Joides Gas Hydrate Stability Zone Formula (Returns the base of the gas hydrate stability zone for a given water depth)

Joides_GHSZ_Formula.py

#!Python3

def joides(water_depth, base_water_temp, geothermal_gradient):
    """Returns the base of the gas hydrate stability zone for a given water depth

    Joides formula for calculating the base gas hydrate stability meters below sea floor. As per the publication:
    Ocean Drilling Program Guidelines for Pollution Prevention and Safety; JOIDES Journal, Volume 18, Special Issue
    No. 7, October 1992.
    A range of 1-2501 is used, as per studies, generally the maximum is 2000 meters below surface.


    Args:
        water_depth: The absolute value of the water depth in meters
        base_water_temp: Bottom water temperature in degrees celsius
        geothermal_gradient: Geothermal gradient in degrees celsius/kilometers
    """

    for z in range(1, 2501):
        a = math.log((10.17 * (water_depth + z)))
        if a > 9.355001:
            for z2 in range(1, 2500):
                a = math.log((10.17 * (water_depth + z2)))
                b = 46.74 - (10748.1 / (base_water_temp + ((z2 * geothermal_gradient) / 1000) + 273.15))
                if a < b:
                    return z2
        else:
            b = 38.53 - (8386.8 / ((base_water_temp + (z * geothermal_gradient / 1000)) + 273.15))
            if a < b:
                return z