Access Restriction

Author Harris, A. J. L. ♦ Rowland, S. K.
Source CiteSeerX
Content type Text
File Format PDF
Subject Domain (in DDC) Computer science, information & general works ♦ Data processing & computer science
Subject Keyword Heat Loss ♦ Lava Flow Length ♦ Effusion Rate Control ♦ Flow Type ♦ Flow Length ♦ M3 S21 ♦ Cooling-limited Flow Length ♦ Flow Extension ♦ Minimal Insulation ♦ Effusion Rate ♦ Basalt Open Channel ♦ Thin Tube Roof ♦ Insulated Regime ♦ Core Cooling Rate ♦ Flow Core Cooling Rate ♦ Field Measurement ♦ Morphological Range ♦ Thick Crust Form ♦ Principal Influence ♦ Fundamental Role ♦ Several Kilometre ♦ Basalt Thick Tube Roof Insulate ♦ High Viscosity ♦ Hot Surface Crust
Abstract compositions and flow types, effusion rate (E) was the principal influence on flow length, sparking a series of studies into the volume and cooling limits on flow extension. We here review these works, as well as the role of heat loss in controlling flow length. We also explore the applicability of Walker’s idea to a larger compositional and morphological range. Heat loss plays a fundamental role in determining flow core cooling rates, thereby influencing cooling-limited flow length. Field measurements allow classification of four flow types with respect to heat loss. In this classification as we move from poorly insulated to well insulated regimes, decreased heat losses increase the length that a flow can extend for a given E, composition, morphology, or amount of cooling: (1) immature tube-contained, basalt – thin tube roofs provide minimal insulation, allowing cooling rates of c. 1022 8C s21 so that at low E, these flows extend only a few hundred metres; (2) poorly crusted, basalt – open channels with hot surface crusts also exhibit cooling rates of c. 1022 8C s21 so such flows extend a few kilometres at E, 1 m3 s21; (3) heavily crusted, dacite – heat losses are reduced when thick crusts form, reducing core cooling rates to c. 1024 8C s21 so these flows can potentially extend several kilometres even at low E and despite very high viscosities (109–1010 Pa s); (4) master tube-contained, basalt – thick tube roofs insulate
Educational Role Student ♦ Teacher
Age Range above 22 year
Educational Use Research
Education Level UG and PG ♦ Career/Technical Study