Back to front-page . Last updated: Feb 2006.

Useful Conversions

First text.

Enter a figure in any of the boxes & click "Calculate".

Distance Conversion Calculator
Meters Inches Feet Yards Miles Kilometres Fathoms

Area Conversion Calculator
Hectare Acres Sq. Kms. Sq. miles

According to Peter Rose (2001; AAPG Methods in Exploration Series, 12, p.20), the hydrocarbon recovery factor [HRF] for a reservoir should range from 100 bbls / acre-ft (very tight -borderline economic) to 1,200 bbls / acre-ft (top, world class reservoir) for oil, and range 125 mcf / acre-ft to 2,000 mcf / acre-ft for gas.


Mud density units
Pounds per
gallon
Pounds per
cu.ft
SG
Mud density and pressure
Pounds per
gallon
Depth
in metres
psi produced

Enter drilling mud weight in ppg and the depth (=height of fluid column, so depth KB or flow line) and the result is the downhole pressure of the mud for a static hole.


A leak-off test to MW equivalent
Leak-off
psi
Depth
in metres
MW equiv
in ppg

Enter Leak-off test (LOT) pressure in psi and the depth (=height of fluid column, so depth KB or BOP rams) and the result is the mud-weight roughly equal to the downhole fracture pressure.


Hydrocarbon Quantity Conversion Calculator
Barrels Gallons
(U.S.)
Gallons
(Imper.)
Cubic
Metres
Cubic
Feet
Met. tons
of oil
approx.
BOE
Cu.ft. gas
(MM)
BTUs
(millions)

Geothermal gradients
Degrees F
per 100ft
Degrees F
per100m
Degrees C
per 100ft
Degrees C
per 100m
Degrees C
per km

Sonic ITT to seismic velocities
microseconds
per foot
Metres
per second
feet
per second

So, for a seismic reflector at 1 seconds two way time (TWT; = 0.5 sec. one way time), and a sonic log averaging 120 microseconds per foot, the reflector would be very roughly 1270 meters deep. A crude rule of thumb in young Tertiary mudstones; the first second is very roughly a kilometer deep. After that, increasing rock velocities mean significantly greater depths than 2 kms at 2 seconds TWT

At the moment the table above only works one-way: from sonic log derived microseconds (µsecs) per foot to seismic one-way velocities.
Later this will be a reversible formula.


Also in the planning stage are conversion tables for bottom hole temperature [BHT] corrections based on Horner plots and single temperature measurements.