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Geysers of the World   

Geysers of Yellowstone   



Transactions XI

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Terra Cotta Complex

Mike Keller



         Starting in 1989, the author began  observing and documenting the behavior of the geysers within the Terra Cotta Complex.  During this time a total of 6 independent geysers and a total of 13 overall erupting vents were observed.  The following article will discuss the observations made by the author over the past 20 years and provide a quick historical summary of the activity of the geysers in this area.



West Triplet and Rift Geysers, Grand Group,

Upper Geyser Basin, 2003-2008

Vicki Whitledge, Ryan Frank and James Hollman



         West Triplet and Rift Geysers in the Grand Group, Upper Geyser Basin, have been electronically monitored for a number of years.  The eruptions times, from 2003 through 2008, derived from the electronic data, are analyzed. Basic descriptive statistics on these data and a quantitative description of the relationship between West Triplet and Rift geysers are given.



Events at the Daisy Geyser Complex,

September 8, 1997

Andrew Hafner


         On September 8, 1997, the author had the opportunity to observer a sequence of eruptive events in the Daisy Geyser Complex in Yellowstone’s Upper Geyser Basin. Following a short introduction to Splendid Geyser’s activity in 1996 and 1997, this article briefly describes the types of events that could occur while Splendid was in an active series and describes the events of September 8, 1997 in detail.



Fan and Mortar:

A Summary of the 2000-2005 Active Phase

and Details from 2004 and 2005

Tara Cross


        The active cycle of Fan and Mortar from early 2000 to August 2005 was one of the best on record for the geysers. Fan and Mortar’s behavior during this period is summarized, with more detailed observations given for 2004 and 2005.



Ragged and Jagged Springs at

Black Sand Basin: July 2008

Stephen Michael Gryc


         Ragged Spring and the unofficially named Jagged Spring erupt together. During the summer of 2008, eruptions were frequent with some bursts from Ragged reaching a height of 7 feet while bursts from Jagged occasionally reached 25 feet. This paper describes an eruption sequence typical of those seen on July 4, 5 and 6 and provides a summary of data from 173 eruptions logged during nearly 8 hours of observation.



Green Spring Erupts: July 6, 2008

Stephen Michael Gryc



            Green Spring in Black Sand Basin has been known to have infrequent episodes as a geyser. In July of 2008 the author witnessed what may have been the only eruption reported that summer. The characteristics and timing of that single eruption are described.



Black Diamond Pool Erupts, May 17, 2009

Photos Reprinted with Permission from the National Park Service

(photographer unknown), Account Recap by Tara Cross.



Additional Information About the 1985

Eruptive Episode of Excelsior Geyser

Lynn Stephens



       Mary Ann Moss’s observations and Mike Keller’s personal recollections of the September 1985 activity of Excelsior Geyser were printed in Transactions X. This article supplements their personal accounts and observations. Roderick (Rick) A. Hutchinson’s report, “Rejuvenation of Excelsior Geyser,” prepared on September 18, 1985, is included in this article. The article also includes correspondence between Hutchinson and Daryl Lafferty, a park visitor who first reported the eruptions, and comments from Rocco Paperiello about his observations of some of the 1985 eruptions.1 Reports of possible activity in 1946 and 1952 are also discussed.



Wild Phase Activity by Great Fountain Geyser

T. Scott Bryan



       On relatively infrequent occasions, Great Fountain Geyser undergoes what is referred to as “wild phase” activity, in which it erupts with frequent bursts for total durations longer than two days. The wild phase that started on June 4, 2008, was perhaps the most closely observed of these events from start-to-finish and is described along with an historical perspective.



Summary and Analysis of a

National Park Service Geyser Activity Report

for Summer 1919

Vicki Whitledge



         Geyser reports from 1900 to 1920 are scarce. (Keller 2002, 27) The advent of Google Books (books.google.com) has made the search for older publications about geysers easier than in the past.  A document from 1919 titled “Reports of the Department of the Interior” by Franklin K. Lane was recently found on Google Books. This report is unique for the period in that it contains a table of geyser eruption times from the summer of 1919 and limited descriptions of geyser activity. This article presents the material relating to geysers in the Lane report along with analysis and commentary by the author based on comparisons current observations of geyser activity and information from other historical records.



The Land of Wonders:

Promenade in North America’s National Park

by Belgian travel writer Jules Leclercq
Observations of Yellowstone geysers

from a nineteenth-century account of a visit to the Park.
Translated from the French book,
La Terre des Merveilles, and

annotated by Janet Chapple and Suzanne Cane



            Jules Joseph Leclercq, Belgian lawyer, world traveler, and president of the Royal Geographical Society of Belgium, visited Yellowstone Park in 1883 and published his lively account three years later. Until the twenty-first century, the only known partial translation of The Land of Wonders into English was unpublished and in the hands of Yellowstone Park Historian, Lee H. Whittlesey. For GOSA Transactions readers, the translators present a new translation of the six chapters Leclercq devotes to his unique observations of the geyser basins.


 The Activity of Several Backcountry Geysers

as Determined Through Automatic

Data Logger Studies

Jeff Cross, Carlton Cross and Tara Cross



From 1998 through 2009, several geysers in the Shoshone, Heart Lake, Lone Star and Gibbon Geyser Basins were monitored through the use of automatic data loggers.  Data obtained via loggers is combined with data from literature sources and visual observations to describe the recent eruptive history of Glade Geyser, Double Geyser, Frill Spring, The Hydra, Buried Geyser, Phoenix Geyser and Oblique Geyser.



A Model of a Geyser that Erupts in Series


Jeff Cross


       A model geyser, having two reservoirs and erupting in series with several minor eruptions preceding a single major eruption, is described. Minor eruptions originated in the upper reservoir and major eruptions originated in the lower reservoir. The mechanism by which the series occurs is described. Interactions between the two reservoirs constrained the major eruption to begin during specific parts of the minor eruption cycle.


Periodicity of an Underwater Geyser

Varying with Tide

Masayuki Nagao

Institute of Geology and Geoinformation,

National Institute of Advanced Industrial Science and Technology (AIST),

AIST Central 7, Tsukuba, Ibaraki 305-8567, Japan



Yasuo Furushima

Institute of Biogeosciences,
Japan Agency for Marine-Earth Science and Technology   (JAMSTEC), 2-15 Natsushima-cho Yokosuka 237-0061 JAPAN

Atsushi Suzuki

Institute of Geology and Geoinformation,

National Institute of Advanced Industrial Science and Technology (AIST),
AIST Central 7, Tsukuba, Ibaraki 305-8567, Japan


Hiroyuki Yamamoto
Tadashi Maruyama

Institute of Biogeosciences,
Japan Agency for Marine-Earth Science and Technology   (JAMSTEC), 2-15 Natsushima-cho Yokosuka 237-0061 JAPAN



         The periodicity of an underwater geyser in the Taketomi submarine hot spring in Yaeyama archipelago, Japan, has been investigated for the first time by Furushima et al. (Marine Technology Society Journal, 43(3), 13-22, 2009). After conducting a time-series analysis of the upward velocity using an acoustic current meter, they concluded the time cycle of the geyser responded to the tide. The time cycles of the geyser at high and low tide were 66 s and 41 s, respectively. They also considered the relationship between the temperatures of the heat source and the recharge water, based on the vertical tube theory (Yuhara and Seno, 1969), a physics model of an onshore geyser. Assuming that the heated domain was just below the sea floor, and that the temperature of the heat source (Q) was over 200 ºC, they calculated that a recharge water temperature (q0) of 117.96 ºC could sustain the observed time cycles at high and low tide. However, the relationship between Q and q0 can vary according to the underground depth of the heated domain (H). In this study we obtained a time series of H from the averaged integration of upward flux per each eruption, after assuming that the cross-sectional area of the vertical tube had a constant value throughout the vertical direction. Results showed that H ranged from 6.6 m to 14.9 m with an average of 9.9 m. With some exceptions, we could regard H as a constant value of 10 m, as the tide changed from high to low. Again according to the vertical tube theory, this new H of 10 m indicated that at least the Q must be above the boiling point of the recharge water (Q>133.82 °C), and to stably sustain the cycles, the conditions of Q > 200 °C and q0®q0s=130.57 °C are desirable. These estimations of Q were consistent with the previous estimations of the “deep underground water temperature” at the Taketomi Submarine Hot Spring, which ranged from 160 to 200 ˚C as reported by Kaneshima et al. (1983), Kimura et al. (1985) and Oomori (1987).   



The Effect of a Constriction on the

Function of a Model Geyser

Jeff Cross and Ron Keam



      It is sometimes suggested that a geyser can erupt periodically if and only if its plumbing system contains a constriction. In this paper, we examine the effect that the presence and absence of a constriction has on the function of a model geyser. One of us (J.C.) has shown by experiment that a model geyser that lacks a constriction can erupt periodically. We propose an explanation for this observation. We also describe a physical model that explains how a constriction, if present, can help initiate the eruption process in a geyser.


Addendum to The GOSA Transactions

Volume 10, 2008

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