In areas where the rocks outcrop at the surface, a careful study of the surface and its structural relations may be considered to be a guide to the subsurface conditions and thus aid in predicting the most favorable sits for the location of a test well to be drilled.
The surface survey should be directed by a competent geologist, who may know in advance whether or not petroliferous strata are likely to be found beneath the area under observation. Then the problem resolves itself into the locating and mapping of structure favourable for drilling. The possible thickening or thinning of formations and the probability of overlapping and unconformable relations of strata must be taken into account, as the presence or absence of either will determine whether or not the surface outcrops and the surface strata are closely related.
Even though the surface outcrops are favourable, and petroliferous strata are known to underlie the area, no concentrations of oil in commercial quantities will exist unless the surface structures are favourable, as well. This, of course, can be determined accurately only by drilling a test well, since the surface strata often do not conform to the surface bed. But with a clear knowledge of the nature and relationships of structure, the careful geologist will devote much time and effort to make the proper deductions as to the existence of favourable underground conditions before any drilling is commenced. All possible area for drilling purposes, the presence or absence of bituminous outcrops, gas emanations, and oil seeps should be investigated; and the dip strike of the outcropping rocks must be carefully measured to make a surface contour map of the area. An aerial map will also assist, as it will indicate the positions of the outcrops and point out the relative position of any faults that are in evidence at the surface. In addition to this, a detailed study of the fossil remains in the surface rocks should be made if the geologic age and sequence of the strata are unknown. Also, surface outcrops several miles distant may furnish an appreciable amount of direct evidence as to the subsurface conditions of the sediments beneath area under observation.
Exercises
I. Ответьте на вопросы:
1. How can one determine that the surface structures are favourable for oil?
2. Is it enough to know only the surface indications for discovering oil?
3. What is to be known to make a surface contour map of the area?
4. Do the surface strata always conform to the subsurface beds?
5. Why is it important to study the fossil remains in the surface rocks?
II. Переведите на русский язык:
1. To predict the most favourable site for the location of a test well geologists should study surface indications of oil.
2. Surface indications to serve as a guide to the subsurface conditions should be thoroughly studied by oil geologists to choose the proper place for drilling.
3. Geologists consider oil and gas seeps, asphaltic outcrops and some other surface indications to be of interest for discovering oil in commercial quantities.
4. To have a contour map of the region under investigation is very important for oil geologists.
III. Переведите на английский язык:
1. Считают, что остатки ископаемых представляют интерес, так как они помогут определить геологический возраст пластов.
2. Сделать контурную карту района – трудная задача.
3. Разведывательная скважина, которую нужно будет пробурить, покажет нам, нефтеносны ли подземные пласты.
4. Чтобы найти нефть, нужно учесть все данные относительно изучаемого района.
IV. Назовите синонимы к следующим словам:
to aid, well, to direct, beneath, to resolve, formation, to take into account, bed, accurately, as to, often, to commence, to draw a conclusion, purpose, several, evidence.
V. Назовите антонимы к следующим словам:
careful, unfavourable, direct, impossible, thick, unconformable, absence, to close, to underlie, accurate, often, known.
VI. Переведите на русский язык:
1) subsurface strata
2) commercial oil pools
3) petroliferous substances
4) petroleum producing regions
5) the location of a test well
6) the surface survey
7) drilling mud
8) in paying quantities
9) pay sand
LESSON THREE
Выучите следующие слова и выражения к тексту:
accumulation – накопление, собирание
adopt – принимать, усваивать
afford – давать, позволять, предоставлять
alter – изменять, переделывать
bailer – ковш, черпак
bit – бур, сверло
body – тело, корпус, кузов
capacity – объем, величина, вместимость, мощность, нагрузка
channel – канал, ход, путь
clay - глина
compact – компактный, плотный, сжатый, сплошной
compose - составлять
conglomerate – конгломерат, обломочная горная порода, накоплять
consolidate – затвердевать, укрепляться
continuity – непрерывность, целостность
cool – охлаждать, холодный, прохладный
dense - плотный
driller - бурильщик
erode – размывать, смывать, разъедать, разрушать
erosion - эрозия
flow – поток, струя, течение, текучесть
fluid – жидкость, газ, раствор
gradation – градация
hoist – подъемник
igneous – огненный, изверженный, вулканического происхождения
lithologic - литологический
opening – отверстие, окно, щель, расщелина, пора, пустота (в породе)
originate – давать начало, порождать, создавать, происходить, возникать
per – по, через, посредством, согласно
percentage - процент
permeable - проницаемый
pulverize – растирать, размельчать, распылять
rate – норма, ставка, тариф, пропорция, коэффициент
remove – передвигать, перемещать, устранять, удалять
represent – изображать, представлять, воображать
reservoir – бассейн, водохранилище, запас, источник
sand - песок
sedimentary - осадочный
serve - служить
space – расстояние, интервал, пространство, зазор, место
storage – хранение, хранилище, накопление
stream - поток
sufficient - достаточный
suspension – прекращение, приостановка, суспензия
volume - объем
on account of – из-за, вследствие
to a certain extent – в определенной степени
fissure - растрескиваться
RESERVOIR ROCKS
An oil and gas reservoir may be defined as a body of porous and permeable rock containing oil and gas through which fluids may move towards openings under the pressure that exist or that can be applied.
The lithologic properties of the reservoir rock are important in determining storage capacity resistance of flow and the rate at which fluids may enter the wells. The size and shape of the pore spaces, their continuity and the percentage of the total volume of the rock that they represent are factors of great importance. Reservoir rocks are usually sand, sandstones, unconsolidated sands, conglomerates or limestones: that is rocks affording sufficient space to permit storage of fluids to the extent of 10 per cent or more of the volume of the rock and having pore spaces sufficiently large and continuous to allow movement of fluids through them.
The term “oil sand” has often been loosely applied to all kinds and types of rock which serve as underground reservoirs for petroleum. The term is known to have originated in Pennsylvania, where the oil reservoir rocks in the first wells drilled were sandstones. These sandstones, after being finally pulverized by the drill bit and hoisted to the surface in a bailer, appeared to the drillers as sands and since they contained oil, the name “oil sand” was readily and conveniently adopted.
Sedimentary rocks, or rocks which have been eroded and transported by wind and stream action and finally deposited from suspension in water, often contain sufficient pore space after compaction and consolidation to permit accumulation of petroleum in commercial quantities. Oil being accumulated in sedimentary makes them one of the most important objectives for oil geologists. Common rocks of this type are fissured and sandy shales, porous or channeled limestones, and various gradations of sandstones.
Igneous rocks, or those that have been produced by the cooling of molten rock masses /magma/, on account of their being usually dense when in place and unaltered, seldom serve as reservoirs for oil and gas. Typical rocks of this class are granites and basalts /trap rocks/. However, sands and gravels composed largely of ingenious rock material which has been removed from the original ingenious rock mass by weathering and erosion sometimes serve as oil reservoir rocks.
Exercises
I. Ответьте на вопросы:
1. To what kind of rocks is the term “oil sand” usually applied?
2. Where did the term “oil sand” originate?
3. What rocks contain much pore space for oil accumulation?
4. What sedimentary rocks do you know?
5. Can igneous rocks serve as reservoirs for oil and gas?
6. Why cannot igneous rocks serve as reservoirs for oil?
7. What rocks of igneous origin do you know?
II. Переведите на русский язык:
1. They knew of our having discovered numerous gas seeps, asphaltic outcrops and oil springs in the ragion under investigation.
2. Before drilling the well one should collect all the data available about the geologic structure of the region.
3. Igneous rocks, on account of their being usually dense, do not appear to serve as good reservoirs for oil and gas.
4. Without being subjected to weathering and erosion, igneous rocks seldom serve as reservoirs for oil and gas.
5. We know of oil and gas being often found in rocks which have been eroded and deposited from suspension in water, i.e. in sedimentary rocks.
III. Переведите на английский язык:
1. Название «нефтеносный песок» часто применяется ко всем видам осадочных пород.
2. Часто осадочные породы образуются в результате эрозии и выветривания изверженных пород.
3. Песок, песчаные сланцы и пористые известняки, как известно, являются обычными породами этого типа.
4. Изверженные породы вследствие их плотности редко служат хорошими резервуарами для нефти и газа.
IV. Назовите синонимы к следующим словам:
to apply, rate, important, too, to originate, quantity, sufficient, common, to alter, on account of, to hoist, finally, fluid.
V. Образуйте существительные от следующих слов:
to define, to resist, to weather, to transport, to press, to permit, to erode, to deposit, to compact, to consolidate, to compose.
VI. Переведите на английский язык:
1). Происхождение нефти
2). Бурильным долотом
3). Накопление нефти
4). Осадочные породы района
5). Буровые скважины
6). Поднимать долото из скважины
7). При помощи выветривания
8). После сжатия пород
9). Трещиноватые породы
10). Рыхлый песок
LESSON FOUR
Выучите следующие слова и выражения к тексту:
absolute – чистый, беспримесный
angular – угловатый
approach – приближение, подход
arrangement – расположение, классификация, устройство, тех. монтаж
assort – сортировать, классифицировать
assume – принимать на себя, предполагать, допускать
attain – достигать, добиться
average – среднее число, обычный, средняя величина
below – ниже, внизу
cause – причина, повод, дело
coarse – грубый, сырой, необработанный
cubic – кубический
develop – развивать, разрабатывать
diameter – диаметр
distribution – распределять, распространять
enough – достаточно
extremely – чрезвычайно
face – поверхность, срез
fit – пригонять, прилаживать, устанавливать
fine – grained – мелкозернистый
fragment – фрагмент, остаток, кусок, обломок, часть
friction – трение, сцепление
generally – в общем
grain – зерно, частица материала
granular – зернистый, гранулированный
hence – отсюда, с этих пор
impose – налагать, спускать, облагать, навязать
initial – начальный, первоначальный
interstice – пустота, щель, промежуток
irregular – несимметричный, неровный, неравномерный
irrespective – безотносительный, независимый
materially – существенным образом
occur – встречаться, попадаться
ordinarily – обычно
pack – упаковывать, спрессовать, packed - плотный
prehistoric – доисторический
porosity – пористость, скважинность
recovery – регенерация, извлечение, утилизация добычи
reduce – уменьшать
reference – ссылка, упоминание
rest – покоиться, класть
retard – замедлять, задерживать
solution – раствор
subcapillary – субкапиллярный
tabular – плоский, пластинчатый
uniform – однородный, равномерный, постоянный, сплошной
void – пустота, пора
due to – благодаря
bedding plane – плоскость напластовывания
for example – например
paying quantities – промышленные количества
as a result – в результате
per unit volume – на единицу объема
with reference to – ссылаясь на
in such a manner – таким образом