fbpx

Rockin’ Pop-Up: Terrestrial Planets of our Solar System

Join the Geology Gents, Gavin and Graham, for the first installment of a three-part trilogy exploring the planets of our solar system. February will examine the terrestrial planets: Mercury, Venus, Earth, and Mars.

About the Series: Join the Geology Gents, Gavin Piccione and Graham Edwards, for monthly conversations about rocks live on Facebook. Each month we’ll explore a different geologic topic, from Santa Cruz formations to tips for being a more effective rockhound. Submit your questions ahead of time by emailing events@santacruzmuseum.org and feel free to include pictures of rocks you’d like identified! Note: you do not need to have a Facebook account to be able to watch the program live.

Watch Past Pop-Ups
Read our blog Rock Record

Pollinators and Urban Community Gardens with Stacy Philpott

Pollinators are essential to our environment, but habitat loss, pesticide use, and introduced diseases are causing issues for these creatures all over the world. During this talk, Stacy Philpott will share her research from the past decade exploring how urban garden and landscape management influence pollinators. We’ll tour urban gardens near Santa Cruz and learn about some of the factors that lead to successful pollination and pollinator diversity, as well as issues with parasites and pathogens.

About the Speaker

Stacy Philpott is a Professor of Environmental Studies and Director of the Center for Agroecology at UC Santa Cruz. She is an agroecologist interested in community ecology, ecosystem services, urban agroecology, and interactions between agriculture, conservation, and farmer well-being. Stacy has worked for more than 20 years to understand how farm management and the landscapes surrounding farms influence diversity of insects, plants, and birds on farms, and the ecological interactions among species. She has worked in tropical agroforestry systems in Mexico and Indonesia, annual cropping systems in Nicaragua, and in urban agricultural systems in Michigan, Ohio, and California. She has written more than 140 research articles and book chapters. 

This program is in support of our new exhibit, Pollinators: Keeping Company With Flowers, on view January 15-March 6. Sponsored by 90.3 KAZU, Kenneth S. Norris Center for Natural History, and UCSC’s Center for Agroecology.

Climate Stewardship: Taking Collective Action to Protect California with Adina Merenlender

Across California, communities are addressing wildfires, climate justice, urban heat islands, ocean temperature rise, and other climate issues in an effort to make natural, working, and urban landscapes more resilient. During this talk, author Adina Merenlender will share stories from her recently published book, Climate Stewardship: Taking Collective Action to Protect Californiawhich highlights the real work being done by everyday citizens throughout the state to address climate change.

RESOURCES

SANTA CRUZ STEWARDSHIP GROUPS

About the Speaker

Adina Merenlender is a Cooperative Extension Specialist at University of California, Berkeley, and is an internationally recognized conservation biologist known for land-use planning, watershed science, landscape connectivity, and naturalist and stewardship training. She has authored more than 100 published works in the field of conservation science.

Merenlender started the California Naturalist Program and served as its founding director, which to date has graduated over 4,000 certified California Naturalists. Building on the success of this program, Merenlender helped start the first public education and service program on climate stewardship, including writing Climate Stewardship: Taking Collective Action to Protect California with Brendan Buhler. The two programs provide collective impact on ecological health through community and citizen science.

Ancient Scorched Seeds and Indigenous Land Stewardship with Rob Cuthrell

Archaeologists can analyze charred seeds and other plant remains to learn about relationships between people and the natural world deep into the past. This talk will describe how a collaborative research project between Amah Mutsun Tribal Band, State Parks, and academic researchers utilized this type of information to explore how Indigenous peoples on the coast of San Mateo and Santa Cruz Counties used prescribed burning to steward local landscapes. Guided by these findings, Amah Mutsun Land Trust is working to revitalize Indigenous-based stewardship of open spaces today.

Resources

Learn about the Amah Mutsun

Learn about Amah Mutsun relationships with fire

Resources mentioned in the talk

About the Speaker

Rob Cuthrell is a researcher in archaeology and historical ecology who has studied relationships between Indigenous people and landscapes west of the Santa Cruz Mountains for over a decade. Currently, Rob works as a consultant for Amah Mutsun Land Trust managing a native plant propagation and restoration project on Año Nuevo Point.

This program is in support of the exhibit Seeds: Nature’s Artful Engineering, on view at the Santa Cruz Museum of Natural History through November 28.

Fossil Walruses and Other Ancient Life in the Monterey Bay with Dr. Robert Boessenecker

Though our coast today is inhabited by sea lions, harbor seals, and elephant seals, none of these species existed in California 3-5 million years ago. Instead, fossils from the Purisima Formation tell a very different story of strange walruses and early fur seals that inhabited our coast. These include the ancestor of the modern northern fur seal (today a rare visitor to Monterey Bay), the bizarre “double tusked” walrus Gomphotaria, and the toothless walrus Valenictus. Several discoveries made by local collectors and paleontologists represent new species — and you’re going to hear new data and findings never reported before during this presentation.

Join us on National Fossil Day for this member-exclusive presentation with longtime friend of the Museum, Dr. Robert Boessenecker.

Dr. Robert Boessenecker

“I grew up in Foster City on the peninsula, disappointed as a dinosaur nerd kid that there weren’t much in the way of dino fossils from California – which I mistook for “no interesting fossils at all”. Once in high school I visited some shark tooth sites in Scott’s Valley and became obsessed with marine mammal fossils none of the fossil collectors could identify. As an undergraduate student at Montana State University, I started collecting and researching a marine mammal fauna I discovered in Half Moon Bay; I continued with my master’s thesis at MSU on the preservation and stratigraphic context of Purisima Formation fossils, and then went to University of Otago in New Zealand to do my Ph.D. on early baleen whales from much older rocks down under. I have been at the College of Charleston in South Carolina, studying early baleen whales and dolphins, and once again researching Purisima Formation sharks, fish, birds, turtles, and marine mammals.”

-Dr. Robert Boessenecker

About the series

Zoom into the stories, secrets, and science of our collections during monthly webinars with Collections Manager Kathleen Aston. This live event is an extension of our monthly Collections Close-Up blog, with added insights and intrigue. Members are invited to participate in this program before it is made available to the general public as well as ask questions directly of Kathleen.

Not yet a Member? Join today!

Your support helps us steward our collections and offer educational programs that connect people with nature and science. Memberships start at just $15/year.

Rock Record: Panther Beach, an Extraordinary Geologic Feature in Santa Cruz

Written by Gavin Piccione

One of the most exciting perks of having an appreciation for geology is the limitless possibility to find new geologic features, even on the most seemingly mundane trips outside. It may be an interesting pebble that catches your eye or a new outcrop that piques your interest, but one usually does not have to travel far to find thought-provoking rocks. However, within this vast collection of terrestrial curiosities, some features stand out as particularly exceptional or interesting.

On a recent trip to Panther Beach, I experienced the thrill of discovering one of these remarkable geologic marvels hiding just up the coast. In this installation of Rock Record, I cover why the rocks at Panther Beach in Santa Cruz are a world-renowned sedimentary outcrop, and I investigate how this truly unique part of the cliff was deposited here.

The Rocks at Panther Beach

At first glance the rocks at Panther beach may look very familiar to folks who have spent time in Santa Cruz, with cliff walls of the main section of beach made up of the crumbly, beige sedimentary rock called Santa Cruz mudstone. However, if you head to the south-end of the beach, and pass under the archway, the rocks change drastically. Instead of the highly uniform mudstone, the rocks on this side are wavy, laminated sandstones (see image 1). Below these peculiar sandstones there are darker rocks, called dolomite-cemented sands, that have bands that tilt down and towards the southeast. If one breaks or scratches these dolomite-cemented sands, they may smell the faint odor of petroleum. The contact between these two rock types is high irregular, looking almost as if the dolomite-cemented sands were bubbled up into the wavy sandstones like liquid in a lava lamp (see images 2 and 3). Capping these two sandstones is the familiar Santa Cruz mudstone that makes up the rest of the cliff (see full outcrop in image 4).

Image 1: Wavy sandstone at Panther Beach
Image 2: Contact between the wavy sandstone, and the dolomite-cemented sandstone. Image from Sherry, et al. 2012
Image 3: Contact between the wavy sandstone, and the dolomite-cemented sandstone. Image from Sherry, et al. 2012
Image 4: Panther Beach outcrop. Image modified from Sherry et al. 2012

Formation of the Panther Beach Outcrop: The World’s Largest Sedimentary Injection Deposit

When geologists see large sections of rock that are unrelated to the surrounding rock, we often think of some surface process like motion along a fault, that may bring two different rock types in contact. However, at Panther Beach there is no evidence for a fault that could have brought the sandstones to the surface. So how did this ~100m section of sandstone become emplaced in a cliff that is otherwise made of Santa Cruz mudstone?

To understand the formation of the Panther beach outcrop we must start about 1 kilometer below the seafloor. Around 9 million years ago off the coast of ancient Santa Cruz, 1000 meters of mud (the Santa Cruz mudstone) was deposited at the bottom of the ocean above a thick sand deposit (the Santa Margarita sandstone). Later, after heat, and pressure turned most of these sediments into rock, the only sediments left were small pockets of Santa Margarita sands that had not been lithified (i.e., turned to rock). Portions of these sand pockets were rich in oil, which created two distinct reservoirs: oil-rich sands and oil-poor sands. These two sand types were spatially separated because of the density difference between oil and water (see image 5).

Image 5: Sediments prior to injection. Schematic modified from Sherry, et al. 2012.

As more mud was deposited atop the Santa Margarita Sands, the pressure on the sand built. Then finally a geologic event, probably either an earthquake or a landslide, shook the sediments causing the slurry of both oil-rich and oil-poor sands to be injected, at a high velocity, into the overlying rock through fractures in the Santa Cruz mudstone. This type of formation is called a sediment injection deposit, where sediments from below are squeezed up into the overlying strata like a tube of toothpaste (see image 6). While the sands were injected, the oil-rich sand slurry would have traveled slower than the oil-poor sands, leaving the oil rich sands below the oil-poor sands. Injection deposits occur in other places on Earth, but the Panther Beach outcrop is the largest sedimentary injection deposit in the world!

Image 6: Sediments after injection. Schematic modified from Sherry, et al. 2012.

Getting to the Panther Beach Outcrop

Image 7: View looking towards the south through the archway in the cliff

Panther Beach is located off Highway 1 about 5 miles north of Santa Cruz. The parking lot for beach access is unmarked but can be found on google maps. The walk to the beach is about 50 yards down a narrow, steep trail (see the image at the start of this post for the view from the top of the trail). Once on the beach, turn left and walk under the arch in the cliff (see image 7). Be careful, this passageway may not be accessible at high tide, use caution when walking through and do not try to pass when water is high! The sedimentary injection deposit makes up the sea cliff beyond the south side of the arch.

The GPS coordinates for Panther Beach are: 36.994, -122.169


Much of the information for this edition of Rock Record was first published in the journal article: Emplacement and dewatering of the world’s largest exposed sand injectite complex, by Timothy Sherry and others.

Reference cited:

Sherry, T. J., Rowe, C. D., Kirkpatrick, J. D. & Brodsky, E. E. Emplacement and dewatering of the world’s largest exposed sand injectite complex. Geochemistry, Geophys. Geosystems 13, 1–17 (2012).

A Guide to the Rocks of Santa Cruz County

Santa Cruz is an area of geologic interest with a complex history of processes that shaped the coastline, bluffs, terraces, and mountains we see today! Wind, waves, earthquakes, fires, and other natural forces have changed and shaped the landscape for millions of years, though humans have only been able to document those changes in the recent past.

Jump To: Formations | Rock Types | Minerals | Resources


Geologic Formations

The above map shows the distribution of different rocks in Santa Cruz County. Each color represents a different kind of rock and, in turn, a particular age. Many of these rocks represent formations.

A geological formation is a basic rock unit that geologists use to group rock layers. Each formation must be distinct enough for geologists to tell it apart from surrounding layers and identify it on a map. A formation can consist of a variety of related or layered rocks, rather than a single rock type. There are over 14 geologic formations in Santa Cruz County. Most of these formations were created through movement of the crust because of tectonic uplift at the subduction zone off the California coast.

Most of the county is underlain by granitic rock. It formed about 100 million years ago from molten rock which cooled very slowly at a depth several miles below the earth’s surface. Since then, this area has been covered by the sea much of the time. Sand, mud and other sediment was deposited on the seafloor and was eventually compressed and hardened into sedimentary rock which was uplifted to form the Santa Cruz Mountains. Many of the sedimentary beds, which were originally horizontal, have been tilted, folded or partly eroded away. In some areas major faults have offset the rocks.

A large fossil in grey rock on the beach.

3 formations are known for fossils in this region:
Purisima Formation (3-7 Ma)
Santa Cruz Mudstone (7-9 Ma)
Santa Margarita Formation (10-12 Ma)

Learn more in our Fossil Guide.

Rock Types of Santa Cruz County

The three basic types of rocks — igneous, metamorphic and sedimentary — occur in Santa Cruz County. All are composed of minerals. Some consist of primarily one mineral, as in the case of marble, while others are an aggregate of many different minerals, as in the case of granite and conglomerate. 

Each rock type in the Santa Cruz area represents a different chapter in this region’s geologic past, and each has its own unique story to tell. The rocks of this area are mostly covered by soil and vegetation, so geologists must rely on scattered outcrops in creek beds, quarries, road cuts and sea cliffs in order to piece together the geologic history. 

Granite, Empire Grade Road

Igneous rocks formed from molten rock called magma. Plutonic rocks, such as granite, gabbro and alaskite, cooled very slowly, solidifying deep below the earth’s surface. This provided time for larger crystals of quartz, feldspar, mica and other minerals to form, giving the rocks a coarse texture. Volcanic rocks, such as basalt, cooled quickly at the earth’s surface and are very fine grained.

Marble, UCSC Quarry

The metamorphic rocks of this area are a geological enigma. They predate the granite rocks and were originally sedimentary rocks such as limestone, shale and sandstone. These were respectively metamorphosed into marble, schist and quartzite by the intrusion of magma about 100 million years ago. How much earlier these rocks were laid down as sediment, however, remains a mystery.

Mudstone, HWY 1 North of Santa Cruz

Sedimentary rocks in the Santa Cruz area originated for the most part from sediment such as mud, sand and gravel that was deposited on the sea floor. Over millions of years chemical alteration and pressure from burial hardened the sediment into rock. These rocks overlie the igneous and metamorphic rocks of this region and are of a younger age. 

Minerals

Minerals are the naturally occurring crystalline substances that make up the rocks around us. Minerals such as quartz, feldspar, and calcite are the most common constituents of rocks in this area. Dozens of other mineral species occur here, but in small amounts. Large, well-formed crystals- the kind most sought after by collectors- are scarce. 

Several minerals in this region have proven to be of great economic importance. Cinnabar (the chief ore of mercury) has been mined extensively at the New Almaden on the east slope of the Santa Cruz Mountains. Calcite (in the form of marble) has long been quarried near Santa Cruz for the manufacturing of lime and cement. 

Benitoite is the California state mineral. This unusual blue crystal was first discovered in 1907 in San Benito County. While benitoite is found in a few places around the world, San Benito County is the only place in the world where gem quality benitoite crystals are found.

Learn more in our Collections Close-Up.

Resources

Explore other resources for better understanding geology, paleontology, and the landscape of the Santa Cruz region.

Explore Online Rock Resources

Books and Papers

Geology at the Museum

On exhibit at the Museum

  • Specimens of common minerals from the region
  • Specimens of common rocks from the region
  • A detailed topographic geologic map of the county
  • Garden: Take a stroll around the Museum’s Garden Learning Center and see if you can spot fossils and other large rock samples.
  • Activities for kids: Multiple dig boxes features Santa Margarita Formation fossils of sand dollars and casts of a fossil sea cow.

Bring rocks home

Rent a kit to explore local rocks at home. Kit rentals are $10 per week and can be requested here (you do not need to be a teacher to request a rental).

Shop the geology and paleontology section of our online store

Santa Cruz Top 5 Geologic Must-Sees

Santa Cruz is an area of geologic interest with a complex history of processes that shaped the coastline, bluffs, terraces, and mountains we see today! Use this map as you walk, bike or ride your way across the county and explore some of the geologic must-sees our area has to offer. Visit our online Guide to the Rocks of Santa Cruz County to dig even deeper into the geology of the region.

Hiking With A Purpose: Post-fire community science with Josie Lesage

After fire, ecosystems can experience many changes. There can be increased risk of erosion and novel species can invade new areas, but fire can also reveal plants that have been waiting years for this natural disturbance to stimulate their seed banks — and there is still much to learn.

As the Santa Cruz community recovers from the impacts of the CZU Lightning Complex fires, we can look to other communities for guidance on where to go from here and how community scientists can help.

Join us for an online presentation from Josie Lesage of the Santa Barbara Botanic Garden and learn about their response to the Thomas Fire that burned through Santa Barbara and Ventura Counties in 2017-2018.

About the Mapping Recovery Project

The Mapping Recovery project leveraged the enthusiasm of over 100 volunteers who surveyed plants and erosion in the Thomas and Whittier fire scars. The project gathered over 5000 data points on the locations of plants in these fire scars, significantly expanding the known locations of many common invasive species, while also identifying populations of some rare or new invasive species. This data is being used to develop a map of priority intervention areas where restoration of native habitat is most needed and will be most beneficial to the ecosystem in the future.

About the Speaker

Josie Lesage works to understand, protect, and restore California habitats using ecological theory as a guide. She has a Ph.D. in Environmental Studies from the University of California, Santa Cruz, where she studied long-term management and community change in California’s coastal prairies. As the Santa Barbara Botanic Garden’s Applied Ecologist, she is interested in understanding how local ecosystems respond to disturbance and restoration intervention, and in building a community of volunteer scientists to steward our local habitats. She is currently involved in several projects related to invasive plant management and ecosystem recovery following fire. Her favorite plants are in the genus Castilleja


Interested in becoming a community scientist? Join us for an iNaturalist training in the Museum’s Garden Learning Center on September 11.

On the Rocks: The Paleontologist’s Paradise

A layered cocktail in a highball glass

This month join us in raising a glass to the field of paleontology (the study of fossils) as we explore geologic time through a layered drink in one of our favorite glasses.

The history of life on earth is measured in millions of years, and humans are only a tiny blip in that long history. While geologic time can be a hard concept to wrap your mind around, people like Aristotle (384–322 BCE) first noticed the presence of fossil shells on land and concluded that the shape of the earth’s surface must have changed over time. Early scholars from across the world also made observations about the layering of rocks, and in 1669 the Danish scholar Steno proposed the Law of Superposition, a key concept to the earth sciences which generally states that stratigraphic layers on the bottom of a sequence will be older than those layered on top of them.

These concepts were the building blocks for the geologic time scale as we know it today. The geologic time scale is broken down into four large eons and each eon is then further broken down into eras, which are in turn divided into periods, epochs and ages. Today, we are living in the Holocene Epoch, going back 11,700 years ago it generally marks the end of the last ice age. The Holocene is also referred to as the Anthropogene, the “Age of Man” as of all recorded human history falls in this time period and it acknowledges the huge impact we have had on the earth.

Explore more about geologic time with videos from our Geology Gents and peruse our Guide to Local Fossil if you want to dig even deeper.

Layered drinks such as this one are both eye-catching and a fun way to experiment with the density of liquids. The force of buoyancy keeps the various layers from mixing as long as you are using liquids with different densities and build your drink with the heavier liquids at the bottom. Explore this resource for the relative densities of various liqueurs for your future cocktail creations.

Ingredients

0.5 oz. Grenadine or other syrup of your choice
1.5 oz. Coconut rum
1 oz. Dark rum
0.5 c. Juice (pineapple or other tropical flavor)
Ice

Recipe

  1. Pour the grenadine into the bottom of your glass.
  2. Fill the glass to the top with ice, trying not to splash the grenadine.
  3. Mix your juice with the coconut rum. Slowly pour over the ice so that the force doesn’t cause it to mix with the grenadine.
  4. Top with carefully poured dark rum.
  5. Garnish with the citrus of your choice.

Alternatives

  1. Substitute the dark rum for blue curacao for a more eye-catching color combination.
  2. For a non-alcoholic option, leave out the rum and experiment with the density of other additives like soda water or coconut cream.

Post by Liz Broughton