Table 3.

The actual flow velocity of fissure water fitted using the equation limit method.

Type of groundwater	Depth (m)	Duration (m)	Model	Curve-fitting equation	Va (μm/s)	R2
Water in sand layer	13	2310	Logistic	V(t) = 307.35 + 146.42/(1 + (t/11.25)0.81)	307.35	0.99
	14	1970	Gauss	V(t) = 434.49 + 16,264/(228.36 $\sqrt{\frac{\pi }{2}}$ e−2((t−313.52)/52155)	434.49	0.99
	15	2900	Boltzmann	V(t) = 497 + 22.44/(1 + e((t−843.51)/112.96))	497.00	1
Fissure water in vesicular basalts	21	2320	ExpAssoc	v(t) = 442.33(1 − e−x/17.45) + 69.85(1 − e−x/734.92) − 138.21	373.97	0.99
	23	2260	ExpDec1	v(t) = 347.65–240.42e−t/25.06	347.65	0.93
	25	1630	ExpDec1	v(t) = 340.04–72.77e−t/353.85	340.04	0.83
	27	1980	ExpDec2	v(t) = 367.52 + 30.64e−t/1109–131.76e−t/45.05	367.52	0.96
	29	2100	Logistic	v(t) = 390.39–30.56/(1 + (t/506.89)3.23)	390.39	0.92
	30	6260	Logistic	v(t) = 453.35–65.46/(1 + (t/1328.82)1.91)	453.35	0.94
Fissure water in granites	120	560	ExpDec1	v(t) = 88.17 + 714.34e−t/13.18	88.17	0.83
	131	680	Gauss	v(t) = 230.52 + (33,980/(266(pi/2)0.5)e−2((t−225)/266)^2	230.52	0.98
	141	770	ExpAssoc	v(t) = 390.94–2544(1 − e−t/100.72) + 2410 (1 − e−t/105.5)	256.66	0.99
	228	1810	ExpAssoc	v(t) = 506.61–397.76(1 − e−t/38.81) + 122.25 (1 − e−t/2599.8)	285.10	0.89
	236	810	ExpDec1	v(t) = 73.69 + 158.01e−t/89.88	73.69	0.80
Fissure water in limestone	134	6000	ExpDec1	v(t) = 364.50 + 122.04e−t/125.5	364.50	1
	134	1700	ExpDec2	v(t) = 335.08–576.43e−t/28.8 + 87.56e−t/415.02	335.08	0.99
	134	26,800	Logistic	v(t) = 361.16 + 420.25/(1 + (t/39.34)6.98)	361.16	1
	120	3430	Logistic	v(t) = 220.21 + 217.20/(1 + (t/51.72)1.22)	220.21	1
Fissure water in schists	129	2750	ExpDec1	v(t) = 267.21 + 51.46e−t/181.21	267.18	1
	129	920	ExpDec1	v(t) = 229.33 + 141.35e−t/69.91	229.33	1