<p>Zircons from Australia at 4.4Ga, and perhaps basalts from a Canadian island at 4.5Ga.</p>

<p>It would interest you to know the quest of Boston University geochemist Matthew Jackson, who is searching for the oldest basalt and mantle rock that exists.</p>

<p>His work isn't entirely agreed upon, as they are using all kinds of difficult isotopes which are a subject of controversy. Probably the most current information on early basalts are the claims and counter claims relating to Matthew Jackson in published articles, which have a lot of chemistry in them. </p>

<p><a href="http://news.nationalgeographic.com/news/2010/08/100812-worlds-oldest-rocks-magma-earth-nature-science/" rel="noreferrer">http://news.nationalgeographic.com/news/2010/08/100812-worlds-oldest-rocks-magma-earth-nature-science/</a></p>

<p><a href="https://www.bu.edu/today/2012/little-rock-at-center-of-big-controversy/" rel="noreferrer">https://www.bu.edu/today/2012/little-rock-at-center-of-big-controversy/</a></p>

<p><a href="https://scholar.google.fr/scholar?hl=en&amp;as_sdt=0%2C5&amp;q=tungsten+basalt++oldest&amp;btnG=" rel="noreferrer">https://scholar.google.fr/scholar?hl=en&amp;as_sdt=0%2C5&amp;q=tungsten+basalt++oldest&amp;btnG=</a>  </p>

<p>"We've been looking for pieces of the mantle that might have survived the chaotic mixing and churning within the deep Earth," said Boston University geochemist Matthew Jackson.</p>

<p>"We found rocks that reached the surface some 62 million years ago—suggest a whole reservoir of the primordial rock could still lie somewhere beneath the Arctic"</p>

<p>There are moon basalts from 3.7 Ga years ago, they are a bit mysterious, and lunar plagioclase feldspar at 4.5, appear to have formed when feldspar crystallized and floated to the top of a global magma ocean that surrounded the Moon soon after it formed.</p>

CC BY-SA 4.0
2019-06-29T15:26:03.630Z
Unfortunately, I think the teacher is probably expecting a (possibly outdated) answer found in a textbook.
Spencer
CC BY-SA 4.0
2019-06-30T04:43:59.547Z
The zircon research is a reference to update a teacher with. Teacher's don't mind recent info's.
bandybabboon
CC BY-SA 3.0
2017-10-08T17:39:34.377Z
2017-10-08T17:47:39.823Z
2017-10-08T17:47:39.823Z
bandybabboon
<blockquote>
  <p>The oldest geologic units in the study area are the Precambrian
  crystalline (metamorphic and igneous) rocks, which form a
  basement under the Paleozoic, Mesozoic, and Cenozoic rocks and
  sediments. The Precambrian rocks range in age from 1.7 to about
  2.5 billion years, and were eroded to a gentle undulating plain at the beginning of the Paleozoic era (Gries, 1996). The Precambrian rocks
  are highly variable, but are composed mostly of igneous rocks or
  metasedimentary rocks, such as schists and graywackes. The Paleozoic
  and Mesozoic rocks were deposited as nearly horizontal beds.
  Subsequent uplift during the Laramide orogeny and related erosion
  exposed the Precambrian rocks in the crystalline core of the Black
  Hills, with the Paleozoic and Mesozoic sedimentary rocks exposed in
  roughly concentric rings around the core. Deformation during the
  Laramide orogeny contributed to the numerous fractures, folds, and
  other features present throughout the Black Hills. Tertiary intrusive
  activity also contributed to rock fracturing in the  northern Black
  Hills where numerous intrusions exist.</p>
</blockquote>

<p><a href="https://docsbay.net/geologic-setting" rel="nofollow noreferrer">Geologic Setting</a> by USGS Publications Warehouse</p>

CC BY-SA 4.0
2019-06-26T04:09:14.477Z
cut and paste is not how an answer is made,please answer the question in your own words and post links to suport your answer for the ones that wants more information.
trond hansen
CC BY-SA 4.0
2019-06-26T03:02:05.197Z
2019-06-26T03:02:05.197Z
alanmurrie
<p>Just what @comprehensible said, <strong>zircons</strong> from Jack Hills were the <strong>earliest materials (4.4 Ga)</strong> indicating that continental-type igneous rocks are already present on Earth during this period. Note that these zircons are found within metamorphosed conglomerate beds. </p>

<p>However, if we are talking about rocks (aggregates of material), then the <strong>Nuvvuagittuq greenstone belt (more or less 4.28 Ga)</strong> in Canada represents the oldest known crust, which also gives us the oldest rocks on Earth. </p>

<p>Cheers! </p>

CC BY-SA 3.0
2017-10-13T06:16:06.573Z
The question asks specifically for the oldest **igneous** rocks. As far as I know the oldest igneous rocks in the Nuvvuagittuq Greenstone Belt are significantly younger than the metamorphics (~2.7 Ga) but if you have a reference for older ones please edit it into your answer :).
Pont
CC BY-SA 3.0
2017-10-13T16:06:25.843Z
Basalts such as tholeiite, calc-alkalines and boninites were found in Nuvvuagittuq Greenstone Belt. These igneous rocks are dated to be around this age. So basically they are the oldest known igneous rocks.
HammerKid073
CC BY-SA 3.0
2017-10-13T17:57:58.717Z
It would be great if you could edit your answer to add a reference for that and quote the appropriate passage from the source: O'Neil et al. (2012) [10.1016/j.precamres.2012.07.009] don't seem to think that any of the tholeiites, calc-alkalines and boninites survived the 2.7 Ga event unmetamorphosed :).
Pont
CC BY-SA 3.0
2017-10-13T03:38:12.473Z
2017-10-13T03:38:12.473Z
HammerKid073
<p>I remember watching a documentary years ago about diamonds and the places they are found in southern Africa. Apparently they are inclusions in the oldest rocks in that continent, which you could say fill up some sort of very large chimneys in younger rock, going vertically straight down.</p>

<p>So there you would have at least some of the oldest rocks on the planet.</p>

CC BY-SA 3.0
2017-10-09T20:15:52.300Z
2017-10-09T20:15:52.300Z
Obiwan KeNoobie
<p>The previous answer about the evidence of oldest crust is correct but if you are looking for the oldest igneous rocks that is a metamorphosed granitoid that formed 4.2 billion years ago. According to Wikipedia, the Acasta Gneiss is a tonalite gneiss in the Slave craton in Northwest Territories, Canada. The rock of the outcrop was metamorphosed 3.58 to 4.031 billion years ago and is the oldest known intact crustal fragment on Earth. </p>

CC BY-SA 3.0
2017-10-11T07:03:53.663Z
2017-10-11T07:03:53.663Z
Gabija
<p>I'm trying to catch up on my homework for earth science, but I'm having a difficult time searching for an answer to my question.</p>

CC BY-SA 3.0
2017-10-08T19:09:42.993Z
What have you found?
JeopardyTempest
<rocks><homework><igneous>
Where are the oldest igneous rocks found?
Kitty
# Where are the oldest igneous rocks found?

(Asked by: username_0 on 2017-10-08)

I'm trying to catch up on my homework for earth science, but I'm having a difficult time searching for an answer to my question.

**Tags:** rocks, homework, igneous

> **Comments:**
> **username_1**: What have you found?  

---

## 5 answers

### Answer by username_2 on 2017-10-08. Score: 6

Zircons from Australia at 4.4Ga, and perhaps basalts from a Canadian island at 4.5Ga.

It would interest you to know the quest of Boston University geochemist Matthew Jackson, who is searching for the oldest basalt and mantle rock that exists.

His work isn't entirely agreed upon, as they are using all kinds of difficult isotopes which are a subject of controversy. Probably the most current information on early basalts are the claims and counter claims relating to Matthew Jackson in published articles, which have a lot of chemistry in them.

<http://news.nationalgeographic.com/news/2010/08/100812-worlds-oldest-rocks-magma-earth-nature-science/>

<https://www.bu.edu/today/2012/little-rock-at-center-of-big-controversy/>

<https://scholar.google.fr/scholar?hl=en&as_sdt=0%2C5&q=tungsten+basalt++oldest&btnG=>

"We've been looking for pieces of the mantle that might have survived the chaotic mixing and churning within the deep Earth," said Boston University geochemist Matthew Jackson.

"We found rocks that reached the surface some 62 million years ago—suggest a whole reservoir of the primordial rock could still lie somewhere beneath the Arctic"

There are moon basalts from 3.7 Ga years ago, they are a bit mysterious, and lunar plagioclase feldspar at 4.5, appear to have formed when feldspar crystallized and floated to the top of a global magma ocean that surrounded the Moon soon after it formed.

> **Comments:**
> **username_3**: Unfortunately, I think the teacher is probably expecting a (possibly outdated) answer found in a textbook.  
> **username_2**: The zircon research is a reference to update a teacher with. Teacher's don't mind recent info's.  

---

### Answer by username_4 on 2019-06-26. Score: 0

> The oldest geologic units in the study area are the Precambrian
> crystalline (metamorphic and igneous) rocks, which form a
> basement under the Paleozoic, Mesozoic, and Cenozoic rocks and
> sediments. The Precambrian rocks range in age from 1.7 to about
> 2.5 billion years, and were eroded to a gentle undulating plain at the beginning of the Paleozoic era (Gries, 1996). The Precambrian rocks
> are highly variable, but are composed mostly of igneous rocks or
> metasedimentary rocks, such as schists and graywackes. The Paleozoic
> and Mesozoic rocks were deposited as nearly horizontal beds.
> Subsequent uplift during the Laramide orogeny and related erosion
> exposed the Precambrian rocks in the crystalline core of the Black
> Hills, with the Paleozoic and Mesozoic sedimentary rocks exposed in
> roughly concentric rings around the core. Deformation during the
> Laramide orogeny contributed to the numerous fractures, folds, and
> other features present throughout the Black Hills. Tertiary intrusive
> activity also contributed to rock fracturing in the northern Black
> Hills where numerous intrusions exist.

[Geologic Setting](https://docsbay.net/geologic-setting) by USGS Publications Warehouse

> **Comments:**
> **username_5**: cut and paste is not how an answer is made,please answer the question in your own words and post links to suport your answer for the ones that wants more information.  

---

### Answer by username_6 on 2017-10-13. Score: 0

Just what @comprehensible said, **zircons** from Jack Hills were the **earliest materials (4.4 Ga)** indicating that continental-type igneous rocks are already present on Earth during this period. Note that these zircons are found within metamorphosed conglomerate beds.

However, if we are talking about rocks (aggregates of material), then the **Nuvvuagittuq greenstone belt (more or less 4.28 Ga)** in Canada represents the oldest known crust, which also gives us the oldest rocks on Earth.

Cheers!

> **Comments:**
> **username_7**: The question asks specifically for the oldest **igneous** rocks. As far as I know the oldest igneous rocks in the Nuvvuagittuq Greenstone Belt are significantly younger than the metamorphics (~2.7 Ga) but if you have a reference for older ones please edit it into your answer :).  
> **username_6**: Basalts such as tholeiite, calc-alkalines and boninites were found in Nuvvuagittuq Greenstone Belt. These igneous rocks are dated to be around this age. So basically they are the oldest known igneous rocks.  
> **username_7**: It would be great if you could edit your answer to add a reference for that and quote the appropriate passage from the source: O'Neil et al. (2012) [10.1016/j.precamres.2012.07.009] don't seem to think that any of the tholeiites, calc-alkalines and boninites survived the 2.7 Ga event unmetamorphosed :).  

---

### Answer by username_8 on 2017-10-09. Score: -1

I remember watching a documentary years ago about diamonds and the places they are found in southern Africa. Apparently they are inclusions in the oldest rocks in that continent, which you could say fill up some sort of very large chimneys in younger rock, going vertically straight down.

So there you would have at least some of the oldest rocks on the planet.


---

### Answer by username_9 on 2017-10-11. Score: -1

The previous answer about the evidence of oldest crust is correct but if you are looking for the oldest igneous rocks that is a metamorphosed granitoid that formed 4.2 billion years ago. According to Wikipedia, the Acasta Gneiss is a tonalite gneiss in the Slave craton in Northwest Territories, Canada. The rock of the outcrop was metamorphosed 3.58 to 4.031 billion years ago and is the oldest known intact crustal fragment on Earth.


---

