Page 31 - Caldera Volcanism Analysis, Modelling and Response

6 Fidel Costa

in time. sources
discussed Magma cooling (Ky 1 ) e residence Data

systems rate n.d. (0.1–2) 10 2 n.d. 5 10 4 n.d. (0.8–1) 10 3 n.d. (0.2–2) 10 3 (0.6–2.3) 10 4 (0.4–4.5) 10 4 (0.2–1) 10 3 n.d. n.d. n.d. (0.3–3) 10 3 and volume time. residence

the the
for erupted over
eruptions Magma production (km 3 y 1 ) d 7.5 10 3 –1.3 10 1 (0.2–1) 10 2 10 2 4 10 3 (0.5–6) 10 2 or K–Ar or 14 C methods. c Calculated from the time difference between the eruption age d Ratio of 1995)

silicic rate n.d. (1–4) 10 3 (1–4) 10 3 1.8 10 2 3.3 10 4 (2–5) 10 2 1.7 10 3 (1–3) 10 2 (0.2–1) n.d. n.d. ca U–Th–Pb). Sack, and

caldera-forming residence time c 70 ky 250 ky to 240 ky to 160 ky to 160–170 ky 77–234 ky 50–390 ky 500–750 ky 80–360 ky (perhaps 900 ky) Rb–Sr, Ghiorso MELTS,

major Magma n.d. to 4 9–50 ky Up Up Up 180 ky 19–57 ky n.d. n.d. (e.g., by

of age b temperatures (determined
rates Eruption 26.5 ka 320–340 ka 1.21 Ma 161 ka 600 ka 1.3 Ma 2.0 Ma 760 ka 1.2 Ma 1.6 Ma ca.4 Ma 28 Ma closure

magmatic 7.0 ka 62 ka 75 ka obtained by 40 Ar/ 39 Ar, higher temperature

and (km 3 ) 100 300–1000 300–1000 with liquidus
times order. V ol a 50 530 ca 2800 60 1000 280 2500 600 250 400 2700 5000 clocks the and determined.

residence geochronological ash Mazama radioactive other pre-eruptive n.d.=not

characteristics, by unit and Tuff Toba Tuff Plateau Creek Falls Bandelier Bandelier Toconao and Canyon Volumes in dense rock equivalent. b This is the age by obtained the between text. the in

of organised Member or Wineglass Oruanui Rotoiti Whakamaru Ongatiti Y oungest Kos Lava Mesa Huckleberry Bishop Upper Lower Atana Fish deposit difference and 3–8
Summary Volcanic the of the using Tables in

1 manuscript Lake Crater Taupo Zone Y ellowstone Valley Toledo Pacana Garita a Vol ¼ age the e Calculated found
Table the Toba Kos Long Valles La La Note: and be can