Sedimentology of Kingston Peak Formation KP1 Beds in Beck Canyon Region, Kingston Range, California

<p>The Neoproterozoic Kingston Peak Formation (KPF) is known for its diamictites interpreted as of glacial origin. The KPF overlies the Beck Spring Dolomite (BSD) that contains microfossils and microbialites. This study aims to test correlation between outcrops and understand the abrupt change from BSD to KPF. It focuses on the basal 4 meters of the KP1 subunit of the KPF as it appears in the Beck Canyon region, Kingston Range, California. We describe and correlate sedimentary rocks at and immediately overlying the contact and analyze the sedimentary structures, textures and sequences. We have found only three sites in the northern Kingston Peak Range where the contact can be observed. At each site we measured sections about 4 meters long across the contact. The top of the BSD in all locations contains microbial laminations, oncoids, pisoids, sheets of chert and peloids. Thin sections from about 15 cm below the contact to about 50 cm above the contact show microbial laminations with some peloids or ghosts of peloids and abundant chert. The base of the KPF is composed of millimeter to centimeter-scale alternating two bed types named A-bed and B-bed. A-beds are clastic-rich and B-beds are dolomite-rich. A-beds are dolomitic silty mudstones with abundant muscovite. B-beds are recrystallized silty dolostones with peloid ghosts. A few of the </p> <p>beds show faint current ripple cross bedding, cross bedding and lenticular structures. A to B bed contacts are sharp. At all stratigraphic levels, clastics have immature textures and compositions. XRD and thin section analysis show a trend of decreasing dolomite up-section. Measurement and analysis of individual alternating bed thickness show cyclical patterns and a gradational increase in bed thickness to massive sandstones. Mineralogical patterns, pisoid-rich layers, and bed thickness patterns can all be correlated among the three sections. The pattern of increasing clastic content and bed thickness upsection suggests clastic influx during progradation that progressively overwhelmed carbonate production. This progradational setting could have occurred on a tide dominated delta or on a prograding tidal flat. The BSD-KPF contact at Kingston Range most likely represent a sequence boundary as evidenced by a change in lithology from dolostones to clastics.</p>

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Basic Sciences

Year

2016

Author dc:creator

• Ombati, Dominic Joel

Contributors dc:contributor

• Nick, Kevin E.
• Awramik, Stanley
• Buchheim, H. Paul

• Earth Sciences
• Geology
• Sedimentology
• Sedimentology; Geology - Stratigraphic-- Neoproterozoic;
• Neoproterozoic formations; Kingston Peak Formation; Beck Spring Dolomite; Sedimentary Structures

Statement dc:rights

• This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Language dc:language

English

Repository record dc:identifier

https://scholarsrepository.llu.edu/etd/399

OAI identifier oai:identifier

oai:scholarsrepository.llu.edu:etd-1397