Geological Field Mapping in the UC Berkeley

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Geological Field Mapping in the UC Berkeley Curriculum
Motivation: The practice of earth science in the field is undergoing a revolution in digital
technology. With new Space Age 21st century technology combining Global Positioning Systems
(GPS) with Geographic Information Systems (GIS) in real-time outdoors, comes a great
opportunity for advancing instruction of undergraduates. By better equipping students for
scientific participation in a global context with the tools of their Age, they will be capable of
identifying and solving important new questions relevant to society in a timely manner making
full use of the information technology available.
Retention of Traditional Methods: We view the challenge of fulfilling this opportunity in
implementing the new digital technology effectively. This is not a matter of simply replacing
traditional methods entirely with digital electronic tools, but rather introducing new digital
methods and cost effective instrumentation that increase the overall productivity of earth
scientists in the field. We have found it imperative to start our field first geology course using
traditional topographic-based mapping using colored pencils and Brunton compasses. Only after
these methods have been mastered do we introduce digital mapping hardware and software.
High-tech instrumentation gets in the way of learning basic field skills of locating using
topographic maps, rock description, stratigraphy, use of a field book, structural measurements,
mapping outcrops, contacts, and formational infill. Our educational approach at UC Berkeley
enables students to use both traditional and digital methods to their greatest advantage rather than
disable skills that have for two centuries been the hallmark of field earth science. Topographic
map reading and positioning remain essential skills. GPS offers revolutionary advantages, but an
informed user of GPS is fully aware that there are places such as deep canyons where a GPS
does not function or may given erroneous results yet the need to map remains. Naivete in
believing any result from a computer is soon overcome in the field if a mapper remains fully
aware of their surroundings by independent means. Indiscriminant belief in technology must be
overcome through the field experience that blends the best practice from traditional and digital
methods.
Change in our Department’s Name: Like many geo-science departments across the US, the
faculty at Cal decided to broaden the scope of our activities and transform ourselves from a
Geology and Geophysics Department to Earth and Planetary Science. As part of our instructional
reform attending this change in focus, we found that the key element in modernizing field
instruction so that it remained an essential part of the new Earth and Planetary Science
curriculum was to focus on visibly active, dynamic global processes including climate change,
sea level fluctuations, and regionally-correlative processes in general. A second goal was to
support a telescoping “Google Earth” type synoptic view of the earth while conducting mapping
at scales appropriate for a given study using digital technology. In this context, the natural home
of field studies is in learning to perceive the geological record as a way of understanding such
dynamic processes trough time and space using digital and information technology of our day
not the paper maps of the past century. Earth scientists are now expected to become futurists.
Besides teaching traditional mapping and map reading skills, we need to teach in such a way that
the benefits are dramatically magnified beyond the scope of the local area and the age(s) of the
processes archived in the local geology. Field work then serves instead an integrative educational
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role not merely in field observation and mapping, but in developing a broader comprehension of
earth process evolution on a global level trough time and also in animating and integrating
concepts from different courses. Think of a map with multiple map overlays from geophysics,
geochemistry, archeology, etc. We start this process by introducing stratigraphy in the context of
understanding why the litho sequence exists in the area being mapped. We accomplish this
broader task over a number of classes beginning with the Sophomore level gateway course:
Planet Earth. Besides key curriculum concepts, our program makes use of digital data bases and
digital technology. We deliberately include digital technology both in the classroom and
outdoors to accommodate the interests and computer literacy of today’s students.
Sequence of Field courses involving digital mapping: Our department at UC Berkeley has a
long been engaged in field geology instruction. In 1892 Professor Andrew Lawson taught the
first systematic field geology course in the U.S. Ever since that time mapping on paper
topographic base maps using colored pencils has been the norm. In 1999, George Brimhall
introduced digital mapping into our introductory field course, Earth and Planetary Science (EPS)
101 using pen tablet PC portable computers following a 6-week introduction using traditional
methods. This class was renamed Field Geology and Digital Mapping. Every year, the class still
starts out with paper methods but then shifts into using modern digital instrumentation.
In 1999, digital mapping was introduced into our summer field course (EPS 118
Advanced Field Course) for which EPS 101 is a prerequisite. Pen tablet PC computers supported
by on-line, plug-in card GPS became the norm for all mapping in our summer field course.
Digital Mapping Lab: The Digital Mapping Lab was developed to support software
development and map data base creation. The GeoMapper software package was developed at
UC Berkeley for use in field instruction and research. GeoMapper is copyrighted by the
University of California.
Development of GeoMapper©
The development of mapping software called GeoMapper at UC Berkeley
emerged from the dual needs for fully-functional mapping software and the recognition of the
importance of retaining traditional mapping protocols that together prepare students for present
day careers in earth science. GeoMapper was developed by George Brimhall and Abel Vanegas
of the Department of Earth and Planetary Science, UC Berkeley. GeoMapper consists of two
computer programs. Program PenMap© is a 3-D GIS program of Strata Software providing
technical surveying capabilities, device drivers for GPS and lasers, and raw graphics elements
(points, lines and areas) (Kramer, 2000). GeoMapper© is the front end of the
GeoMapper/PenMap system and provides the visual user-interface that allows a geologisit to
implement the mapping using intuitive, self-explanatory buttons that are touched using a stylus
(Brimhall et al, 2006). A detailed description of the features and use of GeoMapper© is given in
Brimhall and Vanegas (2001) and Brimhall et al. (2002). GeoMapper as a comprehensive but
flexible user-friendly top end or Visual User Interface (VUI) to PenMap to exercise the full
range of mapping capabilities required by modern job markets. Presently geo-science careers
include geo-hazards (earthquakes, volcanoes, landslides, cliff erosion), environmental
(contaminated site remediation, safety evaluation of nuclear power installations), geo-technical,
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and exploration (oil, gas, coal, and metals). Given the diversity of these professional mapping
requirements, we chose the Anaconda Mapping System as the basis for GeoMapper (Brimhall et
al, 2006). Our system is both comprehensive but flexible as it can be customized. GeoMapper
consequently supports mapping of general geology, lithologies, formations, mineralization, and
wall rock alteration. Types of samples include rocks, water, soils, and infrared spectra as well as
digital images that show on the map the direction of the photograph and a link to view it frmm
the map file. Field notes are likewise captured at desired locations and shown on the map.
Another key feature of GeoMapper is the ability to easily develop a mapping legend for each
new project area. For each project area a specific mapping legend can be developed with specific
lithologies and formations appropriate for that area. Files are managed by project area.
GeoMapper, copyrighted by The University of California, supports selection of digital base maps
including topography, ortho-images, geophysics (gravity, magnetics, epicenters, etc.) as well as
supports mapping contacts, structure attitudes (strike and dip, trend and plunge etc.) outcrops,
and color infills.
Publications on GeoMapper
Kramer, John H., 2000, Digital mapping systems for field data collection, in D. R.
Soller, ed. Proceedings of a Workshop on Digital Mapping techniques: U. S.
Geological Survey, Open-file Report 00-325, p. 13-19, in D. R. Soller, ed.
Proceedings of a Workshop on Digital Mapping techniques: U. S. Geological
Survey, Open-file Report 00-325, p. 13-19,
http://pubs.usgs.gov/of/2000/of00-325/kramer.html
Brimhall, G. H and Vanegas, A., 2001, Removing Science Workflow Barriers to Adoption of
Digital Geological Mapping by Using the GeoMapper Universal Program and Visual
User Interface: in D. R. Soller ed., Digital Mapping Technqiues’01- Workshop
proceedings: U. S. Geological Survey Open File Report 01-223, p. 103-114,
http://pubs.usgs.gov/of/2001/of01-223/brimhall.html
Brimhall, G. H, Vanegas and Derek Lerch, A., 2002, GeoMapper Program for paperless field
mapping with seamless map production in ESRI ArcMap and GeoLogger for drill-hole
data capture: Applications in geology, astronomy, environmental remediation and raised
relief models in D. R. Soller ed., Digital Mapping Technqiues’02- Workshop
Proceedings: U. S. Geological Survey Open File Report 02-370, p 141- 151.
http://pubs.usgs.gov/of/2002/of02-370/brimhall.html
Brimhall, G. H, Dilles, John, Proffett, J., 2006, The Role of Geological Mapping in Mineral
In mineral Exploration, in Wealth Creation in the Minerals Industry, Special Publication
12, Anniversary Publications of the Society of Economic Geologists, p. 221-241.
Peterson, E., Heidrick, T., and Frost, E., 2007, Software review of GeoMapper Computer
Program by Brimhall and Vanegas, Computers in Geoscience, v. 33, p. 294-296.
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Abstracts on GeoMapper:
Brimhall, G., Stanton, E., Nunnelley, G., Hillman, B., and Kramer, J., 1998, Direct digital field
mapping using pen-based PC computers supported by differential global positioning
systems and laser range finders, Geol. Soc. Amer. Abstracts with Programs, v. 30, no. 7,
p. A-256.
Montero Sanchez, I. and Brimhall G., 1998, Novel application of digitally integrated mapping
systems for the mineralogical characterization of abandoned mines: , Geol. Soc. Amer.
Abstracts with Programs, v. 30, no. 7, p. A-358.Brimhall, G., 1999, Evaluation of digital
mapping classes in introductory and advanced field classes at UC Berkeley, Geol. Soc.
Amer. Abstracts with Programs, v. 32, no. 7, p. A-191.
Montero Sanchez, I., Brimhall, G., Alpers, C., 1999, Use of UV/VIS/IS spectroscopy to
characterize mine waste dumps in the Penn Mine, Calaveras County, California: Geol.
Soc. Amer. Abstracts with Programs, Cordilleran Section meeting, v. 31, no. 6, p. A91.
Brimhall G. and Vanegas, A., 2000, Digital mapping of geology and ore deposits with
GeoMapper, Geol. Soc. Amer. Abstracts with Programs, v. 32, no. 7, p. A-514.
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