GEOCLASTICA Ltd

Dr ROGER HIGGS
rogerhiggs@geoclastica.com
cc to rogerhiggs@hotmail.com

Consulting in:
Sedimentology, Sequence Stratigraphy &
Climate- & Sea-Level Change

 

BLOCKLEY COTSWOLD GEOLOGICAL WALKS

PHOTO of Blockley village and some of the locals. Spring-fed Blockley Brook runs along the valley floor, behind the trees. Forming the high ground of the valley sides is Middle Jurassic 'Cotswold limestone', deposited in a warm shallow sea about 170 million years ago. The valley floor is on Lower Jurassic 'Lias' shale, which has yielded fossil plesiosaur (marine reptile) skeletons at Blockley brickworks. Springs emerge at many places along the junction between limestone (highly permeable) and shale (impermeable).


INTRODUCTION ...

Beginning in April 2024, 2.5-hour walks (public and private; see below) explaining Blockley's fascinating Jurassic geology and valuable geological resources, chiefly: (1) brick-clay (Blockley brickworks active since 1925; supplied Battersea Power Station bricks); (2) building-stone, namely the famous 'Cotswold limestone'; (3) world-class fossils including plesiosaurs; and (4) groundwater-springs. Blockley grew wealthy in the 18th and 19th centuries, thanks to mills powered by the spring-fed Blockley Brook.

Blockley village, jewel of the Cotswolds and located in an 'Area of Outstanding Natural Beauty' (AONB), is a magnet for walkers (intersection of the 'Monarch's Way', 'Heart of England Way' and 'Diamond Way') and also for fans of the 'Father Brown' TV series, filmed here. Blockley has many holiday cottages and a popular cafe/restaurant (Blockley Cafe, see below), next-door to a well-stocked shop. There are also two pubs. Blockley is a 4-mile, 13-minute bus ride from Moreton-in-Marsh railway station, which is just 90 minutes by direct hourly train from London Paddington, stopping in glorious Oxford. Or you can catch the very frequent 'Airline' coach from Heathrow to Oxford's Gloucester Green bus terminus (90-100 minutes), then stroll to the rail station (10 minutes) and catch the same train there (30 minutes to Moreton).


LEARN ABOUT ...

'Cotswold stone', vital historic building material

Cotswold fossils

Groundwater-springs


LOCAL GEOLOGY ...

Here's my 2023 invited slideshow (downloadable pdf) presented to Blockley Discussion Group, entitled "Blockley's bountiful Jurassic geology: brick clay, building stone, groundwater springs, and world-class fossils" ... Weblink

Two main rock types:

1. Lower Jurassic shales (Lias Group), including Charmouth Mudstone Formation (same as at Lyme Regis), used for making bricks at Blockley brickworks, which has yielded spectacular fossil plesiosaurs (marine reptiles) ... Weblink

... overlain by ...

2. Middle Jurassic 'Cotswold limestone' (Birdlip Limestone Formation, lowest unit of Inferior Oolite Group). Source of building-stone, groundwater and fossils.

Springs emerge at the contact between the limestone (highly permeable) and the underlying shale (impermeable).


WHAT YOU'LL SEE ...

Local 'Cotswold limestone' fossils from my own collection: 'shellfish' (bivalves and brachiopods) and 'sea urchins' (echinoids).

Local 'Cotswold limestone' building-blocks in the walls of Blockley Church. Using my hand-lenses, we'll examine both main types: 'broken-shell limestone' and 'oolitic limestone'.

Two 'Cotswold limestone' exposures (small road-cuts).

'Russell Spring' ... Weblink

Spring-fed Blockley Brook, which powered about a dozen historical mills.

Spring-fed 'Bishops Fish Pond'.

'Park Farm Spring' near top of Blockley Downs.

Distant view of Blockley brickworks.

PLEASE NOTE: you are unlikely to find any whole fossils (to take home), unless we happen upon a freshly ploughed field.


PUBLIC WALKS ...

2.5 hours, in and around Blockley, about 3 miles.

Most Saturdays, 10am-12.30pm, starting April 2024.

Departs from front of Blockley Cafe (coffee, WCs) ... Weblink

Free roadside parking throughout Blockley village.

£20 cash per person (pay at end). Sorry, no children under 11 and no dogs, except on private walks (see below).

Maximum 20 participants.

Email rogerhiggs@hotmail.com to check that the walk is 'on' and to secure a place. Alternatively, message me on WhatsApp +44 7879 907950 (no voice calls please).


PRIVATE WALKS for schools, clubs, families ...

Any day (except Saturday), at any time you choose.

Same 2.5-hour itinerary as public walks (above).

£100 cash per group of up to 5 persons (any age; babies free). Sixth and each additional person £20. Pay at end.

... or ...

... alternative 4-hour, 5-mile circular route, adding (1) world-renowned Batsford Arboretum (cafe, WCs, picnic benches) via Heart of England Way across Blockley Downs, (2) Bourton-on-the-Hill village (groundwater-spring; abandoned 'Cotswold limestone' quarry; pub), and (3) 'Hailstones Spring' (main source of Blockley Brook).

£160 cash per group of up to 5 persons (any age; babies free). Sixth and each additional person £30. Pay at end.

... or ...

... propose a different route!

Email rogerhiggs@hotmail.com to discuss/arrange.


DISCLAIMER to be signed by all adult participants ...
"I understand that my participating in this Blockley Cotswold Geological Walk, led by Dr Roger Higgs, involves climbing over a stile and walking on many types of surface (e.g. paved roads and footpaths, gravel roads, cobbled road, stairs, grass, mud), some of which are uneven and may be slippery. In two places, our route crosses a public road used by vehicles. The walking-trail (Heart of England Way) up Blockley Down crosses a field in which sheep and/or cattle are often present. I/we acknowledge that adequate clothing and footwear with good grip are essential. Neither I, nor anyone in my party, nor any family member, nor any company or institution to which I am attached, will hold Dr Roger Higgs, or his one-man geological-consulting company Geoclastica Ltd, responsible for any loss or harm (injury or death) to myself or to anyone in my party, howsoever caused."


Tripadvisor 5-star reviews of my Cornish 'Bude Geo-Walks' ... Weblink


My contributions (published, unpublished; literature and lectures) on geology, climate and sea-level ... Weblink


For photos of me(!) 'in action' with a well-known celebrity, click on 'Bude Cornwall Geological Walks' in the menu below.

GEOCLASTICA LTD
 
Homepage CV & Publications
Climate & Sea Level Advice Petroleum Sedimentology Course
Turbidite Reservoir Analogs Lecture Outcrop Analog Field Trips
Core & Outcrop Facies Logging Sandstone Porosity Prediction
Blockley Cotswold Geological Walks Bude Cornwall Geological Walks
Non-Exclusive Exploration Reports for Sale:
Trinidad Venezuela