NEW
Font size
Worksheetsmidterm+endterm geo
Total questions: 58
Worksheet time: 29mins
What is the function of a "cap rock" in a petroleum reservoir?
a) To allow the free flow of petroleum to the surface
b) To seal and trap petroleum within the reservoir by acting as an impermeable barrier
c) To enhance the permeability of the reservoir and facilitate extraction
What is "kerogen"?
a) A liquid hydrocarbon that can be extracted directly from oil reservoirs
b) A solid hydrocarbon, insoluble in petroleum solvents, that generates petroleum when subjected to heat
c) A gaseous compound found in natural gas deposits, used for energy production
What is a "source rock" in the context of petroleum generation?
a) A fine-grained, organic-rich sediment capable of generating petroleum
b) A rock that acts as a reservoir for already formed petroleum
c) A type of rock used to trap natural gas for extraction
Which of the following fractions is produced during the crude oil distillation process in a distillation tower?
a) Gasoline, kerosene, diesel oil, fuel oil
b) Hydrogen, ammonia, carbon dioxide
c) Sulfur, methane, nitrogen gas
What is the process called during which kerogen breaks down into liquid hydrocarbons (oil) and gas?
a) Catagenesis
b) Diagenesis
c) Metagenesis
What are the geochemical indicators used to estimate the historical temperatures experienced by sedimentary rocks called?
a) Paleothermometers
b) Temperature Ranges
c) Thermogenesis
At what stage and under what conditions does natural gas formation begin, where kerogen breaks down into gaseous hydrocarbons?
a) Metagenesis, at depths beyond 4 km and temperatures above 120°C
b) Diagenesis, at depths less than 2 km and temperatures below 60°C
c) Catagenesis, at depths between 2 and 4 km and temperatures between 60°C and 120°C
What is a "trap" in the context of petroleum geology?
a) A structural or stratigraphic configuration that prevents hydrocarbons from migrating further
b) A rock formation that enhances the migration of hydrocarbons
c) A surface feature that allows hydrocarbons to seep out of the ground
What is the name of the water trapped in sediment during deposition, often saline due to long interaction with surrounding minerals?
a) Juvenile Water
b) Meteoric Water
c) Connate Water
What is the difference between normal pressure and abnormal pressure in subsurface formations?
a) Normal pressure occurs when fluid pressure is higher than expected, while abnormal pressure is always lower than the overlying water column pressure.
b) Normal pressure occurs when fluid pressure is equal to the weight of the overlying water column, while abnormal pressure occurs when fluid pressure is either higher or lower than expected.
c) Normal pressure is the pressure found in gas reservoirs, while abnormal pressure is only found in oil reservoirs.
Which of the following formulas correctly represents hydrostatic pressure?
P=pgh
P=mgh
P=p/gh
Which of the following are common causes of abnormal pressures in subsurface formations?
a) Water infiltration, gas diffusion, tectonic uplift, soil hardening
b) Erosion, fluid condensation, sediment cooling, hydrocarbon evaporation
c) Compaction disequilibrium, fluid expansion, aquathermal pressuring, hydrocarbon generation
What is "secondary migration" in the context of hydrocarbon movement?
a) The process where hydrocarbons migrate through impermeable rocks, bypassing traps, and fail to accumulate in deposits.
b) The movement of hydrocarbons through permeable rock towards a trap, driven by buoyancy, where they form a deposit when encountering a seal
c) The movement of hydrocarbons from deep within the Earth's core directly into oil reservoirs, bypassing any permeable rock layers
What is the chemical formula of dolomite?
CaMg(CO3)2
CaCO3
MgCO3
What is used to show the stability fields of aragonite, calcite, and dolomite in relation to changes in salinity?
a) Mg/Ca temperature
b) Mg/Ca salinity
c) Mg/Ca pressure
Which of the following factors can affect reservoir continuity by creating barriers?
a) Depositional barriers, diagenetic barriers, structural barriers
b) Chemical barriers, magnetic barriers, gravitational barriers
c) Hydraulic barriers, tectonic barriers, thermal barriers
Which methods are commonly used to manage and assess reservoir continuity?
a) Seismic interpretation, well correlation, pressure testing
b) Fluid sampling, temperature monitoring, gravitational mapping
c) Magnetic surveying, core sampling, flowrate estimation
What is the primary difference between carbonate rocks and fractured rocks?
a) Carbonate rocks are primarily made of carbonate minerals, while fractured rocks are any type of rock that has been affected by natural fractures.
b) Carbonate rocks are defined by their mineral composition, while fractured rocks are defined by the presence of cracks or breaks regardless of their composition.
c) Carbonate rocks have high natural permeability, while fractured rocks are always impermeable.
Which methods can be used to identify tectonic faults?
a) Seismic interpretation, well correlation
b) Core sampling, temperature logging
c) Fluid analysis, magnetic surveying
Which of the following are necessary conditions for the commercial accumulation of oil?
a) Volcanic activity, organic-poor source rock, thin cap rock, unstable trap, high fluid migration
b) High geothermal gradient, freshwater influx, rapid tectonic uplift, shallow water table, low pressure
c) Organic-rich source rock, sufficient heating, reservoir with porosity and permeability, impermeable cap rock, trap formation, favorable timing, preservation of accumulation
What is a "trap" in the context of hydrocarbon accumulation?
a) A geological structure that holds hydrocarbons by preventing their upward migration
b) A surface feature that allows hydrocarbons to seep out of the ground
c) A type of reservoir that enhances the migration of hydrocarbons towards the surface
What is a "seal" in the context of hydrocarbon accumulation?
a) An impermeable rock layer that prevents hydrocarbons from escaping
b) A porous rock layer that allows hydrocarbons to migrate freely
c) A surface feature that traps hydrocarbons through gravity
What is the name of the trap type where porous and permeable sedimentary rock lenses are surrounded by impermeable rock?
a) Lens traps
b) Fault traps
c) Anticline traps
Which of the following are major mechanisms responsible for the formation of basins?
a) Erosion, sediment deposition, sea level rise
b) Crustal compression, crustal tension, vertical movements
c) Volcanic activity, tectonic folding, sediment compaction
Which of the following are types of plate boundaries?
a) Sedimentary boundaries, Erosive boundaries, Volcanic boundaries
b) Convergent boundaries, Divergent boundaries, Transform boundaries
c) Trailing (Rift) boundaries, Subductive boundaries, Transcurrent boundaries
How are cratonic basins classified?
a) Subcratonic basins: Entirely on oceanic crust, Supercratonic basins: Partly on continental crust
b) Pericratonic basins: On tectonic plate boundaries, Hypocratonic basins: Below sea level
c) Intracratonic basins: Entirely on continental crust, Epicratonic basins: Partly on continental and oceanic crust
What is the definition of a petroleum system?
a) A static structure for storing petroleum in geologic formations
b) A dynamic system for generating and concentrating petroleum, functioning in geologic space and time
c) A mechanism for artificially creating hydrocarbons in laboratories
What does Gussow’s Principle explain?
a) The process by which hydrocarbons form within shallow rock layers
b) How hydrocarbons migrate from the deep basin center to the flanks, filling traps in a predictable order
c) The movement of hydrocarbons through impermeable rock layers to reach the surface
Why is it important to study plate tectonics theory in the context of basin formation?
a) It explains how ocean currents influence basin sedimentation
b) It connects the formation of basins to tectonic processes, making classifications more genetic
c) It focuses solely on the formation of volcanic basins
What is the correct order of the stages in oil and gas exploration?
A) Regional geological and geophysical works → Exploration works → Prospecting works
B) Exploration works → Prospecting works → Regional geological and geophysical works
C) Regional geological and geophysical works → Prospecting works → Exploration works
D) Prospecting works → Exploration works → Regional geological and geophysical works
What is the primary activity during seismic acquisition?
A) Recording and creating seismic data
B) Mapping horizons and structures
C) Drilling exploration wells
D) Analyzing seismic sections
What is the purpose of seismic interpretation?
A) To record seismic data
B) To identify seismic surveys
C) To identify horizons and structures and map potential hydrocarbon reserves
D) To drill exploration wells
Which of the following is an objective of geological exploration activities?
A) Maximize production rates
B) Identifying and evaluating potential hydrocarbon reserves in geological structures
C) Transporting hydrocarbons to processing facilities
D) Reducing carbon emissions during production
Why is exploratory drilling considered an essential evaluation method?
A) It identifies the best production techniques
B) It determines the presence and economic viability of hydrocarbons
C) It reduces the cost of geological surveys
D) It maps surface geological formations
Which method uses geological and petrophysical data to calculate the amount of hydrocarbons in place?
A) Decline Curve Analysis
B) Analog Method
C) Volumetric Method
D) Probabilistic Methods
Which method incorporates uncertainties and provides a range of outcomes for recoverable volumes?
A) Volumetric Method
B) Decline Curve Analysis
C) Probabilistic Methods
D) Analog Method
Which of the following methods uses tools like Monte Carlo simulations?
A) Volumetric Method
B) Decline Curve Analysis
C) Analog Method
D) Probabilistic Methods
What is the primary concern of geological risk in oil and gas exploration?
A) Combining geological, technical, and economic risks to calculate the likelihood of a successful discovery
B) Variations in oil prices and production costs
C) Uncertainty in subsurface geology, such as reservoir rocks or effective seals
D) Challenges in extraction and recovery technologies
In Darcy’s equation, which parameter represents the ability of a rock to transmit fluids?
A) Pressure gradient
B) Fluid viscosity
C) Permeability
D) Flow rate
How are contingent resources different from prospective resources?
A) Contingent resources are undiscovered, while prospective resources are discovered.
B) Contingent resources are discovered, while prospective resources are estimated from undiscovered accumulations.
C) Contingent resources are commercially recoverable, while prospective resources are not.
D) Contingent resources are based on indirect evidence only.
Which method analyzes historical production data to predict future production and remaining reserves?
A) Material Balance Method
B) Decline Curve Analysis
C) Stochastic Modeling
D) Volumetric Method
What is the primary purpose of stochastic modeling (e.g., Monte Carlo Simulation) in reserve estimation?
A) Revising reserves during production.
B) Predicting production rates based on decline trends.
C) Accounting for uncertainties by simulating multiple scenarios for each parameter.
D) Measuring reservoir pressure under different conditions
For which geological reserves is the recovery factor estimated?
A) For profitable (recovarable) geological reserves
B) For unprofitable geological reserves
C) For profitable and unprofitable geological reserves
D) For not economically feasible extraction
What is the first step in reserves estimation in a three-dimensional model?
A) Determining the average porosity of reservoir rocks.
B) Determining the area and volume of hydrocarbon-bearing reservoirs.
C) Determining the hydrocarbon-saturated pore volume.
D) Bringing hydrocarbon volumes to standard conditions.
What is the final step in the static model reserves calculation?
A) Determining the total area of reservoir rocks containing hydrocarbons.
B) Calculating the average porosity of the reservoir rocks.
C) Adjusting the volume of hydrocarbons to standard conditions.
D) Estimating the reservoir's economic viability.
What does the average oil and gas saturation of reservoir rocks represent?
A) The proportion of hydrocarbons to the total reservoir volume.
B) The ratio of hydrocarbon-saturated pore volume to the total pore volume of the reservoir rocks.
C) The hydrocarbon volume at standard conditions.
D) The density of hydrocarbons in the reservoir rocks.
What distinguishes Category C1 reserves?
A) They are reserves estimated using geological and geophysical data.
B) They are discovered reserves confirmed through drilling and well testing.
C) They are reserves located in areas with no geological justification for hydrocarbons.
D) They are reserves based on assumptions without testing.
What characterizes Category C2 reserves?
A) Reserves confirmed through drilling and deposit testing.
B) Reserves preliminarily estimated based on geological and geophysical data.
C) Reserves justified by the presence of established deposit characteristics.
D) Reserves that are confirmed through drilling
What characterizes a Zero-offset VSP?
A) The energy source is placed at a distance from the borehole.
B) Multiple sources are arranged radially.
C) The energy source is positioned at the surface near the borehole.
D) It produces 3D images of strata near the borehole.
What is a key feature of Offset VSP?
A) It uses multiple sources arranged radially.
B) It provides imaging at half the offset distance.
C) The energy source is placed near the borehole.
D) It produces 3D images of salt dome margins.
Why is reservoir characterization crucial after discovering a petroleum reservoir?
A) To determine drilling locations without considering hydrocarbon volumes.
B) To calculate hydrocarbon reserves and determine the available oil and gas volume.
C) To minimize environmental regulations.
D) To reduce the need for geophysical surveys.
What is the purpose of developing an optimal production strategy in reservoir management?
A) To reduce seismic survey costs.
B) To drill the maximum number of wells.
C) To extract the maximum hydrocarbons at minimal cost.
D) To prioritize geological surveys over production.
What property of a reservoir grid cell represents the percentage of oil in the pore space?
A) Permeability
B) Petroleum Saturation
C) Porosity
D) Rock Density
How does a reservoir grid assist in production simulation?
A) By testing different extraction strategies, such as well spacing and production rates.
B) By eliminating uncertainties in reservoir properties.
C) By providing an alternative to using geological and petrophysical data.
D) By avoiding the need for updates during drilling operations.
Why is it important to determine the drive mechanism early in the life of a reservoir?
A) To identify the best locations for exploration drilling
B) To maximize recovery and improve reservoir management in its middle and later life
C) To eliminate the need for analyzing production data
D) To reduce the need for secondary recovery
How is the reservoir's drive mechanism identified?
A) Through analysis of production data such as reservoir pressure and fluid production ratios
B) By performing laboratory experiments on reservoir samples
C) By examining the geological structure of the reservoir
D) By conducting seismic surveys
What is the difference between oil shale extraction and shale oil extraction?
A) Horizontal wells with heaters for shale oil and horizontal wells with hydraulic fracturing for oil shales
B) Vertical wells with heaters for shale oil and vertical wells with hydraulic fracturing for oil shales
C) Horizontal wells with heaters for oil shales and horizontal wells with hydraulic fracturing for shale oil
D) Vertical wells with heaters for oil shales and horizontal wells with hydraulic fracturing for shale oil
What is the primary difference between tar sands and oil shales?
A) Tar sands are found in shallow reservoirs, while oil shales are found deeper underground.
B) Tar sands contain free heavy oil, while oil shales contain oil locked within kerogen.
C) Tar sands require heating for oil extraction, while oil shales do not.
D) Tar sands have lighter oil, while oil shales contain denser hydrocarbons.
