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Virtual Rocks
GSA TODAY | AUGUST 2016 Declan G. De Paor, Department of Physics and Department of courses, and social media pages. Reynolds et al. (2002) and
Ocean, Earth, and Atmospheric Sciences, Old Dominion Bennington and Merguerian (2003) used QuickTime Virtual
University, Norfolk, Virginia 23529, USA, ddepaor@odu.edu Reality (QTVR) to display interactive digital specimens. The
Smithsonian Museum has a large collection of scanned 3D
ABSTRACT objects (Smithsonian, 2016), and the British Geological Survey
(2016) has assembled more than 1,800 virtual fossils. Numerous
Three-dimensional digital models of geological objects are rela- LiDAR models of outcrops have been made (Clegg et al., 2005;
tively easy to create and geolocate on virtual globes such as Google McCaffrey et al., 2008; Buckley et al., 2010; see also Passchier,
Earth and Cesium. Emerging technologies allow the design of 2011, and VOG, 2016).
realistic virtual rocks with free or inexpensive software, relatively
inexpensive 3D scanners and printers, and smartphone cameras More recently, geoscientists have created many virtual speci-
linked to point-cloud computing services. There are opportunities mens for paleontological functional analysis, digital exchange of
for enhanced online courses, remote supervision of fieldwork, research data, and teaching in a range of geoscience subdisci-
remote research collaboration, and citizen-science projects, and plines. For example, Pugliese and Petford (2001) revealed 3D melt
there are implications for archiving, peer-review, and inclusive topology of veined micro-diorite, and Bates et al. (2009) estimated
access to specimens from inaccessible sites. Virtual rocks can be dinosaur bone mass from models.
gradually altered to illustrate geological processes such as weath-
ering, deformation, and metamorphic mineral growth. This paper Modelers have long used 3D scanners, and, more recently, 3D
surveys applications in a wide range of geoscience subdisciplines printers (Hasiuk, 2014) to create ever-more sophisticated virtual
and includes downloadable examples. Detailed instructions are objects. Cohen et al. (2010) reconstructed archaeological vessels
provided in the GSA Supplemental Data Repository1. from virtual ceramic shards, harnessing the computer’s power to
solve 3D jigsaw puzzles. Engineering geologists Dentale et al.
INTRODUCTION (2012) used FLOW-3D® software to test a virtual breakwater built
out of individual virtual stones and accropodesTM. Medical
In recent decades, numerous virtual field trips have been CT-scanning methodologies were used by Hoffmann et al. (2014)
created to simulate in-person field excursions; however, one to study buoyancy in virtual cephalopods, by Carlson et al. (2000)
aspect of physical fieldwork is not commonly replicated: virtual for igneous texture studies, and by Pamukcu et al. (2013) to
explorers do not often return to their computer desktops with examine glass inclusions in quartz crystals. Rohrback-Schiavone
collections of virtual rocks! There are multiple justifications for and Bentley (2015) employed GIGAmacroTM hardware to create
creating interactive 3D digital models of rocks, minerals, fossils, grain-scale sedimentological models. Root et al. (2015) compared
drill core, geo-archaeological objects, and outcrops. For example, models of Neolithic monuments in Ireland and the Middle East,
one can (i) reveal 3D features hidden inside solid specimens; (ii) while Mounier and Lahr (2016) created a 3D model of the skull of
archive samples destined for destructive testing; (iii) prepare for the common ancestor of humans and Neanderthals. Structural
field trips and reinforce learning and retention after the fact; (iv) geologists Thiele et al. (2015) gained new insights into en échelon
aid peer-review and supplement electronic publications; (v) give vein formation, and Favalli et al. (2012) modeled outcrops, a
access to geological materials for disabled and other non-tradi- volcanic bomb, and a stalagmite. They concluded that the quality
tional students; and (vi) provide access to collections locked away of virtual outcrops or specimens is comparable to LiDAR outcrops
in storage drawers, given that museums and other repositories or laser-scanned specimens, respectively.
display only a small fraction of their holdings.
In recent years, the most exciting developments in 3D modeling
The concept of a virtual specimen is not new. Following the include the availability of smartphone apps and associated point-
mechanical tomography of Sollas (1904), Tipper (1976) used a cloud computing services that non-specialists can quickly master.
grinding wheel to serial-section fossils. He traced outlines with a The purpose of this paper is to highlight the recent, current, and
digitizing tablet, created 3D models with a mainframe computer, potential future role of virtual specimens in diverse aspects of
and interacted with them using a graphics storage tube (relatively geoscience education and research.
youthful readers can image-google “graphics storage tube”),
exploring previously hidden inner surfaces. CREATING VIRTUAL SPECIMENS WITH SKETCHUP
Virtual geological collections already exist online, and readers Virtual specimens can be created with a digital camera and
may simply link content to their own virtual field trips, online SketchUp (2016). SketchUp exports a model as a COLLADA file
optionally zipped with a KML document and one or more texture
GSA Today, v. 26, no. 8, doi: 10.1130/GSATG257A.1.
1 GSA Supplemental Data Repository Item 2016173, detailing techniques for creating virtual specimens along with figure animations, is online at www.geosociety.org/
pubs/ft2016.htm. If you have questions, please contact GSA Today, P.O. Box 9140, Boulder, CO 80301-9140, USA; gsatoday@geosociety.org.
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