Rock Units. A lithostratigraphic unit is defined as a body of sedimentary, extrusive igneous, metasedimentary, or metavolcanic strata which is distinguished on the basis of lithologic characteristics and stratigraphic position (position in the rock sequence).The smallest lithostratigraphic rock unit is the bed.edimentary environments that started out side-by-side will end up overlapping one another over time due to sea level change (transgressions and regressions). The result is a vertical sequence of beds. The vertical sequence of facies mirrors the original lateral distribution of sedimentary environments.
The US Supreme Court, as an institution, is head of the Judicial Branch. The Chief Justice of the United States presides over the Court and is the head of the judiciary during his (or her) tenure, but the Associate Justices don't really play a leadership role.
Party leaders of the United States Senate. The Senate Majority and Minority Leaders are two United States Senators who are elected by the party caucuses that hold the majority and the minority. These leaders have the most time serving in the senate from both major parties. The current leaders are Republican Majority Leader Mitch McConnell of Kentucky and Democratic Minority Leader Chuck Schumer of New York. The current Assistant Majority Leader is Republican John Cornyn of Texas.