Introduction

Ancient slopes occur along extinct passive margins and classically represented by their geometries and sedimentary sequences preserved in the rock record. These deepwater slope deposits have developed in conjunction with rimmed carbonate shelves these sequences have been preserved along off-shore margins of intercontinental seaways (Stoudt, 2000). Subsequent uplift has exposed many ancient slope sequences that have been used for modern analogues. Ancient carbonate slopes have been preserved throughout geologic history and are easily observed in outcrops on all of the continents. Please refer to the Comparison table for additional information.

A few examples of preserved ancient slope sequences throughout time

Canning Basin, Australia-Devonian

Guadalupian in the Gudalupe Mountains of West Texas and New Mexico-Permian

McKittrick Canyon- West Texas

Northern Italy-Triassic

Eastern Italy-Jurassic

Vercors, France-Cretaceous

Lake Valley Formation, San Andreas Mountains-California-Cretaceous

Eastern Venezula basin-South America-Cretaceous

    (Stoudt, 2000) & (Rienstoffer and Kendall, 2000)

Sedimentary rock types of ancient carbonate slopes

    1. Carbonates

    2. Micritic mudstones

    3. Packstones

    4. Wackstones

    5.Turbitdite sequences associated with gravity flows

    6.Debris flows

    7.Grain flows

Click here to view comparison chart

Click here to view modern slopes
 

Source:

Tucker, M.E., and P.V. Wright, 1990, Carbonate Sedimentology, Blackwell Scientific Publications: Cambridge, Massachusetts.