Geoscience Reports
Summer 1984 No.4
Earthquake!
Probably one of the most terrifying experiences is to live through a
major earthquake. Unlike tornadoes, hurricanes, floods, or fires there is no realm of
relative safety that one can flee to during an earthquake.
What causes earthquakes? Can earthquakes be predicted? How can we
measure earthquakes? Why do some areas have earthquakes and others not? These questions
may be answered reasonably well for the other above-mentioned natural disasters; however,
earthquakes are different. To answer these questions, the scientist must be able to study,
in detail, the various factors involved in the process. It is this need for detail that
complicates the study of the earthquake.
The only direct observable data the scientist can acquire concerning
earthquakes is limited to the upper few tens of meters of the Earth's surface. Beyond this
point the scientists must rely on the unraveling of the tangled skein of records written
by seismographs.
Greek Word
The word seismograph comes from the Greek word seismos
which means earthquake. The study of earthquakes, 'Seismology,' did not have its formal
beginning until 1855 when L. Palmieri, of Italy, invented the first seismograph: a simple
horizontal pendulum which recorded the earth's movements in sand or on smoked paper. Even
many of today's sophisticated seismographs work on the pendulum principle. (See
"How-To- Department.'')
It is from the records of the seismograph that much is learned not only
about the strength and origin of an earthquake but also about the interior of the earth
itself.
To the untrained eye the tracing of the seismograph is just a bunch of
wiggly lines of varying spacing and height. Actually the waves, recorded by a seismograph,
can be divided into two classes: the surface waves or L waves and the waves that travel
through the body of the earth, the P waves and the S waves. See Fig. 1. It is the long or
L waves that we feel during an earthquake and it is the L waves that are also responsible
for the destruction. The L waves are also the largest of the waves recorded.
Push and Shake
One might think of the P and S waves as push and shake waves. The primary or P wave is similar in nature to the sound waves which are generated by the alternate compression and rarefaction in the medium through which it travels. The secondary or S wave is similar to the wave generated by the shaking of a tightly strung rope or clothesline in which the waves generated are at right angles to the direction of travel.
Waves
The L wave travels the slowest and the P wave travels the fastest.
Of the two body waves only the P wave travels through liquids.
It is the unequal speed at which the P and S waves travel that allow
one to determine the focus or epicenter of an earthquake. A single reading cannot pinpoint
the exact location of the epicenter. A single reading gives only a distance radius with no
direction vector. It takes a minimum of three different seismographic readings from three
different stations to determine the exact epicenter of the quake. See Fig. II
There are two basic ways to measure the intensity of an earthquake. The
first, and more subjective, is derived primarily from the effects on people and
structures. This type of measurement is the Mercalli Intensity Scale. As you can see, a
single earthquake may have many ratings depending upon the distance from the focus, types
of structures, etc.
The second and more familiar method of measuring earthquake intensity
is the Richter Scale of Magnitude. The Richter Scale is based upon the total amount of
energy released by the earthquake. Because the Richter Scale is logarithmic rather than
arithmetic an earthquake of magnitude 4.0 is not twice as great as an earthquake of 2.0
but rather 100 TIMES as great with the release of almost 1000 TIMES AS MUCH TOTAL ENERGY!
Figure I I I shows the relationship of energy and earthquake magnitude for the Richter
Scale.
Fig. III Richter Scale of Magnitude
Earthquake magnitude Approximate energy released
1.0 6 ounces of T.N.T. 1.5 2 pounds T.N.T. 2.0 13 pounds T.N.T. 2.5 63 pounds T.N.T. 3.0 397 pounds T.N.T. 3.5 1,990 pounds T.N.T. 4.0 6 tons T.N.T. 4.5 32 tons T.N.T. 5.0 199 tons T.N.T. 5.5 1,000 tons T.N.T. 6.0 6,270 tons T.N.T. 6.5 31,550 tons T.N.T. 7.0 199,000 tons T.N.T. 7.5 1,000,000 tons T.N.T. 8.0 6,270,000 tons T.N.T. 8.5 31,550,000 tons T.N.T. 9.0 199,000,000 tons T.N.T.
The specific causes of earthquakes still remain unclear. In a
general sense, earthquakes can be directly associated with plate tectonics (the movement
of large sections of the earth's crust, similar to that of sponges upon the surface of a
basin of water). The contact zone of two plates is called a fault (fracture) zone.
Movement along a fault may be horizontal, vertical or a combination of the two. Probably
the most widely known fault is the San Andreas Fault in California.
The San Andreas Fault is at the contact between the Pacific Plate and
the North American Plate. Movement along this fault is almost exclusively horizontal. Some
areas along the San Andreas Fault show a slow continual movement or creep. Other portions
of the San Andreas Fault show no signs of creep and are said to be locked up. The areas
which tend to creep generally have less severe earthquakes whereas the locked areas tend
to have more severe earthquakes. Both San Francisco and Los Angeles are located near
locked portions of the San Andreas Fault.
The cause of plate movements and the triggering mechanisms are still
unknown. Some geologists and geophysicists suggest a correlation between earthquakes and
sunspot activity while others suggest a correlation between earth tides or the phases of
the moon. And yet others say it is the wobble of the earth about its axis that causes
earthquakes, while another group suggests it is the earthquakes that cause the wobble. It
is safe to say nobody knows for sure, although plate movements seem to be the key.
Pacific Ocean
According to Putnam and Bassett (1971) earthquakes have a notable
concentration around the borders of the Pacific Ocean and westerly from its rim along the
line of the Himalayas and the mountains of the Middle East through to the Mediterranean.
Japan is the earthquake capital of the world followed closely by the islands of Indonesia,
New Zealand, the Philippines and the west coasts of North and South America.
Some regions, such as the great shield areas of every continent, are
virtually free from earthquakes (Putnam & Bassett 1971).
Without a complete understanding of the causes and mechanisms of
earthquakes, prediction with any accuracy ranges from difficult to impossible. Progress is
being made as to prediction of earthquakes but the science is still an infant!
Predictions
In order to assist with earthquake prediction scientists not only
monitor seismic activity but also the tilt of the earth about active faults, the release
of radon gas from fractured bedrock into deep water wells, and the changes of the magnetic
characteristics of the rocks near the fault. All of these tools are indirect methods used
to understand the nature and cause of earthquakes.
While one cannot prevent earthquakes or accurately predict when an
earthquake will occur, it is still possible to live reasonably safe in an active seismic
zone. Control of the type and manner of construction of commercial and residential
structures has greatly decreased the amount of damage resulting from an earthquake.
However, the greatest asset to damage control is for those living in an earthquake area to
be "Quake Aware."
Being ''Quake Aware'' is knowing how to prevent further destruction
after the earthquake. Know how to turn off the gas and electricity in order to prevent
fires. Few people realize that the major damage from the 1906 San Francisco earthquake was
more fire related than anything else. Also be aware of the human needs. Plan with your
family where you would meet after a devastating earthquake. Discuss with them conservation
of potable water and other necessities. Remember, the few minutes spent in preparation for
an earthquake may save your home as well as your life.
Further Reading
The following books and articles are intended to assist in further understanding the theme of the feature article ''Earthquake!''
Editorial: Towards a Better Understanding
The first introduction to a subject or idea often sets the tenor of
future relationship to and understanding of that subject. Often this introduction goes
unnoticed by everyone except the individual with the questioning mind.
As educators we are more aware of the questioning mind and the need for
accurate information. And yet, the parents' awareness is often keener than that of the
teachers because Johnny comes home and says "My teacher said ... and teacher is
right!"
Teacher Right
The statement, "My teacher is right, places a tremendous
responsibility on the teacher. How can teacher always "be right"? Realistically
it is impossible to know and understand every subject. However, it is possible to be aware
of some of the potential areas of questioning for a given grade level, and hence to have
accurate information for that subject. The depth of subject knowledge may not be great,
but, if accurate, the introduction to that subject will, more often than not, be
favorable. It is towards this end that Geoscience Reports has changed its format and
focus.
Geoscience Reports is therefore dedicated to you, the classroom
teacher. Like you, we do not have all of the answers either, but, unlike you, we may have
the time to find the answers and share them with others.
Need Input
In order for this format and focus to be successful, we at
Geoscience need your input. If you are troubled with a given science subject area, feel
free to use us as a resource agency. We will try to answer all inquiries either privately
or in Geoscience Reports.
In closing I would like to share the following statement, from Ellen G.
White, on the type of science that God approves of: "God is the author of science.
Scientific research opens to the mind vast fields of thought and information, enabling us
to see God in His created works. Ignorance may try to support skepticism, true science
contributes fresh evidences of the wisdom and power of God. Rightly understood, science
and the written word agree, and each sheds light on the other. Together they lead us to
God by teaching us something of the wise and beneficent laws through which He works'' CT
426.
BRISCO
The GRI staff makes many public presentations in seminars,
classrooms, conferences, church groups, etc. Last year more than 70 public presentations
were given by the five scientists of the Institute.
The Colorado Springs area provided a pleasant setting for the latest
meeting of the Biblical Research Institute Science Council (BRISCO). Sponsored by the
Biblical Research Institute of the General Conference, BRISCO consists mainly of
Seventh-day Adventist scientists and theologians who meet annually in a locality of
geological or biological significance to study issues arising between scientific
interpretations and the Bible. BRISCO has never received much publicity, partly because it
is a working committee instead of a platform for the promulgation of personal
interpretations.
Fossil Beds
The Colorado Springs area was selected because of its Florissant
fossil beds which contain a number of large, petrified, upright trees along with a rich
variety of extremely well-preserved leaves, insects, etc. The group also examined
intriguing clastic dikes found in the Woodland Park area. These dikes have the potential
of placing some serious constraints on the amount of time allowed for the geologic time
scale.
In addition to the field work, the group spent about two of the four
days of the August meeting presenting and discussing papers of scientific and theological
concerns to the Seventh-day Adventist Church. In addition to general papers, a portion of
each BRISCO meeting is devoted to a special topic which is selected at the previous
meeting. For this meeting the special topic was catastrophic models and evidence for the
flood.
Ground work was laid for the presentation of a symposium volume that
will include some of the noteworthy findings and discussions of this committee. It will
probably take several summers before this symposium volume is published.
OVERSEAS OUTREACH:
Coupled with the increasing educational standard of most nations is
the exposure of their populations to evolutionary theory as an explanation of origins.
With this increased worldwide exposure the need to present a scientifically sound creation
theory and to answer questions concerning evolution is arising in the world church. To
meet these needs plans for closer contact between the Geoscience Research Institute and
designated Adventist scientists and educators in overseas divisions are being formulated.
Individuals with training in science or interest in creation/evolution
problems will be given opportunities to participate in field conferences in North America
and to spend time at the Institute in Loma Linda. Useful materials on creationism will be
provided them for circulation within their divisions. It is hoped that some of this
material will be translated into local languages.
A European field conference was conducted in the summer of 1981 and
another is scheduled for this summer. Approximately 50 Adventist teachers and
administrators have or will be involved in each of these conferences. Tentative plans are
being developed for future conferences in other overseas areas.
GRI ANNOUNCES RESEARCH GRANT AWARDS:
Research grants totaling $20,970 were awarded to 9 individuals for 1984. Each year GRI accepts application for proposed research centered around creationism. The grants are open to individuals in academic institutions, and the spectrum of possible research areas is quite broad. The award grants represent newly initiated work as well as funding for continuing studies. This year five of the awardees were graduate students working towards, advanced degrees. The list of recipients are:
M. Arct Tree Rings and Earth History (LLU) A. Chadwick Paleocurrents in the Geologic Record (Southwestern) C. Clausen The Development of a Method for Growth Increment Analysis Using Computer Image Processing Techniques (LLU) J. Gibson Chromosome Evolution in North American Ground Squirrels of the Genus Spermophilus (LLU) C. Haller Preliminary Investigations of Growth-Lines in Vertebrae, Otoliths, Fin Rays, and Scales of Fossil Fish, Green River Formation WY (LLU) J. Hayward How Do Bird Eggs Become Fossils? A Taphonomic Study (Union) J.-L. Lienard Effects of Depth and Light Regime on Coral Growth Ridges (LLU) L. Schremp Mammalian Biostratigraphy of the Type Huaquerian of South America (LLU) D. Woodland The Use of Biochemical Techniques to Investigate the Biogeography and Speciation Interrelationships of North American Species of Urtica (Nettles) (Andrews)
Although the above represents the physical and biological sciences, grant proposals in the history of science, biblical studies or philosophy would also receive consideration. Application DEADLINE is February 15, 1985 for funding by June 1, 1985. NOTE: There is only ONE (1) funding period for 1985! Potential applicants should contact C. L. Webster at the GRI for further information.
Publications . . .
ORIGIN BY DESIGN
Origin By Design, new name for a major revision of Creation:
Accident or Design, came off the press in January. This 500-page book, authored by
Harold G. Coffin and Robert H. Brown both from Geoscience Research Institute with
assistance from others, is one of the most comprehensive volumes on creationism available
today. It is published by the Review and Herald Publishing Association and is available in
Adventist Book Centers around the country.
Some of the changes in the second edition involve expansion of the
section on evidences of the Flood, addition of chapters on the Yellowstone Petrified
Forests and evidences for a youthful earth, and enlarged treatment of the theory of
evolution and radioactive dating methods. The first edition was prepared for an Adventist
readership, whereas the second edition is suitable for the general public.
ORIGINS
The first issue of the 1983 edition of Origins displayed a new change in format - the addition of a color cover. Using a picture displaying upright floating logs on Spirit Lake near Mount St. Helens, the advent of color seemed an appropriate way of celebrating the tenth anniversary of publication. Although the use of color will at first be limited to the cover, changes in paper type and ink used internally in the journal will eventually allow use of color inside the journal as well. This new capacity should expand both the usefulness and impact of this publication.
SPANISH ORIGINS
A Spanish journal entitled Cienca de los Origenes,
concerned with creation and science news items relevant to the creation/evolution
controversy, is being sent to Seventh-day Adventist students and schools in Central and
South America. Three issues are produced each year by Dr. David Rhys under the auspices of
the Geoscience Research Institute staff.
Costs of printing and mailing are being borne by the Geoscience
Research Institute and the Central and South American Divisions as a service to
Spanish-reading Adventists who do not have a large library of creation publications to
consult.
Dr. Rhys, well known as an educator in Latin America, is translating
into Spanish articles and news items that appear in Origins and other English
publications. Letters received from recipients of the paper indicate that it is filling a
need and is appreciated.
GRI Staff Research
TKACHUCK
Using high performance liquid chromatography (hplc) Dr. Richard
Tkachuck began a series of studies examining the metabolic pathways of glucose metabolism
in tapeworms found near the Walla Walla College marine laboratory near Rosario,
Washington. The tapeworm has been defined in evolutionary thought as primitive in that it
has only one segment. By comparing its metabolic pathways with other orders of tapeworms,
it is hoped to determine how parasites may have evolved.
In addition to these studies, Tkachuck also collaborated with Drs.
William Hughes of Andrews University and Gary Rosenburg of the University of Indiana in
their studies of the development of growth lines in brachiopods. Growth lines are believed
to form when organic acid production increases during anaerobic conditions. Using hplc,
Tkachuck was able to determine the kinds of acids and their concentrations.
The summer of 1984 will again find Tkachuck at the marine lab where the
above work will be continued.
WEBSTER
Utilizing the sensitivity of spark source mass spectrometry (ssms) Dr. Clyde Webster is working on a baseline study of trace element profiles in Hawaiian basalts. Once verification of the technique of using trace element profiles to identify individual historic basalt flows is established, the principal research area will switch from Hawaii to the fossil forests of Yellowstone. The objective of the Yellowstone study will be to determine the minimum number of flows involved in the petrified forest.
News Notes:
Field Conferences
Unlike Gershwin's summer where the ''livin' is easy,'' the summers
at the Geoscience Research Institute (GRI) are very busy!
The summer and early fall of '83 saw the staff of GRI host two field
conferences for SDA church leaders. The first group (July 11 -20) consisted of members of
the Adventist Health System, Eastern and Middle America and the Mid-American Union.
President Neal C. Wilson and other top church leaders, including a number of overseas
division personnel on their way to Annual Council. comprised the second group
(September13-28).
The question of the authenticity of the Bible becomes more salient as
scientists continue to develop a paradigm of long ages for the history of life on earth.
The participants of these conferences became better acquainted with the scientific
explanations that challenge the authority of the Bible. They also witnessed scientific
evidence that supports the inspired record of origins and the flood. The question of
origins is most important to the Seventh-day Adventist Church because the keeping of the
seventh-day Sabbath is based on a literal six-day creation week, not a creation or
evolution process taking thousands or millions of years. The localities selected for these
field conferences were in the western United States which has outstanding examples of the
geologic processes that demarcate the past history of our world. Included were:
Both problems and potential solutions to various questions were
discussed, pondered, and rediscussed by the group.
Scientists and theologians from SDA educational institutions along with
the GRI staff complemented the field studies with a wide variety of interesting
intellectual presentations. The daily pursuits were enriched with outstanding devotional
periods which added balance to an intensive schedule.
The participants repeatedly expressed gratitude for the opportunity to
learn and discuss the great issues of origins. Thankfulness was also mentioned for the
information regarding the early history of the world that is available to us from inspired
writers.
UC Riverside
Dr. Ariel A. Roth spoke to an advanced geology class at the
University of California, Riverside campus about the concepts of and evidence for a
worldwide flood. Arguments in support of a worldwide flood included: 1.) The unusually
widespread distribution of sediment and fossil types as would be expected in a worldwide
catastrophe, 2.) the abundance of underwater turbidite types of sediments on the
continents, 3.) the paucity of erosional features at so-called long time gaps suggesting
the time gaps never occurred, 4.) the abundance of marine types of deposits on the
continent, 5.) spores of plants occurring much earlier in the fossil record than the
plants themselves, and 6.) sedimentary intrusions that suggest much shorter periods for
the standard geologic time scale.
The ensuing lengthy amicable and open discussion which followed
concerned itself at first with the evidence of the flood. The discussion then turned
towards the relation of God to science and the conflict that is sometimes postulated
between God and science. In the opinion of Dr. Roth there need not be such a conflict,
since science can address itself to observing the consistency God has created in nature.
Such consistency can be used to establish explanations about nature.
Call For Papers ...
Do you have a restless pencil or a lonely sheet of paper? If so, why
not try your hand at putting the two together and writing a feature article for Geoscience
Reports, or share with others your experiences in the How-To Department?!
Feature articles should be 750 to 1,000 words in length. The subject
matter should be on a science topic of general interest to teachers (K-12), with emphasis
on understanding God's created works. A list of further reading should be included with
the feature article, whenever possible.
The How-To Department should be singular in purpose and include concise
directions and illustrations. Topics should be readily adaptable for in-class construction
and/or demonstration.
If feature articles and how-to's are not your strong suit, why not try
an editorial?! Here would be your chance to share with others your concerns.
All submissions are to be typewritten and double spaced. All authors
should be identified by name, place of employment, grade level, and date, at the end of
the article. Submit all articles and inquiries to:
Editor, Geoscience Reports
Geoscience Research Institute
Loma Linda University
Loma Linda, CA 92350
HOW-TO DEPARTMENT: Seismograph
The earth can be likened to a bowl of jello which vibrates over the whole surface when
touched at any point. Instruments used to record earth vibrations are called seismographs,
seismos being Greek for earthquake.
A simple seismograph can be constructed with everyday material which
will record strong earth vibrations or local vibrations such as passing trucks, jumping on
the floor, etc.
MATERIALS LIST
Use C-Clamps
Secure the plywood base to a heavy table by means of the C-clamps.
To one end of the base fasten the flange by means of the wood screws, as shown in Fig. 1.
About 5" above the threaded end of the pipe, drill a small dimple in the pipe. DO NOT
drill all the way through. Screw the pipe securely into the flange. Next, take the
20" length of 1/4" rod and file both ends to a point. Fit one end into the
dimple in the pipe and suspend the rod in a horizontal position by connecting its far end
to the top of the pipe with the No. 14 steel wire. Attach to the horizontal rod sash
weights or bricks with wire or tape. This completes the horizontal pendulum of the
seismograph.
The recording device for the seismograph is fashioned from a
spring-wound alarm clock. Remove the minute hand and glue the 4"disk to the hour
hand. Make sure the disk is centered as much as possible. Carefully soot the disk with the
candle, taking precautions not to ignite the disk. This completes the recorder.
After construction, position the seismograph in a N-S or E-W direction.
Once the pendulum has stopped swinging place the clock so that the point of the metal rod
just touches the soot on the disk at about the nine o'clock position. The rod will now
register local vibrations on the dial versus time.
Disks may be changed if one wants to keep a record or resooted for the
next day. After recording vibrations in one direction for a couple of days, switch
directions and compare the two records in order to determine the most ''active'' trend.
Good luck! And may all your vibrations be small!!
Geoscience Reports Summer 1984 No. 4
Editor --- Clyde L. Webster
Associate Editor --- Katherine Ching
Subscription requests, correspondence, and notices of change of address should be sent to: Geoscience Reports, Geoscience Research Institute, Loma Linda University, Loma Linda, CA 92350.
Geoscience Reports is a newsletter published by the Geoscience Research Institute to present current happenings at the Institute as well as articles of general interest which deal with creation/evolution issues for primary and secondary school teachers. The views expressed are those of the authors and not necessarily those of the Institute.
Staff of the Institute are: Ariel A. Roth - Director, Robert H. Brown, Katherine Ching, Harold G. Coffin, Richard D. Tkachuck, and Clyde L. Webster.