Petroleum Exam 2

Brent Crude

international crude oil marketer of light, sweet crude oil produced in the North Sea by Denmark, Norway, and UK, used as benchmark for crude oil prices, 2/3 of internationally traded crude oil

West Texas Intermediate WTI Crude

international crude oil marketer of very light and sweet crude oil produced in USA, benchmark for crude oil prices in US

Dubai/Oman Crude

international crude oil marketer of medium, sour crude oil produced in Middle East and used as benchmark for oil prices there

spot price

current price of petroleum product

future price

agreed upon price of a petroleum product at a specific time in the future

OPEC reference basket

overall average price of petroleum products produced by member countries, regardless of the quality of crude oil produced

sweet crude oil

crude oil with low sulfur content

sour crude oil

crude oil with high sulfur content

light crude oil

low density crude oil

heavy crude oil

high density crude oil

Strategic Petroleum Reserve SPR

world’s largest supply of emergency refined crude oil owned by the US created in order to combat issues with the petroleum supply chain and used as tool in foreign policy, controlled by Department of Energy

National Petroleum Reserve Alaska NPR-A

23 million acre property in Alaska that would be used for long-term, future unrefined crude oil extraction in case of an emergency, controlled by Bureau of Land Management

sequence stratigraphy

framework of genetically related stratigraphic facies geometries and their bounding surfaces used to determine their depositional setting

accommodation

the space available where a certain amount of sediment can be deposited into

sequence

fundamental unit, succession of strata bounded by unconformities or their correlative conformities

parasequence

smallest building blocks within sequences, usually representing upward-shallowing cycles

systems tracts

bodies of rock consisting of genetically related facies associations defined by their stacking pattern and position in a depositional sequence, subdivisions of a sequence representing different phases of a single sea level cycle

4 main systems tracts

HST, FSST, LST, TST

Highstand systems tract HST

sea level rise slows, sediment supply greater than accommodation, progradation basinwards, gravitational to progradational stacking pattern, followed by FSST

Lowstand systems tract LST

when sea level is lowest, sediment usually prograde outward into deeper, distal waters, rate of accommodation near rate of sedimentation, progradational to aggradational stacking patterns, followed by TST

Falling stage systems tract FSST

negative accommodation, degradational stacking pattern, falling sea level, shoreline moves seawards, formation of erosional unconformities

Transgressive systems tract TST

rapid sea level rise, shoreline retrogrades, accommodation rate is greater than sedimentation rate, retrogradational stacking patterns

bubble point

critical point

petroleum system

natural system that links an active or once active source rock to all the geologic elements and processes that are needed for hydrocarbon accumulation to exist

elements of a petroleum system

source rock, reservoir rock, seal rock, overburden rock

2 processes of petroleum systems

trap formation, the generation, migration, and accumulation of hydrocarbons

primary migration

movement of oil and gas through and out of fine grained source rock via diffusion and pressure-driven fluid flow

secondary migration

movement of oil and gas through wide pores in the carrier and reservoir rocks to the trap via vertically buoyancy forces that depend of density difference between water and petroleum

clastic reservoir

un/consolidated sands with various porosity, permeability, and some fractures

carbonate reservoirs

limestone and dolomite, fractures very important

reservoir rock properties

porosity, permeability, water saturation

stratigraphic trap

hydrocarbon trap that form from changes in rock type, pinch outs, unconformities, or other sedimentary features

structural trap

hydrocarbon traps that form in geological structures like faults and folds

isopach map

contour map showing true thickness of stratigraphic units by measuring thickness perpendicular to bedding places

isochore map

contour map showing the vertical thickness of stratigraphic units

CCUS

Carbon Capture, Utilization, and Storage, capture of carbon dioxide from atmosphere or other sources and uses it in products or stores underground

4 main storage areas for CO2

deep saline aquifers, depleted oil and gas fields, deep unmineable coal seams, mafic/ultramafic basalt formations

geothermal energy

renewable and cleaner energy source from geothermal heat in the earth

4 main characteristics of unconventional petroleum resources

low permeability/porosity, self-sourced, nano-pore system, high total organic carbon

unconventional resources

shale oil/gas, tight sands/carbonates, coal bed methane, oil sands/bitumen, oil shale

shale gas/oil

unconventional reservoir, hydrocarbons trapped in fine grained shale formations requiring fracking and horizontal drilling, Marcellus formation

tight sands/carbonates

unconventional reservoir with low permeability/porosity, requires fracking, Berea sandstone

oil shale

unconventional reservoir of shale containing immature organic kerogen, Green River formation

oil sands/bitumen

unconventional reservoir, mixture of bitumen, sand, clay, and water containing crude oil, shallow surface mining, Alberta

coal bed methane CBM

unconventional reservoir of natural gas (methane) within coal seams

low permeability/porosity

unconventional characteristic where rock fabric is too tight for fluids to flow freely, requires fracking

self-sourced

unconventional characteristic, reservoir rock is also source rock, oil and gas does not migrate

nano-pore system

unconventional characteristic, dominated by nanopore-throat systems

high total organic carbon TOC

unconventional characteristic, source rock contains at least 3% TOC