The subject matter of geology (2800)
Text 2
Text 4
Sedimentary rocks (4500)
1. Learn the words and word combinations before reading:
common - ['kOmqn] - распространенный, общий, часто встречающийся
dolomite - ['dOlqmait] - доломит
conglomerate - [kqn'glOmqrqt] - конгломерат (сцементированная обломочная горная порода)
chemogenic - [kemq'dZenIk] - химогенный
clastic rock - ['klxstik] - обломочная горная порода
overburden - ["quvq'bWdn] - покрывающий сверху
pressure - ['preSq] - давление
squeeze - [skwJz] - сжимать, сдавливать, образовывать трещины
layer - ['leiq] - слой, пласт, прослойка
connate fluids - ['kOneit 'flHid] - реликтовые воды
expel - [iks'pel] - выбрасывать, выталкивать
diagenesis - ['daIqdZenisis]–диагенез, перестройка минералов (совокупность физических и химических превращений рыхлых осадков на дне водных бассейнов под воздействием температур и давлений верхней зоны земной коры)
chemical - ['kemikql] - химический
stratum / pl. strata - ['stra:tqm] - пласт, напластование, формация
superposition - ['sju:pqpq'ziSqn] - напластование
gradation - [grq'deiSqn] - постепенный переход от одной стадии к другой, из одного состояния в другое, сортировка
gap - [gxp] - брешь, промежуток, щель
unconformity - ['Ankqn'fLmiti] - несогласное напластование
lithification - ['litifi"keiSqn] - окаменение, литификация
equal - ['Jkwql] - одинаковый
size - размер
boulder - ['bquldq] - валун, глыба, большой камень
cobble - ['kObl] - булыжный камень, булыжник; крупная галька
successive - [sqksesIv] - следующий один за другим, последовательный
2. Read and translate the text:
Sedimentary rocks formed from sediments cover 75-80% of the Earth’s land area, and include common types such as chalk, limestone, dolomite, sandstone, conglomerate and shale. According to the agents involved in the deposition of sedimentary rocks we may have: 1) mechanically formed sediments (clastic rocks), 2) chemically formed sediments (chemogenic rocks), 3) organically formed sediments (organic rocks), 4) rocks of mixed origin.
Sedimentary rocks are formed because of the overburden pressure* as particles of sediment are deposited out of air, ice, wind, gravity, or water flows carrying the particles in suspension. As sediment deposition builds up, the overburden (or ‘lithostatic’) pressure squeezes the sediment into layered solids in a process known as lithification (‘rock formation’) and the original connate fluids are expelled. The term diagenesis is used to describe all the chemical, physical, and biological changes, including cementation, undergone by a sediment after its initial deposition and during and after its lithification, exclusive of surface weathering.
Sedimentary rocks are laid down in layers called beds or strata. That new rock layers are above older rock layers is stated in the principle of superposition.There are usually some gaps in the sequence called unconformities. These represent periods in which no new sediments were being laid down, or when earlier sedimentary layers were raised above sea level and eroded away. The layers may vary as to kind of material, colour, texture and thickness.
The products of rock decay vary greatly in size, but when subjected to the action of running water they are sorted and graded into particles of approximately equal size in accordance with the strength of current. Grouped then according to the size beginning with the coarsest, the following names for this material may be employed: 1) boulders and cobbles (the coarsest), 2) gravel, 3) sand, 4) clay. Gradation of these into each other is very common. They are unconsolidated mechanical sediments.
Sedimentary rocks contain important information about the history of Earth. They contain fossils, the preserved remains of ancient plants and animals. Coal is considered a type of sedimentary rock. Differences between successive layers indicate changes to the environment which have occurred over time. Sedimentary rocks can contain fossils because, unlike most igneous and metamorphic rocks, they form at temperatures and pressures that do not destroy fossil remains.
The sedimentary rocks cover only 5% of the total of the Earth’s crust.
All rocks disintegrate when exposed to mechanical and chemical weathering at the Earth’s surface. Mechanical weathering is the breakdown of rock into particles without producing changes in the chemical composition of the minerals in the rock. (ice, water, heating and cooling). Chemical weathering is the breakdown of rock by chemical reaction. In this process the minerals within the rock are changed into particles that can be easily carried away.
Sedimentary rocks are economically important in that they can easily be used as construction material because they are soft and easy to cut. In addition, sedimentary rocks often form porous and permeable reservoirs in sedimentary basins in which petroleum and other hydrocarbons can be found.
Notes:
* overburden pressure – давление покрывающих пластов
* as to – относительно
3. Find in the text the equivalents:
вовлеченный в осаждение, механически сформированные осадки, называемые слоями, процесс известный как породообразование, смешанного происхождения, сохраненные останки, химическое выветривание, охлаждение, экономически важные, давление покрывающих пластов.
4. Make the resume of the text.
5. Answer the question: why are sedimentary rocks so important for petroleum geophysicists?
Text 5
Composition of rocks (5400)
1. Learn the words and word combinations before reading:
occur - [q'kW] - залегать, встречаться, происходить
occurrence - [q'kArqns]– месторождение минерала, место залегания руды
crystalline structure -['kristqlain] - кристаллическая структура
common - ['kPmqn]– широко распространенный
halide - [ʹhælaıd] - галоидное соединение, галид
sulfide -['sAlfaId] - сульфид, сернистое соединение
sulfate - ['sAlfeIt] - сульфит, соль серной кислоты
luster - ['lAstq]– глянец, блеск
constituent - [kqn'stItjuqnt] – составная часть, элемент
transparent - [trxn'spxrqnt] - прозрачный
brittle - ['brItl]– хрупкий, ломкий. неустойчивый
effervesce - ["efq'ves] - выделяться в виде пузырьков, шипеть
substitute for – заменять на что-либо, подменять
2. Read and translate the text:
Most rocks are composed of minerals. Minerals are defined by geologists as naturally occurring inorganic solids that have a crystalline structure and a distinct chemical composition. Of course, the minerals found in the Earth's rocks are produced by a variety of different arrangements of chemical elements. A list of the eight most common elements making up the minerals found in the Earth's rocks is described in Table 1.
| Element | Chemical Symbol | Percent Weight in Earth's Crust |
| Oxygen | O | 46.60 |
| Silicon [ʹsılıkən] | Si | 27.72 |
| Aluminum [əʹlu:mınəm] | Al | 8.13 |
| Iron [ʹaıən] | Fe | 5.00 |
| Calcium | Ca | 3.63 |
| Sodium | Na | 2.83 |
Over 2000 minerals have been identified by earth scientists. Table 2 describes some of the important minerals, their chemical composition, and classifies them in one of nine groups.
The Element Group includes over one hundred known minerals. Many of the minerals in this class are composed of only one element. Geologists sometimes subdivide this group into metal and nonmetal categories. Gold, silver, and copper are examples of metals. The elements sulfur and carbon produce the minerals sulfur, diamonds, and graphite which are nonmetallic.
| Table 2: Classification of some of the important minerals found in rocks. | ||
| Group | Typical Minerals | Chemistry |
| Elements | Gold | Au |
| Silver | Ag | |
| Copper | Cu | |
| Carbon (Diamond and Graphite) | C | |
| Sulfur | S | |
| Sulfides | Cinnabar [ʹsınəbɑ:] | HgS |
| Galena [gəʹli:nə] | PBS | |
| Pyrite [ʹpaı(ə)raıt] | FeS2 | |
| Halides | Fluorite [ʹflʋ(ə)raıt] | CaF2 |
| Halite [ʹhælaıt] | NaCl | |
| Oxides | Corundum [kəʹrʌndəm] | Al2O3 |
| Cuprite [ʹkju:praıt] | Cu2O | |
| Hematite [ʹhi:mətaıt] | Fe2O3 | |
| Carbonates (Nitrates and Borates) | Calcite [ʹkælsaıt] | CaCO3 |
| Dolomite [ʹdɒləmaıt] | CaMg(CO3)2 | |
| Malachite [ʹmæləkaıt] | Cu2(CO3)(OH)2 | |
| Sulfates | Anhydrite [ænʹhaıdraıt] | CaSO4 |
| Gypsum [ʹdʒıps(ə)m] | CaSO4 -2(H2O) | |
| Phosphates (Arsenates, Vanadates, Tungstates, and Molybdates) | Apatite [ʹæpətaıt] | Ca5(F,Cl,OH)(PO4) |
| Silicates | Albite [ʹælbaıt] | NaAlSi3O8 |
| Augite [ʹɔ:dʒaıt] | (Ca, Na)(Mg, Fe, Al)(Al, Si)2O6 | |
| Beryl [ʹberıl] | Be3Al2(SiO3)6 | |
| Biotite [ʹbaıətaıt] | K (FE, Mg)3AlSi3O10(F, OH)2 | |
| Hornblende [ʹhɔ:nblend] | Ca2(Mg, Fe, Al)5(Al, Si)8O22(OH)2 | |
| Microcline | KAlSi3O8 | |
| Muscovite [ʹmʌskəvaıt] | KAl2(AlSi3O10)(F, OH)2 | |
| Olivine [ʹɒlıvi:n] | (Mg, Fe)2SiO4 | |
| Orthoclase [ʹɔ:θəkleıs] | KAlSi3O8 | |
| Quartz [kwɔ:ts] | SiO2 | |
| Organics | Amber [ʹæmbə] | C10H16O |
The sulfides form an economically important class of minerals. Many of these minerals consist of metallic elements in chemical combination with the element sulfur. Most ores of important metals such as mercury (cinnabar - HgS), iron (pyrite - FeS2), and lead (galena - PbS) are extracted from sulfides. Many of the sulfide minerals are recognized by their metallic luster. But on account of their usual sparing occurrence in rocks only one of them, pyrite, has a special importance as a rock – making mineral.
The halides are a group of minerals whose principle chemical constituents are fluorine, chlorine, iodine, and bromine. Many of them are very soluble in water. Halides also tend to have a highly ordered molecular structure and a high degree of symmetry. The most well-known mineral of this group is halite (NaCl) or rock salt.
The oxides are a group of minerals that are compounds of one or more metallic elements combined with oxygen, water, or hydroxyl (OH). The minerals in this mineral group show the greatest variations of physical properties. Some are hard, others soft. Some have a metallic luster, some are clear and transparent. Some representative oxide minerals include corundum, cuprite, and hematite.
The carbonates consist of minerals which contain one or more metallic elements chemically associated with the compound CO3. Most carbonates are lightly colored and transparent when relatively pure. All carbonates are soft and brittle. Carbonates also effervesce when exposed to warm hydrochloric acid. Most geologists considered the Nitrates and Borates being subcategories of the carbonates. Some common carbonate minerals include calcite, dolomite, and malachite.
The sulfates are a mineral group that contains one or more metallic element in combination with the sulfate compound SO4. All sulfates are transparent or translucent and soft. Most are heavy and some are soluble in water. Rarer sulfates exist containing substitutes for the sulfate compound. For example, in the chromates SO4 is replaced by the compound CrO4. Two common sulfates are anhydrite and gypsum.
The phosphates are a group of minerals of one or more metallic elements chemically associated with the phosphate compound PO4. The phosphates are often classified together with the arsenate, vanadate, tungstate, and molybdate minerals. One common phosphate mineral is apatite. Most phosphates are heavy but soft. They are usually brittle and occur in small crystals or compact aggregates.
The silicates are by far the largest group of minerals. Chemically, these minerals contain varying amounts of silicon and oxygen. It is easy to distinguish silicate minerals from other groups, but difficult to identify individual minerals within this group. None are completely opaque. Most are light in weight. The construction component of all silicates is the tetrahedron. A tetrahedon is a chemical structure where a silicon atom is joined by four oxygen atoms (SiO4). Some representative minerals include albite, augite, beryl, biotite, hornblende, microcline, muscovite, olivine, othoclase, and quartz.
The organic minerals are a rare group of minerals chemically containing hydrocarbons. Most geologists do not classify these substances as true minerals. Note that our original definition of a mineral excludes organic substances. However, some organic substances that are found naturally on the Earth that exist as crystals resemble and act like true minerals. These substances are called organic minerals. Amber is a good example of an organic mineral.
Notes:
* on account of - из-за, вследствие, на основании
3. Read the following sentences and say if they are taken from the text or not, if they are not correct, correct them.
1. According to geologists minerals are naturally occurring organic solids that have a crystalline structure and a distinct chemical composition. 2. The Elements Group includes over two hundred known minerals. 3. Only one of sulfide minerals has a special importance as a rock-making mineral, it’s mercury. 4. All carbonates are not soft and brittle. 5. Phosphates are usually brittle and occur in small crystals or compact aggregates.
4. Say:
- the most common elements making up the minerals found in the Earth's rocks.
- what organic minerals are.
- which group of minerals is the largest one.
PART 2
Text 1
Migration
Much oil and gas moves away or migrates from the source rock. Migration is triggered both by natural compaction of the source rock and by the processes of oil and gas formation. Most sediments accumulate as a mixture of mineral particles and water. As they become buried, some water is squeezed out and once oil and gas are formed, these are also expelled. If the water cannot escape fast enough, as is often the case* from muddy source rocks, pressure builds up. Also, as the oil and gas separate from the kerogen during generation, they take up more space and create higher pressure in the source rock. The oil and gas move through minute pores and cracks which may have formed in the source rock towards more permeable rocks above or below in which the pressure is lower.
Oil, gas and water migrate through permeable rocks in which the cracks and pore spaces between the rock particles are interconnected and are large enough to permit fluid movement. Fluids cannot flow through rocks where these spaces are very small or are blocked by mineral growth; such rocks are impermeable. Oil and gas also migrate along some large fractures and faults which may extend for great distances if as a result of movement, these are permeable.
Oil and gas are less dense than the water which fills the pore spaces in rocks so they tend to migrate upwards once out of the source rock. Under the high pressures at depth gas may be dissolved in oil and vice versa so they may migrate as single fluids. These fluids may become dispersed as isolated blobs through large volumes of rock, but larger amounts can become trapped in porous rocks. Having migrated to shallower depths than the source rocks and so to lesser pressures the single fluids may separate into oil and gas with the less dense gas rising above the oil. If this separation does not occur below the surface it takes place when the fluid is brought to the surface. Water is always present below and within the oil and gas layers, but has been omitted from most of the diagrams for clarity.
Migration is a slow process, with oil and gas travelling between a few kilometres and tens of kilometres over millions of years. But in the course of many millions of years huge amounts have risen naturally to sea floors and land surfaces around the world. Visible liquid oil seepages are comparatively rare, most oil becomes viscous and tarry near the surface as a result of oxidation and bacterial action, but traces of natural oil seepage can often be detected if sought.
Notes:
* of all the diverse life – из всего многообразия жизненных форм
* as it often the case – как это часто бывает
3. Say what verb forms are underlined and name their functions.
4. Answer the following questions:
1. What is a source rock? 2. Under what conditions is the gas formed from algae and bacteria? 3. What is kerogen? 4. When is viscous heavy oil formed? 5. Where do oil and gas migrate? 6. Is oil less dense than the water which fills the pore space?
Text 2
Trapping Oil and Gas (2750)
1. Learn the words and word combinations before reading:
spill point – точка разлива
fracture -['frxktSq] - раскол, трещина, разрыв
bubble out ['bAbql 'aut] – подниматься пузырьками, бить ключом
break – разрыв, сдвиг, малый сброс
impervious - [im'pWvjqs] - непроходимый, непроницаемый, не пропускающий (влагу и т. п.)
reservoir bed - ['rqzqvwa:] - пласт-коллектор
fault traps - ловушка, образованная сбросом
domed arch - [a:tS] - куполообразная арка
fold - [fquld] - складка, флексура
folded – складчатый
petroleum-bearing formation – нефтеносная свита
combination trap – комбинированная ловушка
truncated - ['trANkeitid] - усеченный, укорачивать, сокращать
pinch - [pIntS] - геол. выклиниваться (о жиле ; тж. ~ out)
piercement dome [piqsi'ment 'dqum]- купол протыкания, протыкающий купол
spindle top – вершина с углублением
2. Read and translate the text:
Oilfields and gasfields are areas where hydrocarbons have become trapped in permeable reservoir rocks, such as porous sandstone or fractured limestone. Migration towards the surface is stopped or slowed down by impermeable rocks such as clays, cemented sandstones or salt which act as seals. Oil and gas accumulate only where seals occur above and around reservoir rocks so as to stop the upward migration of oil and gas and form traps, in which the seal is known as the cap rock. The migrating hydrocarbons fill the highest part of the reservoir, any excess oil and gas escaping at the spill point where the seal does not stop upward migration. Gas may bubble out of the oil and form a gas cap above it; at greater depths and pressures gas remains dissolved in the oil. Since few seals are perfect, oil and gas escape slowly from most traps.
A hydrocarbon reservoir has a distinctive shape, or configuration, that prevents the escape of hydrocarbons that migrate into it. Geologists classify reservoir shapes, or traps, into two types: structural traps and stratigraphic traps.
Structural Traps
Structural traps form because of a deformation in the rock layer that contains the hydrocarbons. Two examples of structural traps are fault traps and anticlinal traps.
Fault Traps
The fault is a break in the layers of rock. A fault trap occurs when the formations on either side of the fault move. The formations then come to rest* in such a way that, when petroleum migrates into one of the formations, it becomes trapped there. Often, an impermeable formation on one side of the fault moves opposite a porous and permeable formation on the other side. The petroleum migrates into the porous and permeable formation. Once there, it cannot get out because the impervious layer at the fault line traps it.
Anticlinal Traps
An anticline is an upward fold in the layers of rock, much like a domed arch in a building. The oil and gas migrate into the folded porous and permeable layer and rise to the top. They cannot escape because of an overlying bed of impermeable rock.
Stratigraphic Traps
Stratigraphic traps form when other beds seal a reservoir bed or when the permeability changes within the reservoir bed itself. In one stratigraphic trap, a horizontal, impermeable rock layer cuts off, or truncates, an inclined layer of petroleum-bearing rock. Sometimes a petroleum-bearing formation pinches out—that is, an impervious layer cuts it off. Other stratigraphic traps are lens-shaped. Impervious layers surround the hydrocarbon-bearing rock. Still another occurs when the porosity and permeability change within the reservoir itself. The upper reaches of the reservoir are nonporous and impermeable; the lower part is porous and permeable and contains hydrocarbons.
Other Traps
Many other traps occur. In a combination trap, for example, more than one kind of trap forms a reservoir. A faulted anticline is an example. Several faults cut across the anticline. In some places, the faults trap oil and gas. Another trap is a piercement dome. In this case, a molten substance—salt is a common one—pierces surrounding rock beds. While molten, the moving salt deforms the horizontal beds. Later, the salt cools and solidifies and some of the deformed beds trap oil and gas. Spindle top is formed by a piercement dome.
Notes:
* come to rest – наткнуться, уткнуться
* seal – относительно непроницаемая горная порода, которая формирует барьер или подобие шапки над или вокруг нефтяного пласта, так, что флюиды не в состоянии двигаться за пределы пласта.
3. Match the word combinations in the first column with their Russian equivalents in the second one.
| Porous sandstone | Слои горной породы |
| Cap rock | нарушенная сбросами антиклиналь |
| Reservoir shape | Пористый песчаник |
| Layers of rock | Точка разлива |
| Fault trap | Разломная моноклиналь |
| Faulted anticline | Очертания месторождения |
| Spill point | Покрывающая порода |
4. Answer the following questions:
1. Where do hydrocarbons become trapped? 2. What stops the upward migration of oil and gas? 3. What are traps? 4. When does a fault trap occur? 5. What is an anticline trap? 6. When do stratigraphic traps form?
Text 3
How much oil and gas (3650)
1. Learn the words and word combinations before reading:
at a profit – с прибылью
porosity - [pL'rO siti] - пористость, ноздреватость; скважинность
permeability - ["pWmjq'biliti] - проницаемость, проходимость
well log – промысловая геофизика, каротаж
rock matrix - ['meitriks] -материнская порода; цементирующая среда
core - колонка породы, керн
fluid saturation ["sxCq'reISqn] - насыщенность флюидом
fraction – фракция, частица
pressure ['preSq] - давление; сжатие, стискивание
drive [draiv]- передача; вытеснение (нефти из коллектора газом, водой) пластовый режим, проходить (горизонтальную выработку), штрек по простиранию пород
sealing [sJliN] fault – непроводящий сброс ант. nonsealing – проводящий
drillsteam test- апробирование пласта испытателем на скважине
drilling rate log = drilling time log – диаграмма скорости проходки скважины; механический каротаж
mud log – газовый каротаж, геохимическое и геофизическое исследование скважин по буровому раствору
tracer – изотопный индикатор
2. Read and translate the text:
When deciding whether to develop a field, a company must estimate how much oil and gas will be recovered and how easily they will be produced. Although the volume of oil and gas in place can be estimated from the volume of the reservoir, its porosity, and the amount of oil or gas in the pore spaces, only a proportion of this amount will be recovered. This proportion is the recovery factor, and is determined by various factors such as reservoir dimensions, pressure, the nature of the hydrocarbon, and the development plan.
More specifically, petroleum engineers have to know:
-- the pore spaces of a rock (porosity). Porosity is the volume fraction of space not occupied by the rock matrix. Not only average porosity is important but also porosity distribution, both vertically and horizontally. Reservoir porosity is determined from measurements on cores and well logs using relationships that are somewhat empirical.
-- how the pore spaces are interconnected (permeability), if permeability is good and the reservoir fluids flow easily, oil, gas and water will be driven by natural depletion into the well and up to the surface.
-- the nature of the fluids filling the pore spaces (fluid saturation). Expansion of the gas cap and water drives oil towards the well bore. Gas and water occupy the space vacated by the oil. In reservoirs with insufficient natural drive energy, water or gas is injected to maintain the reservoir pressure.
-- the energy or pressure that may cause the fluids to flow (drives). Pressure is the driving force in oil and gas production. Reservoir drive is powered by the difference in pressures within the reservoir and the well, which can be thought of as a column of low surface pressure let into the highly pressured reservoir.
-- the vertical and areal distribution of reservoirs and pore-connected spaces, and
-- barriers to fluid flow (sealing and nonsealing faults, stratigraphic barriers, etc.).
These facts have to be determined from available information, which probably consists of: surface seismic, gravity, magnetic, and other geophysical data, borehole logs of various types, cores taken in boreholes, analyses of fluids recovered in drillstem tests, production and pressure data, specialized geophysical measurements, occasionally tracer data, and drilling rate logs, mud logs, and other well data.
Well logs, geologic background, and well-to-well log correlations supplemented by seismic character studies (will be seen further) give an overall picture of the stratigraphy and stratigraphic changes across the reservoir, and production and pressure data (and occasionally tracer data) give information about the connectivity of reservoir members between wells. Surface geophysical data, while lacking the vertical resolution of borehole logs and cores, provides the only data source that gives detailed information about areal distributions.
The proportion of oil that can be recovered from a reservoir is dependent on the ease with which oil in the pore spaces can be replaced by other fluids like water or gas. Tests on reservoir rock in the laboratory indicate the fraction of the original oil in place that can be recovered. Viscous oil is difficult to displace by less viscous fluids such as water or gas as the displacing fluids tend to channel their way towards the wells, leaving a lot of oil in the reservoir.
Each oil and gas reservoir is a unique system of rocks and fluids that must be understood before production is planned. Of course all these facts are to be determined and calculated by a very synergistically working team of development geologists, geophysicists and petroleum engineers using all the available data to develop a mathematical model of the reservoir. Computer simulations of different production techniques are tried on this reservoir engineering model to predict reservoir behaviour during production, and select the most effective method of recovery. For example, if too few production wells are drilled water may channel towards the wells, leaving large areas of the reservoir upswept.
Factors, such as construction requirements, cost inflation and future oil prices must also be considered when deciding whether to develop an oil or gas field. When a company is satisfied with the plans for development and production, they must be approved by the Government, which monitors all aspects of oil field development.
3. Explain the words:
porosity, permeability, fluid saturation, sealing and nonsealing faults, drillstem tests, stratigraphic changes across the reservoir, areal distribution.
4. Answer the questions:
1. How can the volume of oil and gas in place be estimated? 2. What is the reservoir porosity determined from? 4. What gives detailed information about areal distributions? 5. What do a geologist and a geophysicist have to know about oil reservoirs?
Text 4
ADDITIONAL READING
Tasks of a Professional Geologist (11200)
Statement by the National Association of State Boards of Geology (ASBOG®), a non-profit organization comprised of state boards that have developed and administer national competency examinations for the licensure/registration of geologists. (in all the states in the U.S. and the territory of Puerto Rico) The following areas of professional practice contain generalized and some specific activities which may be performed by qualified, professional geologists.
Professional geologists may be uniquely qualified to perform these activities based on their formal education, training and experience. Under each major heading is a group of activities associated with that specific area of geoscience practice. The major areas of professional, geologic practice include, but are not limited to: Research; Field Methods and Communications; Mineralogy; Petrology; Geochemistry; Stratigraphy; Historical, Structural, Environmental, Engineering, and Economic Geology; Geophysics; Geomorphology; Paleontology; Hydrogeology; Geochemistry; and Mining Geology and Energy Resources. These areas are specifically included in the ASBOG® examinations to assure geologic competency. Again, this list represents only a cross-section of possible activities, and does not include all potential professional practice activities.
Also included in this publication is a listing of "Other related activities which may be performed by qualified Professional Geologists." These activities, although not specifically geoscience in content, may be performed by a qualified, professional geologist.
Research, Field Methods and Communications
! Plan and conduct field operations including human and ecological health, safety, and regulatory considerations
! Evaluate property/mineral rights
! Interpret regulatory constraints
! Select and interpret appropriate base maps for field investigations
! Determine scales and distances from remote imagery and/or maps
! Identify, locate and utilize available data sources
! Plan and conduct field operations and procedures to ensure public protection
! Construct borehole and trench logs
! Design and conduct laboratory programs and interpret results
! Evaluate historic land use or environmental conditions from remote imagery
! Develop and utilize Quality Assurance/Quality Control procedures
! Construct and interpret maps and other graphical presentations
! Write and edit geologic reports
! Interpret and analyze aerial photos, satellite and other imagery
! Perform geological interpretations from aerial photos, satellite and other imagery
! Design geologic monitoring programs
! Interpret data from geologic monitoring programs
! Read and interpret topographic and bathymetric maps
! Perform geologic research in field and laboratory
! Prepare soil, sediment and geotechnical logs
! Prepare lithological logs
! Interpret dating, isotopic, and/or tracer studies
! Plan and evaluate remediation and restoration programs
! Identify geological structures, lineaments, or fracture systems from surface or remote imagery
! Select, construct, and interpret maps, cross-sections, and other data for field investigations
! Design, apply, and interpret analytical or numerical models
Mineralogy/Petrology
! Identify minerals and their physiochemical properties
! Identify mineral assemblages
! Determine probable genesis and sequence of mineral assemblages
! Predict subsurface mineral characteristics on the basis of exposures and drill holes
! Identify and classify major rock types
! Determine physical properties of rocks
! Determine geotechnical properties of rocks
! Determine types, effects, and/or degrees of rock and mineral alteration
! Determine suites of rock types
! Characterize mineral assemblages and probable genesis
! Plan and conduct mineralogic or petrologic investigations
! Identify minerals and rocks and their characteristics
! Identify and interpret rock and mineral sequences, associations, and genesis
Geochemistry
! Evaluate geochemical data and/or construct geochemical models related to rocks and minerals
! Establish analytical objectives and methods
! Make determinations of sorption/desorption reactions based upon aquifer mineralogy
! Assess the behavior of dissolved phase and free phase contaminant flow in groundwater and surface water systems
! Assess salt water intrusion
! Design, implement and interpret fate and transport models
! Identify minerals and rocks based on their chemical properties and constituents
Stratigraphy/Historical Geology
! Plan and conduct sedimentologic, and stratigraphic investigations
! Identify and interpret sedimentary structures, depositional environments, and sediment provenance
! Identify and interpret sediment or rock sequences, positions, and ages
! Establish relative position of rock units
! Determine relative and absolute ages of rocks
! Interpret depositional environments and structures and evaluate post-depositional changes
! Perform facies analyses
! Correlate rock units
! Interpret geologic history
! Determine and establish basis for stratigraphic classification and nomenclature
! Establish stratigraphic correlations and interpret rock sequences, positions, and ages ! Establish provenance of sedimentary deposits
Structural Geology
! Plan and conduct structural and tectonic investigations
! Develop deformational history through structural analyses
! Identify structural features and their interrelationships
! Determine orientation of structural features
! Perform qualitative and quantitative structural analyses
! Map structural features
! Correlate separated structural features
! Develop and interpret tectonic history through structural analyses
! Map, interpret, and monitor fault movement
! Identify geological structures, lineaments, fracture systems or other features from surface or subsurface mapping or remote imagery
Paleontology
! Plan and conduct applicable paleontologic investigations
! Correlate rocks biostratigraphically
! Identify fossils and fossil assemblages and make paleontological interpretations for age and paleoecological interpretations
Geomorphology
! Evaluate geomorphic processes and development of landforms and soils
! Identify and classify landforms
! Plan and conduct geomorphic investigations
! Determine geomorphic processes and development of landforms and soils
! Determine absolute or relative age relationships of landforms and soils
! Identify potential hazardous geomorphologic conditions
! Identify flood plain extent
! Determine high water (i.e. flood) levels
! Evaluate stream or shoreline erosion and transport processes
! Evaluate regional geomorphology
Geophysics
! Select methods of geophysical investigations
! Perform geophysical investigations in the field
! Perform geological interpretation of geophysical data
! Design, implement, and interpret data from surface or subsurface geophysical programs including data from borehole geophysical programs
! Identify potentially hazardous geological conditions by using geophysical techniques
! Use wire line geophysical instruments to delineate stratigraphic/lithologic units
! Conduct geophysical field surveys and interpretations, e.g. petrophysical wellbore logging devices, seismic data (reflection and refraction), radiological, radar, remote sensing, electro-conductive or resistive surveys, etc. Includes delineation of mineral deposits, interpretation of depositional environments, formation delineations, faulting, salt water contaminations-intrusion, contaminate plume delineations and other
! Identify and delineate earthquake/seismic hazards
! Interpret paleoseismic history
Hydrogeology/Environmental Geochemistry
! Plan and conduct hydrogeological, geochemical, and environmental investigations
! Design and interpret data from hydrologic testing programs including monitoring plans
! Utilize geochemical data to evaluate hydrologic conditions
! Develop and interpret groundwater models
! Apply geophysical methods to analyze hydrologic conditions including geophysical logging analysis and interpretation
! Determine physical and chemical properties of aquifers and vadose zones
! Define and characterize groundwater flow systems
! Develop water well abandonment plans including monitoring and public water supply wells
! Develop/interpret analytical, particle tracking and mass transport models
! Design and conduct aquifer performance tests
! Define and characterize saturated and vadose zone flow and transport
! Evaluate, manage, and protect groundwater supply resources
! Potentiometric surface mapping and interpretation
! Design and install groundwater exploration, development, monitoring, and pumping/injection wells
! Develop groundwater resources management programs
! Plan and evaluate remedial-corrective action programs based on geological factors
! Evaluate, predict, manage, protect, or remediate surface water or groundwater resources from anthropogenic (man's) environmental effects
! Characterize or determine hydraulic properties
! Interpret dating, isotopic, and/or tracer surveys
! Determine chemical fate in surface water and groundwater systems
! Make determinations of sorption/desorption reactions based upon aquifer mineralogy
! Assess the behavior of dissolved phase and free phase contaminant flow in groundwater and surface water systems
! Assess and develop well head protection plans and source water assessment delineations
Engineering Geology
! Provide geological information and interpretations for engineering design
! Identify, map, and evaluate potential seismic and othergeologic-geomorphological conditions and/or hazards
! Provide geological consultation during and after construction
! Develop and interpret engineering geology investigations, characterizations, maps, and cross sections
! Evaluate materials resources
! Plan and evaluate remediation and restoration programs for hazard mitigation and land restoration
! Evaluate geologic conditions for buildings, dams, bridges, highways, tunnels, excavations, and/or other designed structures
! Define and establish site selection and evaluation criteria
! Design and implement field and laboratory programs
! Describe and sample soils for geologic analyses
! Describe and sample soils for material properties/geotechnical testing
! Interpret historical land use, landforms, or environmental conditions from imagery, maps, or other records
! Conduct geological evaluations for surface and underground mine closure and land reclamation
! Laboratory permeability testing of earth and earth materials
Economic Geology, Mining Geology, and Energy Resources
(including metallic and non-metallic ores/minerals, petroleum and energy resources, building stones/materials, sand, gravel, clay, etc.)
! Plan and conduct mineral, rock, hydrocarbon, or energy resource exploration and evaluation programs
! Implement geologic field investigations on prospects
! Perform geologic interpretations for rock, mineral, and petroleum deposit evaluations, resource assessments, and probability of success
! Perform economic analyses/appraisals
! Provide geologic interpretations for mine development and production activities
! Provide geologic interpretations and plans for abandonment, closure, and restoration of mineral and energy development or extraction operations
! Identify mineral deposits from surface and/or subsurface mapping or remote imagery
! Predict subsurface mineral or rock distribution on basis of exposures, drill hole, or other subsurface data
! Evaluate safety hazards associated with mineral, petroleum, and/or energy exploration and development
! Determine potential uses and economic value of minerals, rocks, or other natural resources
Other related activities which may be performed by qualified Professional Geologists
! Implement siting plans for the location of lagoons and landfills
! Environmental contaminant isocontour mapping
! Conduct water well inventories
! Determine geotechnical aquifer parameters
! Land and water (surface and ground water) use utilized in planning, land usage, and other determinations
! Determine sampling parameters and provide field oversight.
Emergency response activities and spill response planning including implementation and coordination with local, state, and federal agencies
! Develop plans and methods with law enforcement, fire, emergency management agencies, toxicologists and industrial hygienists to determine methods of protection for public health and safety
! Provide training related to hazardous materials and environmental issues related to hazardous materials
! Develop plans and methods with biologists for protection of wildlife during spill events
! Prepare post spill assessments and remediation plans
! Develop and implement site safety plans and environmental sampling plans
! Provide educational outreach related to geological, geotechnical, hydrologic, emergency response and other activities
! Respond to natural disaster events (i.e. floods, earthquakes, etc.) for protection of human health and the environment
! Participate in pre-planning for spill events in coastal or other environmentally sensitive environments
! Develop resource(s) and infrastructure vulnerability assessment plans and reports related to potable and non-potable water supplies, waste water treatment facilities, etc.
Some more information about rocks (3800)
Dykes are intersecting veins. In inclination dykes may vary from vertical to horizontal. Sometimes we may observe them extend, outward from larger masses of intruded rocks.
Effusive or volcanic rocks occur in the forms of domes, sheets and flows. Domes are the names of arched accumulations of lava solidified in the form of beds similar to those of sedimentary rocks.
Sheets are formed on the surface from quiet outwelling of highly molten materials through a) localized opening or volcanic vents and hence connected with volcanic eruptions or b) from fissures not connected with volcanic eruptions. Sheets are similar in form to sedimentary strata and extend to large areas.
Flows are formed in the same manner as sheets but they fill negative reliefs such as valleys and flumes. Flows are much smaller in size than sheets.
Igneous rocks are characterized by a holocrystal line (or granular-crystalline), glassy and porphyritic structure.
Igneous rocks are subdivided according to their chemical composition. Based upon the silicon oxide content the rocks are divided into ultra acid, acid average, basic and ultra basic. The amount of silica present exercises an important influence on the crystallization of the magma. The many hundreds of analyses that have been made of igneous rocks show them to contain the following principal oxides, silica, alumina, iron oxides, ferric, ferrous, magnesia, lime, soda, and potash. These principal oxides as composing igneous rocks do not exist as free oxides, excepting a few cases with but a few exceptions only in small amounts.
TEXTURE OF IGNEOUS ROOKS.
By texture of an igneous rock is meant size, shape and manner of aggregation of its component minerals. It is considered to be an important means of determining the physical conditions under which the rock was formed at or near the surface or at some depth below and hence is recognized to be one of the important factors in the classification of igneous rocks.
Some rocks are sufficiently coarse-grained in texture for the principal mineral to be readily distinguished by unaided eye. In others their minerals are too small to be seen even with the aided eye. There are also those in which no minerals appeared to have crystallized. Instead the magma has solidified as a glass.
KINDS OF TEXTURE.
Expressing so closely the conditions under which rock magmas solidify the texture is recognized to be an important property of rocks and one of the principal factors in their classifications.
In megascopic description of igneous rocks five principal textures were reported to exist. They are glassy, dense or felsitic, porphyritic, granitoid and fragmental.
According to the size of mineral grains we may recognize: 1) fine-grained ; 2) medium-grained; 3) coarse-grained rocks.
DESCRIPTION OF SOME IGNEOUS ROOKS.
Granites are known to be composed of feldspar and quartz usually with mica or hornblende, rarely pyroxene.
The chemical composition of granite is now regarded to be of less economic importance than the mineral composition.
PHYSICAL PROPERTIES.
The usual colour of granite is reported to be some shade of grey though pink or red varieties are likely to occur depending chiefly upon that of the feldspar and the proportion of the feldspar to the dark minerals. Specific gravity ranges from 2.65 to 2.75.The percentage of absorption is very small. Crushing strength is very high ranging from 15.000 to 20.000 pounds per square inch (psi).
These properties render the rock especially desirable for building purposes.
DIORITE. MINERAL COMPOSITION.
The diorites are granular rocks which are known tobe composed of plagioclass as the chief feldspar and hornblende or biotite or both.
Augite is likely to be present in some amount and some ortho - class occurs in all diorites. The name diorite is applied to those granular rocks in which hornblende is found to equal or exceed feldspar in amount. Because of the fine-grained texture it is not possible in manycases to determine by megascopic examination the dominant feldspar.
CHEMICAL COMPOSITION.
The most important points to be observed inthe chemical composition of normal diorites are lower silica content but notably increased percentages of the bases, iron, lime and magnesia over the granites.
PHYSICAL PROPERTIES.
Diorites are usually of a dark or greenishcolour, sometimes almost black depending upon the colour of hornblende and its proportion to feldspar. They have a higher specific gravity than granites, ranging from 2.82 to 5.0. They show a high compressive strength and a low percentage of absorption.
Preparing to Drill (4100)
Once the site has been selected, it must be surveyed to determine its boundaries, and environmental impact studies may be done. Lease agreements, titles and right-of way accesses for the land must be obtained and evaluated legally. For off-shore sites, legal jurisdiction must be determined.
Once the legal issues have been settled, the crew goes about preparing the land:
1. The land is cleared and leveled, and access roads may be built.
2. Because water is used in drilling, there must be a source of water nearby. If there is no natural source, they drill a water well.
3. They dig a reserve pit, which is used to dispose of rock cuttings and drilling mud during the drilling process, and line it with plastic to protect the environment. If the site is an ecologically sensitive area, such as a marsh or wilderness, then the cuttings and mud must be disposed offsite -- trucked away instead of placed in a pit.
Once the land has been prepared, several holes must be dug to make way for the rig and the main hole. A rectangular pit, called a cellar, is dug around the location of the actual drilling hole. The cellar provides a work space around the hole, for the workers and drilling accessories. The crew then begins drilling the main hole, often with a small drill truck rather than the main rig. The first part of the hole is larger and shallower than the main portion, and is lined with a large-diameter conductor pipe. Additional holes are dug off to the side to temporarily store equipment -- when these holes are finished, the rig equipment can be brought in and set up.
Setting Up the Rig
Depending upon the remoteness of the drill site and its access, equipment may be transported to the site by truck, helicopter or barge. Some rigs are built on ships or barges for work on inland water where there is no foundation to support a rig (as in marshes or lakes). Once the equipment is at the site, the rig is set up. Here are the major systems of a land oil rig:
- Power system
- large diesel engines - burn diesel-fuel oil to provide the main source of power
- electrical generators - powered by the diesel engines to provide electrical power
- Mechanical system - driven by electric motors
- hoisting system - used for lifting heavy loads; consists of a mechanical winch (drawworks) with a large steel cable spool, a block-and-tackle pulley and a receiving storage reel for the cable
- turntable - part of the drilling apparatus
- Rotating equipment - used for rotary drilling
- swivel - large handle that holds the weight of the drill string; allows the string to rotate and makes a pressure-tight seal on the hole
- kelly - four- or six-sided pipe that transfers rotary motion to the turntable and drill string
- turntable or rotary table - drives the rotating motion using power from electric motors
- drill string - consists of drill pipe (connected sections of about 30 ft / 10 m) and drill collars (larger diameter, heavier pipe that fits around the drill pipe and places weight on the drill bit)
- drill bit(s) - end of the drill that actually cuts up the rock; comes in many shapes and materials (tungsten carbide steel, diamond) that are specialized for various drilling tasks and rock formations
- Casing - large-diameter concrete pipe that lines the drill hole, prevents the hole from collapsing, and allows drilling mud to circulate
- Circulation system - pumps drilling mud (mixture of water, clay, weighting material and chemicals, used to lift rock cuttings from the drill bit to the surface) under pressure through the kelly, rotary table, drill pipes and drill collars
- pump - sucks mud from the mud pits and pumps it to the drilling apparatus
- pipes and hoses - connects pump to drilling apparatus
- mud-return line - returns mud from hole
- shale shaker - shaker/sieve that separates rock cuttings from the mud
- shale slide - conveys cuttings to the reserve pit
- reserve pit - collects rock cuttings separated from the mud
- mud pits - where drilling mud is mixed and recycled
- mud-mixing hopper - where new mud is mixed and then sent to the mud pits
- Derrick - support structure that holds the drilling apparatus; tall enough to allow new sections of drill pipe to be added to the drilling apparatus as drilling progresses
- Blowout preventer - high-pressure valves (located under the land rig or on the sea floor) that seal the high-pressure drill lines and relieve pressure when necessary to prevent a blowout (uncontrolled gush of gas or oil to the surface, often associated with fire)
 Anatomy of an oil rig |
 Drill-mud circulation system |
ЧТЕНИЕ ХИМИЧЕСКИХ ФОРМУЛ
Латинские буквы, входящие в уравнения или обозначающие названия химических элементов, читаются как английские буквы в алфавите.
В формулах химических соединений и уравнений химических
реакций цифра перед обозначением элемента указывает число молекул и читается следующим образом:
2MnO2 [‘tu:’molikju:lz əv ‘em ‘en ‘ou ’tu:]
Знаки «+» и «–», стоящие в левом верхнем углу, обозначают
положительную и отрицательную валентность иона:
Н+ hydrogen ion [‘haidridZən ‘aiən] или
univalent positive hydrogen ion [ju:ni’veilənt ‘pozitiv ‘hai- dridZən ‘aiən]
Cu++
divalent positive cuprum ion [‘daiveilənt ‘pozətiv ‘kju:prəm ‘aiən]
Al
+++
trivalent positive aluminium ion [‘tri: veilənt ‘pozətiv ,ælju’minijəm aiən]
Cl
–
negative chlorine ion [‘negətiv ‘klo:’ri:n ‘aiən] или
negative univalent chlorine ion [‘negətiv ‘ju:ni’veilənt ‘klo:’ri:n ‘aiən]
Знак «–» или «:» обозначает одну связь и не читается:
.. Cl
:Cl : ÷
:Cl:C:Cl или Cl ¾ C ¾ Cl [‘si: ‘si: ‘el ‘fo:]
:Cl: ú
Cl
Знак «=» или «::» обозначает две связи и также не читается:
..
:О::С::О: или О=С=О [‘si: ‘ou ‘tu:]
Знак «+» читается: plus, and или together with
Знак «=» читается: give или form
Знак «→» читается: give, pass over to или lead to (пример 3)
Знак «←» читается: forms или is formed from (пример 8) или
form или are formed (пример 7: так как подлежащее во мн. ч.)
( ) round brackets [‘raund ‘brækits] – круглые скобки
[ ] square brackets [‘skwεə ‘brækits] – квадратные скобки
·(x) multiplication sign (знак умножения) (пример 10)
Примеры чтения химических формул
1. 4KCl [‘fo:’molikju:lz əv ‘ke ‘si: ‘el]
2. 4HCl + O2 = 2Cl2 + 2H2O [‘fo:’molikju:lz əv ‘eit∫ ‘si: ‘el plAs ‘ou
‘tu: ‘giv ‘tu: ‘molikju:lz əv ‘si: ‘el ‘tu: ənd ‘tu: ‘molikju:lz əv ‘eit∫ ‘tu: ‘ou]
3. Zn + CuSO4 = Cu + ZnSO4 [‘zed ‘en ‘plAs ‘si: ‘ju: ‘es ‘ou ‘fo:
‘giv ‘si: ‘ju: ‘plAs ‘zed ‘en ‘es ‘ou fo:]
4. PCl3 + 2Cl → PCl5 [‘pi: ‘si: ‘el ‘θri: plAs ‘tu: ‘molikju:lz əv ‘si:
‘el ‘giv ‘pi: ‘si: ‘el ‘faiv]
5. H2 + J2 ← 2HJ [‘eit∫ ‘tu: ‘plAs ‘dZei ‘tu: ‘fo:m ənd a: ‘fo:md
frəm ‘tu: ‘molikju:lz əv ‘eit∫ ‘dZəi]
6. C2H2 + H2O → CH3CHO [‘si: ‘tu: ‘eit∫ ‘tu: ‘plAs ‘eit∫ ‘tu: ‘ou
giv ‘si: ‘eit∫ ‘θri: ‘si: ‘eit∫ ‘ou]
7. N2 + 3H2 ← 2NH3 [‘en ‘tu: ‘plAs ‘θri: ‘molikju:lz əv ‘eit∫ ‘tu:
‘fo:m ənd a: ‘fo:md frəm ‘tu: ‘molikju:lz əv ‘en ‘eit∫ ‘θri: ]
8. AcOH ← AcO-
+ H+
[‘ei ‘si: ‘ou ‘eit∫ ‘fo:mz ənd iz ‘fo:md ‘frəm ‘ei ‘si: ‘negətiv ‘oksidZən ‘aiən ‘plAs ‘haidrodZən ‘aiən ]
H
|
H — H — C — H [‘si: ‘eit∫ ‘fo:]
|
H
9. Al2 (SO4)3 [‘ei ‘el ‘tu: ‘raund ‘brækits ‘oupənd ‘es ‘ou ‘fo ‘raund ‘brækits ‘klousd ‘θri: ]