What Effect Has Granite Had Upon The Sedimentary Strata

This was not freshly made rock either but oceanic crustal basalt that was 34 to 85 million years old.

What effect has granite had upon the sedimentary strata.

Sedimentary structures are the larger generally three dimensional physical features of sedimentary rocks. Sedimentary rocks are formed from pre existing rocks or pieces of once living organisms. While it is possible for layering to form in other rocks it is the singular. Both these observations indicate the granite had the constituency of a hot magma that flowed as it forced its way up and into the host sedimentary strata rather than being a cold solid body that was tectonically emplaced.

It had none of the mud clay ooze or manganese nodules that cover the rest of the deepest sea. Assume that you have just examined several flat lying sedimentary layers. Sedimentary rock sedimentary rock sedimentary structures. At the contact with the granite the host fossiliferous sedimentary strata have been metamorphosed and in this instance have wkxv ehhq pruh uhvlvwdqw wr zhdwkhulqj rsolq 6qhoolqj vallance 1969.

Then between 70 and 30 million years ago through the action of plate tectonics the whole region was uplifted resulting in the high and relatively flat colorado plateau. The layers range from several millimetres to many metres in thickness and vary greatly in shape. Also notice that the bedding of the sedimentary layers has been disturbed near the contact. Many of the picturesque views of the desert southwest show mesas and arches made of layered sedimentary rock common sedimentary rocks.

In other words the researchers discovered a strange 85 million year gap in the geological record. Stratification the layering that occurs in most sedimentary rocks and in those igneous rocks formed at the earth s surface as from lava flows and volcanic fragmental deposits. Sedimentary structures include features like bedding ripple marks fossil tracks and trails and mud cracks. After much study you determine that there is a considerable span of time for which no sedimentary rock layer exists at this site.

Strata may range from. They form from deposits that accumulate on the earth s surface. Tilted strata lie below the unconformity and bedding in younger strata above is parallel to the unconformity. Sedimentary strata can even be found atop mountain ranges where rock layers have been lifted thousands of feet.

Weathered the granite is well exposed in road and railroad cuts and in the hills around its margins which have been mapped in detail. Above these old rocks lie layer upon layer of sedimentary rock each telling a unique part of the environmental history of the grand canyon region. They are best seen in outcrop or in large hand specimens rather than through a microscope.