Volume XI — The Deep Time Quarterly

Read the ground downward.

A journal published in beds. Each issue is cut as a vertical section: you begin at the topsoil of the present and descend, layer by layer, into rock that predates opinion.

Begin descent ↓ Read the core log

Section total 412.6 m
Oldest bed 1.41 Ga
Logged by M. Fenwick & the Survey
Locality Cairnhold Quarry, Bed 7
Cairn Loess
Depth
1.1 – 3.5 m
Age
12 ka
Type
Wind silt

Bed 01 · Editorial

The thinnest layers hold the loudest arguments.

Loess is dust that agreed to stay. It arrives in a single windy century, settles pale and structureless, and then spends ten thousand years pretending to be ground. We open every issue here because it is the layer most like the news: fine, recent, easily disturbed by a boot.

Below this line the record thickens and slows. A centimetre of shale is a human lifetime spent underwater. A centimetre of loess is a bad Tuesday in the Pleistocene. The design of this publication is an argument about that ratio — thickness is time, and we refuse to set the two at the same weight.

  • Quaternary
  • Aeolian
  • Field essay
Fenwick Sandstone
Depth
3.5 – 9.7 m
Age
210 Ma
Type
Cross-bedded

Bed 02 · Long read

Six metres of desert, filed under one afternoon.

The Fenwick is the fat bed of the section — six metres of amber grain laid down by dunes that walked north for four million years. Its cross-beds curve like the inside of a shell, each set a single storm, each storm a single afternoon that no one recorded and everyone can now read.

We give it the tallest band in the issue because thickness is the only honest editorial hierarchy available to a rock. A headline cannot be bigger than what it sits on. Here the type has room to breathe, columns split, and the reader's scroll slows involuntarily — which is the point.

Quarrymen at Cairnhold call the unit "the long yellow." They cut it in blocks the size of a piano and float them down the cut to the masons. Half the civic buildings in the county are made of a dune that has been dead since before flowers existed.

Look closely at the grain surface and you will find frosted quartz — each sphere polished by collisions in dry air. It is the texture of wind rendered at one-tenth of a millimetre, and it is the reason this band's hatch is a stipple rather than a line.

Continue the section →

Marl Shale
Depth
9.7 – 11.3 m
Age
246 Ma
Type
Laminated

Bed 03 · Marginalia

A thin bed gets a thin band. Sixteen hundred millimetres of still, anoxic water — and one line of type, because that is all the record can afford.

Ochre Claystone
Depth
11.3 – 15.7 m
Age
301 Ma
Type
Fossiliferous

Bed 04 · Specimen register

Four things we pulled out of the ochre.

  • Productid brachiopod

    Complete pedicle valve, 41 mm. Recovered by hand from the weathered face.
    CH-1104
  • Seed-fern frond

    Carbon film on a parting plane; venation legible under raking light.
    CH-1119
  • Tetrapod trackway, partial

    Three manus impressions across 0.8 m. Cast retained; slab left in situ.
    CH-1131
  • Siderite nodule cluster

    Concretionary, iron-rich. Split cleanly to reveal a shrimp-like arthropod.
    CH-1147
Blackpit Seam
Depth
15.7 – 16.6 m

Nine hundred millimetres of compressed forest. Worked 1841–1907. Read the seam ledger →

Cairnhold Conglomerate
Depth
16.6 – 21.6 m
Age
358 Ma
Type
Clast-supported

Bed 05 · Core log

The section, measured.

Borehole CH-07 · logged 14 March · datum: quarry rim
BedUnitTop (m)Thickness (m)Recovery
01Cairn Loess1.12.488%
02Fenwick Sandstone3.56.297%
03Marl Shale9.71.674%
04Ochre Claystone11.34.491%
05Blackpit Seam15.70.963%
06Cairnhold Conglomerate16.65.099%
07Dolerite Sill21.63.2100%

Recovery below 60% is logged as inferred. The conglomerate marks an unconformity: everything between 358 and 1,410 Ma is simply missing from this locality, removed by an erosion surface you can put your thumb on.

Dolerite Sill
Depth
21.6 – 24.8 m
Age
Intrusive
Type
Columnar

Bed 06 · Intrusion

Magma cut across the whole section. So does the mailing list.

A sill ignores stratigraphy — it slides between beds and bakes both contacts. Our quarterly does the same: one dispatch every thirteen weeks, cutting across whatever you were reading.

No more than four dispatches a year.