Mud volcanism is pne of the most interesting nature phenomenon, which occurs in many coun- tries of the world. However, Azerbaijan is unrivalled Geology Institute in number of volcanoes, variety of forms, freguency Azerbaijan Academy of of eruptions.Mud volcanoes differing from magmatic Sciences volcanoes on activity area astonish by their beauty, ALL ABOUT MUD but their direct connection with oil and gas system VOLCANOES attracts the great attention for study. Hundreds of monographies, scientific articles and popular-sci- ence brochures written by Azeri scientists are dedi- Editor: cated to the problems of mud volcanism. But this Dr. Rashid D. Jevanshir book is the first popular-science brochure about mud volcanoes written in English and it significantly extends the readers' circle, who are interested in The book is set up in Sci- this unigue nature phenomenon.This book com- entific-publishing sector of pletely corresponding to its title, elucidates on a GIA, prented by offset method in broad sphere of fundamental and practical aspects "Azerbaijan" of mud volcanism and at the same time the book Publishing House. doesn't yield the preceding publications on colorful arrangement.This book is written in very popular and accessible form for readers of any age and with Responsible for the issue a various career guidance and I think it will be en- Hafiz Abiyev. thusiastically received and supported. Tel.: 39-56-19 By editor 39-39-72

Fax: (99412) 39-41-39 "Azerbaijan" Publishing House order - 1 158 printing - 1000 INTRODUCTION

Volcanism is a mighty natural phenomenon circle of readers, discusses their distribution, the which startles the imagination with gigantic bursts of mechanism which drives them, the nature of their activ- . fire and eruptions, deafening roars and explosions. ity, the characteristics of the material from depth which There are few people'who know, however, about the is erupted from them, and the role of volcanoes in solv- less-distinguished relatives of magmatic volcanoes: ing a variety of fundamental atid practical problems. mud volcanoes. The book is rlchiy illustrated with colourful pho- Mud volcanism represents one of the most unu- tographs of various types of mud volcano. sual and interesting phenomena in nature, distinguish- Volcanoes and volcanic eruptions: we associate ing in a variety of forms and a specific character of ac- these words with mighty natural phenomena which tivity. That is why scholars, scientists and tourists have change the face of the Earth. They take us back to for many years been attracted to mud volcanoes. Rec- those distant times when the Earth was a lifeless ords of the massive fiery eruptions of mud volcanoes, planetary body on which the eiements of fire and water I raged. I which are always unexpected, and which capture the attention by their size and mystery, can be traced in ~vejonetoday knows all about magmatic vol- 1 the literature deep into antiquity. As long ago as the canoes. Tens of films have been made about them, 10th century, the great Arabian traveller, geographer hundreds of books, hundreds and thousands of scien- I and historian Masudi described, in his work "Meadows tific papers. And this is understandable, since magmatic of Gold and Mines of Precious Stones", one of the re- volcanoes are not only exotic phenomena, but a window markable eruptions which took place in the Caspian into the deep interior of the Earth. Their study enables Sea within the group of volcanic islands forming the processes occuring in the mantle, which are inaccessi- Baku archipelago. ble by any other method, to be understood. Major contributions to the first systematic stud- Magmatic volcanoes have a very close but al- ies of mud volcanoes were madeby researchers such most unknown relative, referred to variously as -mud as G.V.Abikh, V.A.Gorin, i.M.Gubkin, C.H.Gyumbei, voicanoes, sedimentary volcanoes, gas-oil volcanoes S.A.Kovalevsky, E.A.Shteber and others. etc. Mud volcanoes resemble magmatic voicanoes in In recent decades mud volcanoes have been that they erupt powerfully, with fiames reaching great thoro-ughiy studied by Azeri geologists: A.A.Yakubov, heights (several hundreds of metres), and they erupt Ya.A.Hajiyev, Ad.A.Aiiyev, A.I.Aiiyev, A.A.Alizade, millions of cubic metres of hydrocarbon gases and ton- Z.A.Buniatzade, F.G.Dadashev, F.A.Matanov, Sh.F. nes of mud onto the surface. Mud volcanoes at sea Mehtiyev, R.R.Rahmanov. S.G.Saiayev, M.M.Zeynaiov form islands and banks, altering the topography and and others. As a result we have today an abundance shape of the coastline, and causing local earthquakes. of scientific information on mud volcanoes. However There is one other feature of mud volcanoes this information, in contrast to that regarding magmatic which is of great interest not only to tourists, but also to volc'anoes, has hardly moved beyond the boundaries researchers. This is their direct relationship with oil and of the regions where mud voicanoes occur, and gas fields. Mud volcanoes resemble super-deep explo- therefore is not well-known by the reader from further ration wells, providing valuable information on the for- afield. mation and migration of oil and gas. This book,which is a first attempt to describe mud volcanoes in a form which is accessible to a wide

Acknowledgements - The autors are very grateful to the British Petroleum Company for the contribu- tion and popularization of mud volcanism, and flco to Graham Blackbourn for the translation of nhe original Russian text into E~glish. I. MUD VOLCANOES AND ZOROASTRISM Azerbaijan is exceptionally rich in surface gas seeps, some of which are alight (Fig.1). The gas flares which ac- k' -#?-:company the eruption of mud volcanoes are particularly impressive.

Fig.1. A burnlng gas seepage

- The burning flames have attracted people's attention slnce time immemorial, and they became an object of wor- m n - ship. This is shown by the numerous flre temples at Nush-Dzhan-Tepe. Adurgushnaep. Surakhany (Fig. 23), Pirallahi, Hovsany, Shakhdag and elsewhere. The h~storyof fire worship in Azerbaijan and the neighbouring regions of Iran has its roots deep in the past, at the beglnn~ngof the first m~lleniumA.D *

:, '. -.*-, i ,-k*,,.. r...... ,- -.. ;I - .zr I -. d

Fig.2. Zoroastrism in Azerbaijan: a) The Temp1 of the fire worshipers; b) The fire worshiper in the cell ALL ABOUT MUD VOLCANOES 3

The cult of fire worship was of paramount importance throughout the history of pre-Islamic Iran. The name of the first monarch of that country was Atrapata, which means "Protected by Fire". Fire worship played a particularly impor- tant role during the Sasanid period, when Zoroastrism was prevalent. The founder of Zoroastrism, Zaratushtra, is con- sidered by some scholars to have been born in Southern Azerbaijan. Zoroastrism continued to play an important role for three of four centuries even afler the Arabian conquest. Many examples of Zoroastrian literature date from this time. Great men of Azerbaijan such as Nizami, Khagani and Nasimi dedicated words of inspiration to Zoroastrism. And while Nizami and Khagani warned against fire worship, Nasimi glori- fied fire in almost every poem he wrote.

II. BUT WHAT ARE MUD VOLCANOES?

The greatest mud volcanoes in the world, Bolyuk Kyanizadag. Touragai , Bolyuk Kharamy and Kalmas, rise majestically above the surrounding landscape (Figs 3- 4).

Fig. 3. The Touragai mud volcano. The general view (airial photography after "Atlas ..., 1971). Fig. 4. The Boyuk Haramy mud volca-no.The gen- eral view (after "Atlas.... 1971).

Fig. 8.

The caldera at the summit of the volcano may be gently convex or shell-like in form, or consist of a deep de- pression (Figs. 10-12). The relative height and form of the slopes of a volcano's crater depend on its level of activity and on the nature of the material eru~ted. Fig. 10.The mud flow from caldera of volcano

- 1. :- A m R.. . L1

coldera of the mud volcano Fig. 12. The coldera of the mud volcano

Volcanoes whlch are not known for thelr powerful erupttons but are characterlsed by constant activity of gly- phons and salses do not usually form distinct topographic highs, and sometimes simply merge into the surrounding plaln (Figs. 13-15). Their highest points are usually raised by only 10-20 m, but they often cover an area several kilo- metres across. The craters are up to 400 m in diameter, and the base of the volcano 1s usully hyndreds of metres, and occa- sionally several kliometres, across. The area of the crater field in the largest volcanoes reaches 10 km2, and it is bounded by one or several concen- tric ramparts.

Fig. 13 1 ALL ABOUT MUD VOLCANOES 9

Fig. 14 I'

Fig. 15 Mud volcanoes are essentially instruments for taking gas and mineral waters, sometimes with traces of oil, to- gether with the associated mud (Figs.16-21), from great depths (8-12 km) (Fig. 22) and depositing them on the surface. During eruptions, angular blocks of rock of various ages and sometimes reaching several metres in diameter (Fig. 23) may also be expelled. They may be perfectly free of the surrounding argillaceous mater~ai,to which they are usuaiiy subordinate in volume.

Fig. 17. A1.L ABOUT MUD VOLCANOES 11

7-1

Fig. 18.

Fig. 19. Flg. 20.The mud flow with the oil films I

mud- gas bubble , ALL ABOUT MUD VOLCANOES 13 F

Fig. 22.A scheme of mud volcano. (after S.Kovalevsky)

Fig. 23.The blok of rock thrown away by the volcano during eruption The great bulk of the products of mud volcanism are erupted during periodic paroxysmal eruptions. Between these major events, deep material is extruded through domes, salses and gryphons. Domes (Figs. 24-25) are conical in form and up to 30 rn high, with a crater diameter of up to 10 m and up to 50 m across at the base; salses (Fig.26-28) take the from of lakes or pools,with poorly developed cones up to 1 rn high; and gryphons (Figs. 29-31) are essentially short conical domes, up to 0,5 rn high, and with a crater diameter from several centirnetres to 0,5 m.

Fig. 24.Mud volcanic dome

Fig. 25. Mud volcanic dome. . Fig. 26. The o~lsalses

ALL ABOUT MUD VOI.CANO~~ 17

Fig. 29. The glyphon

Fig.30. The gryphon againsta background of the breccia field Flows of mud-volcano breccia, together w~ththe crater field, are the main morphological elements of the topography of a mud volcano. Their form depends on the nature of the terrain, its slope, and the composition of the breccia. The length of mud-volcano flows reaches 2-3 km. They may be 200 m wide, and 8 m thick. The area covered by a mud volcano varies from 0.8-38 kmz (Figs. 32-33).

Fig.32.The breccia field of the mud volcano ALL ABOUT MUD VOLCANOES 19 , .

Flg.33.me breccla fleld of the mud volcano

After eruption the breccia undergoes rapid erosion, and the mud flows are reworked into a complex sys-tem of guileys and ridges, fanning-out from the crater margins. Mud volcanoes at sea form distinct islands, banks, and submarine mounds (Figs. 34-35).

Fig.34.The Garasu island mud volcano (After "Atlas...",1971) Fig.35.The Duvanny island mud volcano (After "Atlas...". 1971)

Ill. THE CAPRICIOUSNESS OF MUD VOLCANOES

3.1. MUD VOLCANOES -WHERE ARE YOU?

Mud volcanoes are natural phenomena which occur throughout the globe. They are found at a greater or lesser scale in Azerbaijan, Turkmenistan, Georgia, on the Kerch and Taman peninsulas, on Sakhalin Island, in West Kuban, Italy, Romania, Iran, Pakistan, India, Burma, China, Japan, Indonesia, Malaysia, New Zealand, Mexico, Colombia, Trinidad and Tobago, Venezuela and Ecuador (Fig. 36).

Fig.36Geographical position of mud volcanoes on the Earth: a-areas of mud volcanoes occurrence associated with hydrocarbon accumulations in deep-seated strata: l-North italy, 2-Sicily Island. 3-Albania, 4-Roumania, 5- Kerch and Taman peninsulas, 6-East Georgia. 7- south-east plunge of the Great Caucasus, 8-South Caspian. 9- South-west Turkmenistan, 10-Gorgan plain, lran, ll-Mokran sea coast, lran and Pakistan. 12-Belujistan, 13-Penjab province. 14-Hungaria. People's Republic of China, 15Assam province, India, 16-Burma. 17-Andaman and Nicobar Isls, 18- South Sakhalin, 19- Hokkaido Icland, 20-Taiwan Island, 21-Sumatra Island. 22Java Island. 23- Kalimantan island. 24- Sulawesi Island. 25- Timor Island, 26- New Guinea Island, 27-New Zaeland, 28- Mexiw. 29-Ecuador. 30-Colombia. 31-Venezuela, 32-Trinidad Island. (afler R.Rahmanov, 1987) : ALL ABOUT MUD VOLCANOES 21

Mud volcanoes are most well-developed in Eastern Azerbaijan, where more than 30% of ail the voicanoes in the world are concentrated (Fig. 37). More than 300 mud volcanoes have already been recognised here on land or at sea, 220 of which lie within an area of 16,000 km2. Many of these mud voicanoes are particularly large (up to 400 m high). The volcanoes of the South Caspian form permanent or temporary islands, and numerous submarine banks. Other regions where mud volcanoes are common include Colombia (50 volcanoes), Trinidad and Tobago (44), the Kerch (42) and Taman (41) peninsulas, Western Turkmenistan (25), Burma (20), ltidia (16) and Iran (15). Only one volcano is known in Mexico, and two in each of Ecuador and China. Up to ten volcanoes are known elsewhere.

Fig.37 The space map of mud volcanoes occurrence in.Azerbaijan.

Examination of the geographical

distribution and ' the geological and tectonic environments in which mud volcanoes occur shows that, although they are found 'throughout the world. they are mainly. associated with the Aipine-Himalayan and Pacific Ocean , mobile belts, i.e. zones in which I intense movements of the earth's surface have .been observed throughout recorde&history (Fig. 38).

Fig.38. Map of distribution of mud volcanoes on mobile belts. Mobile belts l-geosyncline and epi- geosyncline. 2-repeated orogenesis. 3-mid-oceann. 4-trans-form faults, 5-mud volcanoes occurrence regcons. (after R.Rahmanov, 1987)

However, they do not occur every-there throughout the mobile belts. Out of more than 170 hydrocarbon-bearing and prospective basins .within mobile belts, mud voicanoes have been noted in only 25. This is despite the fact.that anticlinal structures; faults, successions of plastic clays, gas accumulations, formation waters, and anomalously high pore pressures, which in the opinion of researchers are conducive to mud volcanism, are known in almost ail of the basins. It can therefore be concluded that the factors listed are insufficient for the formation of mud voicanoes. More detailed studies have indicated certain, km) has accumulated here over a very short period of mainly quantitative, amendments to the list of factors geological time, with argillaceous beds forming up to necessary for mud-volcano formation. Since it is 90% of the section. The beds are undercompacted, evident that the majority of mud volcanoes of the world and the clays retain their plasticity to great depths. are concentrated in the eastern part of Azerbaijan, then anomalously high formation pressures are widely an analysis of the distinctive characteristics of the developed, with an average coefficient of anomaly of geological' structure and development of this area 1.8. The vertical extent of the hydrocarbon-forming should determine the conditions necessary for the zone is extended from the usual 3-4 kilometres to 12 or onset of mud voicanism. more kilometres thick, and a very thick sedlmentary It must be recognised at once that such succession lies within the zone of Intense gas extensive mud volcanism in eastern Azerbaijan, whlch generation, which is of particular importance for the is tectonically related to the South Caspian Basin, does occurrence of mud volcanism. This continues to the not arise by chance. The development, modem present day, as demonstrated by the powerful geological structure and geodynamic conditions of this emissions of gas from great depths which are observed basin are unique even within mobile belts. This is during mud-volcano eruptions. reflected most clearly in the rapid subsidence and The occurrence here of active folding, the high sedimentation rates (up to 1000 mlmillion years , degree of deformation of the sediments, the compared to one or two hundred metreslmllilon years widespread faulting, and the high level of seismic in must of other basins with similar patterns of activity of the area should also be noted. development), the anomalously low heat flows (25-50 Ail of the above-mentioned factors reveal to mwlm2, compared with 41-109 m~/m~In other basins some degree the secret behind the unique in the Alpine mobile belt). As a result of these key phenomenon of mud volcanism, and demonstrate the factors, a thick sedimentary succession (more than 25 requirements for its onset and development.

3.2. 'AND WHAT'S YOUR NATIONAL NAME, VOLCANO? The most widely used name for this natural in-liquid clay), the names "mud lake", "bozdag" (grey phenomenon nowadays is "mud volcano". mountain) are used. The latter Is applied by the iocai Furthermore, where they vary in size, the larger types population to certain volcanic cones which rarely erupt, are known as mud volcanoes, and the smaller. mud and are covered by a sratlc mass of mud-lava whlch is cones. The term "salse" is applied to even smaller whitened by a salty efflorescence. The name varieties than "cones", and they usually emit only "akhtyrma" (whlte cover) Is used for a group of volcanic argillaceous material without solid blocks. Still smaller centres of the bozdag type whlch have blanketed a occurrences are often designated , diminutive wide area with their mud. Names of volcanoes expressions such as "mini-volcano", "mini-salse," and containing the suffix "-batan" may be encountered finally "mini-gryphon" or simply "gas vent". (from the word "batmag", meaning "stuck"). These Terms such as "volcanoid" (E.P.Shteber), "gas include Lok-batan, At-batan (i.e places where camels volcano" (S.A.Kovalevsky, 1940) or "gas-oil volcano" or horses become stuck), and may be used for an (V.A.Gorin and Z.A.Buniat-Zade, 1971) may also be extensive field of viscous mud breccia. The name found in the literature, together with "sedimentary "gainarja" (boiling place) is applied to gas gryphons volcano" (G.Kugler, 1934). In addition to these, local which vent into a liquid environment (mud, water or oil). names are used for mud volcanoes in different In Georgia, mud volcanoes are called "akhtaia". countries. These may emphasise one or another In Turkmenistan, in addition to the names aspect of their occurrence, or may relate to a particular already listed, the name "porsu-gel" (foaming lake, lake type of mud volcano. For example, in descriptions of of scum) is applied to mud-volcano mouths infilled by the mud volcanoes in the Kerch-Taman areas, in gasified turbid water, usually covered by a skin of mud. addition to the names listed above, local expressions The name "pat-laukh (mound, pile) is applied to piles such as "mud mountain", "burnt mountain", "peklo" of mud breccia on inactive volcanoes, such as: "Ak- ("scorching heat") and "blevak" ("puker") are used. Patlaukh" (white mound); "Gek-Patlaukh" (pale-blue A widespread local name for mud volcanoes in mound); and "Gyumyush-Patiaukh" (silver mound). On Azerbadan is "pll'pilya", or a term derived from it: the Kerch Peninsula the terms "peklo" and "puchina" 3, p~lp~lya.s , crater". In addition to the onomatopoeic "pil'- are used. pilya" (which reflects the sound of gas bubbles bursting ALL ABOUT MUD VOLCANOES 23

In Colombia, mud volcanoes bear the name in the Italian regions of Emilia and Campania. The "volcanitos"; in Trinidad and Tobago, (island od former corresponds to a gas gryphon expelling mud, Trinidad), "morn, buff and yard"; in Romania, "gloduor, and the latter to a "boiling" gryphon. In the south of flerb, fierbetor, boiboros, pykii, seretur"; in Malaysia, Sicily the name "makaluba" is used, and in the west. %gal", in indonesia, "pottos"; and In Venezuela, "salineila". Names such as "barbogll", "barboi", "e~ideros".The names "saise" and "boilitori" are used "spesso" and4'bombi"are also found in Italy. IV. THE LIFE OF MUD VOLCANOES - RESEARCH AND THE EVIDENCE OF EYE WITNESSES 4.1.HOW OFFEN DOES MUD VOLCANO WAKE UP?

The life of a mud volcano extends over a long geological interval, from Its Initial onset to its burial, and it may be subdivided Into active and extinct phases. The active phase of a mud volcano comprises repeafed,eruptions, between whlch they undergo gryphon-dome actlvity. Thls tendency for mud volcanoes to become dormant for a more-or-less extended perlod after major eruptions, and enter a gryphon-dome stage with greatly reduted activity, possibly with no signs of life, is a feature which Is shared with magmatic voicanoes. The maximum possible perlod of dormancy between eruptions varies from volcano to volcano, possible extending from 3-4 years (Lok-Batan) to 80-90 or more years (Bulla Island, Cape Alyat, Bozdag,etc.). In Eastern Azeraijan, around 50 voicanoes have erupted almost 200 times since 1810. The Lokbatan volcano has erupted the most times (19). The frequency of eruption of voicanoes in other areas is slgnlflcantiy less. In northern ltaly eruptions have been observed on only volcanoes (Sasaulo and Ren'yano), and the last paroxysmic eruption was as long ago as 1880. Major eruptions of six volcanoes have been recorded on the island of Trinidad. Several eruptions have been recorded of the Dzirdzhent volcano on Sicily island. In terms of frequency and strength of eruption the islands of Yan'be and Manun in Burmastand out amongst the mud volcanoes of the Bay of Bengal. The volcano of Dzhau-Tepe on the Kerch Peninsula has erupted five times during the present century. Twelve eruptions of the Karabetovsk volcano on the Taman Peninsula have been recorded. Studies of ancient mud-volcano activity show that they began to be active durlng the Early Miocene. Intense mud-volcano eruptions took place durlng the Middle Miocene (Chokrakian), Upper Miocene (Sarmatian), and the Pliocene and Pleistocene, until the present. Because of their unexpected nature and short duration, mud-volcano eruptions whlch take piace away from centres of population are not always observed from beginning to end. Descriptions of the complete cycle of the process of eruption are obtained from eyewitnesses (local inhabitants, shepherds, sailors, lighthouse keepers etc.). A considerable amount of information has been obtained in recent years by scientists undertaking specific studies of mud voicanoes (Figs. 39-42).

Flg.39.The Shykhzagirly mud volcano. The breccia filed afler eruption in September, 1992 (q) ~661Jaqol30 E pue (e) ~96~43~e~oz uo oueslon pnw letleg 40 uolldnla lave MOIJ pnw a41 '0~6!3 Fig.41 .The Bahar mud volcano. 2 weeks after eruption

Fig.42.The gas combustion on the mud volcano two weeks after eruption

According to the sum of such observations, eruptions begin suddenly with an dnderground roar or thunder-like crash, and after some time there is an eruption of gas and mud-volcano breccia composed of an argillaceous mass with rocks fragments from various stratigraphic ievels (Jurassic to Pliocene). These form tongues which flow down the slopes of the volcano. The gas then self-ignites.and forms a column of flame several hundred meters high (200-300 m, or in some cases up to 1000 m) (Fig. 43). The gas continues to burn for a variable period of time, and if the eruption happens at night it may illuminate a wide area. Eruptions can also take place without the gas igniting. One of the earliest recorded eruptions was that of the Gil adasi (Glinyanyi Island) volcano in the Caspian, which took place in 1810. Eruptions occuring over nistori-cal time can be distinguished ages of the breccia cover, which vary from each other i$ the nature of their erosion, colour, and vegetation (Fig. 44). - 7 ,. , - .- .-, . ,-.,,.,-:< - -- --

.oueqon pnw !~~!GezqyAysall1 uo suo~ldnlasnotwt, aalqijo sanfiuolmog pnw '~p'G!j 4.2 MUD-VOLCANO ERUPTIONS: ARE THEY SAFE?

The majority of active mud volcanoes lie away settlement of Khanagya, and overwhelmed an entire from centres of population, main routes and technical settlement known as "Old Gyady". A stream here often installations, many even lying on the Caspian Sea bed, washes out ancient implements, domestic articles and and they would not appear to belong to the category of coins. natural phenomena which can lead to disastrous An eruption of the Sangi-Mugan (Svinoi) Island consequences. However, cases are known where voicano on 11 April. 1932 had very tragic eruptions of mud volcanoes have resulted in material consequences. This eruption was preceded by that of damage, and even loss of life both to people and the voicano on the island of Chigil-deniz (Kumani), 12 livestock. miles from Sangi-Mugan Island, in October 1928. According to the local inhabitants the eruption of Sangi-Mugan island was inhabited by the lighthouse Bolshoi Bozdag, 88 km east-northeast of Shemakha, keeper, his colleagues and their families, and also by was such a case. It was sudden, powerful and brief. fishermen and their families. The emission of gas and The crater served as the usual overnight 'stop for its ignition were so sudden that the whole island was shepherds, since it contained a lake at which the sheep enveloped in flame in an instant, rising to a height of up were watered. On the night of the eruption about 2000 to 60 m. As a result of this fire, both living sheep and 6 shepherds had gathered there. The accommodation and outhouses were destroyed, and outbreak of gas occurred so rapidly that neither the the whole of the keeper's family perished, together with animals nor the shepherds had any chance to escape. family members of the other inhabitants of the island According to local legend a sud den powerful including 5 children from 2 to 7 years old. eruption occurred in the 15th century below the

V. GROWING MOUNTAINS

Geological processes operate very slowly and geologists usually measure them indirectly. Mud volcanoes present a unique opportunity not only to observe geological processes in action, but also to measure them quantitatively. Argillaceous material squeezed out of fissures in the crater, and forming large convexupwords ribbons of mud, is observed on many volcanoes. For example, on the Koturdag volcano in Azerbaijan no eruption has been recorded for a long time, but breccia as hard as plasticine is extruded from the crater like paste from a tube. he rate of movement and the amount of breccia squeezed out varies through time. The mass of mud moving from the crater down the volcano slopes resembles a tongue of a glacier, with its central parts moving more rapidly than the margins. Calculations made on the basis of 0b~e~ati0n~over intervals of 3.5 and 11 months show that the rate at which material is extruded in the central par! remains relatively constant, at about 3.5 m per month. An unusual mud volcano in the northwest Caucasus, Raznokol'sk, is characterised by material being squeezed out along distinctive mud "dykes" at a rate of 2.5-8 cm per day. Over a year, 1-5 to 10 m is extruded at a nonuniform rate (Fig. 45).

Fig.45.Sgueezing out dome breccia on the mud volcano Raznokolski(after S.Kovalevsky.1940). According to the peasents in the village of Derzhava near to Kerch, there is a small volcano close to their settlement which is slowly but steadily increasing in height, without the eruption of mud. The growth of volcanic cones without mud eruptions at the surface is very common, and in Azerbaijan they can be demonstrated clearly and simply by comparing the height of the growing structures with young Caspian terraces. According to S.A.Kovalevsky the moutain of Kyursangya rises each year by an average of 15 cm, due to the expansion of an intrusion at depth. In1970 the Azeri geologist F.A.Matanov became an eye-witness to the process of extrusion of plastic rocks onto the earth's surface. No one had previously observed this process, which took place on the West Cheildag volcano. Viscous plastic rocks were extruded through a horseshoe-shaped crack within the crater floor of the volcano. The extruded rocks were lifted to a height of 4-5 m, before collapsing along gently inclined surface. The width of the zone where rocks were being extruded onto the surface hardly varied from 80-95 m along its entire 300 m length. The zone was bounded on both sides by parallel fissures, 25-40 cm wide (Fig. 46).

Fig.46. Sgueezing out dome breccia on the Cheildag mud volcano (1970 year) After F.Matanov, 1981

The rate of extrusion of the rocks was at a maximum of 1.3 m per month during the entire three months of the eruption of the East Cheiidag volcano. The movement subsequently slowed. In 1971-1979 the rate of extrusion of rocks onto the earth's surface stabilised somewhat, varying from 2.2-2.9 m per year (Fig. 47). This extrusion of rocks continues to.the present day (Fig. 48). There are numerous other cases of breccia being squezzed under the cover of an old mud cone and the original rocks of the volcano slopes. This type of process usually occurs during an eruption of the volcano, leading to a rapid and sometimes substantial rise (up to 10 m) of mobile parts of the volcano over an area of several hectares. For example, during the eruption of the island volcano of Los in 1923, a marked uplift was noted of blocks of the Apsheronian beds above sea level. These formed part of the body of the volcano and had previously been below water. At the time of the fiery eruption of the Svinoi Island volcano in 1931 a 6-8 hectare area of the adjacent sea bed, consisting of old mud breccia, was raised to a height of up to 10 m. In 1932 an eruption of the offshore Byandovan volcano was accompanied by the, uplift of a part of the sea bed composed of mud breccia, which attached it to the coast. ALL ABOUT MUD VOLCANOFS 29

Eig.47. Rate diagram of sgueezing out plastic rocks on the 1 Cheildag mud volcano After F.Matanov, 1981

(Y I 1970 1975 1980 years

. . Fig.48 Sgueezing oyt clayly rocits on the C'he~ldagmud volcano (October, 1992):' .. . . -,. . . .~ 30 1.S.Guliyev , A.A.Feizullayev

Deep intrusions, forming mud laccoliths, protrude through the surface of the voicano, destroying its integrity. The vigorous growth of mud volcanoes, which has been observed repeatedly in Azerbaijan over recent years, the distinctive continuous emission of argillaceous materiai like the salt glaciers of Kukh- and Angura in southern iran. observed on the Koturdag and Raznokol'sk volcanoes, and finally the laccoliths discovered by N.S.Shatskiy ey al (1928) on Cheil'dag, represent a whole chain of occurences of mud volcanoes, each link of which is related to the remainder.

The major emissions of mud during. eruptions of mud volcanoes also play. . an important role the formation of mud-volcano cones. The length of the individual tongue-like flows of mud from high volcanoes can reach several kilometres (Fig. 49). For example, the southwestern flow on Otmanbozdag extends for 2.5-3 km. The width of the flow varies on the volcano slope from 100-200 m, and locally up i'o 500 m. The thickness varies from 5-6 m to 20 m, depending on the consistency of the mud (Fig. 50). These dimensions are controlled by the amount of materiai emitted during a single volcanic eruption, which can be very substantial. Ya. Shegren (1888), who was in Baku at the time of the Lok-Batan eruption of 1887, indicated that it had erupted around 200 thousand m3 of material; and the engineer Brinoli di Brunkof estimated that the eruption in 1835 of the smaller Sassuolo volcano near to Modena in Italy it had emitted up to 1.5 million mg of mud. The voiume erupted from the Keireki voicano in 1885 ws calculated by N. Barbot de Marni and S.Simanovich (1.891) as somewere around 350 thousand m3.Around 1 mlliion m3 of material was emitted from the Goreloi moutain in Taman at the time of its eruption. The sinking of numerous hand-dug wells on the surface of mud volcanoes in Azerbaijan has yielded interesting results. This was undertaken in order to determine the thickness of the material erupted, the nature of the underlying topography, the nature of the ground below the volcano, and the slze and nature of the eruption vent of the volcano. Twenty two volcanoes were studied, and it was found that the thickness of the breccia-cover varied on different volcanoes.from 40 to 110 m. The totai volume of material erupted varied from 0.21 km3(Lok-Batan) to 2.5 km3(Tashmardan). The volume of mud-volcano breccia erupted fom 220 mud volcanoes in Azerbaijan is estimated as 100-110 million m3. A comparison of the amount of materiai emitted during a single eruption of a voicano with its total volume may provide an indication of the palaeo-activity of the volcano. For example, the Touragai volcano erupted 50,000 m3 of breccia in 1947, and its totai voiume is 343 x 10' m3. if it is assumed that a similar amount of material is emitted during each eruption, then the formation of Touragai would have required more than 6000 eruptions. The totai voiume' of Boyuk Kanizadag is 735 x 10' m3, and 100,000 m3was emitted at the time of its last eruption. On this basis, it required more than 7000 eruptions to form. In 1954 the Tashmardan mud voicano emitted 2,000,000 m3 of breccia, and it has a :aiculations have shown that the formation of the Keireki mud volcano must ha- ALL ABOUT MUD VOLCANOES 31

Fig.50. Mud volcano. A fragment ot breccla held

VI. HOW DOES A MUD VOLCANO FORM? HYPOTHESES-AND MODELS

6.1 CAN A MUD VOLCANO BE MODELLED?

Although mud volcanism has been studied for more than a century, scientists continue to argue about the origin of this amazlng phenomenon. Some suggest that the process takes place wholly within the sedimentary succession, whereas others envisage a connection with deeper processes operating within the mantle. There is now abundant experimental and factual data on mud volcanism, together with the results of mathematical and physical modelling of previously proposed hypotheses,which have enabled them to established on a more scientific basis. According to modern theories, mud voicanism is typical of basins which are undergoing very rapid subsidence, so that the expulsion of pore fluids from the lowel levels does not keep pace with the rate of sediment accumulation. As result, part of the overburden pressure is exerted on the pore fluid, leading to an increase in the pore pressure gradient. This is particulary marked within argillaceous succession with low permeability. This process is responsible for the formation of mechanically unstable conditions within a succession of undercompactedargillaceous rocks. At a certain depth, where intense gas-generation (mainly methane) takes place due to the decomposition of buried organic matter, the instability of the system becomes yet more pronounced and reachs a critical condition. With a sufficient density contrast between the overlying and underlying deposits, and with the interaction of tectonic processes, the overlying deposits may loose their integrity and the underlying argillaceous sequence may be forced upwards, resulting in the creation of a piercement structure (clay diapir) or a mud volcano. Thls entire process can be confirmed on the basis of practical models. The photographs (Fig. 51) illustrate the different stages of this process as modelled in a tank filled with a sequence (from the base upwards) of compact clay, caicium carbide (mimicking deposits with a heigh hydrocarbon- generating potential), and a layer of sand to represent the overlying deposits. The photograph demonstrates that intense gas generation, resulting from the breakdown of calcium carbide, leads to the surrounding deposits being undercompacted, the overlying rocks being mecanically deformed with the emergence of faults and, the eruption of / underconsolidated material.

Fig.51. Stages of origin of mud volcanism on experimental models. l-water. Bsand, 3-calcium carbide, 4-cavity filled with hydrocarbon gases, 5-clay.

6.2 TECTONIC PLATES AND MUD VOLCANOES I

The well-known German meteorologist and geophysicist A.Wegener first proposed the hypothesis of horisontai. . continental drifl in 1912. The similarity, which had been noted many times in the past, of the coastlines of Europe and . I Africa on onk side of the Atlantic and North and South America on the other side led Wegener to form the idea that , 1 these continents represented the parts of a former whole, which had been separated by an expanse of ocean. . Wegener proposed that the mid-Atlantic ridge was the remains of the suture from which the continents had spread out the west and east. The fold belts of the American cordillera and the Andes were explained as having formed in the, frontal part of a continental block which was shifting westward. Further and more detailed studies showed that the mid-oceanic ridges were not simply systems of submarine ridges rising 3000-5000 m above the surrounding abyssal plains (with an average width of 1000 km), but that they were split along their longitudinal axis, and cut by a series of fractures which form gigantic graben systems 3000 m to 4000. rn deep and 20-40 km wide. The discovery of these grabens, which were called rifts, formed the basis for the American geologists and geophysicists Ditts and Hess,together with Vine and Matthews, to form the "spreading" hypothesis, i.e. the continual growth of ocean floor. The development of this hypothesis by Morgan and Mackenzie led in 1967-68 to: the concept of so-called "tectonic plates", according to which the earth's lithosphere is composed of a complex mosaic of "plates" which may be large 0; small in size, and bounded on one side by zones of rifting, and on the other by zones where oceanic lithosphere is being consumed (subduction zones) (Fig. 52). The edges of this plates are in tectonic terms the most active zones of the earth's crust, and are regions where the strongest earthquakes occur, where chains of volcanoes are found, where the crust is cut by deep faults, and the world's most substantial fold belts are formed. Virtually 99% of all earthquakes occur at plate boundaries (Fig. 53). 2

ALL ABOUT MUD VOLCANOES 33

Fig.52. Plate tectonics.The names of main plates are displayed on the map, small plates are marked by numbers: I-Philippinian plate; 2-Kokos plate; 3-Caribian plate; 4-Naska plate; 5-Arabian plate. Shaded sites of the map designate zones of deep earthguakes, arrows indicate directions of probable displacement of the plates (after D.Aiby. 1982)

Fig.53. Ep~centresof strong non-deep earthquakes over the period 1904-1952 years. 1-M7 -7,7; 2-M7,8 and more (after D.Aiby, 1982)

Analysis of the distrubution of magmatic and mud volcanoes of the world shows that, just as with earthquakes, they mainly lie along narrow tectonically active zones. As with plate boundaries they are also divided into two main groups: volcanoes of subduction zones and volcanoes of rift zones (Fig. 54-55). Fig.54. Scheme of igneous volcanoes occurrence on the Earth. I igneous volcanoes occurrence zones; I1 subduction zones; Ill spreading zones IV plate movement directions. (after Sh.Mehtiyev, E.Khaiiiov, 1984)

Fig.55. Scheme of occurrence of mud volcanoes and subduction zones. 1- zones complicated by mud volcanism; 2 - sybduction zones; (after Sh.Mehtiyev. E.Khalilov. 1984)

In contrast to the voica- nism of rift zones, which is mainly concealed below deep water, the - volcanism at sub-duction zones is mr more impressive since it often I---;Ip occurs in the densely populated 0 ....rk-n- IT :margins of continents and adjacent 2 8 island groups. Only too oflen in historical times it has interfered with the daily life of the inhabitants of these islands, someimes with tragic consequences, causing material damage and taking numerous lives. An analysis of the spatial distrubution of the mud volcanoes of the Caucasus-Kopetdag region by Azeri geologists has shown that they lie within a subduction zone (Fig. 56). The authors consider that this is not just a coincidence, but that it is explained by the fact that subduction zones contain all of the features necessary and sufficient for the formation of mud volcanoes: a great thickness of sediments, intense folding, zones of anomalously high pore pressure, deep faults, and substantial tectonic activity. A great thickness of sediments, intense folding and the presence of anomalously high pore pressures is associated with the scraping off and compression of sediments being carried down into the Benioff zone of a lithospheric plate, and accumulating in a deep-water trench. ALL ABOUT MUD VOLCANOES 35

Fig.56. Scheme of occurrence of deep-focus earthquake epicentres and mud volcanoes of the Caucasus-Kopetdag region. i deep-focus earthquake epicentres; II zone of deep-focus earthquakes; Ill mud volcanoes; IV zone of mud volcanic manifestations (after Sh.Mehtiyev, E.Khalilov, 1984)

6.3 EARTHQUAKES: HANDS OFF THE VOLCANO!

Ever since the Earth was formed there has periodically been the accumulation of energy at depth, and then its release. The maximum release of accumulated energy occurs with earthquakes, magmatic eruptions and mud volcanoes. There must be some interrelationship between these natural phenomena, and such a relationship has recently been established. In particular, a statistical analysis of the distrubution of earthquakes and mud-volcano eruptions in Azerbaijan by month from 1810 until the present day has shown that earthquake activity leads to mud-volcano eruption, and that earthquakes precede mud volcanism (Fig. 57).

Fig.57. Distrubution curves of eathquakes, 1669-1982 years (I), and mud volcanoes eruptions, 1987-1972 years (2) in Azerbaihan on months. (3) -curve (2) shifted to right by 1.7 months. This is explained by the fact that the energy of seen from far off. After about three days the column an earthquake far exceeds that of a mud-volcano changed to a low flame above the mud dome. eruption, and is a definite factor in the release of The sensitivity of mud volcanoes to seismic energy from underground. The seismic activation at shocks has been observed not only in Azerbaijan but depth of one volcano, by movement on regional faults also in Turkmenistan and Sakhalin island.ln June 1985 and fractures and the increase in the supply of gases to the captains of several ships reported the first 7 the eruptive apparatus, serves as a means to pump emergence above sea level, to form an island, of the '' energy Into others which are in the critical metastable usually deepwater Livanova Bank, which corresponds condition necessary for eruption, and fulfills the role of with a major mud volcano within the Turkmenistan - a trigger effect. The eruption of two major mud sector of the Caspian Sea. This coincided with the voicanoes (Boyuk Maraza and Boyuk Bozdag) serves destruction of the town of Turkmen-Bashy (Krasno- as an illustration of this. They lie on the longitudinal < vodsk) at the time of the Uzunadinsk earthquake. axis of the destructive earthquake which occured inShemakha on 31 January 1902. The eruption of the Earthquakes therefore serve as triggers for the ;-,: Boyuk Maraza volcano occurred about 10-15 minutes eruption of mud volcanoes, and at the same time the - , after the subterranean tremor. it initially took the form volcanic eruptions iead to local tremors which affect the b of puffs of black smoke up to 80 m high which changed surrounding area, i.e. there are volcanic earthquakes. in the upper layers of the atmosphere into clouds, and A.A.Yakubov, F.T.Guliyev and T.A.lsmail-Zade first gradually disappeared. After some time there was a determined the energetic class (K) of such an qulte perceptible movement of the earth, after which earthquake at the time of the eruption of the Lok-Batan there appeared a column of burning gas. The column mud volcano on 1 October 1972. It measured an quivered, first increasing in he~ght,then decreasing to a average of 8.9, which corresponds to the energy of a height of not less than 20 m. It shown at night and was weak earthquake.

6.4. MUD AND MAGMATIC VOLCANOES: SiMllARiTY OR RELATIONSHIP?

One of the first who drew attention to the similarity between mud and magmatic voicanoes in tenth century was well-known tenth century Arabian traveller, geographer and historian Masudi, who described an eruption of one of the volcanoes in the Caspian Sea as follows: "Opposite this (Baku) coast lie islands in the sea; and on one which is three- day's journey rising to the sky as the highest mountains, and it emits fire greater than the size of this sea, so that it is visible from a distance of almost 100 farsakhs (-700 km) from the shore. This volcano can be compared with the volcano of Burkan (Etna) in Sicily, in the land of the Franks". Certainly in terms of its outer form, the structure of the eruptive apparatus and the nature of its activity a mud volcano has the same features as a magmatic volcano: it has a similiar cross-section to its volcanic cone, with a crater and caldera, a crater rampart which is breached at times In various directions by flows of the volcano's liquid products, and with tongues of the latter flowing out, etc. (Fig. 58-60). it is true that mud-volcano cones are very much lower than those of their magmatic cousins: they reach 500-600 m at the very highest. However it is impossible here not a consider the fact that the material which is exuded from mud volcano-es and which moulds their slopes, mud, is readily eroded and removed by the activity of exterior factors. I r' ALL ABOUT MUD VOLCANOES 37

Fig.58.The mud(a)and magmatic (b) (after V.Aprodov) volcanoes

I Fig.59 a)The general view at the magmatic volcano (a) (after V.Apro- dov) and mud vol- cano(b) , Q cpT~ig.60. The general view at the islands mud (a) (after Atlas .... 1971) and magmatic@)(after H.Rast) volcanoes. -1. . - Mud volcanoes are also worthy rivals of magmatic volcanoes in terms of the scale of their eruptions (Fig. 61), and their catastrophic consequences. For example, the mushroom cloud which resulted from the eruption of the Otmanbozdag volcano, not far from Baku, in January 1922 was visible over hundreds kilometres, and reached a height of 1.4 km. But is this similarity the result of a genetik link? One of the first researchers into mud volcanoes of the Caucasus, G.Abikh, studied a piece of breccia from the mud-volcano island of Chigil deniz (Kumani) in 1860. He established its chemical and petrographic identity with volcanic rocks of the trachytic series, and on the basis of this came to the conclusion that the mud breccia was a mixture of two different components: magmatic material derived from deep in the volcano, and sedimentary-rock material from below the volcano which it had captured on the way to the surface. Mixed and greatly altered by hydrochemical processes occuring within the volcanic chambers, these rocks also comprised mud lava or breccia from mud volcanoes. ALL ABOUT MUD VOLCAZIOES 39

Fig.61 Eruptions of ~gnous(a) and mud (ti) by Ad Alyev volcanoes

He did not doubt the link between "real" and mud volcanoes, and S.A.Kovalevsky 1940 considered that "the relationship between mud volcanism and volcanik activity is like that between the flames of a fire and the boiling of a saucepan". In other words, at the centre of a

. underground magmatic chamber. Supporters of this view resort first of all to the salses of Sicily: "makalubi" (from the Arabian word "maklub, meaning "destroyer"), which are developed on the slopes of Etna. Eruptions of mud often coincide with eruptions of lava. The mud itself, a mixture of water and silt, is often hot. The composition of the gases is also largely "volcanic". Furthermore, the further one moves from the magma!ic volcano, the cooler is the mud emitted from salse craters, and the gases differ increasingly from the "mother" gases of Etna. But what is the situation with the mud volcanoes However, the mistake of Abikh and his of Caucasus, which develop in a region where successors had been pointed out as early as 1871 by magmatic gases are absent, and where the mud and his worthy Bavarian contemporary, Karl Humbel, after gases emitted are usually cold, and the gas studying pieces of mud breccia from Bulla Island and composition is pure methane? In the opinion of Kumani Bank, received from Abikh in Vienna. Since S.A.Kovalevsky there are magmatic eruptions here as then abundance of information has been gathered, and well, but they occur underground. Lavas forcefully today it is difficult to find any geologist who would invade water-bearing sedimentary horizons confirm that mud and magmatic volcanoes have the underground, and on account of the abrupt fall in same origln. This is to a large degree due to studies of pressure and temperature they break them up, mixing the isotopic composition of helium, carbon in methane, with the water. But the volcanic gases, which change and argon from mud volcanoes which, as a rule, show their composition due the chemical reactions with that they are of sedimentary origin. Some mud organic and oil products, drive the resulting mud volcanoes (such as Akhtaia in Georgia) do, however, through faults in the earth's crust to the surface. This containa small proportion of gases of deep origin. results in a mud-volcano eruption. VII. THE BREATH OF MUD VOLCANOES Numerous attempts .have periods of quiescence the flows during eruptions of ,all of the been made to evaluate both from individual volcanoes varied volcanoes of Azerbaijan is around experimentally and mathema- from 0.1 m3/year (Pil'pilya) to 731 250 million m3, and that the total ticaiiy the volumes of the products m4year (Akhtarma). volume of gases emitted since the of mud-voicano activity (gas, The total annual volume of beginning of the Quaternary is breccia, water) which are emitted gas emitted by all of the 175 x 10%iiiion m3. on the earth's surface at the volcanoes of Azerbaijan is about The amount of water present day. 20 million m3/year. emitted by mud volcanoes is The gases given off by mud A certain amoune of gas negligible, varying from 0.01 to 12 volcanoes are one of the main (about 2 cm3 per kg of rock) is m3/day.Amongst the volcanoes of factors behind their activity, and also given off due to degassing of Azerbaijan the most water emitted therefore a quantitative evaluation the breccia. from the Matrasa and Nabursk of gases emitted may provide However, the greatest volu- salses and gryphons (9-12 important information of the me of gas is given off during m3/day). The volcanoes of the motive force behind these paroxysmic eruptions of volcano- Alyat ridge are also water-rich, distinctive natural occurences. es. According to assessments including Dashmardan, Durandag, According to available made of the basis of duration of Koturdag and Bakhar. A total of measurements on tens of mud combustion and the height of up to 20 m3/day of water is given volcanoes in Azerbaijan during flames during eruption, hundreds off by these volcanoes. Measur- their quiescent periods, the flow of of millions of cubic meters of gas ements of 53 volcanoes in Azer- gas varies widely. For example, are emitted over several hours. baijan give a total daily flow from within a vast crater of mud in the For example, during .of the them of around 73 m3/day. Dashgil' volcano the flow of gas reuption of the Touragai mud Extrapolating this figure to all of reached 40 thousand m3 per day. volcano in 1946, about 500 million the active volcanoes of Azerbaijan At a second reading 13 months m3 was emitted, and about 65 (excluding those at sea) indicates later, the flow was just 8 thousand million m3 from the Duvannyi that the total flow of water from m3 per day, and then after another Island volcano in 1961. The them must be about 200 m3/day, 12 months it had fallen to 200 m3. Bolshoi Maraza volcano erupted or 730 billion m3/year. The volcano then began to for 3 days in 1902 and emitted A substantial amourrt of increase its flow of gas again. The 120 million m3 of gas into the water is emitted as a component figure for the average daily flow of atmosphere. of the breccia during eruptions. It gas on Dashgii' is now about 20 From 1810 until the present has been calculated that the thousand m3. day, about 250 eruptions of 60 amount of water given off by the Measurements made by volcanoes have been observed in volcanoes of Azerbaijan during F.G.Dadashev on 242 vents from Azerbaijan. It is calculated that their eruptions is around 24 km3. 21 volcanoes showed that during the annual volume of gas emitted 1 A1.L ABOUT MUD VOLCANOES 41

Specialised techniques flow in the vicinity of a mud voi- red due to the firing of the argii- have been used to measure the cano is increased. iaceous groundmass of the brec- effect of mud volcanoes on the Professor S.A.Kovalevsky cia (Fig. 62-63). The surface of geothermal conditions at depth. obtained an interesting picture of the breccia on the crater floor is The eruptive apparatus of mud the temperature regime of Lok- cut by fractures, from which volcanoes include distinctive Batan, the most active mud vol- scorching gases and water va- channels along which heat is cano in Azerbaijan, during a geo- pour are emitted. The tempem- transferred from depth to the sur- logical excursion in 1924. He ture of the rocks over the entire face more intensely. This is clear wrote: "In a depression in the crater is such that, on walking from the constant thermal anoma- crater of the mud volcano, at its over it, the feet are scorched lies which coincide with the parts eastern wall, pale-biue smoke through the soles of the boots; of structures which are affected from a hot gaseous emissions is and pieces of rock broken off from by mud volcanoes. The difference perceived. The floor and wails of the blocks touched by the hot jet in temperature between the area the crater at the location of the of gas must be lefl for haif-an- of mud volcano and that beyond vent of hot gas are coloured a hour before they can be held in its limits reaches 3-5%. The heat mottled violet-grey, pale-plnk and the hand without burning".

Fig.62. Gas combustion source and a fired rocks on the Bahar mud volcano

Fig.63. The rocks fired due to gas inflammation with eruption of mud volcano. At the time of a second excursion to the volcano exactly two years later, everything remained as described, although on a significantly smaller scale than previously. The temperature of the rock surface by the burning gas was this time only 130'~. The temperatures of the gases emitted from powerful gryphons after eruption have been measured very rarely. D.B.Golubyatnikov measured the temperature of a gas stream in one volcano after eruption at about 50' C. Approximtely the same temperature was recorded five days after epurtion of the Otmanbozdag volcano in Azerbaijan. The temoerature of the liauid mud in the crater of the Touragai volcano six days after its eruption was comparable (437. In the Keim~rvolcano of Turkmenistan the temperature of the emissions measured in the main crater was 43' C, whereas the temperature of waters in the surrounding lakes of secondary craters was only 27' C. Therefore, the temperature anomal~esin the region of mud volcanoes are the result of the movements of hot flu~dsalong their eruption channels. VIII. MUD VOLCANOES IN THE "EMBRACE" OF THE COSMOS 1 8.1. MOON AND SUN PROVOKE VOLCANOES.

In 1923 an unusual communication in a scientific journal attracted the attention of volcanologists around the f world. In it, the volcanologist F.A.Peret calculated the mutual positions of the moon, sun and earth, and predicted an abrupt increase in the volcanic activity of Etna on 27 July. Specialists were sceptical about this communication, since according to data from direct obser-vations of the volcanic crater its activity was clearly decreasing. However on 27 July, when a maximum lunar-soiar tide was observed, the silent crater let out a roar, and a black cloud covered its summit. After this scientists began to retrace the records and to discover that there is some general relationship between volcanic activity and cosmic processes. According to current theory, mud volcanoes with smaller mud and gas systems will be more sensitive to changes in the surrounding environment, and therefore more likely targets for a relationhip between processes deep in the earth and cosmic processes. Specialist studies undertaken in recent years have to a certain extent confirmed this theory. At present the most well substa-tiated and relatively reliable finding relates to the influence of lunar and solar tides on mud-volcano activity. Gravitational effects on the earth are most perceptible when the moon is at ist perigee (its closest approach to the earth), or it lies on a direct line with the earth and the sun (at times of solar and lunar eclipses). The influences the rotation of the earth and leads to fluctuations in its surface layers, which often provide the additional forces required to release the internal energy which hase built up at the seat of volcanoes. In 1955, scientists from Azerbaijan studied statistics documenting 150-years of eruptions of mud volcanoes in the Caucasus, together with astronomical tables of the mutual positions of the moon, earth and sun over the same period. This showed that around 60% of all eruptions (out of a total of 200) occured at the time of the new moon or full moon. On the basis of this, a forecast was made of mud-volcano activity over the next four years. The forecast was fully confirmed: nine major eruptions during the period 1957-1960 occured precisely at the times predicted (Fig. 64).

1 2 3 5 6 78 9 a 0 e Fig.64. Predicted by astronomic calendar (A) and realized (5) eruptions of mud volcanoes: a - large, b - middle eruptions.

1957 1958 1959 1960 years LL ABOUT MUD VOLCANOES 43

At the time of the total solar eclipse of 31 July 1981, which was observed over a substantial part of the eurasian continent, special obse~ati0nSof mud volcanoes in Azerbaijan and Turkmenistan noted a significant increase in their activity. The flow of gases increased, some extinct cones were reactivated, and new gas microvents opened. Following the idea of the well-known English astronomer S.Mitton, that "the heavenly body which exerts the greatest influence on the earth is the sun", attempts were made to explain the activation of volcanoes by the sun. This resulted in the conclusion that periods of increased solar activity correspond to periods of increased mud-volcano activity around the world. On the basis of specialist observations on the activity of the Akhtala mud volcano In Georgia, a quite reliable relationship was established between its activity, and both the magnitude of solar activity, and its variability through.. time (Fig. 65). Jv

Fig.65. Comparison of activity of the Akhtaia mud volcano with solar activity. Y -volcano gryphons discharge smoothed on 4 decades, Ys -Vulf indicies (solar activity) smoothed on 4 decades I- (after V.Valvayev et al, 1980) ' ~ciknmc2nd technical progress in the second half of present century ginerated an opportunity to study the structure of the Earth from the far kosmos. Therefore we can have an idea today about the mud volcanoes looking from the kosmos. According to these explorations not just mud volcanoes but also dynamics of their activity can be clearly well- defined from the kosmos.(Fig.66) I 8.2. THE SEARCH FOR RHYTHMS IN THE VENTING OF VOLCANOES

Rhythmicity is one of the clearest and most thousands, millions, or even billions of years, is widespread characteristics of natural systems. It is associated with geological events. observed in virtually all processes, both of organic and Experimental observations and Fourier analysis inorganic origin. Light, sound, waves at sea, ocean of the accumulated data established that mud tides, the succession of days and nights, the alternation volcanism is not devoid of any rhythmicity. of the seasons, cyclicity of geological processes, Variations in the flow of gas from the Dashgil' rhythms of solar activity etc.; these are all different volcano of Azerbaijan depend on the time of day, with forms of oscillation. Together with the shortest-period the flow increasing at night and decreasing during the oscillations which are found in the world of day. microphysics, measured in thousandths or millionths of Laser measurements above a methane vent on a second, oscillations occur in nature which the ~strakhanka mud volcano in Azerbaijan have encompass a very wide range: seconds, minutes, reveated a high-frequency oscillation with a period from hours, days, seasons, years and centuries. Cyclicity on several to a few tens of minutes (Fig. 67). a global scale, with frequencies measured in

Fig.67. Characteristics of methane outflow from mouth of the Astrakhanka mud volcano on the data of laser measurements.

The established relationship between the cosmos and the earth is also shown by the fact that in many naturai phenomena, and particularly in the activity of mud volcanoes, rhythmsare found which are characteristic of certain cosmic processes. Out of.all the cosmic rhythms which affect the earth, the strongest is the fluctuation in solar radiation, which has a period of about 11 years. In order to search for such periodicity in the activity of mud volcanoes, the changes through time in the activity of about 300 volcanoes from around the world were analysed. This resulted in the discovery of a 9-12 year periodicity in mud-volcano activity, which mainly coincides with the 11-year cyclicity of solar activity (Fig. 67).

" Fig.68. Comparison of solar and mud volcanic activity plots: 1 - mud volcanic activity plot; 2 -solar activity plot (Vulf numbers). (after Sh.Mehtiyev, E.Khalilov.1988) , , ALL ABOUT MUD VOLCANOES 45

An II-year periodicity was also established for the fiuctuations in the eruption of mud from the Akhtala volcano in Georgia (see Fig. 65). According to the retrospective analysis of data from mud voicanoes in Azerbaijan, rhythmic activity can be established not oniy through time, but also spatially. A change in the cycles of activity can be distinguished in passing from northwest to southeast.( V.Gorin and Z.Bunyat-Zade, 1971).

IX. THE MUD VOLCANO AS AN INDICATOR OF DEEP HYDROCARBONS

Virtually all the geologists in the world now 100%) of methane, must be the lower zone of intense recognise that mud voicanoes (of the type which emit gas formation. This Is clearly confirmed by the very hydrocarbon gases) are direct surface indicators of interesting observations on the Lok-Batan oil field and hydrocarbons at depth in the regions where they occur. the mud volcano of the same name. It was noted here However, for a long time, some specialists thought that that rapid development of the oil field had no affect areas affected by volcanism were economically non- whatsoever on mud-volcano activity: it continued to prospective, since they considered that the mud erupted as before at intervals typically of 3-3.5 years. volcanoes caused oil and gas accumulations deep in And in contrast, the accumulation by the volcano of a the earth to be destroyed. Although there is connection huge volume of compressed gases, measuring around between mud volcanoes and hydrocarbons at depth, It 26 million cubic metres, and its instantaneous eruption should be recognised that the connection is not simple. into the atmosphere, had virtually no effect on the flow Mud volcanoes are certainly not just "naturai wells" from the nearby wells. drilled by nature itself through gas and oil fields. Both In other words, the massive oil field with colossal mud volcanoes and hydrocarbon fields are the gas pressure, which at the start of production from the outcome of different stages of a single process of oil upper horizons (at depths of around 2 km) flowed up to and gas formation, which has a characteristic vertical 20 thousand tonnes of oil per day, showed itself to be zonation. This zonation, which was worked out for the almost entirely sealed off from its deeper levels, even first time by N.B.Vassoevich in 1948, is based on the during eruption of the volcano. At the same time, sedimentary-migrational (biogenic) origin of methane from the zone of intense gas formation at a hydrocarbons.According to this zonation oniy gases considerable depth (8-10 km) was forced up to the form initially in the upper layers of the earth (with surface, which it reached with regular powerful methane as the main hydrocarbon), and then as the eruptions. rock is buried it may be abserved a zone of intense Therefore the connection between mud formation of oil and fatty gases (homologues of volcanoes and hydrocarbon fields lies in the fact that methane), and finally, more deeper, the zone of oil the hydrocarbons in them both are the products of a formation gives way to a zone of intense gas (methane) single process of hydrocarbon formation within the formation. sedimentary succession. The clear evidence of this is Therefore the source of the hydrocarbon gases that structures cut by mud voicanoes contain, as a rule, in mud volcanoes, which are composed mainly (95- economic hydrocarbons.

X. THE MOUTH OF MUD VOLCANOES: LABORATORIES FOR GAS-HYDRATE SYNTHESIS

On 19 March 1969, the scientific discovery of a previously unknown property of natural gases formed within the earth's crust was registered with the State Committee of the fomer USSR for Discoveries and Inventions: under certain thermodynamic conditions the gases form accumulations in a solid gashydrate state. The formation and accumulation of gas hydrates on land is associated with the upper part of the sedimentary cover within permafrost zones (in sub-zero temperatures). Gashydrates may form within the world ocean in conditions of low temperature and high pressure. It is considered that the present thermodynamic conditions of the earths' sedimentary cover over about 25% of the iahd and 90% of the marine basins correspond to conditions where naturai gases can accumulate and be preserved in the solid hydrate form. Thermodynamic conditions are favourable for hydrate formation within the Caspian Sea. In addition, an important factor in the formation of accumulations of hydrates of hydrocarbon gases is the widespread deve-lopment within the Southern Caspian of mud volcanism, which is the supplier of vast quantities of such gases. The mouths of some volcanoes may, it was thought, form highly favourable sites for the formation of gas- hydrates. Special exploration work undertaken at the end of the 70's confirmed this theory: the first gas- hydrates were discovered within the breccia from one of the volcanoes. More intense studies carried out here in 1986-88 discovered a zone of gashydrate formation on the Vezirov (Shatsk Arch) and Azizbekov uplifts, and convincing signs of the presence of gashydrates were found on one of the uplifts of the Abikh Arch. In terms of chemical composition the gashydrates were methanic (62-76%), with 21-28% in total of methane homoiogues, and 1.2-7.9% CO,. Nitrogen, hydrogen sulphide, hydrogen and helium were found in trace amounts. Isotopically the carbon in methane from the gashydrates was identical to that in the gases of the hydrocarbon fields of the region.

XI. MUD VOLCANOES: SOURCES OF VALUABLE RAW MATERIALS

11.1 MUD VOLCANOES GIVE BIRTH TO MINERALS

The world minerals associated with mud volcanism is astonishingly varied. So far, more than 100 mineral species have been described, the majority of which are derived from the reworked rocks erupted from mud volcanoes. Of particular interest is the small group of mineral species which are genetically related to the processes of mud volcanism. Minerals of mudvolcanic origin reflect the complex multi-stage physico-chemical processes which take place as the volcanic waters and gases interact with the surrounding iithological succession penetrated by the mud volcano. The most widespread mineral is pyrite, which is particularly characteristic of the volcanoes of Azerbaijan and the Kerch-Taman area. Perfectly fresh aggregates of pyrite are very often found within the material erupted, either in the form of crystalline incrustations on various solid rock fragments within the volcanic breccia, or as beautifully formed crystals, dispersed throughout the argillaceous groundmass (Figs. 69-70).

Fig.69.A rock with mineral inclusions thrown out by mud volcano *

ALL ABOUT MUD VOLCANOES 47

Fig. 70. The minerals in breccia of the Kerch-Taman mud volcanoes (after"Atlas. .". 1986)

ALL ABOUT MUD VOLCANOES 49

The largest pyrite crystals (up to 10 cm) have been found in fresh volcanic breccia from the Boishoi Maraza mud volcano. The following minerals of mud-volcanic origin have also been recognised: native graphite; suiphides - cinnabar, sphaierite, wurtzite, molybde-nite, galena, realgar, orpiment; suiphosalts - dufrenoysite; oxides - cuprite; carbonates - malachite; sulphates - barite, hexahydrite; borates - iuneburgite, boropatrocalene and others; halides - fluorite; phosphates - apatite, dehrnite, complex Iron, magnesium and calcium phosphates. ' Minerals originating from mud-volcano activity are distinguished by their complete absence of rounding, their iddelicate and thin form, and the common occurrence of fragile crystalline growths. There is similarity between the assemblage of minerals of mud-volcano origin and that which is typical of low- temperature hydrothermal processes.

11.2 VOLCANIC BRECCIA: A VALUABLE NON-ORE NATURAL RESOURCE

An extensive range of geological and technoiogicai studies undertaken over virtually all of the major mud-crater fields on the Kerch Peninsula showed that the breccia is siutable for the production of ceramzite, one of the most modern building materials. It is light, durable, and low in cost. Ceramzite is a wonderful heat- and sound-insulating material. Materials favourabie for ceramzite production are fresh dark-grey and grey clay breccias containing minimal amounts of coarse fragments, sand and silt. At present the dark-grey clays from the Malo-Babchinsk crater field are used as a raw material for high quality ceramzite. Considering the extensive development of breccia deposits on the Kerch Peninsula, their considerable thickness, their good geological and technoiogicai characteristics, and their proximity to production facilities and consumers, this region and other areas of mud-volcano development may be considered as having a high potentiai for the provision of raw materials for the manufacture of ceramzite. Preliminary testing of breccias from several mud volcanoes has shown that they may be used as an additive in the capacity of a metallurgical flux instead of bentonitic clays. Dolomitised limestones, sands and clays from mud voicanoes are used extensively for building roads and surfaces. For example there has for a long time been a quarry within the Voskhodovsk mud volcano on the Kerch Peninsula. Building materials are extracted from mud voicanoes at quiie a substantial rate. On the Kerch Peninsula, 80 thousand m3 are extracted each year from Sarmatian bryozoan limestones below the Burul mud-volcanic mountain, 260 thousand tonnes of clay are taken from the Malo-Babchinsk quarry, and 52 thousand tonnes of clays from below the Voskhodovsk crater field. Geologists in Azerbaijan recently drew attention to the potentiai for using the solid eruption products of mud voicanoes as a cement. Their suitability results from the well-dispersed nature of the component minerals, and the presence of amorphous siiicia, SiOl (glass), and lime (CaO). These properties of the mud mean that basic techology with a low energy consumption could be used to manufacture articles such as bricks, including those not needing to be fired. With the oxidation of siderites within the clays both on the surface and along cracks, accumulations of secondary iron hydroxides coloured bright yellow, crimson, orange and red form. These ochres may be used as the raw materials for mineral dyes. Friable accumulations of the secondary iron sulphate jarosite, coioured bright yellow, could also be used for the same purpose. The clay from mud volcanoes is used widely as a simple abrasive cleaning material.

11.3 MUD VOLCANOES CURE PEOPLE

At the present day preparations of mud, obtained mainly from silt deposits, peatbog or sapropelic muds, are used extensively around the world for curative purposes in the form of injections, baths, washes, compresses etc. From this viewpoint attention has been directed at the eruption products of mud voicanoes, and particularly the solutions from mud domes, which contain both inorganic and organic components. The solutions from volcanic mud appears as a transparent liquid with yellowish colouration, odouriess, and salty to the taste. The mineral content of the solution from mud volcanoes compared with that from silt deposits (150-350 gll) is low (10-40 gll). Chemically the volcanic mud is composed mainly of silicia (55-70%). In addition, the mud has been found to be high in ingredients with curative properties: iodine, bromine, calcium, magnesium, sodium, chlorine, lithium, iron, selenium, manganese, zinc etc. Spectral analysis on the volcanic mud has discovered small quantities of humic and fulvic acids, naphthenic acids, tars, asphaitenes, methanic, naphthenic and aromatic hydrocarbons, oils etc. In terms of its organic content, volcanic mud has a certain similarity with that of mud from silt deposits, and the curative naphthalenic oils. Experimental studies on animals indicate that toxic substances are absent from the volcanic mud. In addition, the results of these experiments show that the mud solution may be recommended as a new form of mud preparation, used in electrophoresis for curing various diseases: diseases of the joints and vertebrae, osteochondrosis, diseases of the peripheral nerves, initial forms of atherosclerosis and hypertonic disease; gyna-ecological diseases etc. At the present time the mud from the Bulganaksk crater field is used in the curative towns of Feodosia and Kerch. The history of using volcanic mud began here in the 30's. Therefore, regions where mud volcanoes are developed may in the future become part of an extensive network of mud clinics.

XII. THE MUD VOLCANO: A UNIQUE MONUMENT TO NATURE

Mud volcanoes are unique natural phenomena distinguished by their unusual "lunar" landscapes, their distinctive splendour, their continuous gentle activity, and rare but awesome catastrophic eruptions accompanied by huge flames. A considerate approach towards this natural phenomenon, involving the preservation of mud-volcano landscapes for future generations in their original form, is a real problem. This isparticularly important in view of the numerous cases where. gryphons have been filled with rubbish, where steppe volcanoes have been used as burial grounds for cattle of scrap heaps, and where volcanic breccia has been used without any controls as a building material or a chemical resource (Fig. 71). This type. of activity not only leads to the destruction of these monuments to nature, but it is to a certain extent unsanitaty and unsafe to the surrounding environment; i.e. it has no regard for the activity of mud volcanoes and the manner in which they erupt, leading to mud-volcano debris being scattered around and dispersed tosether with all therjo!en!lai contaminants. ALL ABOUT MUD VOLCANOES 51

I In this regard it would be useful to create a mud-volcano reseve in Azerbaijan: a homeland for mud voicanoes. I This would not only be a geological reserve, but would need to exclude engineering and building work, the extraction of natural resources, the burial of waste and litter, and would work in a range of ways to preserve the geological and living I environment in the most intersting areas of mud-volcano development and the largest, most picturesque and distinctive I mud volcanoes. As concerns the smaller mud volcanoes, it might at least be possible to set up notices appealing to people to have a careful regard towards these monuments to nature. The unusal, distinctive splendour of mud volcanoes has long attracted the attention of people, and therefore the necessity to create tourist routes has been ! growing evident for a long time. The creation of mud-volcano reserves would help in the development of organised i tourism. The necessity to set up scientific stations on certain mud volcanoes has been clear for a long time, and would lead to the regular observation of their activity. This would enabie the possibilities for predicting the dangers presented i by voicanoes to be studied, and the mechanism by which they arise. Many fundamental questions in general and petroleum geology etc. could be adressed. Such stations could also serve as bases for providing practical work for geology students. in our view the idea of creating a museum of mud volcanism is also highly attractive. All of the available material ' on this unique natural phenomenon would be gathered here, with a presentation of all currently available mineralogical, lithological etc. findings, and a clear model of the origin and activity of mud volcanoes. The existing scientific-research divi-sions of the Azerbaijan Academy of Sciences, together with the proposed reserve, museum and scientific stations, would act as mutual supports to one another, and would become an integrated system for undertaking scientific research, science teaching, nature conservation work, the organisation of I tourism, and the publication for tourists of guidebooks and popular brochures on mud volcanism.

REFERENCES

1. Aprodov V.A. Volcanoes. Mysl, Moscow, 1982 (in Russian) 2. Aiby A. Eathquakes. Nedra, Moscow, 1982 (translated from Enqlish) 3. Alizadeh Ak.A., F.Efendiyeva, Ad.Aliyev. Dokladi Academiyi Nauk Azerbaijana, 1983, v39, 49-51 (in Russian) 4. Ahrnedov A.G. Mud volcanoes and environment. Baku, 1985 (in Russian) I 5. Barbot de Marni N. and S.Simanov1ch. The geology studing of Binagadi oil region. Tiflis, 1891 (in Russian). 6. Dadashev F.G., I.S.Gullyev, A.A.Feizullayev Rhythmicity of the Earth degassing. AzNINTI, 1987 (in Russian) '. 7 Dadashev F.G. Hydrocarbon gases of mud volcanoes ofAzerbaijan. Azerneshr, Baku, 1963 (in Russian) 8. Gubkin LM.. S.F.Fyodorov, Mud volcanoes of Soviet Union, Moscow, 1938 (in Russian) 9. Guliyev LS., A.A.Felzullayev, S.A.Mamedova. Mud volcanoes an important source of information about the 1 source rock of the deep formations. Abstracts of the third International Conference of the Azerbaijan Society of Petroleum Geologists 'Mud volcanoes of Azerba(jan". Baku, 1996, p.26-29(in Russian) I 10. Gorin V., Z.Buniat-zade. Deep folts, oil-gas volcanism and oil and gas filds of the west flank of South Caspian basin. Azerneshr, Baku, 1971(in Russian). 11. Gymbel C.W. Ueber das Eruptions material des Schlammvulkans von Paterno am Aetna und der Schlammvulkane ' im Allgemeinen. Sitz. - Ber.d. kk. Akad. Wissensch. 1879 (in German) i 12. lvanov V.V., LS.Gullyev. Bull MOIP, 1986, v.61, 1, p.72-80 I 13. Kovalevsky S.A. Mud volcanoes of South Pre-Caspian reqion. Aztoptekhizdat, Baku, 1940. (in Russian) 14. Khain W.E. Regional tectonic., Nedra, Moscow, 1971-1984 (in Russian) 15. Kugler G. The sedimentary volcanism on the Trinidad. ONTI, Baku, 1934, N 211(in Russian) 16. Mud volcanoes of Azerbaijan. Atlas. Academic Press, Baku, 1971 (in Russian) 17. Mud volcanoes of Kerch-Taman provoince. Atlas. Academic Press, Kiev, 1986 (in Russian) 18. Matanov F.A. - "Priroda" 1981, No 6, p.92-93 (in Russian) 19. Mehtlyev Sh.F. and E.N.Khalilov. How the Earth develops. Znanie. Baku, 1984 (in Russian) 20. Nesterovskiy V.A. Mud volcanism - the unique natural phenomenon. Academic Press, Kiev, 1990 (in Russian) 21. Rust H. Volcanoes and volcanism. Mir, Moscow, 1982 (in Russian) 22. Rahrnanov R.R. Mud volcanoes. Nedra, Moscow, 1987 (in Russian) 23. Shnyukov E.F., et a/. Mud voicanism and formation. Naukova Dumka, Kiev, 1971 (in Russian) 24. Shatskii N.S eta/. The dislocation breccia and mud volcanoes in Azerbaijan - Bull. MOIP, N 1-2, 1929 (in Russian) 25. Shteber E.A. Mud volcanoes and origin of oil. Ekatirinoslav, 7914 (in Russian) 26. Valyaev V.M. et al. Doklady Akadernii Nauk SSSR, 1980, v.255, No 5, p. 1204-1207 (in Russian) 27. Vassoevich N.B. Oil and gas potential of Sedimentary basins. Moscow, Nauka, 1988 (in Russian) I CONTENTS

INTRODUCTION

Chapter 1. Mud volcanoes and Zoroastrism.

Chapter 2. But what are mud volcanoes?

Chapter 3. The capriciousness of mud volcanoes.

Chapter 4. The life of mud volcanoes - research and the evidence of eye witnesses.

Chapter 5. Growing mountains.

Chapter 6. How does a mud volcano form? Hypotheses and models.

Chapter 7. The breath of mud volcanoes.

Chapter 8. Mud volcanoes in the embrace of the cosmos.

Chapter 9. The mud volcano as an indicator of deep hydrocarbons.

Chapter 10. The mouth of mud volcanoes: laboratories for gas-hydrate synthesis.

Chapter 11. Mud volcanoes: sources of valuable raw materials.

Chapter 12. The mud volcano: a unique monument to nature.