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Department of Earth Sciences


Smartphone & Tablet Compass/Clinometer Apps

Warning from Nigel Woodcock

I keep being told that the complete answer to collecting field orientation data is a smartphone app such as FieldMove Clino. This does a lot of good things, BUT you should be aware of possible errors. This is a regular topic of discussion on the Geotectonics discussion  group at You can sign up there to see the FieldMove Clino thread beginning on 27/8/14, but the gist of the widely held concerns is in the post below from Richard Jones at Geospatial research at Durham. I'm sure that we will get reliable app/smartphone combination within a few years, but be careful in the meantime. 

"We have carried out quite a lot of systematic testing of the suitability of iPhones as compass-clinos for measuring geological planes - and we have experienced very mixed results. 

The good news is that...

  1. We have managed to get good, repeatable results that are approximately as precise as a set of analogue compass-clinos (Silva liquid filled housings, double spirit-level, no electronics). 
  2. Once we're up and running, using an iPhone is much quicker than any analogue compass-clino we've used; so ideal for taking large numbers of measurements from a single sampling site (e.g. fracture transects).
  3. We've now taken many, many thousand measurements with iPhones that we believe are within acceptable precision.

The bad news is that...

  1. if we're not very rigorous in setting-up and calibrating the devices, we usually get randomly bad results.
  2. even if we are very careful, the iPhones sometimes don't self-calibrate properly - so we always cross-check the iPhone against an analogue compass-clino before and after a measurement session.
  3. there's no obvious way of examining the device itself to see whether it's likely to be functioning correctly - you must have another device with which to compare it.

So personally, I'm extremely sceptical of the general validity of any orientation data that have been collected with smartphones - unless the user has documented their calibration procedure carefully, and that the calibration has not relied wholly of the device's own calibration [... or until someone has documented why this isn't necessary]. 
Based on this, I'd also recommend that any orientation data that are published (or form the basis for interpretations that are published) include a statement on the equipment and method used."

Smart phone & tablet apps

  • iGeology gives you an interactive geological map of the UK for use on phones and tablets. Download iGeology from Google Play
  • Rocklogger Android app for measuring rock orientation, strike & dip, and magnetic field - free. Also available is paid version with stereonet plotter
  • eGeo Compass 'The ultimate Android geology compass for geologists' says the web site
  • Google Earth for Mobile—free of charge for Android tablets or phones, also available for iPhones
  • Google translate—available both for Android and iPhone

Images—anywhere around the world

General online resources

These are a series of old Soviet Topographic maps of various places around the world (a longing and the patience to transliterate Cyrillic and/or translate Russian may be an advantage). They are available at the following scales

This site may help with transliteration

These are links from where you can select specific country information. These resources will often just give you an overview of the country with some topographic, and sometimes geological information but in a general way.

Contours to import 

A good resource for worldwide contours is the Global Digital Elevation Map (GDEM) made available by NASA from here: There a number of choices you can make but in all honesty I've only ever tried one and it works fine. You'll need to create an account to be able to download the material you want but it is a simple process and the account is activated immediately. Remember to be as precise as you can with you areas, as the larger the area you request the larger the files you'll have to manipulate. 

General Geological Resources online

  • OneGeology OneGeology is an international initiative of the geological surveys of the world access the viewing portal from here—Remember to click on the View Layers option to add and remove your chosen layers.
  • OpenGeoScience from the BGS. There are 6 sections to explore: Data, Education, Maps, Pictures, Reports, and Software.

Region-specific information


  • Microsoft® Research Maps (formerly TerraServer) is the world's largest searchable image database with zoomable 1-meter resolution USGS digital orthophotos of the U.S.
  • Topozone – Claims to have every USGS topographic map, orthophotomap, and aerial photograph in the entire United States. Fun to play with – and some very good deals on Map Packs (maps, aerial photos etc)
  • National Geological Map database – USGS resource for geological maps and related data
  • National Cooperative Geologic Mapping Program – some potentially useful information about geological mapping projects in general and the ‘how tos’ of mapping. Some useful links on this page
  • Earth Resources Observation and Science (EROS) - Data Center for United States Geological Survey (USGS)
  • U.S. Geological Survey Aerial Photography
  • Electronic Map Library contains a series of maps created by Dr William Bowen, of the Department of Geography at California State University, Northridge. The online collection contains maps which are stored in GIF and JPEG formats and also in PDF, EPS, and TIFF formats. The online maps focus mainly on areas of the United States and include the Digital Atlas of the United States
  • United States Geological Survey publications in the Library. Many of these will have relevant maps for your chosen mapping area. A large amount of USGS material is available on-line at the USGS Publication Warehouse. Search the online catalogue iDiscover for the Geological Survey

Canada/North America


  • Africa: general resources available
  • Madmappers - "GIS data accessible to all" - a bit of a hunt but you will find material there
  • A good resource for 1:50K maps of South Africa is Spatial Reference you'll need to register and log in to downlaod the maps but it is free
  • Digital map of Africa This website (Open File Report 97-470A, version 2.0, 2002) was compiled by the United States Geological Survey (USGS). It is a digital map including geology, oil and gas field locations, and geologic provinces of Africa, as part of a worldwide series of maps in CD-ROM. Maps are in PDF format and can be downloaded with Acrobat Reader. The site contains also links to references and contact information
  • Many African countries have Geological Survey publications, some bulletins, reports or memoirs. We have a lot of these publications, especially the older ones in the Library. Search the online catalogue iDiscover for the Geological Survey for a specific country

Europe—a selection

The Geological Survey of Denmark & Greenland 



  • National Land Survey of Iceland main site full of topographic mappy goodness
  • Here to download 1:50,000 maps
  • Here for a general atlas
  • Here for the general map viewer - you can add and remove/adjust layers


  • ISPRA (Istituto superiore per la protezione e la ricerca ambientale): 1:50 000 Geological maps. Problem 1) Site doesn't (currently) work in English so you have to use the Italian version. Problem 2) The maps are available for viewing ONLY via a Flash viewer. Please let us know if the link doesn't work.
  • This is the Italian Military Geography site map viewer:



  • Some map guidance can be had from the LNEG site - there is some English language translations of the site but not all the pages are
  • And a full Geoportal is available from here, including a map viewer [requires Adobe Flash Player]




    • the geoportal of the Swiss Confederation - for geological maps look under Nature & Environment section
    • Swisstopo Federal Office of Topography


    • The OS
    • Landmap: provides spatial data and learning resources for the UK - Provides orthorectified satellite image mosaics of Landsat, SPOT and ERS radar data and a high resolution Digital Elevation Model for the British Isles. This data is available in formats that are readily accessible to users of Geographic Information Systems, Image Processing and Desktop publishing software
    • Digimap: Cambridge University Library subscribes to this service which delivers Ordnance Survey Map Data to users within UK Tertiary Education via the Internet. You need to have a Raven authentication account to register free of charge for access to Digimap. For more information about Digimap see the University Library Map Room web pages. Please follow this link for information on Raven. Important: Registration takes at least 3 days so plan in advance
    • Geology of Britain (British Geological Survey)
    • GeoIndex: This site provides a map-based index to datasets that have been collected or have obtained from other sources. The Britain Beneath our Feet website provides more generalised maps based on data collected.
    • British Geological Survey publications in the Library. Many of these will have relevant maps for your chosen mapping area. Search the online catalogue iDiscover for the Geological Survey
    • You can find the Ordnance Survey of Ireland (OSI) here and the OSI map viewer. Their GeoPortal is here and here is the map viewer
    • The Geological Survey of Ireland can be found here and their on-line mapping tools are here
    • Ireland – the Library has a number of geological maps. For topographic maps you will need to go to the University Library Map Room
    • For Europe your best bet is to use the Earth Sciences Map Library to check for maps although we do not have everything and may need to order maps in. Also try the general online resources section
    • Many European countries have Geological Survey publications, some bulletins, reports or memoirs. We have a lot of these publications, especially the older ones in the Library. Search the online catalogue iDiscover for the Geological Survey for a specific country

    Australia/New Zealand

    South America

    • Try the general online resources links for South American information, also the USGS often has publications relating to this area
    • Many South American countries have Geological Survey publications, some as bulletins, or reports or memoirs. We have a lot of these publications, especially the older ones in the Library. Search the online catalogue iDiscover for the Geological Survey for a specific country


    • Geological Survey of Brazil in English or CRPM (Companhia de Pesquisa de Recursos Minerais) in Portugese
    • For topographical maps look in IBGE Instituto Brasiliero Geografia e Estatística


    • India Geological Survey
    • Geological Survey publications for many Asian countries are available in the Library in print form as journals, bulletins or reports. Search the online catalogue iDiscover for the Geological Survey for a specific country
    • CHINA  - China Geological Survey data services China GeoData Service. This looks like a really good resource, but so far I have only been able to make it work in the Google Browser - but that's quite handy because you can get it to translate for you should you need it.

    Institutions/Geological Surveys

    • A useful page from Berkeley for Geological surveys and institutions of the relevant country. A strong US focus but a good starting point
    • BGS geoportal - Good way to find out all the details of academic and commercial organizations for you to get in touch with in the country of your mapping project – try and do a text search on the country/region you’re interested in

    Buying maps

    Part II Mapping Projects: The Librarian will purchase topographic maps that you need but in some instances (especially if mapping abroad) it will be cheaper for you to buy the maps whilst there. Always make sure that you will be able to do this before deciding on this course of action. The Librarian needs plenty of advance notice for ordering foreign maps via the normal agents. The Library will buy these maps back from you providing that you have pre-arranged this with the Library staff AND the maps are in good condition.