naval surgeon, Walter Oudney. The expedition reached Lake Chad, but Oudney died and Denham returned to England. Clapperton continued but was halted just 5 days march from the Niger by a local sheikh. Most tragic of all was the expedition of Gordon Laing in 1826. He became the first European to reach Timbuktu, but was murdered by his Tuareg guides as he returned through what is now Mali.¹

The first expedition with any pretensions of scientific enquiry was conducted by Dr Heinrich Barth who joined James Richardson's expedition in 1850, accompanied by geologist and astronomer Dr Adolf Overweg. The expedition crossed the Gharyan hills and the Hamadah al Hamra and Overweg collected fossils between Murzuq and Ghat which were later identified by Heinrich Beyrich as Carboniferous, the first record of Carboniferous rocks in North Africa. Richardson and Overweg both died on the expedition, but Barth explored the area between Murzuq, Lake Chad and Timbuktu, publishing a detailed account of his travels in 1857/58. Other explorers continued to explore the area into the 1860s and 1870s. At a time when borders were nonexistent French geologists, working in eastern Algeria in the 1880s, identified Devonian rocks in the Jabal Akakus and Cretaceous rocks on the Hamadah al Hamra. Both of these areas are now in Libya. Finally, after an Italian expedition in 1881 the Ottoman authorities discouraged further exploration, and the European powers turned their attention to other areas.²

In 1908 J.W. Gregory, professor of Geology at Glasgow University, led an expedition to Cyrenaica under the auspices of the Jewish Territorial Organization to determine whether Cyrenaica would be suitable as a home for Jewish refugees recently displaced from eastern Europe. This is not as strange as it may first appear as Jews had a long and prominent history in Cyrenaica dating back to Roman times. The expedition studied the geography, geology, agriculture and water supply of the area and Gregory published an account of the geology in 1911 which described and named seven Tertiary formations, some of which are still in use today. The plan for a Jewish settlement in Cyrenaica however was abandoned.³

Libya was invaded by the Italians at the beginning of the Italian–Turkish war of 1911. The Italians expected to be regarded as liberators by the Libyans, but this was a grave miscalculation, which led to 20 years of almost incessant warfare. The Italian hold on Libya was tenuous until 1922 when Mussolini's Fascists seized control in Italy. They then embarked on La Riconquista of Libya under generals Volpi and Graziani, which developed into a protracted guerrilla war from 1922 to 1932, a war described as ‘long, petty and spiteful’. The western part of Libya was gradually subdued, but Murzuq, the capital of Fezzan, was not conquered until 1930. In Cyrenaica, the Libyans, led by Omar Mukhtar, a local Sanussi sheikh, put up tougher resistance, but in 1930 Graziani was appointed Vice-Governor of Cyrenaica. Using the brutal methods for which he was well-known, he confiscated estates, exiled leaders, poisoned wells and erected a 200 km barbed wire fence along the border with Egypt. Nomads and their flocks were herded into concentration camps, one of which was located at Marsa al Brayqah where the future Esso port and terminal were to be built. With superior manpower and equipment Libyan resistance was finally crushed. Omar Mukhtar was captured in Sep. 1931 and after a summary trial he was hanged at Soluq.⁴

With the Italians now in full control they set about establishing the so-called Fourth Shore. Confiscated estates and ownerless land was appropriated and sold off cheaply. Mussolini encouraged Italian peasants and the unemployed to acquire land, but the hot, dry climate made farming difficult and the economic crisis of the early 1930s made progress painfully slow. In 1937 there were only 1,300 Italian immigrant families farming in Libya, but under the leadership of Italo Balbo, Governor-General of Libya, a further 20,000 immigrants were shipped to Libya in Dec. 1938 to occupy farms prepared for them in advance by the Fascist authorities.⁵ Balbo suffered the unusual fate of being killed by friendly fire whilst flying over Tubruq in 1940 when his plane was shot down by Italian antiaircraft guns.

In these circumstances it is surprising that Italian geologists made any notable progress in examining and documenting the geology of Libya, but the first rudimentary geological map of the accessible parts of Libya was published in 1913 at a scale of 1:6,000,000,⁶ and a number of papers were published on practical aspects such as water supply, minerals and building material in the period up to the First World War. In the 1920s a second generation of Italian geologists led by Ardito Desio produced reports on some of the more remote regions of Libya. Desio was a charismatic figure: geologist, cartographer, explorer and mountaineer. In 1926 he led a geological expedition to the Al Jaghbub oasis on the border with Egypt, and in 1931 he undertook a more ambitious expedition by camel caravan across the Sahara to the border of Sudan, followed by an expedition to the Tibisti mountains in 1935. He became director of the Libyan Geological Service from 1936 to 1940 when he reported on deep aquifers, which did much to stimulate agriculture, and on surface oil seeps which led to the birth of the Libyan oil industry.⁷ During his long career he published over 120 papers on the geology of Libya during the period 1927–75.⁸ Traces of methane were reported in a water well drilled near Tripoli in 1914⁹ and subsequently gas was noticed in several wells drilled on the coastal plain and on the Jabal Nafusah. In 1926 Crema found traces of oil in a well at Sidi al Masri in the suburbs of Tripoli.¹⁰ Under Desio's leadership Agip was persuaded to conduct a 2-year reconnaissance campaign and to drill a 5,000 ft exploration well near Tripoli, which proved to be dry, but it was during this period that Desio predicted that the Sirt Basin would be a favourable area for hydrocarbon gene...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Figures
• Preface to the Second Edition
• Chapter 1: History of Oil and Gas Exploration
• Chapter 2: Plate Tectonic History
• Chapter 3: Stratigraphy
• Chapter 4: Structure
• Chapter 5: Petroleum Geochemistry
• Chapter 6: Petroleum Systems and Play Fairways
• Chapter 7: Oil and Gas Fields of Libya
• Chapter 8: Future Exploration and Exploitation Potential
• Bibliography
• Index