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% Packages
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%\usepackage{opensans}          % Can't make this work so far. Shame. Would be lovely.
\usepackage[normalem]{ulem}     % For underlining links
% Most of the following are not required for the majority
% of cheat sheets but are needed for some symbol support.
\usepackage{amsmath}            % Symbols
\usepackage{MnSymbol}           % Symbols
\usepackage{wasysym}            % Symbols
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% Document Info
\author{roobear}
\pdfinfo{
  /Title (geology-of-oceans.pdf)
  /Creator (Cheatography)
  /Author (roobear)
  /Subject (Geology of Oceans Cheat Sheet)
}

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% Commands
\newcommand{\SetRowColor}[1]{\noalign{\gdef\RowColorName{#1}}\rowcolor{\RowColorName}} % Shortcut for row colour
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% Header and Footer
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\fancyhead{} % Set header to blank
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\fancyhead[L]{
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{C}
    \SetRowColor{DarkBackground}
    \vspace{-7pt}
    {\parbox{\dimexpr\textwidth-2\fboxsep\relax}{\noindent
        \hspace*{-6pt}\includegraphics[width=5.8cm]{/web/www.cheatography.com/public/images/cheatography_logo.pdf}}
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\columnbreak
\begin{tabulary}{11cm}{L}
    \vspace{-2pt}\large{\bf{\textcolor{DarkBackground}{\textrm{Geology of Oceans Cheat Sheet}}}} \\
    \normalsize{by \textcolor{DarkBackground}{roobear} via \textcolor{DarkBackground}{\uline{cheatography.com/171741/cs/36096/}}}
\end{tabulary}
\end{multicols}}

\fancyfoot[L]{ \footnotesize
\noindent
\begin{multicols}{3}
\begin{tabulary}{5.8cm}{LL}
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  \mymulticolumn{2}{p{5.377cm}}{\bf\textcolor{white}{Cheatographer}}  \\
  \vspace{-2pt}roobear \\
  \uline{cheatography.com/roobear} \\
  \end{tabulary}
\vfill
\columnbreak
\begin{tabulary}{5.8cm}{L}
  \SetRowColor{FootBackground}
  \mymulticolumn{1}{p{5.377cm}}{\bf\textcolor{white}{Cheat Sheet}}  \\
   \vspace{-2pt}Not Yet Published.\\
   Updated 14th December, 2022.\\
   Page {\thepage} of \pageref{LastPage}.
\end{tabulary}
\vfill
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\begin{tabulary}{5.8cm}{L}
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  \vspace{-5pt}
  %\includegraphics[width=48px,height=48px]{dave.jpeg}
  Measure your website readability!\\
  www.readability-score.com
\end{tabulary}
\end{multicols}}




\begin{document}
\raggedright
\raggedcolumns

% Set font size to small. Switch to any value
% from this page to resize cheat sheet text:
% www.emerson.emory.edu/services/latex/latex_169.html
\footnotesize % Small font.

\begin{multicols*}{3}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Studying the Ocean Floor}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{{\bf{Geophysical Methods}} \newline % Row Count 1 (+ 1)
~ {\bf{Sonar}}: depth is established through reflecting soundwaves from the ocean floor by measuring the velocity of sound waves in water and the time required for the wave to hit the floor. \newline % Row Count 5 (+ 4)
~ {\bf{Multi-beam sonar}}: employs multiple signals to map a stretch of the seafloor \newline % Row Count 7 (+ 2)
{\bf{Satellites}} \newline % Row Count 8 (+ 1)
{\bf{Submarines}} \newline % Row Count 9 (+ 1)
{\bf{Oceans Network Canada}} - Generate sonar data into images \newline % Row Count 11 (+ 2)
{\bf{Field study through direct observations on land}}% Row Count 13 (+ 2)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Active Continental Margins}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{Continental slope descends abruptly into a deep-ocean trench; Accumulation of sediments form an accretionary wedge onto the non-subducting tectonic plate at a convergent plate boundary.% Row Count 4 (+ 4)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Mid-Oceanic Ridges (MOR)}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{A continuous range of underwater volcanoes that make up 20\% of earth's surface; down faulted structures called rift valleys; sea floor spreading at crest of ridges; consists of many layers of basaltic rock. \newline % Row Count 5 (+ 5)
{\bf{Structure:}} \newline % Row Count 6 (+ 1)
{\bf{Upper layer}} - Consisting of pillow lava \newline % Row Count 7 (+ 1)
{\bf{Middle layer}} - Numerous interconnected sheeted dikes  \newline % Row Count 9 (+ 2)
{\bf{Lower layer}} - {\bf{{\emph{Gabbro}}}}% Row Count 10 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{{\bf{Gabbro}} - intrusive equivalent of basalt}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Topographic Units}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{{\bf{Continental margins}}  \newline % Row Count 1 (+ 1)
{\bf{Deep ocean margins}} \newline % Row Count 2 (+ 1)
{\bf{Mid ocean ridges}}% Row Count 3 (+ 1)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
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\par\addvspace{1.3em}

\begin{tabularx}{5.377cm}{X}
\SetRowColor{DarkBackground}
\mymulticolumn{1}{x{5.377cm}}{\bf\textcolor{white}{Passive Continental Margins}}  \tn
\SetRowColor{white}
\mymulticolumn{1}{x{5.377cm}}{{\bf{Continental slope}} - marks the seaward edge of the continental shelf; boundary between continental crust and oceanic crust; represents true edge of continent; represents original rift (Pangea splitting); cut by {\bf{{\emph{submarine canyons}}}} \newline % Row Count 5 (+ 5)
{\bf{Continental Rise}} - at the base of the slope; thick accumulation of sediment in {\bf{{\emph{deep sea fans}}}}, containing {\bf{{\emph{turbidites}}}}% Row Count 8 (+ 3)
} \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\SetRowColor{LightBackground}
\mymulticolumn{1}{x{5.377cm}}{{\bf{Submarine canyons}} - steep sided valley with nearly vertical walls \newline {\bf{Deep sea fans}} - the layer of sediment below the submarine fan \newline {\bf{{\emph{Turbidites}}}} - fine grained sediment that was deposited by strong downward flow of water containing high amounts of sediment, called turbidity current}  \tn 
\hhline{>{\arrayrulecolor{DarkBackground}}-}
\end{tabularx}
\par\addvspace{1.3em}


% That's all folks
\end{multicols*}

\end{document}