`estimate_formation_head` takes a vector of transmissivity and a vector of associated blended head measurements. The formation head is then determined as each interval is added. The transmissivity and blended head values should be ordered so that the monitoring interval is incrementally increased with each value. An example application would be the FLUTe reverse head methodology

estimate_formation_head(transmissivity, blended)

Arguments

transmissivity

the transmissivity distribution for each interval

blended

the blended head value

Value

a single value of the blended head

Details

`estimate_formation_head` calculates the formation head using the following formula:

$$^fh_i = \frac{\sum\limits_{i=1}^{i} \Delta T_i (^bh_i - ^fh_i)}{T_i} + ^bh_1$$

where:

* \(h_{blended}\) is the blended head in the well * \(\Delta T_i\) is the difference in transmissivity between increasingly larger interval. * \(^fh_i\) is the formation head of the newly exposed interval * \(^bh_i\) is the blended head of the increasingly larger interval * \(^bh_1\) is the blended head of the first interval * \(i\) is the interval number

References

Keller, C. (2017). A New Rapid Method for Measuring the Vertical Head Profile. Groundwater, 55(2), 244-254.

See also

Examples

transmissivity <- abs(rnorm(10, sd = 100)) # random T distribution cumulative_transmissivity <- cumsum(transmissivity) head <- sort(rnorm(10)) # decreasing head with depth formation_head <- estimate_formation_head(cumulative_transmissivity, head) estimate_blended_head(transmissivity[1:3], formation_head[1:3])
#> [1] -0.2792372